Mapping and localization are the hottest trend in robotics today. And what is the most exciting is they can be both implemented on a low-cost robotics kit like LEGO Mindstorms!
I tried to make a self-driving car, after Google's famous car, but I got stuck on the mechanical side. I can't figure out how to build a revolving ultrasonic sensor on top of the robot, in order to do mapping and localization.
Any help is highly appreciated!