Bipedal robots, in general, are a pretty stilted bunch. Their movements are overarticulated, they wobble, they topple, and when faced with an obstacle -- even one as slight as a slope change -- they often can't overcome it.
But that may soon change. This week, researchers from the Univeristy of Arizona published a paper in the Journal of Neural Engineering that describes the development of a new type of robot legs that mimic the neuromuscular architecture of human walking.
In other words, they created a pair of robot legs that are starting to "think" about walking the same way people do.
In humans, sensory feedback from our environment is constantly being collected by our lower limbs and sent to a network of neurons in the spinal column called a central pattern generator, which uses that information to keep our gait even and steady. That's what lets us walk without having to consciously think about it.
Using human legs as a model, the scientists put sensors at the bottoms of the robot legs' feet that tell them whether they are touching the ground. The scientists also gave internal position sensors to each of the motors that pull on the "muscles" in the legs.
The robot legs adapt naturally to changes in their environment. For example, as the legs hit a slight upslope, they will automatically walk slower and push harder, and if they are going downhill, they will walk a little faster.
"The conventional AI paradigm is just do everything with logic, but that doesn't always work very well," Theresa Klein, an electrical engineer and neuroscientist who co-authored the paper, told the Los Angeles Times. "We are rebuilding the idea of how do we really move and navigate through the world, and you get these results that are much more lifelike."
Klein's research should be able to help in the development of robots that move more the way humans do, but it has other applications too. The legs could be used to do research on the neuroscience of walking, which could especially benefit people with spinal cord injuries that affect their legs.