Teletraan I

Teletraan I is a robot designed and built for the IGVC competition. Construction on the robot began in the Spring of 2009.

= Platform = This section gives a description of the platform used for the 2009 IGVC competition.

RMP 400
Teletraan I is based on the Segway RMP 400, part of Segway's Robotic Mobility Platform line of products. The RMP 400 consists of two Segway "Powerbases," which have been combined with several sheets of black annodized 1/4" aluminum. Each Segway Powerbase consists of
 * Two batteries
 * Two wheels
 * Two brushless motors and gearboxes (one on each wheel),
 * An IMU system (accelerometers and gyros)
 * Control circuitry with an E-stop, USB port, AC charge port, power buttons, and backup battery.

RMP Modifications
The RMP 400 comes as a bare system, with two powerbases and a simple frame around them. In order to use the RMP 400 for autonomous navigation, many modifications need to be made so sensors and auxiliary systems can be mounted and powered. The platform modifications made to the robot are as follows
 * Pull-out front and rear drawers, with wire management.
 * Center-mounted Lead Acid Battery Tray
 * Flip-open upper lid
 * Sensor and Computer tower with GPS/Camera mast
 * Front mounted headlights

Sensors
This robot is equipped with several sensors in order to compete in the IGVC competition. These include
 * SICK LMS-200 Scanning Laser Rangefinder
 * Hemisphere A100 GPS receiver
 * OceanServer OS5000 digital compass
 * UniBrain Fire-I Firewire Digital Camera
 * 3 Hokuyo URG-04LX Scanning Laser Rangefinders
 * PowerCube Pan/Tilt Module

Power System
This robot essentially contains two separate power systems. Both Powerbases contain two 72 volt Lithium Polymer batteries, which provide power to the Powerbase systems (motors, IMU, control circuits). Accessing the power stored in these batteries is not easy, and would probably void the warranty. Two 55Ah 12v Lead Acid batteries were installed into the center of the robot. These batteries are combined in series to produce 24 volts of power necessary to drive the SICK laser and PowerCube. There is a 24v to 5v voltage regulator installed in the front pull-out drawer, which provides power for the Hokuyo lasers, powered USB hubs. Sensors that require 12 volts of power are wired to a single battery, instead of both batteries in series. Each laptop runs off of its own internal battery.

Charging takes place through two means. The rear panel of the RMP 400 has been fitted with a 7 pin Charging Port, providing independent connections to the two 12v batteries and a 110VAC source. The Powerbases and Laptops are charged through the 110VAC source (each laptop has its own standard wall-plug charger onboard). The Lead Acid batteries are charged independently, via an outboard charger. In order to facilitate parallel charging and series operation, a RUN/CHARGE switch was mounted on the rear panel next to the charging port. RUN mode actuates a relay that connects the batteries in series and completes the circuit to the rest of the sensors on board. CHARGE mode toggles the relay the other way, which disconnects the batteries from the on-board systems, and routes them each directly to pins on the charging port.

Computational Power
Teletraan I carried three laptop computers in the IGVC competition. Two of the computers were housed in the rear pull-out drawer, and the third was mounted on top of the sensor tower. The computers were all identical Dell laptops with high capacity batteries, 32gb solid state hard drives, 2.4GHz Intel Core Processors, and 2gb of RAM.

The computers were all networked via 100 megabit Ethernet connections, through an on-board Linksys WRT-150N wireless router running the DD-WRT firmware.

= Namesake = Teletraan I is from the original Transformers animated series. It is the name of the central navigation computer on the "Ark," the ship that took the Autobots to Earth.