Robot Hardware and Software


Autonomous Mobile Robotics at URCS

Description of Robot Hardware

The mobile robotics group at University of Rochester is equipped with two wheelchair based mobile robots bought using DARPA-DURIP funds. The wheelchair platforms are capable of limited operation in off-road situations as well. The wheelchair platform was purchased from KIPR and was developed under KIPR's Tinman robots project. The motors are controlled via an onset M332 microcontroller. The platform also came equipped with 12 infra red proximity sensors, a sonar sensor, motor shaft encoders for odometry, and 2 bump sensors on the front fender. The picture on the right shows the wheelchair platforms when they were first received.

We have modified the wheelchair robots by adding extra processing power, communications equipment and additional sensors for visual navigation and better sensing. In addition to the onset M332 microcontroller, we have added dual Pentium processors running Linux on each wheelchair robot for extra processing power. We are currently in the process of upgrading our Pentium processors to Pentium II processors. For communications between the wheelchair robots, and also the department's computer network, each of the wheelchair robots is equipped with a Proxim RangeLAN2 wireless ethernet device. We are also experimenting with the Aironet ARLAN 640 wireless ethernet device. One of the robots is also equipped with an FM-band wireless TV transmitter for sending images from the wheelchair back to a remote workstation for off-board processing.

Sensory enhancements include finer grade shaft encoders for more precise measurement and a CCD camera and suuporting graphics hardware. Some of the work in progress includes building a more modular structure for the robot, installing a combination of stepper motors and servos for pan-and-tilt motion of the camera and installing the SRI stereo vision module (SVM) for 3D range measurements. The image on the right shows the current placement of various sensors on the wheelchair.

Description of Robot Software

The block diagram on the left shows the architecture of the wheelchair robot controller. The motors on the mobile platform are controlled by the M332 microcontroller. The controller is programmed using the ARC C Development Environment from Newton Research Labs. The Pentium computers use the Linux operating system and run various image processing and other algorithms (most of which have been programmed in C/C++). A serial line connects the microcontroller with the on-board Pentium processors and also the SPARCstations in the Department.

Currently, software for performing the following tasks is installed and running on the wheelchairs.

In addition to the mobile robot wheelchairs, some of our developmental work is being done in simulation. This work will soon be ported over to the wheelchair robots and includes

Up to Main Page

This page is maintained by Amit Singhal.

Last update: 12/11/97.