Custom-Designed Electric Motors for Super-Efficient Running Robot

This 70-pound "cheetah" robot, designed at MIT, may soon outpace its animal counterparts in running efficiency. In treadmill tests, the researchers found that the robot, which is about the size and weight of an actual cheetah, wastes very little energy as it trots continuously for up to an hour and a half at 5 mph. The key to the robot's streamlined stride are specially designed lightweight electric motors, set into its shoulders, that produce high torque with very little heat wasted. The motors can be programmed to quickly adjust the robot's leg stiffness and damping ratio - or cushioning - in response to outside forces such as a push, or a change in terrain. Mechanical energy from the leg as it impacts the ground recharges the cheetah-bot's battery.