CkBot is a reconfigurable modular robot that is able to reassemble itself after being kicked apart - the Self-Assembly After Explosion problem. Mark Yim, a professor of mechanical engineering at the University of Pennsylvania Modular Robotics Lab (ModLab), describes the ideas behind CkBot.
"Things fall apart, things break all the time. One of the challenges is, can you have a system that puts itself back together again after its been exploded into lots of pieces?
Each of the modules has magnets and computers in them; each module is a little robot by itself. When they come together, they start to form larger robots that talk to each other via an infrared port.
One of the big issues is, how do you do the coordination? How do a bunch of computers work together to do a single thing so they work together and not fight each other? How can they coordinate their movements so they can do something together a larger unit, like walking?
Take a look at this remarkable video; CkBot is kicked apart by a ruthless human; can the parts come back together and walk as one?
(CkBot cluster reconfigures video)
CkBot can change its manner of locomotion by reconfiguring itself. In the following video, CkBot switches from being a rolling robot to a snake-like robot, to get under an obstacle.
(CkBot cluster changes gait, from rolling to snake-like)
An early science-fictional reference to the idea of a self-assembling robot can be found in The Witches of Karres, a 1966 novel by James Schmitz.
The Sheem Robots were modeled after living animals of various worlds, and the Spider is considered to have been the most perfect of them all. This is the last specimen still in existence. You asked whether I had assembled it recently... Yes, I have. It's a most simple process...
The captain swung the gun up, pointed it at Yango's chest.
"What are you hiding?" he asked.
"Why, the activating mechanism," Yango frowned puzzledly. "I understood you wished to see it assembled. You see, the Sheen Robots assemble themselves when the signal to to it is registered by them."