JOIN USJosh Bongard created both simulated and actual robots that, like tadpoles becoming frogs, change their body forms while learning how to walk.
Year after year, his simulated robots also evolved, spending less time in “infant” tadpole-like forms and more time in “adult” four-legged forms, becoming abler than ones with fixed body forms. “This paper shows that body change, morphological change, actually helps us design better robots,” Bongard said.
In some ways, they are too much like people for people to easily understand them, Bongard says.
“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 and the emergent behaviour from the complex system which is a robot, is some useful task like clearing up a construction site or laying pavement for a new road,” Bongard said. Bongard used a computer simulation to release a series of robots that move about in a 3-dimensional space.
“It looks like a modern video game,” he says. Each creature—or, rather, generations of the creatures—then run a software routine, called a genetic algorithm, that experiments with various motions until it develops a slither, shuffle, or walking gait — based on its body plan — that can get it to the light source without tipping over.
“The robots have 12 moving parts. They look like the simplified skeleton of a mammal: it’s got a jointed spine and then you have four sticks—the legs—sticking out,” Bongard said. “The snake and reptilian robots are, in essence, training wheels,” said Bongard, “they allow evolution to find motion patterns quicker, because those kinds of robots can’t fall over.
“So evolution only has to solve the movement problem, but not the balance problem, initially. Then gradually over time it’s able to tackle the balance problem after already solving the movement problem.” In effect, the robots are being “raised” as humans, who are taught how to roll, then crawl and, finally, walk.