With “a lot of the first walking robots, [scientists] tried to make them like a table,” he says. Researchers thought that robots should be permanently stable. These early efforts in robotics attempted to program exactly where each foot should fall, calculate all the possibilities ahead of time – but human and other animals don’t work that way. Instead, we are actually in a kind of controlled fall, using our feet to sense how best to regain balance after each step.
So, the students at the Leg Lab tried different tacks. They created a succession of robots ranging from stiff-legged machines that bounced to droids that looked progressively more natural. Boston Dynamics’ first successes jogged on four legs, such as Big Dog, a military project designed to carry heavy loads across rough terrain. Big Dog can negotiate snow, forests, and rocky hills – terrain that might stymie wheeled vehicles.
Until recently, moving over anything but level ground was out of the question for most robots. Perhaps the most famous walking humanoid robot, ASIMO, was introduced as a prototype by Japanese car company Honda in the early 1990s. Even after years of revisions and learning to run, ASIMO can still be pushed over easily, struggles with uneven terrain, and moves with a bent-knee gait that doesn’t look much like normal walking.
Leg Lab alumni have since fanned out to several different universities and corporations. One of them, Jerry Pratt, is a research scientist at the Institute for Human and Machine Cognition in Pensacola, Fla.