# Presentation: 944674

## Transit Priority Systems (TPS)

**Chun Wong, P.E.**
**City of Los Angeles, Department of Transportation**

- T3 Webinar

## “Smart” Transit Priority System (TPS)

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## Project Overview

- LADOT partnered with LA Metro in National Bus Rapid Transit (BRT) Demonstration Program since 2000
- Wilshire/Whittier & Ventura
- Strong Mayor commitment to improve LA transit services
- Improve bus run time performance
- Improve ridership
- Successfully implemented 18 Metro Rapid bus corridors and the Metro Orange Line
- Reduced 25% total travel time

## Project Objectives

- Provide schedule adherence
- Operate within existing street infrastructure
- Minimize cross street impact
- Provide bus arrival information
- Improve transit experience

## Existing Infrastructure

- City’s central Urban Traffic Control System (UTCS) - ATSAC
- One-second communication poll
- Type 2070 traffic controllers

## LA Transit Priority Systems Solution

- Transponder

- Loop Sensor

- 2070 Controller

- ATSAC Communication Network

## TPS Components

- Inductive loop/transponder detection
- Low frequency hockey puck liked transponder
- Curb-to-curb elongated loop sensor
- Model 2070 traffic controller
- Check-in / Check-out detection
- ATSAC communication network

## Transit Priority Manager

- Centralized System
- PC based server
- Real-Time
- Track vehicle positions
- Determine late/early
- Issue signal priority
- Calculate bus arrival
- Publish bus data
- Retrieve and data logging
- Implement TOD headway plan
- Non Real-Time
- Archive to database for trip analysis

## Preemption ≠ Signal Priority 

- Preemption
- Interrupt signal operations
- R x R crossings
- Emergency vehicles
- Signal Priority
- Modify signal operations
- Maintain coordination
- Borrowed time (10% of cycle length)

## Priority Treatments

- Early green
- Vehicle detection required
- Red truncation
- Green extension
- Vehicle detection required
- Extend green phase
- Most efficient priority
- Call Phase
- Left/Right turns

## LADOTTransit Priority Systems (TPS)

- Metro Rapid Bus

- Metro Orange Line

- Passenger Information System

- Transit Priority Manager

- Mobile Internet Passenger System

- Street Embedded Bus Sensor

- Transponder

- Graphics Display

- iTRAQ

## Multi-jurisdictional TPS

- Countywide BSP (Bus Signal Priority) Program
- WiFi 802.11b
- On-board GPS tracking
- Distributed system

## BI-Tran 2033 & L.A. TPS

## Slide 14

## TPS Map Client Software

**TPS Map Client Software**

- Bus Arrival Times

- Traffic Controller Status

- Bus Runtime Info

- Animated Bus Icons

## Passenger Information System

- Real-time data
- Integrated with TPM
- ETA Count down
- Lead bus’ travel time
- LED Displays
- Communication
- CDPD wireless by AT&T
- Obsolete
- Coverage
- Hard-wired FSK (Frequency Shift Keying)
- Traffic control device

## Headway Algorithm

- In-house developed
- High bus frequency service – low headway
- Leverages Hot List / Run List
- Time-point propagation (TPP)
- Load-balanced

## Mobile Internet Passenger Systems (MIPS)

- www.rapidbus.net

## TPS Real-Time Data Collection

- Signal Priority

- Real-time Graphical Displays

- Real-time Data Logging

- Transit Report And Query (iTRAQ) Web Server

- Transit Priority Manager
- (TPM)

## i Transit Report And Query

- Leverages existing TPS architecture
- Field equipment (Loop/Transponder AVL, 2070 Controller, etc.)
- Automates 24 x 7 transit trip data collection
- Weekdays; weekends; holidays; rainy days, etc.
- Uses commercially standardized Relational Database system (RDBMS)
- Oracle Database System
- Publishes through Web Server
- Simplify RDBMS data access
- Client workstations request no complicated ODBC and/or RDMBS setup
- In-house developed web application
- Microsoft IIS 6.0
- Performance Measure Tool

## iTRAQ Web Interfaces

## Lesson Learned

- Transit and DOT partnership
- Existing infrastructure
- Budget constraint
- Must / desire features
- Operating / Maintenance cost

## The End

- Questions & Comments
- Send questions to:
- Email: chun.wong@lacity.org