IMAGINE Robot Project

# Purpose 

The IMAGINE robot will provide an Access-Grid compatible roving
telepresence. It will enable people to remotely attend meetings that
would not otherwise be accessible to AG equipment, perform remote tours
of the Oakland HPC facility, and even enable LBNL-based personnel to
remotely assist/supervise remote reset and configuration of hardware in
the Oakland facility by the staff there. For more details, please visit
the project website at [http://dit.lbl.gov](http://dit.lbl.gov/). The
login for the \"private\" pages listed on this site is \"imagine\" and
the password is \"that!\".

## [Description]{.underline} 

The robot base will be approximately 33\" in diameter and 5\' tall. The
bulk of the robot will be located near the ground with the wheel-base,
but a mast will extend to approximately human height as a mounting point
for the robot\'s video-camera and a small LCD display (for the video
image of the remote user). The robot is constructed primarily from
off-the-shelf components in order to support long-term maintenance and
reliability of the robot platform.

### Motion Control

Typically robots use 2-wheel Akerman (tank-like) steering whereby
varying the relative speed of the two drive wheels controls the
direction of the robot. A 3rd swivel wheel provides stability for the
base. Such 3 wheel designs are inherently unstable and likely to tip
over if bumped. A 4-wheel design involving 2 drive wheels and 2 casters
is much more stable, but it is also susceptible to getting stuck on the
crest of even a moderate incline since one of the drive wheels will
likely be lifted off of the ground.

The IMAGINE robot uses 4 independently steered and motorized wheels in
order to provide extremely precise control over motion and to eliminate
the stall problem on even steep inclines. The 4 wheel independent
steering allows the IMAGINE robot to move freely in any direction
without regard to its current rotational orientation. Both a 3-wheel (2
drive + 1 caster) and 4 wheel (2 drive + 2 casters) Akerman steering
system requires the robot to carve turns in order to point it in the
direction it desires to travel. This would make maneuvering difficult in
tight spaces such as a crowded convention floor,or between SP nodes. Our
robot design will be able to spin on it\'s center axis; maintaining a
turn radius close to zero. The robot\'s base will also contain a number
of active proximity sensors (both infrared and ultrasonic) to prevent it
from colliding with people and other obstacles in tight spaces.

You can find engineering diagrams of the wheel design at

<http://teracet.lbl.gov:8080/Private/wheels.html>

### Access Grid Video/Audio

The robot will provide 2-way video and audio conferencing over a
standard 802.11 wireless networking interface. This will be accomplished
using software and hardware that is compatible with the Access Grid
environment ([http://www.accessgrid.org](http://www.accessgrid.org/)).
This will allow us to share the robot\'s audio/video feeds on the Access
Grid as well as take advantage of a number of off-the-shelf hardware and
software components. The Access Grid services are hosted on two on-board
miniature (3"x5") Pentium III PC\'s.
(http://dit.lbl.gov/IMAGINE/Progress.html)

![](media/image1.jpeg){width="3.0in"
height="2.4in"}![](media/image2.jpeg){width="3.0in" height="2.4in"}

### Remote Control

Since the robot\'s audio and video conferencing subsystem is implemented
using Access-Grid technologies, mobility can be controlled through the
same Internet connection used to carry the audio and video feeds. We
will typically use the Access Grid in 50B LBNL to remotely access and
control the robot. Once deployed, any AGnode can be used. The
video/audio feeds from our robot can be shared with everyone on the
Access Grid and will become an integral part of that collaborative
medium. Integration of drive and a/v control is realized through the
LBNL DevServ software infrastructure. This ser­vice has already proved
successful for the remote control of video cameras on other Agnodes. As
an added security feature, the control of the robot will be fully
encrypted to prevent hackers from hijacking control of the robot.

An initial (debug) GUI design has been posted at

<http://teracet.lbl.gov:8080/Private/debug_gui.html>

This will eventually lead to more functional GUIs with integrated motion
maps such as the one at

<http://teracet.lbl.gov:8080/Private/robot_gui.html>

# Long Term Support

The robot is being constructed as much as possible from off-the-shelf
integrated components. This ensures the long-term maintainability of the
platform due to ease of part replacement from well-established
manufacturers. Those components that are constructed in-house (like the
wheel assemblies) are in many ways over-engineered in order to ensure
that they outlast any other component on the platform. The IMAGINE robot
development team is carefully documenting all components and
interactions between components on the robot platform in order to ensure
that the robot can be repaired over the long term if the original
development team is not available. Members of the team will be available
for consultation in the event that the robot breaks and needs repair.

There are many additional options for long term maintenance, but we
would like to defer discussion of these options until the first
prototype is completed. We need to have some experience operating and
testing the prototype before we can evaluate our final plan for
long-term maintenance and repair options.

# Cost of Components

Following is a simplified outline of the major component costs involved
in constructing the robot. For a comprehensive itemized list of
components and suppliers, please refer to Appendix A. The list of
components involved in construction of the motion platform (the robot
motion and drive electronics) has been separated from the components
used for the video-conferencing and remote control (the Access Grid
compatible set of PC's and A/V peripherals).

+-----------------------------------------------------------------------+
| ## Motion Platform Costs                                              |
+-----------------------------------------------------------------------+
| +---+----------------------------------------------------+-------+    |
| | # | #### Description                                   | ####  |    |
| | # |                                                    |  Cost |    |
| | # |                                                    |       |    |
| | # |                                                    |       |    |
| |   |                                                    |       |    |
| | Q |                                                    |       |    |
| | t |                                                    |       |    |
| | y |                                                    |       |    |
| +---+----------------------------------------------------+-------+    |
| | 8 | Electric motors (4 for steering and 4 for drive)   | \$1   |    |
| |   |                                                    | 80/ea |    |
| +---+----------------------------------------------------+-------+    |
| | 2 | 12V sealed lead-acid batteries                     | \$1   |    |
| |   |                                                    | 00/ea |    |
| +---+----------------------------------------------------+-------+    |
| | 1 | Battery Charger                                    | \$1   |    |
| |   |                                                    | 20/ea |    |
| +---+----------------------------------------------------+-------+    |
| | 8 | Motor Speed Controllers                            | \$1   |    |
| |   |                                                    | 10/ea |    |
| +---+----------------------------------------------------+-------+    |
| | 1 | Mini Serial Servo Controller (controls 8 motors)   | \$    |    |
| |   |                                                    | 49/ea |    |
| +---+----------------------------------------------------+-------+    |
| | 2 | Incremental encoder-to-serial bus adaptor          | \$1   |    |
| |   |                                                    | 95/ea |    |
| |   | *used to interface to motor position sensors       |       |    |
| |   | (incremental encoders)*                            |       |    |
| +---+----------------------------------------------------+-------+    |
| | 3 | Basic Stamp 2SX Microcontrollers + Carrier board   | \$1   |    |
| |   |                                                    | 00/ea |    |
| +---+----------------------------------------------------+-------+    |
| | N | Various proximity sensors (IR and Ultrasonic)      | \$60  |    |
| | a |                                                    |       |    |
| | . |                                                    |       |    |
| +---+----------------------------------------------------+-------+    |
| | N | Bearings Washers and other mechanical components   | \$500 |    |
| | a |                                                    |       |    |
| | . |                                                    |       |    |
| +---+----------------------------------------------------+-------+    |
+-----------------------------------------------------------------------+
| #### Anticipated Cost for Robot Motion Platform=\$3940                |
+-----------------------------------------------------------------------+

+-----------------------------------------------------------------------+
| ## Access Grid Node Costs                                             |
+-----------------------------------------------------------------------+
| +---+----------------------------------------------------+--------+   |
| | # | #### Description                                   | ###    |   |
| | # |                                                    | # Cost |   |
| | # |                                                    |        |   |
| | # |                                                    |        |   |
| |   |                                                    |        |   |
| | Q |                                                    |        |   |
| | t |                                                    |        |   |
| | y |                                                    |        |   |
| +---+----------------------------------------------------+--------+   |
| | 2 | 500MHz Pentium III miniature PC's with 256Megs     | \$2,   |   |
| |   | RAM, 3 PCI slots, and IBM Microdrive               | 100/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 2 | DC-to-DC ATX PC Power Supplies                     | \$     |   |
| |   |                                                    | 175/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 2 | Hauppauge WinTV Video Capture PCI Cards            | \      |   |
| |   |                                                    | $77/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 1 | Soundblaster Audio Capture PCI Card                | \      |   |
| |   |                                                    | $60/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 2 | PCMCIA to PCI adaptor for 802.11 wireless          | \      |   |
| |   |                                                    | $80/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 2 | PCMCIA 802.11 wireless networking cards            | \$     |   |
| |   |                                                    | 150/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 1 | 8.4" LCD Display                                   | \$     |   |
| |   |                                                    | 475/ea |   |
| +---+----------------------------------------------------+--------+   |
| | 1 | Canon VC-C4R video camera with 10x zoom and        | \$1,   |   |
| |   | motorized orientation control                      | 200/ea |   |
| +---+----------------------------------------------------+--------+   |
| | N | Various (microphones, speakers and cables)         | \$200  |   |
| | a |                                                    |        |   |
| | . |                                                    |        |   |
| +---+----------------------------------------------------+--------+   |
+-----------------------------------------------------------------------+
| #### Anticipated Cost Per Mobile Access Grid Node=\$7,099             |
+-----------------------------------------------------------------------+

# Timelines for Construction

### Overview

We will construct a prototype robot, which is intended to rove on the
show floor of the Supercomputing 2001 convention (SC-Global) in Denver
Colorado. We will be able to demonstrate the initial prototype by
end-July. If the design is acceptable, then we will construct a second
robot for use in the Oakland HPC facility. During SC2001, both the
Oakland and the show-floor robots will participate in the Access Grid
events, which are the central focus of this show and will be a
centerpiece for LBNL/NERSC show floor exhibit. After SC2001, the second
robot can either be a hot-spare/parts source for the Oakland Robot or
remain in service for meetings at LBNL and for future Supercomputing
conferences.

### Robot Base

Currently: Completing construction on first motorized wheel

June 1: First wheel assembly complete and assembled.

June 12: Completed assembly of testing platform. Initial testing using
single drive wheel and 2 casters.

June 19: Testing of drive logic/components using serial-cable tethers
(no wireless yet)

June 26: Construct and assemble 3 more drive wheels.

July 10: Testing with platform incorporating all 4 drive wheels and
Basic Stamp logic/motion-control/steering using wireless DevServ
interface through PC\'s

July 17: Construct "mast" assembly and mount camera+LCD panel on mast.

July 24: Testing using DevServ-based motion controls

### Control Software

Currently: DevServ is up-and-running on the embedded PC's

June 13: Debug GUI interface can speak securely to DevServ.

June 27: DevServ can speak to the Basic Stamp on the 1-wheel testing
assembly. The Debug GUI will be used to drive the single-wheel platform
for testing.

July 11: DevServ interface controls a Canon video camera as well as
switching between 2 microcameras on a second WinTV card on the video
capture PC.

July 18: Debug GUI used for testing the 4-wheel robot base and Cameras.

July 25: A more ergonomic advanced motion control GUI will be tested.

### AccessGrid

June 15: Connect PC with battery power supply and test.

June 22: Bring up PCMCIA/802.11 wireless network interface and bring up
second AG PC.

June 27: Testing of routing video/audio network traffic through
Multicast Bridge (MBR)

July 6: Construct more rugged Lexan cases for mounting the AGnode PC\'s
securely on the robot base (4-wheel platform).

June 11: Testing of remote launching of Access Grid components (ie.
Using a remote Win2k PC to launch the audio/video capture and devserv on
the robot PC\'s.

July 20: Further testing/debugging of audio/video platform and LCD.

July 27: Final testing & debug.

This timeline should bring us to a fully functional prototype on July
30^th^.

**[Appendix A:]{.underline}** *Itemized Component Costs (double click on
object to get full table)*

![](media/image3.wmf)

###