BEAM Robots
BEAM ( Biology, Electronics, Aesthetics, Mechanics ) Robots are non-programmable bots. Their functionality relies on analog circuits such as an oscillator who provides simple functions like walking. The inspiration for these projects was a documentary of Mark Tilden and his insect robots. I was simple amazed by the geniality with which he materialized his knowledge. Because at that time I was teaching electronics, I thought it was appropriate for me and my pupils to look for schematics, build and test this things.
Walker bug
The walker bug relies on two chips: one is the oscillator which ensure the cadence movement and the other drives the two servomotors.
The two servomotors are hacked, which means that it had to be opened, removed the stopper which limits the movement of the motors and canceling the small electronic board in the servomotor. In this case we were interested in the mechanical gear to ensure a slower oscillation.
Photovore
Photovore is a BEAM robot that moves following the light.
By analogy you can think of insects in nature that fly at night around a light source. There are many designs of photovore bots on the internet; some of them are using solar cells, some photoresistors, some photodiodes or phototransistors.