Photopopper 4.2 Photovore was bought from Solarbotics. It will avoid obstacles and move toward light source.
I bought SolarSpeeder 1.0 from Solarbotics and spend about 2 hours to put it together. It works pretty well under my table lamp. Please refer to "A Beginner's Experience with BEAM Robotics" for more details. However, the "neck" broke after a while. I savage the capacity and motor and build another solar roller which was shown below.
Author: Teddy, 3 October 2001