TekBot System Modeling and Simulation

The TekBot is part of the Oregon State University (OSU) platforms for learning concept, created to teach students about analog circuitry, digital logic, and embedded systems – all in the context of robotic system design. This system modeling techniques are using the System Vision simulation environment produced by Mentor Graphics.

Modeling with VHDL-AMS and SPICE models, simultaneously, is a significant benefit in exploring and understanding the interactions of the different hardware devices on the TekBot. In addition to modeling the basic TekBot, additional hardware was modeled that would allow the TekBot to find and sort 5 orange balls and 5 black balls into color coded corners in a 10”X10” arena.

System modeling and simulation can be useful in projects such as this one, particularly when there are non-trivial interactions between subsystems. Co-verification of hardware and software was very beneficial. Finally, modeling of the system context proved to be invaluable for this project.

To enable the TekBot to sort the randomly placed balls in the arena, hardware was needed that would not only meet the power requirements of the battery operated system, but would also allow the TekBot to find and move all of the balls in the arena in a timely fashion. To find the balls quickly, a range finder was mounted on the front of the TekBot to determine the approximate distance to an object. The Daventek SRF-08 ultrasonic range finder was chosen because it was fairly inexpensive and operated on the I2C interface, which is a 2-wire communications protocol supported by the microcontroller used on the TekBot.