Explorer is an autonomous mobile robot. It is programmed to randomly move, turn and sleep. The robot has a mechanical bumper sensor that detects obstacles (left/right/front). Chassis: Aluminium plate and steel rods. Wheels: 2 + 1 caster wheel. Micro controller: Basic Stamp II. Motors: 2 modified Hitec HS-422 servos. Sensor: Micro switch bumper. Power supply: 6V and 9V Ni-Cad Rechargeable Batteries. Design Philosophy: Avoid constructions that demand critical alignments and use non-permanent attachments. The robot took several months to design and a few weeks to build. I used 3D software to visualise a lot of different ideas. The key design was a circular base so it could turn on the spot. I found out that threaded rods could be used as a solution to many mechanical problems. It was used to attach the servos, batteries and circuit boards. The bumper sensor has been the most difficult problem to solve so far. I experimented with a lot of different types, but I finally settled with an aluminium plate and micro switches. Estimated cost: $150 For more details and pictures & see my site: http://home.swipnet.se/~w-41028/robot/explorer.htm /Tommy Renglin Email: tommy.renglin@swipnet.se