COMPLETED! My 'BUMPY' robot just got completed and it works just great. It had to undergo some major modifications before it started 'bumping' around. To begin with, I tried to use home made geared motors but they turned out to be very noisy. Then I tried to use them directly and ended up spinning the robot round-n-round at the same place. After I overcame this problem I had to face another one. The motors were too noisy (this time in the electromagnetic sense). I thought that the antennas of the bump switch were catching the noise so I decided to insulate them and reduce their size but neither of them worked. At last out of utter frustration I disassembled the body and began building a new one (after a long goodnight sleep). This time everything just turned out to be perfect! (Sometimes a sleep is all you need) This robot building experience has been a very good teacher. So no matter how easy a robot design may be, you always learn something new and useful and that's all that matters. GO AHEAD CREATE YOUR OWN ROBOT!