When it goes, it goes like this... Forward motion until the feeler touches something which reverses the motor. When it backs up, the motor has a clutch that causes one leg to not move in reverse. The net effect is when the bug backs up, it turns, thus a simple object avoidance algorithm runs without a control computer to make it happen. I almost forgot, there is a clapper in the HexBug. Yeah, just clap and it reverses, whether it hits something or not. I forgot to show that in the video.

I got this one at Radio Shack, but I'll bet you can find one. Based on BEAM robot technology, it's got the smallest motor you can imagine, but it runs great and would supply hours of cubicle escapism.

It`s not that hard to get apart. But getting it back together will stress you a little, best to just line it up and press it in place.

The Wings or other cover depending on your Model, simply pop-off. Try a little pressure on each of the posts the first time. Gently nudge it till it comes off.

Next, armed with jeweler`s screwdrivers remove the screws that hold the body together.

You can clearly see the motor in the lower left of the picture. Note the coolness in the gearbox. Anytime the motor goes into reverse, it opens the transmission so to speak and the legs on one side stop moving while the other legs move as expected...

It`s the little spring mechanism you can see in the photo. That spring makes sure the axle can only turn in one direction, even when the motor is reversed.

I haven`t been into the electronics yet, but it`s probably super-simple...

AnyWay, for around Ten bucks US, it is pretty fun!