Trossen Robotics just completed their latest project contest, the Xr-B3 didn’t win but it is a very cool creation!

"He is powered by an AVR ATMEGA324P micro controller on a custom board that I made. He is using an XBEE module to communicate with my PC (and eventually with other robots). Onboard sensory includes: 2 Sharp IR sensors (for wall following and obstacle detection), an SRF-05 sonar sensor and AVRcam. The sonar and camera are mounted in a 2-axis head. He also has quadrature encoders on each wheel, I currently have code implemented for closed loop turns and rolling forward a set distance, but have yet to do continuous speed control. Currently, he still doesn’t do that much. This is intended to be my map-making test platform. He currently does have an onboard planner that, when given an a priori topological map of an area, can navigate the area. I’m still working out the bugs in his ability to actually build the topological map of an area."