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+-----------------+------+----------+-----+----+-----+---------------+
| **REPORT        |      |          |     |    | *F  |               |
| DOCUMENTATION   |      |          |     |    | orm |               |
| PAGE**          |      |          |     |    | App |               |
|                 |      |          |     |    | rov |               |
|                 |      |          |     |    | ed* |               |
|                 |      |          |     |    |     |               |
|                 |      |          |     |    | *   |               |
|                 |      |          |     |    | OMB |               |
|                 |      |          |     |    | No. |               |
|                 |      |          |     |    | 0   |               |
|                 |      |          |     |    | 704 |               |
|                 |      |          |     |    | -01 |               |
|                 |      |          |     |    | 88* |               |
+-----------------+------+----------+-----+----+-----+---------------+
| Public          |      |          |     |    |     |               |
| reporting       |      |          |     |    |     |               |
| burden for this |      |          |     |    |     |               |
| collection of   |      |          |     |    |     |               |
| information is  |      |          |     |    |     |               |
| estimated to    |      |          |     |    |     |               |
| average 1 hour  |      |          |     |    |     |               |
| per response,   |      |          |     |    |     |               |
| including the   |      |          |     |    |     |               |
| time for        |      |          |     |    |     |               |
| reviewing       |      |          |     |    |     |               |
| instructions,   |      |          |     |    |     |               |
| searching       |      |          |     |    |     |               |
| existing data   |      |          |     |    |     |               |
| sources,        |      |          |     |    |     |               |
| gathering and   |      |          |     |    |     |               |
| maintaining the |      |          |     |    |     |               |
| data needed,    |      |          |     |    |     |               |
| and completing  |      |          |     |    |     |               |
| and reviewing   |      |          |     |    |     |               |
| the collection  |      |          |     |    |     |               |
| of information. |      |          |     |    |     |               |
| Send comments   |      |          |     |    |     |               |
| regarding this  |      |          |     |    |     |               |
| burden estimate |      |          |     |    |     |               |
| or any other    |      |          |     |    |     |               |
| aspect of this  |      |          |     |    |     |               |
| collection of   |      |          |     |    |     |               |
| information,    |      |          |     |    |     |               |
| including       |      |          |     |    |     |               |
| suggestions for |      |          |     |    |     |               |
| reducing this   |      |          |     |    |     |               |
| burden, to      |      |          |     |    |     |               |
| Washington      |      |          |     |    |     |               |
| Headquarters    |      |          |     |    |     |               |
| Services,       |      |          |     |    |     |               |
| Directorate for |      |          |     |    |     |               |
| Information     |      |          |     |    |     |               |
| Operations and  |      |          |     |    |     |               |
| Reports, 1215   |      |          |     |    |     |               |
| Jefferson Davis |      |          |     |    |     |               |
| Highway, Suite  |      |          |     |    |     |               |
| 1204,           |      |          |     |    |     |               |
| Arlington, VA   |      |          |     |    |     |               |
| 22202-4302, and |      |          |     |    |     |               |
| to the Office   |      |          |     |    |     |               |
| of Management   |      |          |     |    |     |               |
| and Budget,     |      |          |     |    |     |               |
| Paperwork       |      |          |     |    |     |               |
| Reduction       |      |          |     |    |     |               |
| Project         |      |          |     |    |     |               |
| (0704-0188),    |      |          |     |    |     |               |
| Washington, DC  |      |          |     |    |     |               |
| 20503.          |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 1\. AGENCY USE  |      | 2\.      |     | 3  |     |               |
| ONLY *(Leave    |      | REPORT   |     | \. |     |               |
| blank)*         |      | DATE     |     | RE |     |               |
|                 |      |          |     | PO |     |               |
|                 |      | November |     | RT |     |               |
|                 |      | 2004     |     | TY |     |               |
|                 |      |          |     | PE |     |               |
|                 |      |          |     | A  |     |               |
|                 |      |          |     | ND |     |               |
|                 |      |          |     | D  |     |               |
|                 |      |          |     | AT |     |               |
|                 |      |          |     | ES |     |               |
|                 |      |          |     | C  |     |               |
|                 |      |          |     | OV |     |               |
|                 |      |          |     | ER |     |               |
|                 |      |          |     | ED |     |               |
|                 |      |          |     |    |     |               |
|                 |      |          |     | F  |     |               |
|                 |      |          |     | in |     |               |
|                 |      |          |     | al |     |               |
|                 |      |          |     | Re |     |               |
|                 |      |          |     | po |     |               |
|                 |      |          |     | rt |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 4\. TITLE AND   |      |          |     |    | 5\. |               |
| SUBTITLE        |      |          |     |    | F   |               |
|                 |      |          |     |    | UND |               |
| M3 Urban Maglev |      |          |     |    | ING |               |
| -- FTA Final    |      |          |     |    | N   |               |
| Report          |      |          |     |    | UMB |               |
|                 |      |          |     |    | ERS |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 6\. AUTHOR(S)   |      |          |     |    |     |               |
|                 |      |          |     |    |     |               |
| R. Thornton, T  |      |          |     |    |     |               |
| Clark, J        |      |          |     |    |     |               |
| Wieler, B.      |      |          |     |    |     |               |
| Perreault,      |      |          |     |    |     |               |
| Walter Eggers   |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 7\. PERFORMING  |      |          |     |    | 8\. |               |
| ORGANIZATION    |      |          |     |    | P   |               |
| NAME(S) AND     |      |          |     |    | ERF |               |
| ADDRESS(ES)     |      |          |     |    | ORM |               |
|                 |      |          |     |    | ING |               |
| MagneMotion     |      |          |     |    | ORG |               |
|                 |      |          |     |    | ANI |               |
| 20 Sudbury      |      |          |     |    | ZAT |               |
| Road, Acton, MA |      |          |     |    | ION |               |
| 01720           |      |          |     |    | REP |               |
|                 |      |          |     |    | ORT |               |
|                 |      |          |     |    |     |               |
|                 |      |          |     |    | NUM |               |
|                 |      |          |     |    | BER |               |
|                 |      |          |     |    |     |               |
|                 |      |          |     |    | TBP |               |
|                 |      |          |     |    | -10 |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 9\.             |      |          |     |    | 1   |               |
| SPONSO          |      |          |     |    | 0\. |               |
| RING/MONITORING |      |          |     |    | SPO |               |
| AGENCY NAME(S)  |      |          |     |    | NSO |               |
| AND ADDRESS(ES) |      |          |     |    | RIN |               |
|                 |      |          |     |    | G/M |               |
| U.S. Department |      |          |     |    | ONI |               |
| of              |      |          |     |    | TOR |               |
| Transportation  |      |          |     |    | ING |               |
| , Federal       |      |          |     |    | AGE |               |
| Transit         |      |          |     |    | NCY |               |
| Administration, |      |          |     |    |     |               |
|                 |      |          |     |    | REP |               |
| Office of       |      |          |     |    | ORT |               |
| Technology, 400 |      |          |     |    | NUM |               |
| Seventh Street, |      |          |     |    | BER |               |
| SW, Washington, |      |          |     |    |     |               |
| DC 20590        |      |          |     |    | MA- |               |
|                 |      |          |     |    | 26- |               |
|                 |      |          |     |    | 707 |               |
|                 |      |          |     |    | 7-0 |               |
|                 |      |          |     |    | 2.0 |               |
|                 |      |          |     |    | 4.2 |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 11\.            |      |          |     |    |     |               |
| SUPPLEMENtary   |      |          |     |    |     |               |
| NOTES           |      |          |     |    |     |               |
|                 |      |          |     |    |     |               |
| COTR: Mary      |      |          |     |    |     |               |
| Anderson, FTA   |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 12a.            |      |          |     |    | 1   |               |
| DISTRIBUTI      |      |          |     |    | 2b. |               |
| ON/AVAILABILITY |      |          |     |    | DIS |               |
| STATEMENT       |      |          |     |    | TRI |               |
|                 |      |          |     |    | BUT |               |
| Limited         |      |          |     |    | ION |               |
| Distribution    |      |          |     |    | C   |               |
| Available From: |      |          |     |    | ODE |               |
| National        |      |          |     |    |     |               |
| Technical       |      |          |     |    | N/A |               |
| Information     |      |          |     |    |     |               |
| Service, 5285   |      |          |     |    |     |               |
| Port Royal      |      |          |     |    |     |               |
| Road,           |      |          |     |    |     |               |
| Springfield, VA |      |          |     |    |     |               |
| 22161. Phone:   |      |          |     |    |     |               |
| 703-605-6000;   |      |          |     |    |     |               |
| Fax:            |      |          |     |    |     |               |
| 703-605-6900    |      |          |     |    |     |               |
|                 |      |          |     |    |     |               |
| Email:          |      |          |     |    |     |               |
| orders@ntis.gov |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 13\. ABSTRACT   |      |          |     |    |     |               |
| *(Maximum 200   |      |          |     |    |     |               |
| words)*         |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| The MagneMotion |      |          |     |    |     |               |
| Urban Maglev    |      |          |     |    |     |               |
| System, called  |      |          |     |    |     |               |
| *M3*, is        |      |          |     |    |     |               |
| designed as an  |      |          |     |    |     |               |
| alternative to  |      |          |     |    |     |               |
| all             |      |          |     |    |     |               |
| conventional    |      |          |     |    |     |               |
| guided          |      |          |     |    |     |               |
| transportation  |      |          |     |    |     |               |
| systems.        |      |          |     |    |     |               |
| Advantages      |      |          |     |    |     |               |
| include major   |      |          |     |    |     |               |
| reductions in   |      |          |     |    |     |               |
| travel time,    |      |          |     |    |     |               |
| operating cost, |      |          |     |    |     |               |
| capital cost,   |      |          |     |    |     |               |
| noise, and      |      |          |     |    |     |               |
| energy          |      |          |     |    |     |               |
| consumption.    |      |          |     |    |     |               |
| Small vehicles  |      |          |     |    |     |               |
| operating       |      |          |     |    |     |               |
| automatically   |      |          |     |    |     |               |
| with headways   |      |          |     |    |     |               |
| of only a few   |      |          |     |    |     |               |
| seconds can be  |      |          |     |    |     |               |
| safely operated |      |          |     |    |     |               |
| in clusters to  |      |          |     |    |     |               |
| achieve         |      |          |     |    |     |               |
| capacities of   |      |          |     |    |     |               |
| more than       |      |          |     |    |     |               |
| 12,000          |      |          |     |    |     |               |
| passengers per  |      |          |     |    |     |               |
| hour per        |      |          |     |    |     |               |
| direction.      |      |          |     |    |     |               |
| Small vehicles  |      |          |     |    |     |               |
| lead to lighter |      |          |     |    |     |               |
| guideways,      |      |          |     |    |     |               |
| shorter wait    |      |          |     |    |     |               |
| time for        |      |          |     |    |     |               |
| passengers,     |      |          |     |    |     |               |
| lower power     |      |          |     |    |     |               |
| requirements    |      |          |     |    |     |               |
| for wayside     |      |          |     |    |     |               |
| inverters, more |      |          |     |    |     |               |
| effective       |      |          |     |    |     |               |
| regenerative    |      |          |     |    |     |               |
| braking and     |      |          |     |    |     |               |
| reduced station |      |          |     |    |     |               |
| size. The       |      |          |     |    |     |               |
| result of the   |      |          |     |    |     |               |
| design is a     |      |          |     |    |     |               |
| system that can |      |          |     |    |     |               |
| be built for    |      |          |     |    |     |               |
| about \$25M per |      |          |     |    |     |               |
| mile, excluding |      |          |     |    |     |               |
| vehicles,       |      |          |     |    |     |               |
| stations and    |      |          |     |    |     |               |
| land            |      |          |     |    |     |               |
| acquisition.    |      |          |     |    |     |               |
|                 |      |          |     |    |     |               |
| The vehicles    |      |          |     |    |     |               |
| have arrays of  |      |          |     |    |     |               |
| permanent       |      |          |     |    |     |               |
| magnets to      |      |          |     |    |     |               |
| provide         |      |          |     |    |     |               |
| suspension and  |      |          |     |    |     |               |
| guidance forces |      |          |     |    |     |               |
| and also        |      |          |     |    |     |               |
| provide the     |      |          |     |    |     |               |
| field for the   |      |          |     |    |     |               |
| Linear          |      |          |     |    |     |               |
| Synchronous     |      |          |     |    |     |               |
| Motor (LSM)     |      |          |     |    |     |               |
| propulsion      |      |          |     |    |     |               |
| system.         |      |          |     |    |     |               |
| Feed            |      |          |     |    |     |               |
| back-controlled |      |          |     |    |     |               |
| currents in     |      |          |     |    |     |               |
| control coils   |      |          |     |    |     |               |
| wound around    |      |          |     |    |     |               |
| the magnets     |      |          |     |    |     |               |
| stabilize the   |      |          |     |    |     |               |
| suspension and  |      |          |     |    |     |               |
| provide active  |      |          |     |    |     |               |
| lateral         |      |          |     |    |     |               |
| damping. The    |      |          |     |    |     |               |
| LSM windings    |      |          |     |    |     |               |
| are integrated  |      |          |     |    |     |               |
| with the        |      |          |     |    |     |               |
| suspension      |      |          |     |    |     |               |
| rails and       |      |          |     |    |     |               |
| excited by      |      |          |     |    |     |               |
| inverters       |      |          |     |    |     |               |
| located along   |      |          |     |    |     |               |
| the guideway.   |      |          |     |    |     |               |
| The vehicle     |      |          |     |    |     |               |
| size and        |      |          |     |    |     |               |
| maximum speed   |      |          |     |    |     |               |
| can be varied   |      |          |     |    |     |               |
| over a wide     |      |          |     |    |     |               |
| range to        |      |          |     |    |     |               |
| accommodate     |      |          |     |    |     |               |
| virtually all   |      |          |     |    |     |               |
| applications    |      |          |     |    |     |               |
| served today by |      |          |     |    |     |               |
| other guided    |      |          |     |    |     |               |
| transportation  |      |          |     |    |     |               |
| systems.        |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 14\. SUBJECT    |      |          |     |    | 1   |               |
| TERMS           |      |          |     |    | 5\. |               |
|                 |      |          |     |    | NUM |               |
| Maglev,         |      |          |     |    | BER |               |
| Magnetic        |      |          |     |    | OF  |               |
| Levitation,     |      |          |     |    | PA  |               |
| Propulsion,     |      |          |     |    | GES |               |
| Urban,          |      |          |     |    |     |               |
| Requirements,   |      |          |     |    | 83  |               |
| Performance,    |      |          |     |    |     |               |
| Safety, Design, |      |          |     |    |     |               |
| Analysis, Cost  |      |          |     |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+
|                 |      |          |     |    | 1   |               |
|                 |      |          |     |    | 6\. |               |
|                 |      |          |     |    | PR  |               |
|                 |      |          |     |    | ICE |               |
|                 |      |          |     |    | C   |               |
|                 |      |          |     |    | ODE |               |
|                 |      |          |     |    |     |               |
|                 |      |          |     |    | N/A |               |
+-----------------+------+----------+-----+----+-----+---------------+
| 17\. SECURITY   | 18\. |          | 1   |    |     | 20\.          |
| CLASSIFICATION  | SECU |          | 9\. |    |     | LIMITATION OF |
| OF              | RITY |          | SE  |    |     | ABSTRACT      |
|                 | CL   |          | CUR |    |     |               |
| REPORT          | ASSI |          | ITY |    |     |               |
|                 | FICA |          | CL  |    |     |               |
| Unclassified    | TION |          | ASS |    |     |               |
|                 |      |          | IFI |    |     |               |
|                 | OF   |          | CAT |    |     |               |
|                 | THIS |          | ION |    |     |               |
|                 | PAGE |          |     |    |     |               |
|                 |      |          | OF  |    |     |               |
|                 | Uncl |          | AB  |    |     |               |
|                 | assi |          | STR |    |     |               |
|                 | fied |          | ACT |    |     |               |
|                 |      |          |     |    |     |               |
|                 |      |          | Unc |    |     |               |
|                 |      |          | las |    |     |               |
|                 |      |          | sif |    |     |               |
|                 |      |          | ied |    |     |               |
+-----------------+------+----------+-----+----+-----+---------------+

NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89)

Prescribed by ANSI Std. 239-18

298-102

**NOTICE**

This document is disseminated under the sponsorship of the U.S.
Department of Transportation in the interest of information exchange.
The United States Government assumes no liability for its contents or
use thereof.

The United States Government does not endorse products of manufacturers.
Trade or manufacturer's names appear herein solely because they are
considered essential to the objective of this report.

Foreword

This Final Report is written in fulfillment of FTA Project
MA-26-7077-02. As part of this project we have completed investigations
on critical aspects of the Urban Maglev system called *M3*, MagneMotion
Maglev. This report documents the maglev system architecture, provides a
high level description of all components and their performance
characteristics, presents the findings of our initial cost analysis, and
outlines our development plan.

Our intended audience is managers and engineers with working knowledge
of transportation systems and technology. The report supersedes the
final report generated as part of FTA Project MA-26-7077-01.

**Abbreviations and Acronyms**

AASHTO American Association of State Highway and Transportation
Officials

APM Automated People Mover

DSP Digital Signal Processor

EDS ElectroDynamic Suspension

EMS ElecctroMagnetic Suspension

FTA Federal Transit Administration

HSST High Speed Surface Transportation

IGBT Insulated Gate Bipolar Transistor

IPT Inductive Power Transfer

ISO International Standards Organization

LRFD Load and Resistance Factor Design

LIM Linear Induction Motor

LSM Linear Synchronous Motor

NCHRP National Cooperative Highway Research Program

NdFeB Neodymium-Iron-Boron magnet material

pphpd passengers per hour per direction

**Metric Conversion Factors**

The following Table gives factors for converting units used in this
report. To convert from English to Metric multiply by the E→M factor, to
convert from Metric to English multiply by the M→E factor.

+----------------+-----------+------------+-------------+-------------+
|                | *E unit*  | *M unit*   | *E→M*       | *M→E*       |
+----------------+-----------+------------+-------------+-------------+
| Distance       | inch      | mm         | 25.4        | 0.0394      |
|                |           |            |             |             |
|                | foot      | m          | 3.2808      | 0.3048      |
|                |           |            |             |             |
|                | mile      | km         | 1.6093      | 0.6214      |
+----------------+-----------+------------+-------------+-------------+
| Mass           | lb        | kg         | 0.4536      | 2.2046      |
|                |           |            |             |             |
|                | ton       | Mg         | 0.9072      | 1.1023      |
+----------------+-----------+------------+-------------+-------------+
| Speed          | mph       | m/s        | 0.4470      | 2.2369      |
|                |           |            |             |             |
|                | mph       | km/h       | 1.6093      | 0.6214      |
+----------------+-----------+------------+-------------+-------------+
| Energy         | BTU       | kJ         | 1.0544      | 0.9484      |
|                |           |            |             |             |
|                | BTU       | Wh         | 0.2929      | 3.4149      |
+----------------+-----------+------------+-------------+-------------+

**MagneMotion Urban Maglev - FTA Final Report**

**Project MA-26-7077-02.04.2**

**MagneMotion**

**20 Sudbury Road**

**Acton, MA 01720**

**November, 2004**

Table of Contents

Foreword...........................................................................\...iii

[Abstract 1](#abstract)

[Executive Summary 1](#executive-summary)

[1 Introduction 4](#introduction)

[2 Overview 6](#overview)

[3 Electromagnetic suspension and guidance
9](#electromagnetic-suspension-and-guidance)

[3.1 Permanent magnet EMS 9](#permanent-magnet-ems)

[3.2 Lateral guidance and damping 10](#lateral-guidance-and-damping)

[3.3 Horizontal and vertical turns 11](#horizontal-and-vertical-turns)

[4 Linear Motor Propulsion 13](#linear-motor-propulsion)

[4.1 Comparison of synchronous and asynchronous linear motors
13](#comparison-of-synchronous-and-asynchronous-linear-motors)

[4.2 The tradeoff between cost and performance
14](#the-tradeoff-between-cost-and-performance)

[4.3 Block length optimization 14](#block-length-optimization)

[4.4 Propulsion power system and inverter design
15](#propulsion-power-system-and-inverter-design)

[4.5 Power distribution and control 17](#power-distribution-and-control)

[4.6 Performance simulation 18](#performance-simulation)

[4.7 Efficiency and energy consumption
20](#efficiency-and-energy-consumption)

[4.8 LSM manufacturing 21](#lsm-manufacturing)

[5 Guideway 22](#guideway)

[5.1 Beam design 22](#beam-design)

[5.2 Beam statics and dynamics 24](#beam-statics-and-dynamics)

[5.3 Comparison of steel and concrete beams
24](#comparison-of-steel-and-concrete-beams)

[5.4 Ride quality analysis of baseline design
34](#ride-quality-analysis-of-baseline-design)

[5.5 Concrete beam creep considerations
39](#concrete-beam-creep-considerations)

[6 Vehicle 41](#vehicle)

[6.1 Size 41](#size)

[6.2 Headway and capacity considerations
42](#headway-and-capacity-considerations)

[6.3 Weight 42](#weight)

[6.4 Secondary suspension 42](#secondary-suspension)

[6.5 Onboard power system 43](#onboard-power-system)

[6.6 Use of larger vehicles or trains
43](#use-of-larger-vehicles-or-trains)

[7 Control System 44](#control-system)

[7.1 Introduction 44](#introduction-1)

[7.2 Objectives 44](#objectives)

[7.3 Architecture 44](#architecture)

[7.4 Proposed control scheme 46](#proposed-control-scheme)

[7.5 Simulation 48](#simulation)

[8 Demonstration prototype 51](#demonstration-prototype)

[8.1 Static load test results 52](#static-load-test-results)

[8.2 Lateral stiffness test results 53](#lateral-stiffness-test-results)

[8.3 Lateral damping test results 54](#lateral-damping-test-results)

[8.4 Magnet optimization 59](#magnet-optimization)

[8.5 Conclusions 59](#conclusions-1)

[9 Application examples 60](#application-examples)

[9.1 Shuttle 60](#shuttle)

[9.2 One-way loop 62](#one-way-loop)

[9.3 Airport connector 63](#airport-connector)

[9.4 Intercity 64](#intercity)

[9.5 Summary 65](#summary)

[10 Cost estimates 67](#cost-estimates)

[10.1 Guideway 67](#guideway-1)

[10.2 LSM stator 68](#lsm-stator)

[10.3 Power system 68](#power-system)

[10.4 Vehicle 69](#vehicle-1)

[10.5 Control electronics and software
69](#control-electronics-and-software)

[10.6 Cost summary 70](#cost-summary)

[11 Continuing development 71](#continuing-development)

[11.1 Expanded indoor test facility 71](#expanded-indoor-test-facility)

[11.2 Site development 71](#site-development)

[11.3 Converging interests for East Providence Development Project
72](#converging-interests-for-east-providence-development-project)

[11.4 Action plan for East Providence
73](#action-plan-for-east-providence)

[12 Conclusion 74](#conclusion)

**Table of Figures**

[Fig. 2.1. Preliminary vehicle and guideway design.
7](#__RefHeading___Toc89856168)

[Fig. 2.2. Cross-section of guideway beam and preliminary vehicle
suspension. 8](#__RefHeading___Toc89856169)

[Fig. 3.1. A vehicle's magnet pod attracted upwards to a suspension
rail. 10](#__RefHeading___Toc89856170)

[Fig. 3.2. Vertical gap and lateral force vs. lateral displacement.
11](#__RefHeading___Toc89856171)

[Fig. 3.3. Suspension mechanism showing pod pivoting for turns.
12](#__RefHeading___Toc89856172)

[Fig. 3.4. Top view of suspension system.
12](#__RefHeading___Toc89856173)

[Fig. 4.1. Contours of constant inefficiency in the force vs. speed
domain. 17](#__RefHeading___Toc89856174)

[Fig. 4.2. Power distribution system. 18](#__RefHeading___Toc89856175)

[Fig. 4.3. Distance, speed and power profiles for a 3.2 km (2 mi) trip.
19](#__RefHeading___Toc89856176)

[Fig. 5.1. Alternate beam section with dimensions in meters.
23](#__RefHeading___Toc89856177)

[Fig. 5.2. ISO Standard for acceptable vertical acceleration for good
ride quality. 30](#__RefHeading___Toc89856178)

[Fig. 5.3. Vertical acceleration spectrum at 45 m/s on concrete
guideway. 31](#__RefHeading___Toc89856179)

[Fig. 5.4. New guideway beam for increased gauge.
34](#__RefHeading___Toc89856180)

[Fig. 5.5. Vertical acceleration of a rigid vehicle at 45 m/s.
35](#__RefHeading___Toc89856181)

[Fig. 5.6. Vertical acceleration spectrum for rigid vehicle at 45 m/s.
36](#__RefHeading___Toc89856182)

[Fig. 5.7. Vehicle front-end-bounce mode -- f = 1.41 Hz.
37](#__RefHeading___Toc89856183)

[Fig. 5.8. Vehicle rear-end-bounce mode -- f = 1.87 Hz.
37](#__RefHeading___Toc89856184)

[Fig. 5.9. Acceleration history for sprung vehicle at 60 m/s (134 mph).
38](#__RefHeading___Toc89856185)

[Fig. 5.10. Acceleration spectrum for sprung vehicle at 60 m/s (134
mph). 39](#__RefHeading___Toc89856186)

[Fig. 7.1. Hierarchical control system. 45](#__RefHeading___Toc89856187)

[Fig. 7.2. Two clusters of vehicles. 47](#__RefHeading___Toc89856188)

[Fig. 7.3. Typical Simulation of a 4 bay station with 6 vehicles.
49](#__RefHeading___Toc89856189)

[Fig. 7.4. Station throughput as a function of the number of bays.
49](#__RefHeading___Toc89856190)

[Fig. 8.1. Photograph of prototype vehicle and guideway.
51](#__RefHeading___Toc89856191)

[Fig. 8.2. Maglev test vehicle. 53](#__RefHeading___Toc89856192)

[Fig. 8.3. Lateral displacement test setup.
53](#__RefHeading___Toc89856193)

[Fig. 8.4. Lateral stiffness measurement results.
54](#__RefHeading___Toc89856194)

[Fig. 8.5. Lateral dynamics with K~v~ = -9.1 N/(mm/sec) × dz/dt
55](#__RefHeading___Toc89856195)

[Fig. 8.6. Lateral dynamics with K~v~ = -13 N/(mm/sec) × dz/dt.
56](#__RefHeading___Toc89856196)

[Fig. 8.7. Lateral dynamics with K~v~ = -9.1 N/(mm/sec) × dz/dt, force
limit of 910 N. 56](#__RefHeading___Toc89856197)

[Fig. 8.8. Lateral dynamics with K~v~ = -13 N/(mm/sec) × dz/dt, force
limit of 910 N. 56](#__RefHeading___Toc89856198)

[Fig. 8.9. Lateral step response with no damping.
58](#__RefHeading___Toc89856199)

[Fig. 8.10. Lateral step response with lateral damping.
58](#__RefHeading___Toc89856200)

[Fig. 8.11. Lateral step response with lateral damping and roll torque
compensation. 59](#__RefHeading___Toc89856201)

## Abstract {#abstract .unnumbered}

The MagneMotion Urban Maglev System, called *M3*, is designed as an
alternative to all conventional guided transportation systems.
Advantages include major reductions in travel time, operating cost,
capital cost, noise, and energy consumption. Bus size vehicles operating
automatically with headways of only a few seconds can be safely operated
in clusters to achieve capacities of more than 12,000 passengers per
hour per direction. Small vehicles lead to lighter guideways, shorter
wait time for passengers, lower power requirements for wayside
inverters, more effective regenerative braking and reduced station size.
The result of the design is a system that can be built for about \$25M
per mile, excluding vehicles, stations and land acquisition.

The vehicles have arrays of permanent magnets to provide suspension and
guidance forces and also provide the field for the Linear Synchronous
Motor (LSM) propulsion system. Feedback-controlled currents in control
coils wound around the magnets stabilize the suspension and provide
active lateral damping for a stable ride. The LSM windings are
integrated with the suspension rails and excited by inverters located
along the guideway. The vehicle size and maximum speed can be varied
over a wide range to accommodate virtually all applications served today
by other guided transportation systems.

## Executive Summary {#executive-summary .unnumbered}

The U.S. DOT Federal Transit Administration (FTA) launched an Urban
Maglev Project in 1999 in order to create designs suitable for urban
transit. MagneMotion, EarthTech, TPI Composites and others formed a team
and, with cost sharing support from FTA, have developed an urban maglev
system called *M3* that is suitable for a Maglev People Mover (MPM).
This is the Final Report for the work completed to date. It provides an
overview of the system with detailed discussion of the design of the
suspension, propulsion, guideway, control system, and vehicle. It also
describes the experimental measurements conducted on the demonstration
prototype and provides applications examples, cost estimates and ongoing
development plans.

The *M3* system was designed with a system approach focused on providing
cost effective, fast, safe and environmentally friendly travel in an
urban environment. Features of *M3* are:

-   Small, lightweight vehicles operate at speeds up to 60 m/s (134 mph)
    with accelerations up to 0.2 *g*;

-   A guideway based control system with Linear Synchronous Motor (LSM)
    propulsion allows short headway for capacities to 12,000 passengers
    per hour per direction;

-   Permanent magnets provide key magnetic forces with high efficiency
    and a magnetic gap of 20 mm;

-   Lightweight guideways provide good ride quality at minimum cost.

Conventional high speed maglev designs, such as Transrapid with its
magnetic gap of 10 mm and top speed of 120 m/s (268 mph), require tight
dimensional tolerance and stiffness for the supporting beams in order to
achieve good ride quality. The use of a larger gap reduces guideway
tolerance requirements and a unique suspension design allows a minimum
horizontal turn radius of 18.3 m (60'). The permanent magnets provide
passive lateral guidance with active damping used to improve ride
quality. Onboard power requirements are so small that it is feasible to
use inductive power transfer to provide onboard power at all speeds so
there are no contacts between the vehicle and guideway and no exposed
third rail or catenary wires.

Maglev suspension and Linear Synchronous Motor (LSM) propulsion
technologies allow wayside communication and control and accurate
position sensing that remove the technical and safety hurdles often
associated with operating at short headways. All propulsion and control
components are on the guideway so there is no need for radio
communication of safety-critical information. Precise position sensing
and frictionless propulsion and braking allow short headways and high
capacity with small vehicles. The guideway is excited in short enough
blocks to provide average propulsion efficiencies of over 80%, including
all losses in the motor, electronics and power distribution system.
Additional energy savings are possible because with closely spaced
vehicles it is feasible to reuse energy regenerated by decelerating
vehicles.

A two-span guideway design was developed for the *M3* system using
traditional member geometry and materials (concrete and steel). Various
designs based on different construction methods were developed. Dynamic
vehicle-guideway interaction analyses were performed to assess ride
quality. Guideway deflections from live load, thermal distortion and
material creep and their effect on ride quality were considered.
Excellent ride quality was achieved using very light beams. The
estimated cost of the proposed *M3* guideway is less than the guideway
cost for other APM systems and much less than the cost of competing
maglev designs. Detailed cost analysis indicates that a long dual
guideway can be constructed for less than 10 million dollars per mile,
exclusive of land and station cost.

Vehicle weight reduction is one of the top three priorities along with
cost and reliability. The composite vehicle has a weight at least 30%
less than for an aluminum body vehicle. Manufacturing processes allow
for a 100% composite body that eliminates any composite/steel interface
typically found in other vehicles. The composite sandwich construction
also provides good insulation properties and is superior to metal
construction at damping vibration and noise. The baseline vehicle is 10
meters long and capable of carrying 24 people seated and 8 standees *or*
20 people seated and 20 standees *or* 32 people seated with no standees.
The empty vehicle weight is 5.5 tonnes and the maximum loaded vehicle
weight is 8.5 tonnes. The use of light vehicles has a major impact on
the cost of the guideway and propulsion system and leads to reduced
energy consumption.

The *M3* system design achieves high throughput with many small
lightweight vehicles operating in clusters. The vehicles within a
cluster operate with headways as short as 4 seconds but inter-cluster
headway is large enough to allow stopping in the clear distance ahead.
This cluster-based operation is the key to achieving high throughput
with small vehicles, analogous to the way highways provide high
throughput with small vehicles. The use of smaller vehicles results in
shorter wait times than larger vehicles at equivalent throughput,
especially at times of low demand. It also allows more flexible
scheduling without the need for all vehicles to stop at all stations.

An accurate, inductive position-sensing system coupled with a
wayside-based control system allows for the sharing of vehicle
information over a reliable, hard-wired link. Knowledge of the precise
position of all vehicles and the ability to apply consistent thrust in
all weather conditions greatly facilitates the implementation of a
short-headway control system. The control system for *M3* was developed
to meet the goals of safety, reliability, efficiency, flexibility, and
effective fault handling. It uses the concept of a 'target', or planned
stopping point. Each motor controller is responsible for allocating and
releasing movement permissions for targets within its borders, and
utilizes 'brick-wall' inter-cluster headways and 'safe-follower'
intra-cluster headways. This kind of operation allows for a level of
safety similar to that of larger trains operating with brick-wall
control. Use of small vehicles and systems that employ precise position
sensing can reduce transportation capital costs and energy consumption
simultaneous with decreases in average travel time and life cycle cost.

A demonstration prototype was constructed and detailed measurements
confirmed that our computer modeling and simulation provide accurate
predictions of performance. The vehicle required only a few watts for
levitation and the propulsion system is more efficient than most rotary
motor propulsion systems.

Four application examples were worked out in enough detail to confirm
that for a variety of applications it is possible to achieve average
travel times much lower than with conventional transit and in many cases
the advantage is more than a factor of two. Detailed cost calculations
confirm that even with the improved performance the installation and
operating cost is less than half of that for typical wheel-based
designs.

# Introduction

The design of the *M3* system has focused on the components that
contribute most to performance and cost*. M3* was designed with specific
objectives for improving on conventional guideway-based transportation
technologies and strategies for realizing the objectives.

-   *Decrease travel time by a substantial amount.*

> Allow speeds up to 605 m/s (134 mph), acceleration and braking up to 2
> m/s^2^, short average waiting time and reduced dwell time.

-   *Decrease operating cost by at least a factor of 2.*

> Reduce labor and maintenance costs and use less energy.

-   *Reduce guideway construction cost*.

> Reduce guideway weight by reducing vehicle weight and matching the
> guideway to the vehicle.

-   *Reduce environmental impact.*

> Reduce noise, guideway size and energy consumption.

-   *Create an improved ElectroMagnetic Suspension (EMS).*

> Use permanent magnets with a 20 mm magnetic gap and make each magnet
> contribute to lift, guidance and Linear Synchronous Motor (LSM)
> propulsion.

-   *Provide excellent ride quality.*

> Pay careful attention to guideway and vehicle design and take
> advantage of the distributed and non-contacting nature of maglev
> forces.

-   *Create a very safe transportation system.*

> Use a dedicated guideway, vehicles that cannot derail, linear motor
> propulsion that does not depend on friction, and totally automated
> operation.

A key feature that drives the *M3* system concept is the use of small
and light vehicles operating with short headway. The light weight
contributes to reduced guideway cost and the small size, in conjunction
with short headway, reduces wait time and allows station-skipping
operation. MagneMotion's objective is to develop and demonstrate an
urban maglev system with the following attributes:

-   Electromagnetic suspension (EMS) system that uses the same permanent
    magnet field for propulsion, suspension, braking and guidance.

-   Goal of \$25M per mile of dual guideway excluding vehicles and
    stations

-   Multi-vehicle control with headways as short as 4 seconds.

-   Operational speeds up to 60 m/s (134 mph).

-   Horizontal turns with a minimum radius of 18.3 m (60').

-   Vertical turns with a minimum radius of 300 m (1000').

-   Ability to climb and stop on grades of up to 18%.

-   Vehicle bank angles of 18º using a combination of guideway
    superelevation and vehicle tilt mechanisms.

-   Mechanical switching.

This report is organized as follows:

-   Introduction

-   Overview of system design

-   Discussion of the major subsystems

    a.  Magnetic suspension and guidance

    b.  Linear synchronous motor propulsion

    c.  Guideway design and manufacture

    d.  Vehicle attributes

    e.  Control system design and operation

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-   Description of a demonstration prototype and its performance

-   Examples of four applications

-   Cost estimates for a baseline design

-   Continuing development plans and activities

-   Conclusion

# Overview

In the last 35 years maglev has changed from an engineering curiosity to
the basis for commercial installations, one now operational in China and
one soon to be operational in Japan. German and Japanese efforts over
many years have demonstrated maglev's potential for safe, fast and
economically viable transportation but potential users have not been
impressed enough to install a major commercial system until very
recently. The lack of commercial support has been partly due to emphatic
statements by critics (there are also many supporters) from academia,
industry and the government that maglev is too expensive in comparison
with other types of guided transportation. These criticisms are not
based on valid technical arguments but are akin to the criticisms of
railroads that were made in the early 1800s when the "smart money" was
being invested in canals. Unfortunately, maglev enthusiasts have not
helped the cause by often focusing more on the technology than on what
it can deliver to the user.

A principal problem with past maglev efforts has been an excessive
emphasis on speed and technology without taking a system approach to
solving a transportation problem. With this in mind, MagneMotion has
stressed the system approach and examined all aspects of the problem of
providing high quality and cost effective transportation with maglev by
taking advantage of recent advancements in enabling technologies. For
U.S. applications MagneMotion believes a key market for maglev today is
in the low and middle speed region now dominated by light rail, rapid
transit, commuter rail and all versions of Automated People Movers
(APM). The MagneMotion Maglev system, called *M3*, is currently focused
on speeds up to 60 m/s (134 mph) but with minor modifications the system
could compete with any guided system including ones with both lower and
higher speed capability.

A fundamental property of magnetic structures, called Earnshaw's
Theorem, is that no static configuration of magnets can be levitated so
as to be stable in all degrees of freedom. It is possible to be stable
in all but one dimension, so it is possible to have a magnetic
suspension stable in the vertical direction but then it must be unstable
in a lateral direction. Such structures have been proposed but they tend
to be heavier and more complex than if electronic control is used to
stabilize the suspension in the vertical direction. The vertical
stabilization approach to ElectroMagnetic Suspension (EMS) has now been
proven to be suitable for operation over a wide range of speeds. For
example, the new Shanghai Transrapid maglev installation uses this
approach and is now carrying passengers at speeds up to 430 km/h (267
mph), 34% faster than the fastest high-speed trains in operation today.

Historically, the major disadvantage of EMS is the need to use magnetic
gaps no larger than about 10 mm. MagneMotion has overcome this
disadvantage by using permanent magnets in conjunction with control
coils to allow a magnetic gap of 20 mm. Although some ElectroDynamic
Suspension (EDS) designs feature larger gaps, it is not clear there is a
need for gaps greater than about 20 mm at speeds that are of interest
for urban transportation.

This report gives a description of *M3* as it exists at this time.
Although the design is expected to evolve over the next few years it is
unlikely to change in any major way. This report can be used to assess
the potential merits of *M3* for specific applications.

Figure 2.1 shows a 3D view of a preliminary version of the baseline
vehicle and some of its features.

![](media/image4.png){width="4.375in" height="3.4243055555555557in"}

[]{#__RefHeading___Toc89856168 .anchor}Fig. 2.1. Preliminary vehicle and
guideway design.

Following are the key performance specifications that were the basis of
the design:

-   Speeds up to 60 m/s (216 km/h, 134 mph).

-   Acceleration and braking up to 2 m/s^2^ (4.4 mph/s).

-   Headways as short as 4 seconds when operated in clusters.

-   Capacity up to 12,000 passengers per hour per direction (pphpd).

-   Horizontal turn radii of 18.3 m (60') and vertical radii of 300 m
    (984').

-   Target cost of \$25 million per mile excluding vehicles, stations
    and land.

-   Minimum environmental impact with reduced noise and guideway size.

Figure 2.2 shows a cross-section of the guideway beam and the vehicle.
The permanent magnets on the vehicle provide lift, guidance and act as
the field for Linear Synchronous Motor (LSM) propulsion. Pivoting magnet
pods allow short turning radii in both horizontal and vertical
directions. Control coils wound around the magnets stabilize the
suspension and adjust the nominal magnetic gap to the value that
minimizes power requirements for the control. Windings in the guideway
are excited by inverters located along the guideway and provide
controllable thrust for acceleration, cruise and braking. The secondary
suspension on the vehicle provides improved ride quality but can be
omitted for lower speed operation.

![](media/image5.png){width="6.0055555555555555in"
height="4.024305555555555in"}

[]{#__RefHeading___Toc89856169 .anchor}Fig. 2.2. Cross-section of
guideway beam and preliminary vehicle suspension.

The design of the *M3* system has focused on the components that
contribute most to performance and cost with a particular focus on
subsystems that have unique features: permanent magnet EMS suspension,
LSM design and manufacture, guideway beams, vehicle suspension and
control systems. In order to create confidence in the basic design a
demonstration prototype has been constructed and tests to date are very
encouraging. Future plans call for extending the test track and building
a high-speed test track as a prelude to installing a commercial system.
A description of our prototype is given in Section 9 and a summary of
our continuing development plan is given in Section 11.

# Electromagnetic suspension and guidance

A key design objective was to create a suspension that is suitable for
low to moderate speeds with frequent station stops, allows vehicles to
make small radius turns in both the horizontal and vertical directions,
and is suitable for use with small vehicles. Members of the MagneMotion
maglev team have had considerable experience with both ElectroMagnetic
Suspension (EMS) and ElectroDynamic Suspension (EDS). A careful review
of the merits of each led us to pick the EMS design for the following
reasons:

-   Ability to levitate at all speeds.

-   No need for high propulsive force at low speed to overcome magnetic
    drag.

-   No need to shield the passengers from unacceptably high magnetic
    fields.

-   Reduced cost for a complete system.

Following is a discussion of the *M3* features that contribute to
decreasing cost and increasing performance.

## Permanent magnet EMS

A key feature of the *M3* suspension is that every permanent magnet on
the vehicle contributes to suspension, guidance and propulsion. This is
analogous to the way every railroad wheel provides suspension and
guidance and plays a key role in propulsion and braking. Without this
3-way combination there is added cost and complexity. For example,
Transrapid uses one set of electromagnets to provide both lift and a
field for an LSM but requires separate steel rails on the guideway and a
separate set of feedback controlled electromagnets on the vehicle to
provide guidance. The Japanese low speed HSST and Korean Maglev designs
provide lift and guidance with a single electromagnetic structure but
require a separate aluminum reaction rail on the guideway and Linear
Induction Motor (LIM) primary on the vehicle to provide propulsion. For
*M3* the integration of these three functions allows the vehicle magnet
arrays to be mounted on pods that can rotate like wheel bogeys to allow
sharp turns in both the horizontal and vertical directions.

Figure 3.1 shows a pod with permanent magnets attracted upward to a
laminated steel suspension rail. Control coils around the magnets are
used for stabilization and windings integrated into the suspension rails
are excited by wayside power inverters to provide propulsion.
Half-length magnets at the ends of the pod equalize magnetic flux and
mitigate cogging. This drawing shows propulsion windings wound on teeth
on a guideway rail and suspension control coils wound around permanent
magnets on a vehicle pod.

[]{#__RefHeading___Toc89856170 .anchor}![](media/image6.wmf)Fig. 3.1. A
vehicle's magnet pod attracted upwards to a suspension rail.

Coils wound around the magnets are excited from a controller that uses
gap and acceleration sensors to control current in the coils. This
stabilizes the magnetic gap at that value which provides a match between
vehicle weight and permanent magnet force. Ideally it would take
negligible power to stabilize the suspension and in practice the power
requirement is dramatically less than it would be if the entire
suspension force were provided by electromagnets alone. When the vehicle
is stationary the required control power will be only a few watts and at
operational speeds simulations show it to be on the order of 100 W per
Mg of vehicle mass. For comparison, Transrapid uses electromagnets for
suspension and they require 1,000 W per Mg of vehicle mass for a
suspension with a magnetic gap of only 10 mm, and require substantial
additional power for guidance.

The use of permanent magnets allows the use of a magnetic gap of 20 mm
with a corresponding reduction in guideway tolerance requirements. The
vehicle mass is estimated to be 5.5 Mg empty with a load of up to 3 Mg
depending on the number of passengers. The suspension controller will
adjust the magnetic gap to minimize control power and thus the gap will
vary 23 mm for an empty vehicle to 17 mm for a fully loaded vehicle.

## Lateral guidance and damping

The suspension system must also provide lateral forces to guide the
vehicle and resist lateral forces due to turns and wind. An important
feature of *M3* is the way the magnets that provide suspension forces
also provide guidance forces. If the vehicle is displaced laterally
there will be strong restoring forces created by the tendency of the
magnets to align themselves with the steel suspension rails on the
guideway. By using a magnetic gap that is 25% the width of the
suspension rails it is possible to provide passive guidance with a
lateral guidance force up to 40 % of the vertical lift force. Figure 3.2
shows the results of a 3D Finite Element Analysis (FEA) of a 3.25 meter
long pod (12 full size magnets and 2 half-magnets at the ends) designed
to support 25% of a baseline vehicle. The plot shows the magnetic gap
and lateral guidance force *F~z~* as a function of lateral displacement
*z~d~* for a nominal load. With a 20 mm gap there is 16.7 kN of lift
force when there is no lateral displacement. With a lateral displacement
of 40 mm the magnetic gap would drop to 14.7 mm (to maintain the
vertical force) and there would be a lateral restoring force of 0.33 g =
5.5 kN. Vertical and lateral skid-pads will be provided to deal with
extreme forces, such as might happen during an earthquake.

![](media/image7.wmf){width="5.995833333333334in"
height="4.0465277777777775in"}

[]{#__RefHeading___Toc89856171 .anchor}Fig. 3.2. Vertical gap and
lateral force vs. lateral displacement.

Although the suspension is passively stable for lateral motion, there is
very little damping so other means must be provided to prevent excessive
lateral motion. We have achieved active lateral damping and this is
described in Section 8 as part of the discussion of our demonstration
prototype.

## Horizontal and vertical turns

Creating a maglev system that can negotiate tight turns has been a
challenge to all maglev designers. In a cost-effective design the
magnetic force must be distributed over a large area but for making
tight turns the suspension magnets must be articulated so that they
follow the turn. The *M3* mechanism for doing this is shown in Figs
3.3-4. This preliminary design is for a 36-passenger (24 seated) vehicle
that can negotiate horizontal turn radii of 18.3 m (60') and vertical
turn radii of 300 m (984'). Improved designs are being studied.

![](media/image8.wmf){width="5.25in" height="3.2104166666666667in"}

[]{#__RefHeading___Toc89856172 .anchor}![](media/image9.wmf)Fig. 3.3.
Suspension mechanism showing pod pivoting for turns.

[]{#__RefHeading___Toc89856173 .anchor}Fig. 3.4. Top view of suspension
system.

# Linear Motor Propulsion

## Comparison of synchronous and asynchronous linear motors

Maglev developers have universally adopted the linear electric motor as
the propulsion system of choice for maglev. There are two types of
linear motor that are currently being used for commercial designs:
Linear Induction Motor (LIM), also called a linear asynchronous motor)
and Linear Synchronous Motor (LSM).The only practical version of the LIM
is one that has the propulsion windings on the vehicle, the "short
primary" design. This design has some advantages:

-   A power inverter is required for each vehicle motor, but the total
    cost of inverters for a complete system is reduced.

-   The guideway portion of the LIM consists of an aluminum sheet on
    steel backing and this is less expensive than an LSM stator.

The disadvantages of the LIM include:

-   The vehicle weight is increased by at least 20% because of the
    onboard propulsion equipment.

-   It is very costly in weight and efficiency to operate with a LIM
    magnetic gap more than about 10 mm and thus guideway tolerances are
    more critical.

-   It is necessary to use sliding contacts to transfer all of the
    propulsion power to the vehicle or, at much greater cost, to use
    inductive power transfer.

-   The motor efficiency is reduced, both because the motor is less
    efficient and because the vehicle is heavier and requires more
    propulsive thrust.

The only practical version of an LSM is one that has the propulsion
winding on the guideway, the "long primary" design. This has a number of
important advantages:

-   The motor can use the same magnets as the suspension and thereby
    reduce vehicle cost and weight and increase efficiency.

-   The magnetic gap can be larger.

-   The vehicles are lighter so less propulsive power is required.

-   There is no need to transmit propulsive power to the vehicle.

-   The propulsion and control equipment is all on the guideway so
    communication is more robust, control is simplified and regenerative
    braking is easier to achieve.

The disadvantages of an LSM include:

-   Higher cost for guideway-mounted LSM motor windings and wayside
    power inverters.

-   Precise position sensing is required.

Virtually all high-speed maglev designs use an LSM for propulsion. Early
versions of Transrapid used the LIM but starting with TR05 in 1975 they
switched to the LSM. The Japanese high-speed maglev developers have
always used an LSM. The Japanese HSST and Korean designs use a LIM but
they have limited speed capability. A superficial analysis of cost might
suggest that LIM propulsion is less expensive but when all of the costs
associated with the negative aspects are considered it is likely to be
more expensive for a complete system. The dramatic reduction in the
onboard power requirements is also a strong incentive for using an LSM.
For *M3* with light vehicles and a 20 mm gap the LIM is not a viable
alternative. Details of the *M3* LSM design are discussed in this
section.

## The tradeoff between cost and performance

An LSM can be designed to give almost any desired performance, but
increased performance implies increased cost. The design problem is to
find that level of performance that is most cost effective. For example,
we could use a smaller LSM that produces less thrust and is less
expensive, but then vehicle acceleration is reduced so travel time is
increased and we lose many of the advantages of a higher top speed.

For standing passengers it has been generally accepted that an
acceleration of 1.6 m/s^2^ is an upper limit for safe operation. Since
an urban vehicle stops frequently and often has standees it was decided
to limit acceleration to this value. In order to be able to accelerate a
fully loaded vehicle at 1.6 m/s^2^ it is necessary to have more thrust
than is necessary for the same acceleration for a nominal load. Thus the
*M3* design calls for an acceleration capability of 2 m/s^2^with a
nominal load. This also allows a maximally loaded vehicle to maintain an
acceleration of 1.6 m/s^2^ up to a higher speed.

In many examples that have been considered there are sizable regions
where it is not necessary to provide rapid acceleration or deceleration
and in these regions it is possible to reduce the propulsive power with
a resulting saving in cost. The reduced propulsive power also implies
reduced braking capability from the LSM, but this can be made up by
other means, as will be discussed later.

## Block length optimization

An LSM winding on the guideway is divided into sections called blocks
and each block is excited by a wayside inverter to provide thrust. An
important constraint is that only one vehicle can be in one block at one
time. At low speeds and high acceleration we would like to have low
winding resistance in order to have high efficiency with minimum
inverter rating. At high speeds and moderate acceleration, the power
loss in winding resistance is relatively low, but the winding inductance
plays a major role in limiting performance and leads to a higher VA
rating on the inverters. In order to achieve acceptable values of
winding resistance and inductance it is necessary to limit the length of
propulsion winding that is excited at any time. For *M3* a good choice
of block length is in the range 12 to 72 meters depending on speed and
acceleration requirements. In order to simplify installation it is
convenient to match the block length to the guideway pier spacing. In a
later section it will be shown that a good pier-to-pier spacing is 36
meters, so this has been chosen as the nominal block length. Near and in
stations a 12 or 18 meter block length will be used and in regions where
constant speed is the norm the block length may be as long as 72 meters.
The combination of block length and inverter size should be carefully
chosen so as to provide desired performance at the lowest cost.

## Propulsion power system and inverter design

The inverter changes the DC bus voltage into variable amplitude,
variable frequency, 3-phase AC for activating the windings on the
guideway. The inverter is the key component in the power system and
there are a number of issues that must be addressed if reliable and cost
effective operation is to be maintained over the complete speed and
force range.

### Cost reduction techniques

The principal means of reducing power system cost are:

-   Develop an inverter that uses state-of-art design and is matched to
    the application

-   Use sub-block switching with longer LSM blocks so as to reduce the
    number of inverters required

-   Adapt the DC power source and power distribution to the inverter
    input and output requirements

-   Develop tooling and procedures to reduce installation cost.

The optimum design for an application will depend upon many things,
including design considerations discussed here and the latest evolution
in materials, components and design methodology. Here are some factors
to keep in mind when adapting *M3*;

-   The requirement for high thrust at low speeds is the operating
    condition that dominates the inverter design problem. Low speed
    operation puts maximum thermal stress on the components and
    necessitates using larger components than might otherwise be needed.
    The inverter must be sized for high-speed operation, but at high
    speeds the currents and switching losses are lower so there is less
    thermal stress on components.

-   Inverters supply AC currents to the windings and for high power
    inverters it is essential to use switching frequencies in the middle
    of the audio spectrum. It may turn out that special features must be
    added in order to reduce audio noise to acceptable levels but these
    features can be added later if the need arises.

-   Power system cost is expected to be 5 to 5.5 million dollars per
    dual-guideway mile with the higher value for systems with higher
    capacity. Increasing the maximum speed has relatively little impact
    on system cost.

-   A major component of the power system cost is for installation of
    inverters, switches and cables. A major effort will be made to
    simplify the installation.

-   The *M*3 propulsion system consumes substantially less energy per
    passenger mile than any conventional transit system in spite of the
    higher operating speed.

At speeds above about 23 m/s (51 mph) the inverter can be operated at
maximum output with relatively low temperature rise for the key
components. At speeds below 1 m/s (2.2 mph) the inverter output
frequency is less than 2 Hz and it is necessary to use relatively rapid
switching to create an approximation to the desired sinusoidal current
waveforms. The thermal time constants of the semiconductor devices are
so short that for these speeds the currents must be limited because of
instantaneous power dissipation constraints, which limit the ability to
distribute the dissipation equally over all modules. Perhaps more
important, at these very low speeds the semiconductor devices are
subject to thermal cycling that is known to have a deleterious effect on
device longevity. At speeds between 1 and 23 m/s the devices are subject
to substantial thermal stress but with a well-designed inverter the
device junction temperatures are well below maximum limits.

The cost of a propulsion system can be reduced by using one inverter to
power several sub-blocks with relatively simple thyristor switches used
to determine which sub-block is activated. Several sub-block switching
strategies were considered and it is possible to reduce inverter-related
cost by up to a factor of two with the design details depending on the
application. For the baseline design we assume there is an average of 1
inverter for every 2 blocks and each inverter includes a 2-way, 3-phase
thyristor switch.

### Inverter design and performance

A number of manufacturers sell relatively low cost IGBT (Insulated Gate
Bipolar Transistor) power modules that contain most of the high power
components for a 3-phase inverter. Use of these standard modules reduces
system cost while allowing wide flexibility in the control. MagneMotion
has spent many years refining the design of LSM inverter controllers and
the use of these controllers in conjunction with standard power modules
has led to a dramatic reduction in inverter cost as compared with the
use of commercially available inverters.

The *M3* controllers use Digital Signal Processors (DSP) to process
signals from the position sensors and control the power device switching
according to the required output with the highest possible efficiency.
At low speed the power devices switch at a frequency of a few kHz in
such a way as to produce nearly sinusoidal currents with the correct
frequency, phase and current for the required force and speed. At high
speeds the switching is synchronized with the propulsion frequency and
phase control is used to control thrust. This combination of
asynchronous and synchronous switching allows the controller to drive a
highly inductive load over a wide speed and force range without
requiring an excessive Volt-Ampere rating for the power modules.

Figure 4.1 shows contours of constant inefficiency in the force vs.
speed domain for a typical *M3* design. For this example the maximum
force is 7 kN up to a speed of 27 m/s (60 mph) and then the power is
limited to 189 kW for speeds up to 45 m/s (101 mph). The dissipation is
primarily due to LSM winding resistance loss and the maximum power limit
is primarily due to winding inductance. For this example the full 189 kW
output is available up to 60 m/s (134 mph) and this is the maximum
operational speed without any changes in inverter design. The
inefficiency in the plot is defined as the ratio of power dissipated to
power delivered and is only for the motor. For a typical vehicle
mission, including the losses in inverters and the DC power system, the
average inefficiency is about 12 % giving a propulsion efficiency of
88%. The propulsion efficiency is higher than for most wheel-based
transit systems and, as discussed elsewhere, the lighter vehicles leads
to additional energy savings.

![](media/image10.wmf){width="5.99375in" height="2.8944444444444444in"}

[]{#__RefHeading___Toc89856174 .anchor}Fig. 4.1. Contours of constant
inefficiency in the force vs. speed domain.

### Acoustic noise

If the LSM propulsion were for a steel-wheeled vehicle the noise
produced by electromagnetic forces would be masked by wheel and gear
noise, but for maglev there is a much higher expectancy that noise be
minimal. Some audible noise will always be produced by an LSM even if
the waveforms were perfect sinusoids at the synchronous speed. With a
switch-mode controller other frequencies are created, most notably
harmonics of the propulsion frequency and frequencies generated by
switching that is not synchronous with the propulsion frequency. In
order to control thrust at low speed it is necessary to use switching at
frequencies on the order of 1 to 3 kHz, frequencies that are in a
sensitive region of the audio spectrum. There are steps that can be
taken in the mechanical construction to minimize audible noise, but
ultimately it may be necessary to use additional electronic hardware in
order to achieve acceptable levels of noise. More work is needed to
quantify this problem.

## Power distribution and control

Figure 4.2 shows a typical power distribution design. The electric
utility provides 3-phase power to a rectifier station that then delivers
DC power to a bus connecting the wayside inverters. The spacing between
Rectifier Stations is determined by vehicle density and acceleration
profiles but will typically be in the range 5 to 10 km (3.2 to 6.4
miles). For the baseline design a spacing of 8 km (4.97 miles) is
assumed.

![](media/image11.wmf)

[]{#__RefHeading___Toc89856175 .anchor}Fig. 4.2. Power distribution
system.

The baseline design uses a 3-wire DC bus to transmit power at +900 VDC
and -900 VDC with a 0 VDC wire connected to ground at frequent
intervals. The DC bus and communication cables are installed in the
beams on one side of the guideway. The port motor is powered from +900 V
and the starboard motor is powered from -900 V, or vice versa. Since the
currents in the two motors are nearly equal the majority of the power is
distributed at the 1,800 V level; this high voltage allows longer
distribution distances than are commonly used for rapid transit or
light-rail. Relatively inexpensive 1,700 V IGBT power devices are now
available and these will operate reliably on a 900 VDC bus. The DC bus
is designed to carry 750 kW up to 4 km (2.49 miles) in each direction
with a typical distribution efficiency of greater than 97% at full load.
The rectifier station and cables are designed to provide 50%
over-capacity for several minutes in order to deal with fluctuations in
power demand. This baseline design is based on 4 vehicles per mile of
dual guideway, each consuming 75 kW average, including onboard power
which is derived from the same DC bus. In order to increase the number
of vehicles we could add a second set of DC power cables in the second
guideway, with the two sets of DC cables interconnected at the inverter
stations, and increase the rectifier power rating.

The inverters not only provide power for accelerating vehicles, they are
also used to decelerate the vehicles and deliver the vehicle kinetic
energy back to the DC bus so it can be used elsewhere in the system. The
use of regeneration can reduce total energy consumption by up to 40 %
for a typical urban application, as will be seen in the next section.

Since only one vehicle can be present in a block at a time, inverter
spacing must be short enough to deal with the minimum expected headway.
For 4-second headway at 45 m/s we could, in principle, use one inverter
to power a block that is almost 180 meters long. In a typical design we
will use an inverter for every block near and in stations and an
inverter for every other block between stations. This is done by means
of sub-block switching with 3-phase thyristor switches used to determine
which block is excited. With this scheme, and two blocks per inverter,
vehicle headway can be as short as 120 meters when the block length is
36 meters. After the system is constructed if higher capacity is
required the switches can be removed and a separate inverter used for
each block.

## Performance simulation

Figure 4.3 shows distance, velocity and power plots for a trip of 3.2 km
(2 miles). It is assumed that the vehicle accelerates at a rate that is
the minimum of 1.6 m/s^2^ and a rate limited by the maximum available
thrust from the motor for a nominal vehicle mass of 7 Mg. For
deceleration the LSM is able to sustain a uniform 1.6 m/s^2^ for almost
the entire stopping time. It is assumed that there are no grades that
prevent the acceleration or speed from being sustained. The model used
for the plots in Fig. 4.3 includes the effects of aerodynamic drag,
winding resistance and power system inefficiency.

![](media/image12.wmf){width="5.908333333333333in"
height="4.893055555555556in"}

[]{#__RefHeading___Toc89856176 .anchor}Fig. 4.3. Distance, speed and
power profiles for a 3.2 km (2 mi) trip.

For the 3.2 km trip in Fig. 4.3 if the dwell time is 20 seconds the
average speed is 27 m/s (60 mph). In order to estimate travel times for
other trip lengths assume the speed is 45 m/s for the entire trip but
with a time penalty of 30 seconds for every stop plus a dwell time,
typically 20 to 30 seconds, for every stop. If the trip length is less
than 1.6 km (1 mile) then the vehicle never reaches maximum speed so
extra time is required.

Power consumption is: 412 kW peak; 113 kW cruise; 65 kW average with
full use of regenerated power and 112 kW if braking energy is dumped in
resistors without reuse. For this example regeneration provides a 42%
saving in propulsion power cost. The savings would be less for a longer
trip and more for a shorter trip.

In some cases more energy is being regenerated than can be used in a
useful way and in this case the power must be dumped into resistors. It
is possible to add a power dumping facility to each rectifier station,
but this is unnecessary. There is always at least one inverter not being
used for every inverter that is being used and these unused inverters
can be used to dissipate power in the propulsion windings where there is
no vehicle. This method of braking is particularly useful when, due to
an emergency, it is desirable to stop every vehicle in the system in the
shortest possible time. Preliminary calculations show that this can be
done without the need for separate braking resistors. For emergency use
braking resistors will be installed in rectifier stations but they do
not need to be rated for continual use.

All electrically propelled transit systems create problems for the
electric utilities because of the large and rapid fluctuation in power
consumption. One advantage of using small, closely spaced vehicles is
that starting times can be controlled to minimize the peak excursions.
Simulations show that with only minor control of when a vehicle leaves a
station it is possible to make full use of regenerated energy and reduce
the peak power excursions by a large factor. More detailed simulations
are planned when the system design is complete.

A problem all transit systems must address is the need to deal with
electric power failures in a safe and effective way. Using battery
backup of the inverter controllers so that they can maintain control
solves the safety aspects of power failure. The controllers would cause
the vehicles to brake and the braking energy would maintain the DC bus
voltage until nearly all vehicles are stopped, at which point
eddy-current and/or mechanical brakes would be used. The least expensive
way to provide passenger egress in the event of power failure is to
install a modest size standby power source in every rectifier station. A
100 kW DC generator, or possibly a standby battery, is adequate to
provide some power for onboard vehicle use while also moving the
vehicles, one by one, to a station where people can be unloaded. Such an
emergency power source would add very little to the system cost but
provide an important safeguard.

It is important that the complete power system be simulated in
substantial detail before the design is finalized in order to identify
potential problems with electrical transients and thermal behavior.
Simulations should also be done to ensure that normal component or power
system failure will not cause unreasonable consequences.

## Efficiency and energy consumption

For a transit system energy cost is quite significant, typically more
than 10% of operating cost. For *M3* it is estimated that for typical
usage the propulsion efficiency will be in the range 80-85%. This
includes all loss in the stator, inverter and power distribution system.
In evaluating efficiency there are several points to keep in mind:

-   The efficiency of the motor is very dependent on thrust and speed.

-   The ability to use regenerated energy can reduce energy costs by a
    large factor.

-   For urban applications a large fraction of the energy consumed is
    related to acceleration and deceleration, not cruising at constant
    speed.

-   The use of light vehicles and station-skipping control strategies
    can greatly reduce energy usage.

One of the best measures of efficiency is the energy usage per
passenger-mile of travel. From the plots of Fig. 4.3 we see that the
average power required is 65 kW for an average speed of 60 mph or 3.9
MJ/mile. Assuming a nominal load of 18 passengers this implies a
consumption of 217 kJ/pas-mi = 60 W-hr/pas-mi. In order to account for
energy for HVAC power usage and other factors, assume the actual
consumption is 100 W-hrs/pas-mi. Assuming electric power cost of \$0.12
per kW-hr, the energy cost is \$0.012 per passenger mile. For continuous
cruising at maximum speed the energy consumption is 62 W-hr/pas-mi,
almost the same as with the stop.

In order to compare *M3* energy consumption with that of other transit
systems we need to convert the energy to BTU/pas-mile. The theoretical
conversion is 1055 J/BTU or 3.412 BTU/W-hr. For comparison with other
modes we need to account for the 29% average efficiency of electricity
generation and distribution (see Table B.3 in the Transportation Energy
Data Book in the reference given following Table 4.1) so the appropriate
conversion factor is 11.8 BTU/W-hr. This example shows an energy
intensity of 1180 BTU/pas-mile and Table 4.1 shows how this compares
with energy consumption for various rail and bus modes.

Table 4.1. Comparison of energy usage of various transportation modes.

+---------------------+---------------+-------------+-----------------+
|                     | *Energy       | *Average    | *Energy         |
|                     | usage,*       | trip*       | Intensity,*     |
|                     |               |             |                 |
|                     | *10^12^ BTU*  | *length,    | *BTU/pas-mi*    |
|                     |               | miles*      |                 |
+---------------------+---------------+-------------+-----------------+
| *M3*                |               |             | 1,180           |
+---------------------+---------------+-------------+-----------------+
| Intercity rail      | 23.0          | 238         | 4,137           |
+---------------------+---------------+-------------+-----------------+
| Commuter rail       | 25.9          | 22.8        | 2,717           |
+---------------------+---------------+-------------+-----------------+
| Rail Transit        | 48.6          | 5.1         | 3,114           |
+---------------------+---------------+-------------+-----------------+
| Intercity bus       | 32.3          |             | 932             |
+---------------------+---------------+-------------+-----------------+
| Transit bus         | 91.6          |             | 4,125           |
+---------------------+---------------+-------------+-----------------+
| Certified air       | 2,599         | 842         | 3,968           |
| carriers            |               |             |                 |
+---------------------+---------------+-------------+-----------------+
| Autos               | 9,100         | 9.1         | 3,588           |
+---------------------+---------------+-------------+-----------------+

Data is taken from Tables 2.5,2.12-13, 9.2,9.12-14 in Transportation
Energy Data Book: Edition 23 (Oct. 2003, Oak Ridge National Laboratory,
available at www-cta.ornl.gov/data). Data is for 2001 except intercity
bus mode data is for 2000.

Care must be taken in interpreting Table 4.1 because of wide variations
within any mode. For example, the energy intensity for light rail varies
from less than 2,000 BTU/pas-mi for Newark to more than 8,000 BTU/pas-mi
for Cleveland. The conclusion is that *M3* has the potential to reduce
energy consumption to less than half that of other modes and, if people
will use maglev instead of a car or airplane the savings are even
greater. If an *M3* system were operated with the same maximum speed and
stopping frequency as intercity bus, *M3* would have essentially the
same energy intensity. In summary, maglev can offer significant energy
savings, particularly in comparison with the modes most used in the U.S.
today.

## LSM manufacturing

The design of the LSM suspension rails and winding has been completed
and we have studied several methods for installing the components at the
lowest possible cost. It is anticipated that we will manufacture the
lamination stack and coils for both straight and curved (i.e. standard
radius) sections of guideway as an environmentally sealed unit. The
stator will be mounted under the suspension rails. We are developing
improved ways of mounting the LSM stator to the guideway. Our effort has
concentrated on reducing the amount of alignment that has to be done in
the field.

# Guideway

The focus of the *M3* design effort was to keep the guideway beams as
small and light as possible without jeopardizing ride quality. The
resulting design is based on deflection considerations, and the strength
of the structures is far greater than is necessary so there is no
compromise with safety. The relatively small size of the guideway is
evident in the artist's rendition on the cover of this report. The pier
spacing is large and the beam cross-section small when compared with
virtually all other elevated transit systems. For new installation it is
believed that most urban maglev systems will use elevated guideways to
avoid the right-of-way access and safety problems of at-grade guideways
or the cost of tunnels. Maglev vehicles make no wheel or engine noise
and very little wind noise at speeds suitable for urban transportation.
Many of the objections to elevated guideways are ameliorated by the *M3*
design.

In some cases Urban Maglev will operate at-grade or in tunnels and in
these cases the beams can have a smaller height with more frequent
supports, but the design principles are the same. For example, a reduced
height beam could be mounted directly on railroad ties to replace rails
in a rapid transit retrofit.

Guideway cost is a dominant item so considerable effort has been made to
reduce cost by reducing size and weight. The following sections discuss
some of the key details of the guideway design.

## Beam design

With EMS designs the vehicles must either be supported by an overhead
rail or use a monorail type of construction with the vehicle wrapped
around the beam and magnets moving under the suspension rails. The
overhead design could be useful for indoor use, but is not considered
desirable for outdoor use because of the high cost of a support
structure and poor ride quality in the presence of high winds.

The MagneMotion guideway consists of beams mounted on piers spaced 36
meters apart. This spacing was determined by an iterative process that
considered the tradeoff in cost between using more piers and a lighter
beam vs. fewer piers and a heavier beam. An additional consideration is
a preference to use longer pier spacing because then there is less
visual impact. For comparison the new Shanghai Transrapid installation
uses a pier spacing of 24.8 meters but even with this shorter spacing
the beams have a mass of 190 Mg so a longer span is not practical. The
New Millennium extension of the Vancouver Skytrain uses 37 meter
spacing.

It would be possible to make the beam length equal to the pier spacing,
but there are major advantages of using a double-span beam. In this case
a double-length beam is supported in the middle with a rigid mount and
at the ends with a sliding mount. When the temperature changes the beam
will change length and slide on the end mounts and enough space is
allowed so that adjacent beams never touch. The distributed nature of
the suspension magnets allows gaps of 20 mm to be easily bridged. As
compared with a single-span beam with the same pier spacing, the
double-span beam offers a 30% reduction in static deflection as well as
a reduction in dynamic deflection, even though the lowest resonant
frequency is the same. In some cases it may be necessary to use
single-span beams and then a somewhat large section will be used to
maintain adequate stiffness.

Three alternate sections have been studied for the guideway beams: a
steel box girder, a concrete box girder, and a hybrid design that uses a
concrete box girder with a composite steel top plate. The sections for
concrete and steel are shown in Figure 5.1 for the case of a 1.7 meter
gauge or distance between support rail centers. The top plate used for
supporting the rails is only schematic with details of the method of
attachment still to be completed. Alternatives being studied include
cross-ties, similar to a railroad, and a composite plate with integrated
attachment points. The hybrid design is similar to the concrete design
except that steel cross-ties used to support the suspension rail are
replaced by a solid steel top plate bonded to the concrete beam. With
the hybrid design the steel that supports the rails also contributes to
reducing guideway deflection and increasing the resonant frequencies.

![](media/image13.wmf){width="3.875in" height="2.6256944444444446in"}

\(a\) Concrete (b) Steel

[]{#__RefHeading___Toc89856177 .anchor}Fig. 5.1. Alternate beam section
with dimensions in meters.

For all of the alternates a two-span continuous girder configuration is
used. Horizontal restraint is provided at the interior pier with fixed
bearings in the case of the steel alternate, and with a monolithic
connection in the case of the concrete alternate. The monolithic
connection will use the additional stiffness of the pier to increase the
overall stiffness somewhat, and is an economical means of making the
connection.

These sections were incorporated into single and double guideway
designs. The geometry of the design is dictated by dimensional
constraints on the beam, and its connection at the column, which are
imposed by the attractive maglev system. A relatively narrow girder is
required because of the need for the magnetic pods to wrap around and
under its edge. In addition, ride-quality considerations and deflection
tolerances suggest a relatively deep girder. Together these two
requirements result in a fairly deep narrow girder for which stability
must be provided by external diaphragms. Since 4 meters (i.e. from beam
center to beam center) will separate the two double-track guideway
beams, intermediate diaphragms between the girders are not desirable
(though they may be necessary in seismic zones). Stability is therefore
provided by "outrigger" diaphragms at the bearings, or by a monolithic
connection to the column. Diaphragms must be kept out of a zone of
roughly half a meter below the top of the girders in order to allow the
magnetic pods to pass.

## Beam statics and dynamics

Guideway beams are designed on the basis of stiffness, not strength.
Almost any design that gives good ride quality will be capable of
carrying much higher loads than the maglev vehicles will create. The
extra strength means, for example, that heavy maintenance or rescue
vehicles could safely operate on the guideway if they operated at
reduced speed. Since the key issue is ride quality, the important
parameters are the guideway deflection under static and dynamic loads
and due to thermal deflection and creep. Since beam cost is very nearly
proportional to weight, the problem is to design a beam that is as light
as possible but provides good ride quality.

For this discussion static deflection is defined as the deflection of
the center of the beam when vehicles move across it at a low speed.
Dynamic deflection is defined to be the extra deflection that occurs
because of resonances in the beam. Although the beam has an infinite
number of resonant frequencies, only the first one or two contribute
significantly to vehicle ride quality. The peak dynamic deflection can
never exceed the peak static deflection but it can have a major effect
on ride quality. We can use precamber of the beam to compensate for
nominal vehicle mass but cannot use it to compensate for dynamic
deflection.

## Comparison of steel and concrete beams

This discussion assumes beam properties given in Table 5.1 for a 1.5
meter gauge. We now believe a 1.7 m gauge is a better choice and Fig.
5.1 is based on this wider gauge. The main effect of increasing the
gauge is to make the beam stiffer and provide a wider base for
supporting the vehicle on turns.

Table 5.1 Properties of guideway beams for a 1.5 meter gauge.

  -------------------------------------- ------------ ---------- ---------
                                         *Concrete*   *Hybrid*   *Steel*

  Density (kg/*M3*)                      2,400                   7,860

  Elasticity (E, GPa)                    30                      207

  Top thickness (mm)                     145          15         15

  Side wall thickness (mm)               145          145        13

  Bottom wall thickness (mm)             145          45         19

  Mass (kg/m)                            1,767        1,804      751

  EI (N-m^2^)                            5280         7140       5480

  Area (m^2^)                            0.6149       0.6345     0.0765

  I (m^4^)                               0.1755       0.2421     0.0293

  Static deflection (mm)                 8.84         6.3        8.51

  Thermal gradient deflection (mm)       3            7          9

  Creep deflection (mm)                  2            2          0

  f~1~ (anti-symmetrical, Hz)            2.09         2.43       3.44

  f~2~ (symmetrical, Hz)                 3.27         3.80       5.38
  -------------------------------------- ------------ ---------- ---------

All beams are for a double-span beam 72 m (236') long and 1.6 m (58")
high and 1.5 m (59") gauge. For a single span beam the static deflection
is 30% higher.

### Live load deflections

Deflection and ride-quality considerations, rather than strength,
governed the design of both the steel and concrete alternates. Both are
operating well below their safe load-carrying capacity. The quantity EI
(elasticity times moment of inertia) for the steel alternate is 5500
MN·m^2^, while that for the concrete alternate is 5300 MN·m^2^. The live
load deflections for the two are 10 mm and 9 mm respectively. The live
load deflection of the concrete alternate is slightly lower, even though
it has smaller section stiffness, because of the monolithic connection
at the interior pier. Preliminary estimates for the dynamic
amplification of the vehicle loading were 20%. A value of 20% has been
used in these deflection calculations, and that value will be updated as
the design of the system progresses. Structural damping for either
alternate will be very small, on the order of 1% or 2%, and will do
little to reduce the immediate dynamic effects of vehicle loading,
though it will have an important effect on the time the guideway
continues to vibrate after the vehicle has passed.

The hybrid section is envisaged as the concrete section with a steel
plate attached at the top with sufficient shear-flow capacity to make
the plate act compositely with the concrete. The plate would be made
thick enough to support the vertical load from the vehicle and windings
in transverse bending to transfer it to the girder. It would not be
considered for the strength design for longitudinal bending. The
increase in stiffness would only be considered for the reduction in
deflection that it would provide. The section stiffness EI for the
hybrid section is about 7140 MN·m^2^, which would reduce the live load
deflection to about 7 mm.

The live load performance of the steel and concrete alternates are very
similar. The steel alternate exhibits a lower dynamic response because
it has a lower mass for the same stiffness, which results in a
fundamental period that is significantly shorter than the transit time
of the vehicle. The monolithic connection that is possible for the
concrete alternate helps to increase its stiffness and compensate for
the fact that it's fundamental period is closer to the transit time and
therefore increases its dynamic response. That is, even though its
dynamic deflection is greater, its static deflection is less, such that
the total deflection is about the same. It is important to note that it
is the vertical acceleration of the vehicle that is important, and not
the dynamic deflection of the guideway. The total live load deflection,
static plus dynamic, is a good proxy for vehicle acceleration, since the
vehicle has to travel vertically from zero to the full deflection and
back in the time it takes to cross the span. Since the total live load
deflections are very similar, the ride quality will be similar as well.
The hybrid alternate will have the best live load performance because it
has the smallest total live load deflection.

The live load deflections in curved spans will be greater than those in
tangent spans because of the additional component from twisting.
Moreover, the twist itself will be undesirable if it becomes too great.
Deflections were computed for a 20 m span on an 18.3 m radius to
determine the possible extent of this problem. A vertical deflection of
about 6 mm was found, which is less than that for the typical tangent
span, owing to the reduced span length. The maximum twist results in a
difference in elevation between the inner and outer suspension rail of
about 8 mm, which is within acceptable limits. For comparison, the
difference in elevation from a 6° superelevation will be 157 mm.

### Thermal deflections

The deflection under live load is not the only consideration for ride
quality. Thermal gradients will also contribute to the total deflection.
At this stage only vertical thermal gradients have been studied. The
effects of horizontal thermal gradients will be considered at a later
stage of the study. The thermal gradient for the steel cross section was
taken from the Federal Railroad Administration Report No.
DOT/FRA/ORD-94/10, Safety of High-speed Magnetic Levitation
Transportation Systems. The thermal gradient for the concrete alternate
was taken from the American Association of State Highway and
Transportation Officials (AASHTO) Load and Resistance Factor Design
(LRFD) Bridge Design Specifications, 2002.

Analyses of the sections for thermal gradients show that the steel
alternate exhibits significantly higher deflections under this effect,
with an upward deflection of about 9 mm. The upward thermal gradient
deflection for the concrete alternate is about 3 mm. The peak
temperature for the thermal gradient for the steel structure is higher
than that for the concrete, as would be expected. However it is only
slightly higher and the differences in temperature alone cannot explain
the large difference in the thermal gradient deflection. The principal
cause of the difference is the difference in section geometry. Since the
temperature gradient is very steep at the top slab, the thickness of the
top slab of the concrete alternate results in an average temperature in
the slab much less than the peak temperature at the extreme fiber. In
contrast, the entire thickness of the top plate of the steel alternate
is effectively at the peak temperature, and therefore tends to cause a
much greater curvature in the steel section.

Reflective coatings and/or insulation may be used to reduce the
temperature peaks at the surface of the section to reduce deflections.
Such treatment would be effective for both concrete and steel
alternates, but would obviously be more worthwhile for the steel
alternate. Of course the addition of insulation will have cost
implications and perhaps maintenance implications as well.

The situation for the hybrid alternate is not as clear. The temperature
in the top plate of this section will probably be higher than what was
found for a hollow steel girder, since it will tend to be insulated
below by the concrete. However it is probably also safe to assume that
the average temperature in the concrete top slab will be less than it is
in the concrete alternate. In the absence of any data on the
temperatures in such a structure, we have assumed that the steel plate
will see the same temperature as the top plate of the steel alternate,
and that the temperature changes in the concrete portion of the section
will be negligible. In response to such a loading, the deflection of the
hybrid alternate is midway between those for the concrete and steel
alternates.

### Long term deflections

The effect of long-term concrete deformations must also be added to the
deflections from thermal gradients in order to get a meaningful
comparison of the deflections affecting ride quality for the three
alternates.

The long-term deflections of concrete can be separated into two
components: shrinkage and creep. Shrinkage occurs independently of the
applied loads and it does not tend to cause deflections in the
superstructure, except for the secondary effect that it has on
pre-stressing loss and the effect it has on column shortening. Creep
occurs in response to a sustained applied load and tends to increase
deflections that exist in the structure from those loads.

Both steel and concrete alternates will experience deflections due to
shrinkage shortening of the concrete column over time. The magnitude of
the deflection will depend on the ambient humidity, curing practices and
the height of the column. Strains can vary from about 200 to 500
microstrain. For "average" conditions, shrinkage strains that occur
after erection of the superstructure on the order of 200 microstrain can
be expected. For a 15 m high column (column + foundation shaft), a
deflection of about 3 mm results. Column shortening, however, will not
affect the ride quality except at abrupt changes in column height, such
as stations and abutments where the difference in deflections between
adjacent columns is large. Shrinkage will not otherwise affect the
deflections in the superstructure, except that it will contribute to the
loss of prestress in the concrete alternate, which will have some small
effect of the pre-stressing deflection.

The creep strain is proportional to the stress in the structure under
permanent loading. Permanent loading includes the girder self weight,
the superimposed loads from the windings and their supports, and
pre-stressing. Since pre-stressing will tend to cause curvatures in the
opposite direction from dead load bending, the creep deflection from
pre-stressing will counteract creep deflection from dead loads, just as
elastic deflections from pre-stressing will counteract elastic
deflections from dead load. Since the creep curvature will depend on the
total moment on the section over time, it is convenient to think about a
"creep-inducing moment" which is the difference between the
pre-stressing moment and the dead load moment. If the pre-stressing
moment is identically equal and opposite to the dead load moment along
the entire structure, the creep-inducing moment will be zero and
therefore the vertical creep deflection will be zero. A pre-stressing
design that creates moments equal and opposite to the dead load moments
is generally referred to as a "balanced" design, in other words the
pre-stressing balances the dead load.

It is generally not practical or economical to exactly balance the dead
load with pre-stressing. However, in the case of the *M3* system the
unusually light live load and girder make it possible to design
pre-stressing that is very close to balanced without an excessive
economic impact.

### Total deflections and camber

For both the steel and concrete alternates, it is possible -- and
necessary -- to camber the girders in anticipation of service
deflections. Both alternates will have to be cambered for dead load
deflections. The concrete alternate would also have to be cambered for
creep so that, with time, those deflections will tend to bring the
riding surface closer to flat and level instead of tending to increase
the deflections.

Typically for roadway, and even light rail bridges, the girders are
cambered to end up "flat" under permanent load deflections. It is also
possible, however, to consider cambering the beams for live and thermal
deflections. This is especially interesting in the case of *M3*, since
cambering to counteract live load deflections would reduce the vertical
acceleration of the vehicle as it crosses a span and improve ride
quality. Though such camber would be beneficial, it will take careful
study to determine what the actual optimum camber would be, since it
would be necessary to consider the transient nature of thermal
deflections, and the fact that the weight of the vehicle is not
constant.

The worst-case deflection for ride quality could be some combination of
all of the above-mentioned deflections -- or no net deflection at all.
For example, in the case of the steel alternate, the thermal gradient
deflection is a positive 9 mm, while the live load deflection is about
equal and opposite to that value. If the vehicle should pass at a time
when the full thermal deflection is present, the net result would be
that the total deflection due to live load and thermal gradients would
be zero, which would be beneficial to ride quality. In this scenario, it
is clear that cambering the girder upward to completely counteract live
load deflections would be counterproductive.

Note that negative thermal gradients can exist in bridge girders. Such
negative gradients for concrete bridges are presented in the National
Cooperative Highway Research Program (NCHRP) Report 276, Thermal Effects
in Concrete Bridge Structures. Though there is no similar report for all
steel box girders to the authors' knowledge, certainly such gradients
exist, and present a topic for further study.

Assuming for the moment that the deflection due to a negative thermal
gradient is equal to the opposite of half the deflection from positive
gradient, it may be that the optimum camber for the steel alternate is
some compromise value. A value of about half of the live load deflection
(plus the dead load deflection) would be appropriate as a first
estimate. This value should be adjusted based on the expected fraction
of the time that the thermal gradient deflections exist and their
correlation with the operating hours of the system and the expected
total vehicle weight during those hours.

In the case of the concrete alternate, creep and thermal deflections
would have to be considered as well when figuring live load camber. The
creep deflection should be considered from the time that the suspension
rail is installed, because the installation will account for creep
occurring before that time. In our study this so-called "service creep"
results in sag, though that would not necessarily always be the case.
Typically the girder would be cambered to arrive at a "flat" condition
late in service when creep has run its course. However since the creep
deflection could potentially be positive or negative and it has to be
considered in conjunction with the thermal deflections, it is not
immediately clear that the same approach would be appropriate for the
*M3* system, and the question needs further study. Assuming that service
creep results in a sag of 3 mm, and positive thermal gradients result in
a hogging that is roughly equal and opposite, something close to full
camber to compensate for live load deflections would be appropriate.
Table 6.2 shows deflections due to creep, temperature and live loads.

Table 6.2. Deflections due to creep, temperature and live loads.

+----------+-----------+--------------+-------------------+-----------+
|          | *Creep*   | *Peak*       | *Thermal          | *Live     |
|          |           |              | Gradient*         | Load*     |
|          | *De       | *            |                   |           |
|          | flection* | Temperature* | *Peak Deflection* | *De       |
|          |           |              |                   | flection* |
+----------+-----------+--------------+-------------------+-----------+
| Concrete | -3 mm     | 23 °C        | 3 mm              | -9 mm     |
+----------+-----------+--------------+-------------------+-----------+
| Steel    | N/A       | 30 °C        | 9 mm              | -10 mm    |
+----------+-----------+--------------+-------------------+-----------+
| Hybrid   | -2 mm     | 30 °C        | 7 mm              | -7 mm     |
+----------+-----------+--------------+-------------------+-----------+

### Horizontal deflections

The guideway will be subject to horizontal deflections during operations
from wind, live loads and thermal loads, which will also affect the ride
quality. Horizontal thermal gradients require further study, as
discussed above. Horizontal deflections from wind and live loads can be
broken down into a guideway-beam component, which comes from horizontal
bending in the beams, and a pier component, which is the result of
bending in the pier and rotations in the foundation.

In the case of wind, there will be a dynamic structure response, and it
will depend on the wind speed, gust characteristics, and the geometry
(drag coefficient and natural frequencies) of the guideway. A complete
analysis that considers all of these factors is beyond the scope of the
current work; however, as a first approximation it is possible to
calculate static deflection based on the wind loads given in the AASHTO
code. For a 100 mph wind, AASHTO gives a net total pressure of 50 psf
(2.4 kPa). Applying this load to the windward beam only, a total
deflection of 60 mm is found. Approximately 40 mm of that deflection
comes from column bending. There will also be a load on the leeward
beam, which is not considered in the above numbers. AASHTO stipulates a
value of half that for the windward chord for leeward truss chords. If
that loading is used for the leeward beam, the pier deflection will
increase by about 50% to 60 mm. This is a relatively large deflection,
and it may dictate the use of stiffer substructure elements, though
horizontal deflections at the top of the pier of up to 100 mm have been
allowed for some light rail systems.

Assuming that the vehicle will only operate at full speed in winds of 50
mph or less, the deflection used for assessing the ride quality can be
reduced. Since the wind pressure is proportional to the square of the
wind velocity, the deflections will be one quarter of those given above,
i.e. 15 mm for the piers and 5 mm for the beam.

### Ride quality considerations

The static and dynamic deflection under live load are major
considerations for ride quality, but they are not the only ones. Thermal
gradients and long-term material deformations (creep and shrinkage) will
also contribute to the total deflection. At this stage only vertical
thermal gradients have been studied. The effects of horizontal thermal
gradients will be considered at a later stage of the study. The thermal
gradient for the steel cross section was taken from the Federal Railroad
Administration Report No. DOT/FRA/ORD-94/10, "Safety of High-speed
Magnetic Levitation Transportation Systems..." and is given in the
appendix. The thermal gradient for the concrete alternate was taken from
the AASHTO LRFD Bridge Design Specifications, 2002.

In the concrete alternate, the combination of deflections that would
cause the worst ride quality is probably creep and live load deflection.
The total deflection of live load alone is greater than the combination,
since the creep deflection is positive at the point of maximum live load
deflection; however, the creep deflection causes double curvature in the
span, which would be more unfavorable from a ride-quality perspective.
The maximum change in deflection for this combination is about 6 mm and
it occurs over about half a span length. Again, efforts would be made to
camber the girder to help reduce this effect. A reduction of half of the
creep deflection can be reasonably expected.

For both the steel and concrete alternates, it is possible to camber the
girders in anticipation of shrinkage and creep deflections. That way,
with time, those deflections will tend to bring the riding surface
closer to flat and level instead of tending to increase the deflections.
Precamber can also be used to compensate for normal live load, but
variations in load and dynamic behavior cannot be compensated.

The seismic design requirements for the guideway for the *M3* system are
not fundamentally different from those for other bridge structures.
Ideally the foundation and superstructure will be designed to remain
elastic, and the columns detailed to respond in a ductile manner, though
that approach may change depending on the location of the site and the
local seismic risks. Further requirements unique to the *M3* system
could include maximum tolerable deflection limits during seismic
response (for example angle deviations at expansion joints) or buffers
to prevent the vehicle from locking up and stopping too suddenly if it
bumps up against the guideway. Such additional safety considerations
will have to be addressed as the mechanical systems for the vehicle and
suspension rail are developed further.

Ride quality is often measured by plotting a spectrum of vertical
acceleration vs. frequency (for a vehicle moving along the guideways)
and comparing that with an empirically derived limit, such as the
International Standards Organization ride quality standard shown in Fig.
5.2.

![](media/image15.wmf){width="5.992361111111111in"
height="1.957638888888889in"}

[]{#__RefHeading___Toc89856178 .anchor}Fig. 5.2. ISO Standard for
acceptable vertical acceleration for good ride quality.

The problem of achieving good ride quality is particularly difficult at
high speed because the vertical acceleration tends to increase as the
square of the speed. Figure 5.3 shows the computed vertical acceleration
spectrum for the baseline vehicle traveling along the concrete guideway
at 45 m/s. This simulation assumes full live load deflection with no
precamber and no deflection reduction due to the attachment of the beam
to the middle pier, but it neglects deflection due to creep and thermal
effects. The blue (left) spectrum is for the front of the vehicle and
the red is for the rear.

The vertical spectrum is dominated by the pier-crossing frequency, 1.25
Hz, and the lowest resonant frequency of the beam, 2.4 Hz, modulated by
the beam crossing frequency. There is also some response near the higher
frequency beam resonances: 3.8 and 9.8 Hz. Particularly noteworthy is
the low amplitude of high frequency components, a result of the
distributed nature of the magnetic suspension. More detailed and
accurate simulations will be done in later phases of *M3* development,
but it appears that the *M3* vehicle can have dramatically better ride
quality than the ISO limits given in Fig. 5.2.

![](media/image16.wmf){width="5.997916666666667in"
height="2.1152777777777776in"}

[]{#__RefHeading___Toc89856179 .anchor}Fig. 5.3. Vertical acceleration
spectrum at 45 m/s on concrete guideway.

### Longitudinal design

Because the guideway design is controlled by deflections, the stresses
from service loads are very minor. In the steel alternate the total
service stress is less than 20% of yield, and the live load stresses are
almost insignificant. The situation is much the same for the concrete
alternate, though the stresses are somewhat higher in relation to
allowable limits, at least for shear. In the case of a guideway on an 18
m horizontal curve, the shear stresses from shear and torsion are still
well within acceptable limits. For example, in the case of the concrete
alternate the principal tensile stress in the web during service loading
is less than one MPa (a value of about 1.5 would be acceptable). The
shear stress in the steel alternate is even less compared with the
allowable value.

### Seismic design

A seismic analysis of the system following the AASHTO LRFD
specifications was performed on the two alternates to verify the
preliminary member sizes. A peak rock acceleration of 0.4 *g* and a soil
coefficient of 1.0 were assumed, indicating a high seismic zone on firm
soil or rock. The foundation was assumed to be a 1.8-meter-diameter
single drilled shaft. This foundation type has been gaining popularity
in California because of its excellent seismic performance and
simplicity of construction. Because continuous girders are restrained
longitudinally at the center column and left free to expand at the outer
columns, a single column resists the longitudinal seismic actions.
During transverse seismic response, the girders span horizontally
between columns so that all columns are acting. Therefore the
longitudinal response controls the design of the column. At some point
it may be worthwhile to consider pinning the superstructure at one outer
column in high seismic zones to allow all of the columns to participate
in the longitudinal seismic response, however it is beyond the scope of
this report to develop the special details required for such a
connection.

A 1.0-meter diameter column was chosen for the steel alternate. This
alternates lightweight results in lower seismic demands and allows for
the use of a smaller foundation and substructure elements. The results
of the preliminary seismic analyses indicate that this column and
foundation are adequate for the loads suggested by the AASHTO
specification.

The key point to consider for the steel alternate superstructure with
regards to seismic performance is that it will be supported on bearings.
The tall narrow cross section will have to be stabilized either by
providing tie-down bearings, diaphragms between the girders at the
piers, or by devising a continuous connection between the girders and
the hammerhead. Adequate bearing-seat width and restrainers will be
provided to prevent loss-of-support failures.

A 1.2-meter diameter column was used for the concrete alternate. With
the greater mass of this alternate, the larger stiffness keeps the
displacement at acceptable levels. The same diameter drilled shaft is
used, though it will require a greater steel content and penetration
into the founding rock or soil.

Stability is provided by the monolithic connection at the interior pier.
As with the steel alternate, shear keys, adequate seat width and
restrainer cables will be required to maintain support at the expansion
piers.

### Conclusions and recommendations

All of the three alternates developed in this preliminary study would be
acceptable for the guideway for the *M3* system. An effort was made to
achieve approximately equal performance between the three alternates so
that the cost comparisons would be meaningful. The authors believe that
this has been achieved more or less, though the different
characteristics of concrete and steel have made exact equality
impossible. The one that could possibly be called an outlier is the
hybrid alternate, which has significantly greater stiffness and
therefore lower live load deflections. It was necessary to develop it in
this way, however, due to the nature of the construction technique
envisaged.

It is difficult to decide which alternate would be preferred and
probably impossible without knowing the site, length of the project, and
local construction conditions. In general it is reasonable to conclude
that the concrete alternate will be the least expensive by a significant
margin. It is also likely that it will require the least maintenance and
have the lowest lifecycle cost. This will be borne out in most locations
in the United States, though there may be some places where steel may be
less expensive because of local contractor experience and availability
of the materials.

It is difficult to say which alternate will perform the best in terms of
ride-quality. The live load deflection response is similar for steel and
concrete, with the concrete having a slightly greater dynamic response
but a smaller static response. The total deflection of the hybrid is the
lowest, giving it the best live load behavior. The price premium of the
hybrid alternate over the concrete alternate is essentially paying for
improved ride quality.

The thermal deflection of the steel alternate causes its greatest
performance problem. Though the vertical gradient causes a significant
deflection, the deflections from horizontal gradients are likely to be a
worse problem and need further study. We believe that insulation and
reflective coatings will solve this problem, but at some as yet unknown
increased cost.

Creep deflections are the greatest concern for the concrete alternate,
and although they could theoretically be limited to acceptable levels,
uncertainties about correctly predicting them add a greater risk to this
alternate. The hybrid alternate faces the same construction risk from
creep, and the additional uncertainty about our ability to attach the
top plate with sufficient stiffness and strength. It is expected that it
will be possible to construct all of the alternates within adequate
dimensional tolerances. Although past experience has shown that the
tolerances actually achieved for both steel and concrete may be at the
limit of what is needed, it should also be recognized that the current
technology has been developed to deliver only the tolerances that have
been required by road and rail bridges, and it should be expected that
improvements for both materials can be realized if required for the *M3*
system.

Based on our findings to date, there are potentially considerable
advantages to the concrete alternate for its lower cost and its
thermal-deflection characteristics. Its principal detractions are the
uncertainties involved with creep deflections and the attendant
construction risk. The advantages are significant enough though that it
is advisable to construct a test segment to quantify and understand the
risks. We recommend therefore that a prototype system of limited scale
be built using concrete. Depending on the scale and end use of the
system, it may be appropriate to build all of it, or only a portion of
it in concrete, and the rest in steel. A cast-in-place structure would
probably be the best choice, as it would be the most appropriate for a
guideway of limited length and would still allow us to study the
dimensional stability of concrete.

Several other important issues remain to be studied at this stage.
Horizontal deflections from thermal gradients will likely cause
deflections equal to or even larger than the deflections from vertical
gradients. Since horizontal accelerations are more disturbing to
passengers than vertical accelerations, this is an important area to
study. Work needs to be done to determine the horizontal gradients that
will exist in concrete and steel structures, and change the cross
sections if necessary, to limit the deflections set up by these
gradients. We recommend that both the steel and the concrete alternates
be advanced through this next stage.

Likewise, it will be important to consider horizontal accelerations from
wind and live loads. The effect on those accelerations from deformations
in the substructure should be considered in evaluating these effects.
Work to be done includes determining the aerodynamic properties of the
cross section, the response of the structure to a generic wind climate,
and the effect of wind oscillations on vehicle performance. For live
loads, additional rolling-stock type analyses should be performed for
various guideway parameters to determine acceptable limits for
foundation stiffness, pier height, etc. Work to optimize the span
lengths for curves of various radii would also be warranted.

The mounting hardware for the suspension rails is probably the most
important item to develop. It needs to allow for easy adjustment both
horizontally and vertically. If it were possible to develop hardware
that allows for rapid and economical readjustment, then it would be
possible to assume more risk in the dimensional stability of the initial
construction, and would help greatly in developing the lowest cost
guideway.

## Ride quality analysis of baseline design

The concrete box beam guideway has been determined to be the lowest cost
method of building a guideway that allows good ride quality for our
baseline vehicle operating at speeds up to 45 m/s (101 mph). The focus
of this Section is to discuss ride quality for vehicles moving on
concrete guideway beams.

### Concrete beam properties

Vehicle considerations have caused us to increase the gauge of the
suspension rail from that of the original design. The new gauge is set
at 1.7 m suggesting a somewhat wider beam. The ride-quality studies
presented herein consider a beam with dimensions shown in Fig. 5.4. The
width may change as details of the suspension-rail mounting hardware are
finalized. The span has been kept at 36 m. Since the target of this
analysis is a test track, the structure has been simplified to a
two-span continuous single-track guideway with simple supports. No
column is considered in the analyses since the test track will be
supported on zero-height piers. Other beam data are included in Table
5.3. Note that a mass of 150 kg per meter has been added to account for
the suspension rail and mounting hardware.

Table 5.3. Concrete beam parameters.

  ------------------------------------ ----------------------- -----------
  Concrete elastic modulus             30,000                  MPa

  Beam inertia                         0.2067                  m^4^

  Beam area                            0.673                   m^2^

  Concrete specific weight             23.56                   kN/m^3^

  Total beam weight                    17.3                    kN/m

  Beam natural frequencies             2.27, 3.55, 9.08        Hz
  ------------------------------------ ----------------------- -----------

![](media/image17.wmf){width="2.4375in" height="3.25in"}

[]{#__RefHeading___Toc89856180 .anchor}Fig. 5.4. New guideway beam for
increased gauge.

### Rigid vehicle analysis validation

Data for the *M3* vehicle at the target cruising speed are as follows:

Vehicle velocity..................\...45 m/s

Vehicle mass.........................7 Mg

Vehicle length.......................10 meters

Pier-crossing frequency ..........1.25 "Hz" (45 m/s ÷ 36 m)

Beam natural frequencies..........2.27, 3.55, 9.08 Hz

These parameters are used throughout as the baseline case for
ride-quality studies, as in the previous work.

Our previous analyses of ride quality have been done in the time domain,
with the load of the vehicle traversing the beams represented by nodal
loads along the beam. These nodal loads were assigned to time functions,
which ramped them up when the vehicle approached a node and back down
after it passed. The movement of the vehicle was thereby modeled as a
wave of nodal loads along the span.

While this methodology worked very well for capturing the dynamic
behavior of the beam, as would be needed for a stress analysis of the
beam, it was not sufficient to directly describe the quantities needed
for a ride-quality assessment. This is because the vertical acceleration
of the car body, which is the quantity of interest for studying ride
quality, is made up of several components. Among these are:

-   The vertical acceleration of the supporting beam.

-   The vertical movement of the vehicle as it follows the curve of the
    beam (deflection plus fabrication curve).

-   The movement of the car body relative to the beam, i.e. compression
    and extension of the suspension.

-   The vibration of the car body itself.

The results of ride quality analysis are shown in Figures 5.5-6.

![](media/image18.wmf){width="5.991666666666666in"
height="2.4368055555555554in"}

[]{#__RefHeading___Toc89856181 .anchor}Fig. 5.5. Vertical acceleration
of a rigid vehicle at 45 m/s.

The red curve is for the back of the vehicle and the blue for the front.

The corresponding acceleration spectrum is shown in Figure 5.10.

![](media/image19.wmf){width="6.002083333333333in"
height="1.9069444444444446in"}

[]{#__RefHeading___Toc89856182 .anchor}Fig. 5.6. Vertical acceleration
spectrum for rigid vehicle at 45 m/s.

### M3 vehicle suspension

The function of the suspension is to isolate the car body from the
irregularities of the guideway. Ride comfort is a function of high
frequency vibrations, vertical spring actions or "bounce", and body
pitch and roll that the car body experiences in crossing irregularities
in the guideway. High frequency vibrations relate to the vibration of
the car body itself, which is beyond the scope of this study. Body roll
involves 3D behavior of the vehicle through horizontal turns, which is
not part of this study either. It is the vertical "bounce" and the pitch
of the vehicle as they vary with time that will be considered here.

Vertical accelerations can produce rider discomfort in different ways,
depending on their frequency content. Low frequency vibrations, in the
range of 0.5 to 0.8 Hz are usually associated with motion sickness.
Moderate frequency vibrations in the range of 5 to 6 Hz affect the
visceral regions. Higher frequency vibrations of up to 20 Hz are bad for
the head and neck. Most vehicle suspensions target a natural frequency
of 1 to 2 Hz because that is roughly the frequency of walking, and is
believed to be the frequency at which the ride will be most comfortable,
though designers have started to question this approach.

In the current design of the *M3* system, the baseline vehicle velocity
is 45 m/s and the beam span is 36 m, resulting in a pier-crossing
frequency of 1.25 Hz. Since this essentially represents the frequency of
a forcing function, it would be expected that much of the car body
acceleration would occur at this frequency.

The fundamental natural frequency of the current beam design is 2.27 Hz.
This corresponds to a two-span beam with three simple supports. (As
indicated previously, a monolithic connection to the column is not
considered, which is a departure from the previous study.)

The natural frequency of the vehicle would ideally be within the 1 to
2-Hz frequency range as well, but different from the pier-crossing
frequency and the natural frequency of the guideway beam. The vehicle
has therefore been sprung such that the frequencies of the first two
modes are roughly 1.4 and 1.8 Hz. The rear spring has been made nearly
twice as stiff as the front so that the vehicle is not symmetrical front
to back. This avoids having pure bounce and pitching modes. Instead the
first mode is a "Front-End-Bounce" (FEB) mode, with little movement in
the rear suspension. The second conversely is a "Rear-End-Bounce" (REB)
mode. Figures 5.7-8 show the key ideas.

![](media/image20.jpeg){width="5.998611111111111in"
height="2.0819444444444444in"}

[]{#__RefHeading___Toc89856183 .anchor}Fig. 5.7. Vehicle
front-end-bounce mode -- f = 1.41 Hz.

![](media/image21.jpeg){width="5.992361111111111in"
height="2.5194444444444444in"}

[]{#__RefHeading___Toc89856184 .anchor}Fig. 5.8. Vehicle rear-end-bounce
mode -- f = 1.87 Hz.

The vehicle characteristics are preliminary at this stage. No car body
flexibility is considered, the mass distribution is assumed to be
uniform, and the un-sprung weight is assumed to be 20% of the total
weight. A relatively high un-sprung weight is used because it was
assumed that the mass of the magnets in the pods will be significant and
an advanced lightweight car body will be used. The spring stiffness has
been chosen to give natural frequencies comparable to those of
automobiles and other transit vehicles. With the beam-crossing frequency
and the vehicle natural frequencies and damping that we have,
calculation of a simple single degree-of-freedom transmissibility based
on the frequency ratio of the pier-crossing frequency and the vehicle
natural frequency suggests that the deflections resulting from the
vehicle following the sag of the beam will be amplified. This is
corroborated by the numerical results, which show car body deflections
greater than the pod deflections.

### Ride quality criterion

The ride-quality standard of the International Standards Organization
limits rms acceleration as a function of frequency, as illustrated in
Figure 5.2. Acceleration spectra from the analysis results for zero to
15 mm camber have been compared with this standard. For cambers of 0 and
5 mm, the car body accelerations are below the limits set out in the ISO
standard for two hours of exposure, indicating an excellent ride. When
the camber is increased to 10 mm, the acceleration exceeds the two-hour
standard at a frequency of 2.5 Hz, but is still below the
one-hour-exposure standard. At 15 mm of camber, the one-hour standard is
exceeded, again in the frequency range of 2.5 Hz. Above 15 mm of camber
the ride is above the ISO limit, and not acceptable for long trips.

### Increase in beam stiffness

It is tempting to increase the stiffness of the beam in an effort to
improve the ride quality, since the vehicle accelerations are directly
related to the beam deflections. However to do so may not necessarily be
the best approach. Our current beam design delivers excellent ride
quality for cambers in the range of zero to 5 mm at a maximum velocity
of 45 m/s. It is the increase in camber that is causing the ride to
deteriorate, not the flexibility of the beam. Since the uncontrollable
camber from creep and thermal loading is not a function of beam
stiffness, increasing the stiffness may not be a good way to increase
the ride quality.

In the case of thermal gradients, the deflection will be relatively
insensitive to increases in beam inertia, within small excursions from
the current beam dimensions. Thermal deflections are more likely to be
controlled effectively by providing an upward facing surface in the form
of a protruding flange near the bottom slab to absorb radiation and
increase the temperature at the bottom of the section, counteracting the
expansion of the top slab, or to provide insulation or a reflective
coating on the top slab. If the beam is made stiffer without reducing
the hogging from thermal loading, the ride may actually become worse.
That is because a flexible beam deflects to compensate somewhat for
misalignments. This can be seen below in the results of analyses done on
very stiff beams with non-zero camber. The accelerations increase with
beam stiffness. This is an important topic for further study.

### Higher speeds

The *M3* vehicle will be capable of speeds higher than 45 m/s, in the
case where a particular urban alignment allows higher speeds. We have
studied the vehicle response and Figs. 5.9-10 show the acceleration
history and spectrum from this analysis for 60 m/s (134 mph) to see how
the ride quality degenerates with speed.

![](media/image22.wmf){width="5.991666666666666in"
height="2.4368055555555554in"}

[]{#__RefHeading___Toc89856185 .anchor}Fig. 5.9. Acceleration history
for sprung vehicle at 60 m/s (134 mph).

![](media/image23.wmf){width="6.002083333333333in"
height="1.9069444444444446in"}

[]{#__RefHeading___Toc89856186 .anchor}Fig. 5.10. Acceleration spectrum
for sprung vehicle at 60 m/s (134 mph).

The rms acceleration at the beam-crossing frequency (now 1.67 Hz) has
increased to 5.5% *g* at the rear of the vehicle. This is very near the
one-hour limit of the ISO standard. For long distances, a stiffer beam
and tighter suspension rail tolerances would likely be required. This
could be achieved, for example, by shortening the span with the current
cross section. It is unlikely, however, that trip length will exceed on
hour for an urban system, and even less likely that long stretches of
45+ m/s could be achieved. It is therefore anticipated that higher
speeds are possible with the current system, if careful attention is
paid to the ride-quality requirements.

### Ride quality conclusions for baseline beam

The conclusion to be drawn from this study is that the current beam
design provides excellent ride quality for the vehicle speed considered,
and increases in speed may be possible for short runs. It is also clear
that controlling camber is as important as beam stiffness for insuring
ride quality. Construction tolerances, thermal deflections, and
long-term deflections are all important parameters that must be dealt
with in order to achieve the ride quality desired. Improvements in the
vehicle design, especially the possibility of the addition of an active
suspension, will also lead to better ride quality.

## Concrete beam creep considerations

As discussed in reference in the Ride Quality discussion above, camber
is a very important aspect of ride quality. In the case of concrete
beams, adverse camber due to creep could pose a problem, if it is not
adequately accounted for in design. This task was intended to review the
experience with the deflection of actual pre-stressed beams in service.
Unfortunately, very little useful data have been found by the authors to
date. The studies that they are aware of tend to be for bridge types
that are too different in configuration and scale to be applicable to
the *M3* guideway.

Nevertheless, some general information regarding the errors in
deflection prediction in concrete bridges has been found. Stevula
assessed the ramifications of several types of modeling inaccuracies on
the predicted deflection of a large post-tensioned box-girder bridge. He
found that neglecting shear deflections and shear lag in the
computations was one of the most significant sources of inaccuracy.
Neglect of cracking, both shear and flexural, was also cited as an
important source of error. Finally, he advised careful assessment of the
contribution of thermal gradients to long-term deflections. Thermal
gradients contribute to long-term deflections by causing cyclical
tensile strains that gradually reduce the tensile strength of concrete
until flexural cracks are initiated, which then lead to greater
deflection.

Favre et al. have shown that live load deflections will gradually
increase with time because of degradation of the steel-concrete
interface at flexural cracks. The magnitude of this degradation is a
function of the amount by which these cracks move during loading, which
depends on the level of pre-stressing. They report that higher levels of
pre-stressing moderate this effect by keeping the cracks in compression
and preventing a fatigue-like response.

Errors in the prediction of creep properties of the concrete were not
cited.

We will now look at the impact of each of these issues in turn for the
case of the *M3* system.

*Shear Deflections* are easily accounted for with modern bridge-design
software, and their importance can easily be assessed for the *M3*
system. With our current configuration they do not pose a significant
problem.

*Shear Lag* is most important for box-girder structures with geometries
appropriate for roadway bridges. The wide top slabs and long
cantilever-slab overhangs present a longer load path between flexural
normal stresses and the shear stresses at supports that generate them.
Pre-stressing exacerbates this effect, as pre-stressing forces usually
generate very little shear at a support and thus are usually well
distributed over the section at a pier. Generally this would suggest the
use of different cross-section properties for vertical loads and
pre-stressing, which is seldom done in practice. In the case of the *M3*
system, the width of the box is kept small by the gauge of the vehicle,
and there are no long overhanging slabs, so the section will not be as
sensitive to shear lag as a typical roadway-bridge cross section.
Nevertheless, a careful assessment of the shear-lag effects will be made
during the final design stage of an actual system.

*Thermal Gradients* are a cause for concern in and of themselves for the
deflections they cause. The direct deflections and stresses from them
have already been considered in the first phase of this project. Based
on the temperature information we have, and the stresses we have
calculated, there is little danger of tensile cracking from thermal
gradients. The greatest concern would be that we have underestimated the
temperatures in the structure from solar radiation. Our intent is to
look at the applicability and efficacy of coatings and insulation as
time and resources permit, as a possible way to eliminate this issue.

# Vehicle

The MagneMotion Team has not yet developed a detailed vehicle design but
the important parameters have been determined. This section discusses a
baseline vehicle design that is similar to the vehicle depicted on the
cover and in Fig. 2.1.

## Size

European and Japanese maglev developers have always viewed maglev as a
modern form of train travel with the potential for higher speeds, lower
maintenance cost, etc. The German Transrapid and the Japanese and
European high-speed designs all use multi-car trains with each train
carrying several hundred passengers and train spacing of several
minutes. In contrast, U.S. maglev developers have always thought of
maglev as a form of bus or airplane with a preference for smaller
vehicles operating more frequently. All 4 designs that resulted from the
U.S. 1992 National Maglev Initiative recommended the use of individual
vehicles with capacities less than a 100 passengers. Following are some
of the advantages of each approach.

Larger vehicles or trains of vehicles operating with longer headway are
most beneficial for high-speed intercity operation. Advantages include:

-   Lower labor cost when operated manually;

-   Higher capacity is possible;

-   Lower aerodynamic drag per passenger;

-   Vehicles can be less expensive per passenger.

Smaller vehicles operating with shorter headway are most beneficial for
urban transit operation. Advantages include:

-   Reduced cost for elevated guideways;

-   Reduced waiting time for passengers;

-   Reduced propulsion power per vehicle;

-   Clusters of vehicles with spacing controlled electronically are more
    versatile than physically connected trains of vehicles;

-   The number of stops can be reduced by using station skipping
    strategies;

-   It is easier to reuse regenerated braking energy.

For *M3* there are major advantages of using small vehicles with short
headway so that is the basis of the baseline design. The suspension and
propulsion technology used for *M3* systems will work very well for
larger vehicles or trains but the capital and operating cost will be
greater. Our baseline vehicle can be configured in several ways: 40
passengers (12 seated), 36 passengers (24 seated), or 32 passengers (all
seated). The key dimensions are given in Table 6.1.

## Headway and capacity considerations

It is desirable to be able to operate with short headway so that high
capacity can be realized with small vehicles. This is possible because
accurate position sensing is inherent with LSM propulsion and braking
does not depend on friction. The use of short headway allows a cluster
of vehicles to act like a cluster of buses on a highway and thereby
achieve high capacity. The vehicles can operate safely with only a few
seconds headway just as cars operate on a highway with short headway,
but there does need to be space between clusters in order to allow
either in-line or off-line loading and unloading. Section 7 on Control
discusses these issues in more detail but the effect of using clusters
of vehicles with short headway capability means high capacity can be
achieved with bus-size vehicles.

## Weight

Vehicle weight is very important and there is an important tradeoff
between using a more expensive but lighter vehicle and requiring heavier
guideways and a more powerful linear motor. Steel-wheel suspended
vehicles typically have an empty vehicle weight that is 3 to 6 times the
maximum passenger weight. With careful design an LSM propelled vehicle
constructed with composite materials can lead to empty vehicle weight
less than 2 times the maximum total passenger weight. Since transit
systems spend much of their energy budget on acceleration, weight
savings have an important impact on capital and operating cost. It is
easily justifiable to pay more for a lighter vehicle. Table 6.1 gives
our best estimates of baseline vehicle overall dimensions and weight.

Table 6.1. Dimensions and weight of baseline vehicle.

  --------------------------- ------------- ------- --------------- -------
                              *Metric*              *English*       

  Length                      10            m       32.8            ft

  Width                       2.9           m       9.5             ft

  Height                      3.2           m       10.5            ft

  Rail gauge                  1.7           m       5.6             ft

  Weight empty                5,500         kg      12,100          lb

  Max. load                   3,000         kg      6,600           lb
  --------------------------- ------------- ------- --------------- -------

## Secondary suspension

The primary suspension is provided by the magnets but there will be a
secondary suspension that has two components.

1)  The magnet pods have pivots with dampers so as to allow tight
    turning radii in both horizontal and vertical directions. These
    components are needed at all speeds.

2)  Pneumatic or magnetic springs allow improved ride quality and can,
    if desired, provide active control of ride quality, including
    tilting. These components are only needed at speeds above about 20
    m/s (45 mph).

## Onboard power system

It is necessary to provide onboard power for Heating, Ventilating and
Air Conditioning (HVAC) and this power requirement is much greater than
the total of all other onboard power requirements. The total average
requirements are estimated to be 8 kW for HVAC and 4 kW for everything
else with significantly more than this for peak power. A major reason
for the low total requirement is the use of a permanent magnet
suspension that requires an order of magnitude less power per Mg of
vehicle weight than with an electromagnetic suspension. This power will
be provided by batteries plus a charging source.

For the purpose of the demonstration prototype conventional lead acid
batteries were used to power the suspension controllers but the final
design will use newer battery technology to save weight. The onboard
batteries will be charged via Inductive Power Transfer (IPT) between a
power source on the guideway and pickup coils on the vehicle.
MagneMotion has constructed such systems in the past and is confidant
that the required power can be transferred at all speeds at reasonable
cost and efficiency.

Unlike Transrapid, which depends on a 1,000 VDC sliding-contact power
pickup system at speeds below 80 km/h (50 mph), *M3* vehicles will never
require contact with the guideway and this will be a major asset in
improving reliability and decreasing cost.

## Use of larger vehicles or trains

The *M3* suspension and propulsion system can be used with almost any
size vehicle or train of vehicles. It could conceivably be used to
replace suspension and propulsion systems in competing maglev designs
with potentially lower total overall cost. However, the *M3* system
design is based on optimizing system cost and MagneMotion does not
believe the use of larger vehicles or trains has advantages except when
higher capacity than 12,000 pphpd or higher speed than 60 m/s (134 mph)
is required.

# Control System

## Introduction

For any modern mass transit system a digital control system is required.
There are many ways to implement such a control system, and one concept
is presented in this chapter. Only the high level concepts are described
here -- there are many details of implementation that are left out for
the sake of a concise, readable document.

## Objectives

Any control system for people movers should be designed with the
following goals:

*Safety*

The most important goal of the control system must be safety. According
to USDOT 2001 highway fatality statistics, more than 40,000 people died
last year in automobile crashes, a fatality rate of 1.52 people per 100
million vehicle miles traveled. While the general public accepts this
rate, they rightly hold mass transit to a much higher standard, with
outrage expressed at any deaths on a public transportation system so
safety must be the primary goal of the control system.

*Reliability*

The transit system should be reliable, such that avoidable traveler
delays are minimized, and should be efficient, so that the transport
resource is used to near its full potential and not significantly
limited by the control system. This ensures maximum return on
investment.

*Ability to achieve high capacity*

The choice of control system can have a major impact on system capacity.
The objective is to achieve the highest possible capacity consistent
with the available resources and the requirement for very safe
operation.

*Flexibility and expandability*

The control system should also be flexible, to be easily used for
transit systems of differing types (e.g. shuttle vs. network) and
variations in demand. At the same time, it should be expandable so that
the system can be upgraded with additional guideway with minimal impact
on existing routes.

*Effective fault handling*

The system should have carefully planned fault handling to deal with
problems as they occur, both expected and unexpected types of problems.

## Architecture

The architecture for the *M3* control system is hierarchical and
designed for expandability. As the system grows, more modules are added
at each of the lower levels. The hierarchical system also minimizes
communication and required processing power, as each function can be
implemented at the appropriate level. Figure 7.1 illustrates a 3-level
hierarchical system suitable for a complex system, but for a simple
system 2 levels may suffice.

![](media/image24.wmf){width="5.992361111111111in"
height="4.372222222222222in"}

[]{#__RefHeading___Toc89856187 .anchor}Fig. 7.1. Hierarchical control
system.

Following are the functions of the different levels:

*Block Controller:*

-   Constantly tracks position of one vehicle.

-   Controls vehicle according to orders from zone controllers.

-   Drives the linear motor via power electronics.

-   Keeps track of vehicle state information, vehicle ID, position,
    velocity, etc.

-   Communicates with adjacent block controllers and zone controllers.

-   Provides motor synchronization, vehicle handoff, liftoff, E-stop,
    etc.

-   Monitors status of block and inverter.

*Zone Controller*:

-   Constantly tracks positions of vehicles.

-   Monitors status of power system, block and switch controllers.

-   Provides vehicle coordination: grants movement permissions to
    vehicles via block controllers; ensures adequate vehicle spacing;
    implements safe merge strategies; responsible for vehicle protection
    functions.

-   Reports errors to central controller.

-   Interfaces to station controllers.

-   Tracks vehicle information, routing, etc.

*Central Controller:*

-   Performs global optimizations; manages vehicles; performs vehicle
    routing and switching decisions.

-   Displays system condition to operator.

-   Records and reports fault conditions.

-   Tracks network statistics.

-   Communicates with all controllers and uploads software updates to
    them.

-   Diagnoses system problems.

## Proposed control scheme

The following control scheme is based upon a control scheme implemented
by MagneMotion for a material handling system but with additional
features to insure safety and fault tolerance.

### Constraints

The control system design is strongly influenced by the system
constraints. The limitation of one vehicle per LSM block imposes a
significant constraint on how the system is operated. The system must
ensure that under any normal set of operational circumstances each
vehicle must be in a separate block. The stopping distance for a vehicle
may be several blocks so each vehicle must also at all times have a
dedicated block for the vehicle to stop, a place where no other vehicles
are allowed.

Other constraints include the headway criteria, emergency egress points,
stop exclusion areas (in switches, etc.), and emergency stop
capabilities. A variety of headway constraints may be imposed on the
system, including both 'brick-wall' and "safe-follower" types. A
brick-wall headway is defined as the minimum headway between vehicles
such that if a vehicle comes to an immediate stop (e.g. hits a brick
wall), the following vehicle will be able to stop in the intervening
distance. A safe-follower headway is defined as the minimum headway
between vehicles such that if a vehicle applies maximum braking, the
following vehicle will be able to stop without collision.

Finally, there are the ride quality and performance constraints of the
system, described as jerk, acceleration and velocity limits.

### System Characteristics

The propulsion system does not depend on friction to deliver thrust to
the vehicle and provides consistent performance in any weather
conditions. It has higher acceleration and deceleration capabilities
than steel wheel on steel rail in even the best weather conditions. The
*M3* system utilizes an inductive position-sensing system which is
capable of constantly monitoring the precise position of all vehicles at
all times. The propulsion control system is located on the wayside, so
position information is easily shared for all vehicles over a
hard-wired, low-latency communication system without the vagaries and
susceptibilities of radio communication. Knowledge of precise position
of all vehicles and the ability to apply consistent thrust in all
weather conditions greatly facilitates the implementation of a
short-headway control system.

### Control system description

The control system developed for *M3* was tailored to meet the
constraints of a long-stator LSM drive, specifically that only a single
vehicle is allowed over any motor block at one time. The control system
is based on the concept of a "target', or planned stopping point. This
concept has been proven in a commercially operating material handling
system.

In order to maximize throughput capability vehicles are operated in
clusters. Each station is sized to handle a full cluster of vehicles. By
starting and stopping a cluster of vehicles in a station, the line
capacity through a station can be significantly increased over a
single-vehicle station. The clusters act as virtual trains thereby
allowing high capacity.

Each zone controller is responsible for allocating and releasing
movement permissions for targets within its borders. The target
"release" mechanism is set up with brick-wall inter-cluster headway and
safe-follower intra-cluster headway, as illustrated in Fig. 7.2. This
kind of operation allows for a level of safety similar to that of long
trains. In such a cluster one can associate each vehicle with a car of a
virtual train. If the highest level of throughput is not necessary,
"brick-wall" headways may be used between all vehicles. The target
concept is easily tailored to either headway type, and may even be
changed dynamically for higher throughput during times of peak load.

![](media/image25.wmf){width="5.623611111111111in"
height="1.3958333333333333in"}

[]{#__RefHeading___Toc89856188 .anchor}Fig. 7.2. Two clusters of
vehicles.

### Advantages of proposed design

The MagneMotion control scheme is able to meet high throughputs in a
safe manner while respecting the one vehicle per block limitation. It is
flexible in terms of the headway strategy used and is easily expandable.
Through proper target placement the algorithm supports such design goals
as sub-block switching and can limit the loading of support structures
by limiting the number of vehicles on a particular track section. The
scheme, through proper placement of targets, can also support stopping
only at egress points along the guideway. This system is fail-safe in
the sense that when a controller or a communication link is not
operational, new targets are not granted and the vehicles come to a stop
at their last acquired targets.

### Advanced operational strategies

To exploit the full capability of the transport system, certain
strategies may be used. In a high-speed urban system with on-line
stations it will be necessary to use multi-bay stations to achieve
desired throughput, as shown in section 7.5.2.

High-level control strategies may be layered on top of an existing
control system by the central controller or at the track layout stage of
design. For instance, faster travel may be achieved by using strategies
such as selective station servicing, where every vehicle does not stop
at every station. Each vehicle may, for instance, service two out of
every three stations, with different vehicles serving different sets of
stations. A passenger can still move from his origin to his chosen
destination by selecting the correct vehicle or by changing vehicles.
Since fewer stops are required, shorter travel time may be achieved.
Also, demand-based station servicing may be used. For instance, vehicles
may skip stations where there is no demand (which would require
knowledge of the destination of each passenger).

## Simulation

Preliminary simulations were performed to examine the basic limitations
of the system. One such limitation is line throughput -- the maximum
capacity of the line. Using some basic assumptions, it was discovered
that with a safe-follower headway the line has a capacity beyond the
goal of 12,000 passengers per hour per direction (pphpd). The next most
significant limitation investigated was throughput limitations of the
stations, as they were assumed to reside on-line. The simulations
described below focus on the limitations presented by the necessity to
stop at on-line stations. With certain operational strategies, the
simulations showed that the target throughput could be met with on-line
stations.

### Assumptions

The assumptions for the simulation are summarized in Table 7.1.

Table 7.1. Simulation Assumptions.

  ------------------------------------------- ---------------- ----------
  *Item*                                      *Value*          

  Max Acceleration                            1.6              m/s­^2^

  Station Type                                On-line          

  Headway Type                                "Safe"           

  Dwell Time                                  15               s

  Block Length at stations                    18               m

  Max Velocity                                45               m/s

  Vehicle Occupants                           36               
  ------------------------------------------- ---------------- ----------

The simulations were performed based upon a crude model of the control
system previously described. The stopping place for each vehicle, a
"bay", was assumed to be at the end of a block within the station. The
assumed acceleration was based upon passengers standing in the vehicle
to achieve maximum capacity. The throughput improves if the blocks are
shortened due to the constraint of one vehicle per block constraint.
Most of the benefit of shortening blocks is achieved with a block length
of 18 meters but additional capacity is possible with shorter blocks
within stations.

### Results

Preliminary simulations were performed with a range of one to five bays
per station. It was assumed that for multi-bay stations, a fleet of
vehicles would move into the station, dwell, and leave the station. A
cluster of vehicles stops at a sequence of bays in the station. To
calculate throughput, the time was calculated from the start of the exit
of one cluster of vehicles to the arrival of the next. This time was
added to the station dwell time to realize the total time that the
cluster occupied the station. From this value, the average throughput
may be calculated. Figure 7.3 illustrates a scenario with 4 bays and 6
vehicles. As the first fleet of four exits, the next vehicles enter and
stop at the first two bays in the station.

![](media/image26.wmf){width="4.9375in" height="3.2083333333333335in"}

[]{#__RefHeading___Toc89856189 .anchor}Fig. *7*.3. Typical Simulation of
a 4 bay station with 6 vehicles.

A summary of the results is shown in Fig. 7.4. A minimum of four bays is
required to achieve the desired capacity of 12,000 pphpd. Selective
stopping strategies may further enhance throughput, or reduce the
required number of bays.

![](media/image27.wmf)

[]{#__RefHeading___Toc89856190 .anchor}Fig. 7.4. Station throughput as a
function of the number of bays.

### Conclusions

The primary conclusion is that a throughput of 12,000 pphpd is
achievable under certain assumptions using the control system concept
described. The line is able to meet the capacity when using a
"safe-follower" headway between vehicles of a cluster and 'brick-wall"
headway between clusters. The stations are able to meet this throughput
through the use of multiple sequential bays per station.

# Demonstration prototype

The key suspension and propulsion design concepts have been tested by
constructing the demonstration prototype shown in Fig. 8.1. This first
generation prototype uses full-scale magnets but the vehicle is shorter
and narrower than the vehicles described earlier. The prototype is fully
functional, and has met its design objectives. The agreement between
predicted and measured quantities ranged from fair to very good. The
computer models used to design the demonstration system correctly
predict the system behavior with good accuracy so it is reasonable to
expect similar validity for the models of the full-size system.

![](media/image28.png)

[]{#__RefHeading___Toc89856191 .anchor}Fig. 8.1. Photograph of prototype
vehicle and guideway.

## Static load test results

Table 8.1 gives data that is exemplary of the many measurements made and
shows the relatively good agreement with predictions. Prototype testing
involved a much wider range of load than is planned for a full-scale
vehicle, so in normal operation the range of gap variation about the
nominal value will be smaller (only about ±3 mm) than the range shown in
Table 8.1. This data is for the initial prototype before the addition of
lateral damping. The modified prototype is described later and has a
higher lift force.

The operating gap of the nominally loaded vehicle is 0.6 mm larger than
the predicted 20 mm gap. This deviance from the analytical model is due
to the strength of the magnets. The incoming inspection data to measure
the field strength of the raw magnets showed that the magnets generally
had a higher field strength than the nominal value used in the FEA
models. The effect of the stronger magnets can be seen in the test data,
in this and subsequent sections, in the form of higher forces and a
wider operating gap.

The power required to levitate the vehicle is very small, and the
static, disturbance-free conditions in the laboratory accentuate this
feature, resulting in the very small power requirements shown in Table
8.1. In a more realistic operating environment with disturbances due to
wind gusts and guideway deflections, we estimate the levitation power
requirement to be 100 W per Mg (i.e. tonne) of levitated mass.

Table 8.1. Static performance of initial demonstration prototype.

+-----------+-----------+-----------+-----------+-----------+--------+
|           | *Gap*     | *Gap*     | *Mass*    | *Mass*    | *Lev*  |
|           |           |           |           |           |        |
|           | *         | *         | *         | *         | *      |
|           | (design)* | (actual)* | (design)* | (actual)* | power* |
+-----------+-----------+-----------+-----------+-----------+--------+
| Light     | 25 mm     | 24.6 mm   | 734 kg    | 777 kg    | 2.0 W  |
+-----------+-----------+-----------+-----------+-----------+--------+
| Nominal   | 20 mm     | 20.6 mm   | 958 kg    | 981 kg    | 2.0 W  |
+-----------+-----------+-----------+-----------+-----------+--------+
| Heavy     | 15 mm     | 15.8 mm   | 1284 kg   | 1229 kg   | 2.3 W  |
+-----------+-----------+-----------+-----------+-----------+--------+

The guideway is 6 m long and allows a vehicle to move 3.9 m. With a
nominal load of 981 kg the maximum test speed was 1.74 m/s (3.8 mph)
with an acceleration of 2 m/s^2^. Figure 8.2 shows some of the component
detail of the second generation test vehicle.

![Figure 8.2 shows a rendering of the prototype vehicle. Levitation
controller assemblies are mounted on the slanted side of the vehicle in
metal boxes. Arrows point to parts on the front and bottom of the
vehicle describing lateral guidance devices, position transducers,
levitation assemblies, and additional
batteries.](media/image29.png){width="4.480708661417323in"
height="3.15748031496063in"}

[]{#__RefHeading___Toc89856192 .anchor}Fig. 8.2. Maglev test vehicle.

## Lateral stiffness test results

The lateral stiffness of the suspension system was measured with the
apparatus shown in Fig. 8.3. The levitated vehicle is displaced
laterally via a leadscrew, cable, and pulley arrangement. The lateral
force required to displace the vehicle is measured with a strain gauge.
The results of this test series are shown in Figure 8.3. As expected,
the lateral force increases roughly in proportion to the lateral
displacement. The stiffness associated with this relationship is 101
N/mm. The measured data agrees in form with the predictions of the FEA
model, but the measured data shows approximately 10% larger forces due
to the magnet field strength being greater than assumed in the FEA
model.

![](media/image30.wmf)

[]{#__RefHeading___Toc89856193 .anchor}Fig. 8.3. Lateral displacement
test setup.

![](media/image31.wmf){width="4.175694444444445in"
height="2.6666666666666665in"}

[]{#__RefHeading___Toc89856194 .anchor}Fig. 8.4. Lateral stiffness
measurement results.

## Lateral damping test results

For our second generation test vehicle a key objective was to
demonstrate lateral damping using active control coils. Four tasks were
necessary to achieve this objective.

1.  Analyze lateral damping dynamics and determine requirements.

2.  Modify the integrated propulsion and levitation pods of the original
    demonstration system to include active magnetic damping of lateral
    motion.

3.  Develop active controls for levitation and lateral damping.

4.  Confirm the analysis and lateral damping performance.

The lateral damping mechanism facilitates damping of the yaw and sway
axes, thus enabling the levitation controller to damp vehicle movements
in yaw, pitch, sway, roll and heave.

### Analysis 

The implementation of an actively controlled electromagnetic damping
mechanism required a comprehensive magnetic analysis effort. Several
objectives must be met to successfully complete the magnetic design of
the levitation assembly for the demonstration system. First, we
determined the lateral force capability needed to provide adequate
damping of the lateral vehicle dynamics. Next, we determined the
levitation assembly configuration required to yield the desired lateral
force. Lastly, we determined the optimal magnet dimensions to minimize
force and pitch variations. Each of these objectives is discussed in the
following sections.

### Lateral force requirements

The analysis in this section determines the lateral force capability
required to provide adequate lateral damping of the demonstration
vehicle. The lateral guidance force for the demonstration system
is$F_{z} = - \text{65}z - 0\text{.}\text{0195}z^{3}\text{ N}$ and the
vehicle mass is 1275 kg.

The lateral dynamics of the demonstration system, with a damping force
of $F_{z} = - 9\text{.}1\frac{\text{dz}}{\text{dt}}N$ are shown in
Figure 8.5. The response is well behaved, with an overshoot of
approximately 17%. The lateral dynamics of the demonstration system,
with a damping force of
$F_{z} = - \text{13}\frac{\text{dz}}{\text{dt}}N$, are shown in Figure
8.6. The response is well damped, with an overshoot of only 4%.

The maximum lateral displacement for the vehicle is 40 mm. The recovery
transient from this initial displacement would require a peak lateral
damping force of 1718 N for the model used for Fig. 8.5, and a peak
lateral damping force of 2093 N for the model used for Fig. 8.6. Both of
these peak force requirements are quite large, considering that the
system will rarely operate with such an extreme lateral transient. If
the system from Fig. 8.5. is operated with a maximum lateral damping
force limit (i.e. a \'clipping\' or \'saturation\' type limit) of 910 N,
the response shown in Fig. 8.7 is the result. The first overshoot is
larger, due to the saturated nature of the damping force, but the
response then quickly settles in a well-behaved manner. Thus the most
extreme displacement is damped by a factor of two in the first
overshoot, and then settles in an unsaturated manner. This behavior is
quite acceptable, and substantially reduces the peak damping force
requirement from the unsaturated case in Figure 8.5. Figure 8.8 shows
the transient response of the system of Fig. 8.6, but with the same
maximum lateral damping force limit of 910 N. Once again, the extreme
initial displacement is damped by a factor of two on the first
overshoot, and then settles in an unsaturated manner.

![](media/image32.wmf){width="4.292361111111111in"
height="2.6979166666666665in"}

[]{#__RefHeading___Toc89856195 .anchor}Fig. 8.5. Lateral dynamics with
K~v~ = -9.1 N/(mm/sec) × dz/dt

![](media/image33.wmf){width="4.292361111111111in"
height="2.6979166666666665in"}

[]{#__RefHeading___Toc89856196 .anchor}Fig. 8.6. Lateral dynamics with
K~v~ = -13 N/(mm/sec) × dz/dt.

![](media/image34.wmf){width="4.292361111111111in"
height="2.6979166666666665in"}

[]{#__RefHeading___Toc89856197 .anchor}Fig. 8.7. Lateral dynamics with
K~v~ = -9.1 N/(mm/sec) × dz/dt, force limit of 910 N.

![](media/image35.wmf){width="4.292361111111111in"
height="2.6979166666666665in"}

[]{#__RefHeading___Toc89856198 .anchor}Fig. 8.8. Lateral dynamics with
K~v~ = -13 N/(mm/sec) × dz/dt, force limit of 910 N.

In conclusion, a maximum lateral damping force capability of 910 N (or
455 N per pod) is required to adequately damp the lateral dynamics of
the demonstration system. A damping force coefficient in the range of
--9.1 to --13 N/ (mm/sec) yields a well-behaved transient response. A
choice towards the top of this range will provide the benefit of a
smaller overshoot at the expense of more control power for a given
disturbance spectrum. Since the value of this coefficient is a software
feature, it may be easily selected within this range based on the
operating environment of the system.

### Lateral Dynamics test results

The dynamic response associated with lateral movement was measured to
verify the analytical results. An inductive position sensor was placed
in proximity to the side of the vehicle, thus allowing the lateral
position of the vehicle to be measured and recorded on an oscilloscope.
The vehicle was pulled laterally to an offset position, and then
released to examine the step response of the suspension system to
lateral disturbances. The results of this test are shown in Figs.
8.9-11. Figure 8.9 shows the step response to a lateral disturbance with
the controller coefficients set to provide no lateral damping. As
expected, this plot shows a very lightly damped response with a natural
frequency of approximately 1.17 Hz. Figure 8.10 shows the lateral step
response with the controller coefficients set for a lateral damping
force of approximately -10 N/(mm/sec). There is a marked improvement in
the system damping, but the response is not as well damped as predicted.
Observation of the vehicle motion reveals that the roll mode of the
vehicle is also being excited in this response. Analytically, this makes
sense; the lateral damping force is applied at the suspension gap, which
is approximately 200 mm below the center of gravity of the vehicle.
Thus, the lateral damping force causes a torque about the roll axis of
the vehicle, which excites the roll mode.

Figure 8.11 shows the lateral step response of the vehicle with the
controller coefficients set for a lateral damping force of -10 N/
(mm/sec), as well as a compensating roll torque to null out the effect
of lateral force on the roll axis. The response is improved, showing a
very well damped behavior. Observation of the vehicle motion during the
transient reveals that there is still a roll axis excitation. The roll
and sway (lateral) axes are coupled through the lateral stiffness force
measured in the previous section. Since this force, like our lateral
damping force, is applied at the levitation gap which is below the
center of gravity of the vehicle the roll and sway axes are dynamically
coupled to one another. This coupling is not a problem in practice since
all of the vehicle modes are well damped. The coupling merely makes the
isolation and laboratory measurements of the response of a particular
mode difficult.

![](media/image36.wmf){width="6.002083333333333in"
height="3.821527777777778in"}

[]{#__RefHeading___Toc89856199 .anchor}Fig. 8.9. Lateral step response
with no damping.

![](media/image37.wmf){width="6.002083333333333in"
height="3.821527777777778in"}

[]{#__RefHeading___Toc89856200 .anchor}Fig. 8.10. Lateral step response
with lateral damping.

![](media/image38.wmf){width="6.002083333333333in"
height="3.8118055555555554in"}

[]{#__RefHeading___Toc89856201 .anchor}Fig. 8.11. Lateral step response
with lateral damping and roll torque compensation.

## Magnet optimization

The configuration of the end magnets was optimized to minimize the
variation of the pitching moment, while also retaining a small cogging
force. In addition, the end magnet configuration must conduct half of
the flux from a full magnet to ensure that the flux is distributed
evenly throughout the vehicle back iron. To accomplish these objectives,
the end magnet width (in the longitudinal dimension), thickness (in the
vertical dimension), and spacing relative to the full magnets were
varied. The optimization process was conducted on a 2D model, since it
was determined that more than a year of compute time would be required
for optimization on a 3D model. A set of scripts allowed adjustment of
one of the variable parameters, while holding the other two parameters
constant. The scripts were run iteratively to search for the optimal
solution.

## Conclusions

The first generation prototype demonstrated that our design methodology
was sound and all critical parameters agreed with predictions within a
few percent. The first test vehicle was modified with the principal
objective of demonstrating active lateral damping and reduced pitching
due to end effects. The resulting second generation test vehicle met all
expectations and MagneMotion is confidant that when the design is scaled
up to a full size vehicle the performance will meet our objectives.

# Application examples

Different applications require different design strategies to achieve
optimum performance. The following Sections give typical design
parameters for four types of applications that span a wide range.

The performance for a typical trip of 3.2 km (2 miles) is shown in Fig.
4.3. This Figure shows the velocity vs. time based on a simulation for
the LSM and vehicles described in this paper. The LSM is capable of
acceleration and braking at a rate of 2 m/s^2^ for a nominal load. For
normal operation the acceleration and braking are limited to 1.6 m/s^2^
in order to limit the forces on standing passengers. At higher speeds
the motor inductance and aerodynamic drag limit acceleration. Fig. 4.2
shows that with regenerative braking the average LSM power requirement
is 65 kW for a typical mission.

From Fig. 4.3 it can be concluded that the travel time is 30 seconds
more than it would be if the acceleration and braking were
instantaneous. For example, a trip of 3,200 m requires a travel time of
3,200/45 + 30 = 101 seconds. Assuming 20 seconds for dwell time to
unload and load passengers the trip takes 121 seconds for an average of
26 m/s (59 mph). This is optimistic because it neglects possible
increases in time due to hills and turns, but it shows the potential of
the *M3* system. This time estimation method has been used to arrive at
the average speeds given in the following discussions of applications.
It is recognized that many other factors will affect performance so the
speeds given here are probably somewhat higher than might be realized in
practice.

## Shuttle

There are many examples of Automated People Movers (APM) used for
shuttling passengers a short distance, such as within an airport or from
a parking lot to an arena. This example assumes a much higher speed than
would normally be used for such an application, but the speed has very
little impact on cost and may even lower it.

### Design problem

Design a 1-mile long shuttle for moving 12,000 people per hour per
direction (pphpd) at speeds up to 45 m/s (101 mph). Assume a maximum
capacity of 40 passengers per vehicle and dwell time of 48 seconds for
unloading and loading. The design should minimize life-cycle-cost of the
vehicles and propulsion system.

### Conventional solution

Use light-rail with a top speed of 45 mph and acceleration limit of 0.8
m/s^2^. The propulsion is by vehicle based motors, either rotary or LIM,
with power transferred to the vehicle via an overhead catenary. A
typical design uses a train of 2 vehicles, each of which is articulated
for sharper turns. The empty weight of each of the vehicles is 40 tons.
For this heavy train it is economically prohibitive to use higher
acceleration or speeds. The result is the need to use a larger number of
trains and to increase passenger trip time as compared with what is
possible with *M3*. The use of smaller vehicles would require headways
that are too short for conventional control systems. LIM propulsion of
wheeled vehicles has more reliable traction than rotary motors but it
would increase cost and not allow as short a headway as is possible with
an LSM.

### M3 solution

The baseline vehicle carries no propulsion or control equipment so it
can be light and relatively inexpensive. The light weight makes higher
acceleration feasible and this makes higher top speeds useful. LSM
propulsion can allow short headway between adjacent vehicles without
risk of accident because the propulsion does not depend upon adhesion
and the control has precise position information at all times and, most
important, it does not depend upon communication with a moving vehicle.
In order to allow stopping without offline loading the vehicles are
operated in clusters with sufficient headway between clusters to allow
unloading and loading one cluster before the next cluster arrives. Each
vehicle in a cluster has its own stopping place so the cluster acts as a
virtual train, but without the guideway and propulsion requirements to
support and power a physical train.

Because the trip is short the vehicles are configured with fewer seats
so as to allow 40 passengers without exceeding the weight limit. Five
vehicles are organized as a cluster with one cluster departing from each
end every 60 seconds so as to achieve the desired capacity. The
individual vehicles operate with headways as short as 4 seconds. At each
end of the trip the vehicles negotiate an 18.3 m (60') radius turn. In
order to maximize capacity it is important to minimize dwell time. The
best way to do this is to use 2 doors and to unload and load at
different locations. The unloading is done in 24 seconds and the loading
is done after the vehicle negotiates the turn in another 24 seconds.
Each vehicle takes 240 seconds for a complete round trip so 4 clusters,
or 20 vehicles, are required to provide the desired capacity. The travel
time is 65 seconds and with a cluster leaving from each end every 60
seconds the average wait time is 30 seconds. The average trip time is
thus 95 seconds giving an average trip speed of 17 m/s (38 mph, 61
km/h). There are almost always some vehicles accelerating or cruising
while others are decelerating so it is possible to use virtually all of
the regenerated energy.

### Variations

The length could be changed and intermediate stops could be added. If
capacity requirements are reduced there do not need to be loops at each
end and single clusters of vehicles could shuttle back and forth on each
side, similar to conventional shuttle designs but with faster travel
time and increased capacity.

There is presently a plan to install a 3-mile shuttle from Oakland
Airport to the BART Coliseum Station with up to 2 intermediate stops. An
*M3* system could provide the required throughput with almost a factor
of two reduction in travel time and vehicle capacity and with a saving
in guideway and energy cost. With conventional technology the projected
cost of the shuttle is almost \$300 million while an *M3* system would
cost less than half as much.

## One-way loop

With a high top speed it is feasible to use a 1-way loop for distances
up to several miles. This reduces cost and minimizes the visual impact
of the guideway.

### Design problem

Design a 4 km long 1-way loop that can carry at least 3,600 pph at
speeds up to 30 m/s (67 mph). There should be 4 stops, a main stop and 3
satellite stops. Most people will be traveling between the main stop and
a satellite but a significant number will be traveling between 2
satellite stations.

### Conventional solution

A monorail propelled by rotary motors is a common solution. An
alternative is a cable propelled system such as ones being built by Otis
and Doppelmayr. These can be less expensive than light rail but average
speeds are typically less than 10 m/s (22 mph, 36 km/h) and capacity is
usually less than 3,000 pphpd.

### M3 solution

The short distance and necessity of turning in a moderately short radius
makes a top speed of 30 m/s (67 mph) about all that can be useful. This
reduces cost of the propulsion system at the expense of using more
vehicles, but for the required capacity the number of vehicles is fairly
modest. Cost and travel time are both reduced by using a station
skipping strategy. Vehicles are operated in clusters of 3 but each
vehicle skips one satellite station on each passage around the loop.

The time allowance for traveling 1 km is 55 seconds and for a 2 km trip
it is 90 seconds. Dwell time allowance is 50 seconds at the main station
and 40 seconds at the satellite stations. By using 3 clusters of 3
vehicles each there are 120 vehicle round-trips per hour. With 36
passengers per vehicle this provides a system transport capacity of
3,888 pph. The average time between clusters is 100 seconds and the
minimum vehicle headway is 4 seconds. There are always some vehicles
accelerating or cruising while others are decelerating so it will be
possible to use virtually all regenerated energy.

### Variations

If required at a later time, the capacity can be increased by adding an
additional vehicle to each cluster without any other change except to
increase the capacity of the rectifier station. By giving up the station
skipping strategy it is possible to add an additional cluster for still
higher capacity.

It is instructive to compare an *M3* system with the new \$650 million
Las Vegas Monorail. This state-of-the-art monorail has a dual guideway 4
miles long with 6 intermediate stops. Nine 4-car trains, each with a
capacity of 72 seated and 152 standing and operating with 2-minute
headway provide a capacity of 6,720 pphpd. The maximum speed is 45 mph
but travel time from one end to the other is 14 minutes so average
travel speed is only 17 mph. An *M3* system with greater capacity would
cost on the order of \$120 million plus the cost of stations, and reduce
end-to-end travel time to 6.5 minutes. There would be 42 40-passenger
vehicles operating in 3-vehicle clusters with 60 second headway between
clusters and a capacity of 7,200 pphpd.

## Airport connector

### Design problem

Design a high speed transit system to carry people between an airport
and city center. The travel distance is 30 km and the objective is to
minimize travel time without exorbitant cost.

### Transrapid maglev solution

This example is based on the Transrapid installation in China that is
now carrying passengers from Pudong Airport to Shanghai, a distance of
30 km. The top speed is 119 m/s (267 mph, 430 km/h), the travel time is
8 minutes, train headway is 10 minutes and average trip time is 13
minutes. There are three 5-car trains capable of carrying 574 passengers
each for a capacity of 3,444 pphpd. The reported cost of the Shanghai
installation is \$1.2 billion or about \$60 million per dual guideway
mile. The high cost is due to the heavy trains (260 Mg each), very heavy
guideway (7.7 Mg/m), high power inverters (estimated to be 7.2 MVA per
inverter), and the mass of the suspension rails (twice the width of the
rails used by *M3*). The suspension uses electromagnets which require
more than 1 kW/Mg and there are separate guideway-mounted guidance rails
and onboard magnet structures on each side of the trains. The guidance
system causes substantial power loss at high speeds, in some cases
comparable to the suspension loss. Sliding contact power transfer is
used to provide onboard power for speeds up to 22 m/s (50 mph, 80 km/h)
so some of the contact-free advantages of maglev are not achieved.

### M3 solution

The *M3* design delivers comparable performance at much lower cost. The
maximum speed is assumed to be 60 m/s (134 mph). Although higher speeds
are possible, this example shows that the lower top speed but higher
acceleration and shorter vehicle headway gives comparable performance to
Transrapid for trips of this length. Since the top speed is only one
half that of Transrapid, the guideway layout can tolerate a factor of 4
reduction in turn radii and the guideway beams need not be as stiff or
precisely aligned, so guideway cost can be reduced. The cost of the
power system and the energy consumed are both reduced by a large factor.
Inductive power transfer is used at all speeds so the cost and
maintenance issues associated with sliding contacts are avoided.

The proposed design uses a 3-vehicle cluster with minimum headway of 4
seconds near the stations and 10 seconds in the high speed regions.
There are 3 stopping places at each end so each vehicle in the cluster
has a unique stopping place. Since the trip is long it is preferable to
not have standees so the vehicle is configured to have 36 seated
passengers and no standees. A cluster leaves every minute for a capacity
of 5,760 pphpd with an average travel time of 9 minutes and an average
trip time of 9.5 minutes. At a later time a 4^th^ vehicle could be added
to each cluster to increase the capacity to 7,260 pphpd with no change
in minimum headway. Each vehicle makes a round trip in 20 minutes, so
there are 20 clusters for a total of 60 vehicles. The vehicles seat a
total of 1,920 passengers, giving a passenger capacity per seat that is
50% higher than Transrapid, and the vehicles are much less expensive on
a per-seat basis.

The guideway has a loop at each end. This allows the vehicles to be
designed for unidirectional operation with reduced aerodynamic drag. The
option of using a switch and bidirectional vehicles is possible, but
this would entail the use of more vehicles for the same capacity and
does not allow some of the advantages of unidirectional vehicles. For
Transrapid the minimum turn radius is so large that they need to use a
switch and bidirectional vehicles.

There are always enough vehicles accelerating or cruising to absorb all
regenerated braking energy, but the energy savings are a much smaller
percentage of energy usage because the trips are long and fast

## Intercity

The focus of the *M3* development has been on urban maglev with maximum
speeds in the range 30-60 m/s (67-134 mph), but the suspension and
propulsion systems are capable of much higher speed with no change in
the basic design. We can envision a higher speed intercity maglev system
that uses the same guideway as urban maglev for distribution of
passengers in urban environments, just as high speed rail uses low speed
tracks for operation in cities. The key is to make the high and lower
speed designs interoperable so that all vehicles can traverse the same
guideway, albeit with the speed and thrust limits determined by a
combination of vehicle and guideway attributes. Although the *M3*
technology is almost certainly capable of speeds as high as Transrapid,
we feel that for U.S. applications the most cost-effective design is for
a top speed in the range 75-90 m/s (168-202 mph, 270-324 km/h), the same
range as for existing high speed rail.

Following are the major changes required to make the *M3* design
competitive with high speed rail:

-   *Increase vehicle length*

At high speeds the aerodynamic drag becomes a dominant parameter and the
per-seat drag is reduced by using longer vehicles with more seats and
better nose and tail streamlining. Longer vehicles also allow more
comfortable seating and room for toilets and vending machines. With
longer and faster vehicles it is economically feasible to have cabin
attendants to deal with a variety of issues that arise on longer trips.
The longer vehicle is constructed by using 6 or 8 magnet pods and a 2 or
3 section articulated vehicle for 60-100 seated passengers.

-   *Increase guideway stiffness:*

This can be done by decreasing pier spacing (e.g. use 24 m pier
spacing), increasing beam stiffness, or some combination.

-   *Increase vehicle and cluster headway times:*

The longer and faster vehicles will require greater headway between
vehicles, on the order of 6 seconds for a speed of 75 m/s (168 mph).
Since vehicle travel is likely to be scheduled it is not necessary to
have as short a time between clusters so cluster spacing should be about
4 minutes. This long spacing between clusters will allow offline loading
and unloading and thereby allow a mixture of express and local service
to use the same guideway. It will also allow long enough clusters to
achieve a capacity of at least 8,000 pphpd.

-   *Increase per-vehicle propulsive power*

The heavier and faster vehicles will require higher propulsive power per
vehicle. For long distance travel there are good reasons to reduce peak
thrust to about 1.6 *g* but the peak power per-vehicle will need to be
increased. This might be done by increasing the DC bus voltages to
±1,500 VDC and using readily available, higher voltage IGBTs. The number
of turns in the winding do not need to be changed. Shorter low speed
vehicles will be able to operate on a high speed guideway with thrust up
to 1.6 *g* and longer high speed vehicles will be able to operate on a
low speed guideway at reduced speed.

-   *Increase guideway and vehicle tilt*

Higher speed capability is better utilized if the vehicle can tilt while
negotiating turns so as to allow more versatility in following available
rights-of-way. A guideway tilt of 10º and a vehicle tilt of 7º will
allow a vehicle to make a 1.5 km (0.9 mile) radius turn at 75 m/s (168
mph).

The sum total of all of these changes would increase the system cost by
10-25% depending upon the maximum speed and other parameters, but it
would still be substantially less expensive than a new installation of
high speed rail or Transrapid maglev. It could be constructed over
existing rail lines thereby allowing the existing rails to be used
exclusively for freight. With relatively high acceleration and tilt
capability it is possible to negotiate the turns required to follow a
rail line at high speed without losing too much time slowing for turns.

As a specific example, the *M3* design is a suitable replacement for
CHSST for the Colorado Maglev Project as reported in documents
accessible at
<http://www.dot.state.co.us/publications/maglev/maglev.htm>. We would
propose use of a 75 m/s (168 mph) top speed, more use of point-to-point
express scheduling, and vehicle tilting so as to increase the average
speed from Chubu's estimate of 31.7 m/s (71 mph) to at least 45 m/s (101
mph). We have not worked out details of vehicle and guideway design so
as to be able to give reliable data on energy consumption but are
confident that we can provide faster travel at no higher energy or
dollar cost than for a CHSST system.

MagneMotion does not advocate a high speed intercity application for an
initial installation but would like to avoid making design decisions
that preclude the evolution of a maglev system that has the versatility
of conventional rail and allows a wide range of speeds. We believe that
*M3* has greater versatility than Transrapid and will turn out to be a
more cost effective design for all speed ranges of interest in the U.S.

## Summary

The four examples represent very different types of applications, all
served by common suspension, propulsion and guideway designs. The
vehicles for any one system could operate on the other systems with
modified performance.

Table 9.1 gives a comparison of some of the performance predictions. The
average power is for the time the vehicle is moving and the energy usage
assumes full use of regenerated energy and a 50% passenger load factor.
The Intercity example has not been worked out in enough detail to give
energy consumption details.

*Table 9.1. Comparison of four examples of M3 applications.*

+------------------------------+---------+---------+---------+---------+
|                              | *S      | *Loop*  | *A      | *Int    |
|                              | huttle* |         | irport* | ercity* |
+------------------------------+---------+---------+---------+---------+
| Capacity, pphpd              | 12,000  | 3,600   | 4,300   | 6,000   |
+------------------------------+---------+---------+---------+---------+
| Maximum speed, m/s           | 45      | 30      | 60      | 75      |
|                              |         |         |         |         |
| mph                          | 101     | 67      | 134     | 168     |
+------------------------------+---------+---------+---------+---------+
| Distance, km                 | 1.6     | 4       | 30      | 250     |
+------------------------------+---------+---------+---------+---------+
| Stations                     | 2       | 4       | 2       | 17      |
+------------------------------+---------+---------+---------+---------+
| Average speed, m/s           | 25      | 20      | 35      | 45      |
|                              |         |         |         |         |
| mph                          | 55      | 44      | 78      | 101     |
+------------------------------+---------+---------+---------+---------+
| Average power , kW/veh       | 60      | 80      | 230     |         |
+------------------------------+---------+---------+---------+---------+
| Energy, J/pas-meter          | 524     | 400     | 814     |         |
|                              |         |         |         |         |
| BTU/pas-mi                   | 843     | 644     | 1,310   |         |
+------------------------------+---------+---------+---------+---------+
| Regeneration energy savings, | 50      | 45      | 6       |         |
| %                            |         |         |         |         |
+------------------------------+---------+---------+---------+---------+

For comparison, the Transportation Energy Data Book: Edition 23 (Oak
Ridge National Laboratory, October 2003, available at:
http://cta.ornl.gov/data/) gives the following energy intensities in
BTU/pas-mile for conventional transit in 2001: commuter rail 2,717; rail
transit 3,114; transit bus and trolley bus 4,125; Amtrak 4,127. This
reference assumed an electricity generation and distribution efficiency
of 29% so 1 kJ is equivalent to 3.268 BTU and this factor was used in
computing the BTU/pas-mi in Table 9.1.

Even allowing for substantial energy increases due to HVAC and other
loads, the LSM approach uses much less energy. This is due to kinetic
energy recovery, lighter vehicles and more efficient propulsion. Another
major source of energy conservation is the ability to fine tune vehicle
capacity to need and avoid using long and nearly empty trains for
off-peak travel.

# Cost estimates

This section develops estimates of the cost per mile for the *M3* Urban
Maglev System. Costs are compiled from information supplied by component
designers and manufacturers and have been confirmed by a second source
where possible. In a few instances there is not enough information to
make an accurate estimate, but all of the primary costs have been
determined after consultation with appropriate manufacturers and
vendors. MagneMotion will continue to refine the cost estimates as the
design evolves.

The cost estimates for all guideway related items are computed on a
per-unit-beam-length basis. The baseline design calls for double-span
beams that are 72 meters long. Each 144-meter length of guideway
contains the following:

-   4 72-meter long beams.

-   4 piers.

-   16 36-meter long LSM stators.

-   1 inverter station containing 8 inverters and associated switches
    and controllers.

-   1 hub controller and communication module.

-   Power cables for distributing DC and AC power

The DC power is provided by a rectifier station located every 8 km (4.97
miles), and each station contains a power transformer and rectifiers
that provide separate +900 and --900 VDC power with a total power rating
of 1.5 MW. The rectifier station may include a source of emergency
power, but this cost has not been included; a rough estimate is
\$100,000 added cost for every rectifier station for an automated 100 kW
DC generator.

Power station rating and spacing is consistent with operating 4 vehicles
per mile of dual guideway, so this is used as the nominal vehicle
requirement. If the average speed is 50 mph then the capacity is 3,600
pphpd. For different applications the number of vehicles per mile and
power station spacing and power could vary substantially. If smaller
and/or lower speed vehicles are used the cost of the vehicles and power
system will be somewhat lower.

The order of the costing section follows highest to lowest cost
components.

1\. Guideway

2\. LSM stator

3\. Power system

4\. Vehicles

5\. Controllers and software

The following sections discuss the basis of the cost estimates and a
summary is given in Section 10.6.

## Guideway

Guideway cost is based on our baseline design: a dual guideway with
double-span 72-meter long guideway beams and pier construction. The cost
estimate includes provisions for mounting the LSM and labor hours for
anchoring and aligning the LSM stators to the guideway beams. Pricing
assumes concrete guideway beams and piers.

A 25% contingency factor has been added in the expectation that
additional expenses will be necessary to meet installation and
operational requirements. Structural requirements have been met in the
preliminary investigations of guideway designs but operational dynamics
may dictate refinements to these designs. When a site is chosen guideway
optimization simulations will dictate full beam requirements.

Cost estimates are based on information supplied by Earth Tech of Long
Beach CA, and are based on their recent experience with installation of
the Vancouver Skytrain, and Bankok Transit system.

## LSM stator

The LSM stator is made up of two major components: laminations and
windings. Included in the LSM stator are the costs for mounting and
aligning the stator laminations and installing the windings. Lamination
estimates are by Tempel Steel assuming that the lamination stacks are
fabricated on site from stamped and spooled M19 24-gauge electrical
steel. Winding estimates are based on corporate experience with
producing and installing LSM windings. Although manufacturing methods
for the 3-phase windings have not been determined, wound on or off site
cost estimates are expected to be similar. A 15% contingency has been
included.

## Power system

Key components of the propulsion system are the inverters that transfer
power between the DC bus and the LSM windings. For the baseline design
it is assumed that there is an inverter station at every 4^th^ pier and
it contains inverters for driving the port and starboard motors for each
lane of a dual guideway for 72 meters in each direction. Near stations
where speed is low it is desirable to have a separate inverter for every
block, and possibly use shorter blocks, but in regions where the speed
is high each inverter can drive several blocks. We estimate that, on
average, there will be an inverter for every two 36-meter stator blocks.
The cost estimate includes the requirement for 3-phase power cables to
distribute the inverter output power.

Cost estimates are based on the following assumptions:

-   There is an inverter station every 144 meters and it contains 8
    inverters. Each inverter has a rating of 500 kVA and operates off of
    a 900 VDC supply. The maximum power output per inverter is 250 kW.

-   Each inverter contains a pair of 3-phase switches so it can provide
    power to either of two 36-meter long LSM sections.

-   Power is distributed by a 3-wire DC bus with voltages of +900, 0 and
    -900 VDC. The power cable is installed on one side of a dual
    guideway.

-   Rectifier stations have a rating of 1.5 MW and are located at 8 km
    (4.97 miles) intervals in each direction. Up to 2.25 MW is available
    for short periods.

-   Inverter pricing includes power modules and filtering but excludes
    control boards which are included as part of the control system
    cost.

-   Inverters have regeneration capability but no braking resistors.

-   Inverter cooling and heating is suitable for any U.S. urban
    environment.

Costs for the rectifier station and power cables are based on
discussions with Massachusetts Electric Construction Co. Inverter cost
estimates are based on discussion with Powerex and other semiconductor
manufacturers. Other costs are based on MagneMotion's experience in
designing and building LSM propulsion systems. A 15% contingency has
been added.

## Vehicle

The baseline vehicle can carry 24 passengers seated and 12 standees or
can be reconfigured to have 16 seats and 24 standees or 32 seats and no
standees, if these alternatives are better for specific installations.
Smaller and larger vehicles are possible but a detailed costing has not
been done for other vehicle sizes.

A secondary eddy current brake is planned for emergency use and a
tertiary mechanical brake is planned as an added safeguard but with the
expectation that it will never be used. No detailed designs have been
completed so only rough estimates are used for budgeting purposes. The
vehicle body estimates are based on discussion with Hall Industries, TPI
Composites Inc., CWA and others. The suspension component costs are
based on discussions with MagneMotion magnet and structural component
vendors.

The baseline vehicle has 4 magnet pods that include a secondary
suspension suitable for speeds to 45 m/s (101 mph) but with few changes
it could accommodate speeds up to 60 mps (134 mph). For speeds below 20
m/s (45 mph) the secondary suspension can be omitted.

Onboard power is provided by Inductive Power Transfer (IPT) from a
guideway power distribution system. The average onboard usage is
estimated at 12 kW average with up to substantially higher peak power.
This power rating is primarily based on HVAC needs and can be increased
if unusually hot or cold operating conditions are expected.

Preliminary estimates indicate that a 36-passenger vehicle will weigh
5.5 Mg empty and cost about \$800 thousand. For comparison, a typical
articulated light rail vehicle weights 40 Mg empty and costs about
\$2,500 thousand. The light rail vehicle has a crush load capacity of
about 200 passengers, but in typical operation it only takes three
36-passenger maglev vehicles to provide the same capacity as one light
rail vehicle because of the higher average speed. Thus total maglev
vehicle cost is comparable to the cost of light rail vehicles with the
same operational capacity, but maintenance and energy costs should be
much less. The improved speed and comfort for passengers should be
important selling points.

## Control electronics and software

The control system includes the central control and inverter controllers
located along the guideway. MagneMotion has developed very similar
controllers for other applications so we are confidant that the
estimates are valid.

## Cost summary

Table 10.1 summarizes costs in 2004 dollars of each major subsystem. It
is assumed that the installation is at least 10 km (6.2 miles) long with
the expectation that costs will be somewhat higher for shorter
installations. The estimated cost includes the contingency factors for
component parts, but does not include civil works, shipping, stations or
land acquisition costs.

Component contingencies account for uncertainties in our cost estimates
and are based on discussions we have had with various vendors regarding
the relative risk associated with the estimates. Even with the
contingencies, *M3* costs are well below those of competing transit
systems

Table 10.1. Total M3 system cost in k\$/mile assuming 4 vehicles per
mile.

  ---------------------------------------------------- -------------- --------
                                                       *k\$/mile*     *%*

  Guideway                                             10,131         37%

  LSM stator                                           7,539          27%

  Power system                                         5,102          18%

  4 Vehicles                                           3,172          11%

  Control electronics and software                     1,643          6%

  **Total cost per mile of dual guideway in k\$/mile** **\$27,587**   100%
  ---------------------------------------------------- -------------- --------

# Continuing development

Our system development plan consists of 4 phases. The first phase calls
for the construction of a 30 meter long indoor demonstration system in
MagneMotion's Acton MA facility. The vehicle for the indoor
demonstration system will be a test sled only. The outdoor demonstration
system will consist of a 200 meter track and a full-size vehicle.
Subsequent phases will incorporate a curve, switch, and finally, a
longer stretch of straight track to demonstrate vehicle control and ride
comfort at higher speeds. We have created a development plan and
prepared cost estimates for our expanded indoor test facility. In
parallel we are pursuing an outdoor location for the 200 meter track.
Our goal is to find a site where the 200 meter track will become part of
our first commercial installation.

## Expanded indoor test facility

The existing test track has allowed us to demonstrate the viability of
our design but it is too narrow and short to demonstrate key parameters
such as operation at higher speed, operation on a turn with a radius of
18.3 m, and block-to-block hand-off of the propulsion control. It is
desirable to develop final control systems in a controlled indoor
environment and this task is a first step towards developing the indoor
facility. The proposed indoor demonstration facility will include
approximately 24 meters of straight guideway and a 30º arc segment (9.6
meter arc length) of an 18.3-meter radius curve. The guideway will be
built with a full gauge rail spacing of 1.7 meters. The port and
starboard LSMs will have independent position sensing and inverter
drives. The guideway will be split into two blocks to allow for
block-to-block handoff. The vehicle will consist of full-scale
levitation assemblies, without secondary suspension. Although this
vehicle will be a \'sled\' with no shell, the size of the vehicle and
levitation assemblies will be the same size as those planned for a
12-passenger vehicle. Maximum travel stroke will be approximately 25
meters, including travel into the curved section.

## Site development

MagneMotion has initiated preliminary discussions concerning potential
sites for a test facility and an initial commercial installation. We
continue to pursue these leads with a focus on finding funding sources
and locations for high-speed testing. There have been ongoing
discussions with state agencies and government officials. We have an
outline of a preliminary proposal prepared for the Massachusetts Bay
Transit Authority for the use of property along side a railroad
maintenance facility in Cambridge, MA. We have had extended discussions
with Massachusetts Development, a private/public agency, that has been
tasked with the redevelopment of a former Air Force base. We also
continue discussions with other private institutions regarding the
replacement and extension of monorail systems, but are not free to
discuss details due to non-disclosure clauses.

Perhaps the most compelling site discussions we have had are those
involved with a plan to redevelop East Providence, RI. We believe this
application comes closest to meeting the FTA goal of building a
demonstration track that could become part of a commercial system.

The East Providence Development Project will require a public transit
system that will extend from Providence proper, through an existing
tunnel to the Seekonk River, over the river via an existing bridge, and
then extend 2 miles both east and west along the banks of the Seekonk
River. The initial phase of the transit system will be approximately 6
miles, with other extensions a possibility.

## Converging interests for East Providence Development Project

The FTA has indicated that their objectives for a funded project are
threefold: a maglev vehicle that can carry passengers, a travel distance
long enough for passengers to experience the ride quality of a maglev
system, and a demonstration site that can be tied to a future commercial
system. We believe this opportunity may meet all the FTA goals.

The following parties have an interest in establishing MagneMotion's
Urban Maglev System as the transit system of choice for East Providence,
Rhode Island.

### MagneMotion {#magnemotion .unnumbered}

MagneMotion is seeking a location to build its outdoor demonstration
system. The initial requirements call for a right of way at least 200
meters long and wide enough to construct an elevated guideway; a
facility that could house the vehicles, engineering lab, and perhaps the
first 20 meters of track; and a wide enough section of land at one end
of the right of way to construct an 18.3 meter radius curve. Additional
land would be needed to construct a switch, and to extend the line for
up to an additional 1,500 meters. The total development effort for the
indoor demonstration system and the 200 meter outdoor demonstration
system, including a full sized vehicle, curve and switch, is
approximately \$15 Million. The extended line would require additional
funding. MagneMotion is currently speaking with different investment
groups to raise a minimum of \$10 Million in order to complete the \$15
Million funding requirement. There is no assurance that additional
financing can be obtained. The prospects of receiving both an FTA grant
and private investment are significantly enhanced if a test system leads
directly to a commercial maglev system.

### East Providence Development Team (EPDT) {#east-providence-development-team-epdt .unnumbered}

EPDT is planning a major development project in East Providence that
would include residential, commercial, and industrial buildings. It is
believed that a public transportation system is essential for travel to
and from Providence proper, and up and down the banks of the Seekonk
River. In addition, EPDT would like to make this a high profile project
to create interest from investors, politicians, and potential tenants.
EPDT would also like to secure long term relationships with growth
companies that would establish manufacturing operations in the new
development.

### RI Economic Development Commission (RIEDC) {#ri-economic-development-commission-riedc .unnumbered}

RIEDC would like to attract industry and stimulate job growth in the
East Providence area.

### RI DOT {#ri-dot .unnumbered}

RI DOT would like to enhance public transportation, reduce traffic
congestion, and provide a solution to the transportation requirements
that would arise from a massive development project in East Providence.
RI DOT may have access to other sources of government financing

### RI Congressional delegation (RICD) {#ri-congressional-delegation-ricd .unnumbered}

RICD would like to enhance economic development in the State. RICD has
the ability to secure earmarked funds in the next budget for both
development and deployment. RICD also has the ability to strongly
endorse any FTA grant contemplated now or in the future.

### Private investors {#private-investors .unnumbered}

Private Investors would like their investment in Maglev augmented by
government grants, and assurances that a first installation that could
generate revenue and plant the seeds for a positive return on their
investment is near term. Equally as important, investors in EPDT would
like to ensure easy access to their development to ensure a high level
of occupancy and traffic to retail outlets.

### TPI Composites Inc. (TPI) {#tpi-composites-inc.-tpi .unnumbered}

TPI, a RI based company and a manufacturer of composite vehicles, has
been working with MagneMotion to design and build their Maglev vehicles.
Any efforts to bring MagneMotion's Maglev system to a commercial state
would greatly enhance TPI's business prospects. TPI is open to
relocating to East Providence and expanding its manufacturing
capabilities with the advent of a sizeable Maglev vehicle business.

## Action plan for East Providence

Public transit is an engine of economic growth in communities throughout
America. Creating development-orientated transit can boost and urban
maglev technology and encourage economic growth.   Our plan represents a
public/private partnership that meets the goals of stake holders in the
funding of public transportation, and the re-development of East
Providence.   MagneMotion will submit a proposal to the FTA. The
proposal will contain the first two phases of our development plan
mentioned above.  The corner stone of this plan will be the development
of a demonstration system in East Providence

# Conclusion

The *M3* project has met the objectives set out in the Introduction. The
resulting maglev system has applicability over a wide speed and distance
range. The key results of the design and prototype demonstration are as
follows:

-   Simplified suspension using permanent magnets with a 20 mm magnetic
    gap and only one set of magnets for suspension, guidance and
    propulsion.

-   Lightweight vehicles operated with high speed and acceleration take
    advantage of the maglev potential and lead to lower guideway and
    propulsion system cost.

-   Control using vehicle clusters with vehicle headway as short as 4
    seconds using the 'safe-follower" strategy and cluster spacing as
    required to achieve a "brick-wall" control between clusters for safe
    operation at all speeds. Clustering allows capacities of 12,000
    pphpd with 36 passenger vehicles.

-   Energy consumption is expected to be less than half that of
    conventional transit designs with comparable performance.

-   Reduced guideway size and minimal noise reduce environmental impact.

-   Cost for a complete system is approximately \$25 million per mile
    excluding vehicles, stations and land acquisition.

-   The design can be modified to use larger and faster vehicles so as
    to be competitive with high-speed rail and Transrapid maglev.

-   The performance of the design is accurately characterized by
    computer models and simulations so actual performance will be close
    to design expectations.

-   MagneMotion has high confidence that a commercial system will be
    competitive with all conventional guideway-based transportation
    systems.

# Acknowledgement

MagneMotion is pleased to acknowledge the many individuals, companies
and institutions that have contributed to the work described in this
report. We are especially appreciative of the FTA staff involved in the
Urban Maglev Project, including particularly Venkat Pindiprolu, Jim
LaRusch and Mary Anderson and their consultant Gopal Samavedam
(Foster-Miller). We thank Walter Eggers (EarthTech) and Scott Phelan
(Texas Tech) for their contributions to the guideway development. Pip
Shepley from Massachusetts Electric Contractors has contributed
to resolving guideway electrification  issues and Bob Wind and others at
TPI Composites Inc. have contributed ideas concerning vehicle design.