Tricky terrain is no problem for this four-legged robot
Researchers have designed a system that enables a low-cost and relatively small legged robot to get around even in the face of obstacles. The robot can climb and descend stairs nearly its height; traverse rocky, slippery, uneven, steep, and varied terrain; walk across gaps; scale rocks and curbs; and even operate in the dark. "Empowering small robots to climb stairs and handle a variety of environments is crucial to developing robots that will be useful in people's homes as well as search and rescue operations," says Deepak Pathak, an assistant professor in the Robotics Institute at Carnegie Mellon University. "This system creates a robust and adaptable robot that could perform many everyday tasks." The team put the robot through its paces, testing it on uneven stairs and hillsides at public parks, challenging it to walk across steppingstones and over slippery surfaces, and asking it to climb stairs that, for its height, would be akin to a human leaping over a hurdle. The robot adapts quickly and masters challenging terrain by relying on its vision and a small onboard computer. The researchers trained the robot with 4,000 clones of it in a simulator, where they practiced walking and climbing on challenging terrain. The simulator's speed allowed the robot to gain six years of experience in a single day. The simulator also stored the motor skills it learned during training in a neural network that the researchers copied to the real robot. This approach did not require any hand-engineering of the robot's movements -- a departure from traditional methods. Most robotic systems use cameras to create a map of the surrounding environment and use that map to plan movements before executing them. The process is slow and can often falter due to inherent fuzziness, inaccuracies, or misperceptions in the mapping stage that affect the subsequent planning and movements.