CASSY is the final PIC-based robot that Dr. Wright designed. Radio Shack had partnered with Vex Robotics to make the basic parts that compose CASSY readily available. This only lasted for a few years, before Vex Robotics struck out independently. However, this robot can be assembled in several hours and introduces students to many mechanical engineering concepts, such as alignment. Off-the-shelf sensors were chosen to measure yaw rate and wheel rotation. The controller communicates with a host computer via bluetooth.
With the advent of 3D printing, this concept has been supplanted by CASSY – v2 which is designed around the Beaglebone Black. This is a work in progress at this point.