While doing research for an article, I bumped into this incredible BEAM robot project. The builder, Bruce Robinson, wanted to know how complex a behavior set he could get from a robot using only BEAM technology (i.e. analog electronics and no microcontroller). The result, Hider, has nine sensor systems! Robinson writes:
“Hider is concerned with survival. Normally it parks itself in bright light where it is easily seen. If the light gets dim, it looks for a brighter place. In the dark it stays still and flashes a beacon every few seconds so it won’t get stepped on. And if it hears a loud noise, such as a door slamming or people talking, it “runs away” and looks for a dark place to hide in.
“While Hider performs more or less as intended, there have been a few surprises. For example, in the photo (below) Hider is “looking” at the darkest thing in a sunlit room — a wooden column. While we might think of a shadow as being darker, Hider doesn’t see it that way; its “eyes” look at the walls, not the floor. In a room with white walls and pale furniture, a nearby column of reddish coloured wood looks very dark.”
Robinson has exhaustive details on Hider’s design, logic, schematics for all the circuits, pictures of the construction, and lots of other info. The schematics are gorgeous, a model for how this sort of thing should be done.
One of the things that’s always frustrated me about BEAM is that, with the exception of Mark Tilden’s work at Wow Wee, few people seem to be experimenting with/applying BEAM principles in building complex (or relatively complex) analog control systems. This is one of the better, and better documented, projects I’ve seen.