Want to build a really tough robot? Forget about Terminator. Instead, watch a tadpole turn into a frog.
Or at least that's not too far off from what University of Vermont roboticist Josh Bongard has discovered, as he reports in the January 10 online edition of the Proceedings of the National Academy of Sciences.
In a first-of-its-kind experiment, Bongard created both simulated and actual robots that, like tadpoles becoming frogs, change their body forms while learning how to walk. And, over generations, his simulated robots also evolved, spending less time in "infant" tadpole-like forms and more time in "adult" four-legged forms.
These evolving populations of robots were able to learn to walk more rapidly than ones with fixed body forms. And, in their final form, the changing robots had developed a more robust gait -- better able to deal with, say, being knocked with a stick -- than the ones that had learned to walk using upright legs from the beginning.
"This paper shows that body change, morphological change, actually helps us design better robots," Bongard says. "That's never been attempted before."
Bongard's research, supported by the National Science Foundation, is part of a wider venture called evolutionary robotics. "We have an engineering goal," he says "to produce robots as quickly and consistently as possible." In this experimental case: upright four-legged robots that can move themselves to a light source without falling over.
"But we don't know how to program robots very well," Bongard says, because robots are complex systems. In some ways, they are too much like people for people to easily understand them.
"They have lots of moving parts. And their brains, like our brains, have lots of distributed materials: there's neurons and there's sensors and motors and they're all turning on and off in parallel," Bongard says, "and the emergent behavior from the complex system which is a ro
|Contact: Joshua Brown|
University of Vermont