Watch emu-inspired robot legs that use less energy to run
Robotic legs that mimic flightless running birds like emus and use just two motors per leg can run more efficiently than more complex devices’
Robotic legs with an unconventional design inspired by emus can run 300 per cent more efficiently than the same device would if designed traditionally. The technology could be used in prosthetics and exoskeletons, say its inventors.
Alexander Badri-Spröwitz at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany, and his colleagues have done away with the usual approach where every joint in a robotic limb has one actuator to open it and one to contract it. Instead, their BirdBot uses just two motors in each 3D-printed leg and long artificial tendons that cover more than one joint, mimicking the anatomy of certain birds that have lost the ability to fly and instead evolved to run efficiently along the ground.
“We’re using just two actuators, one to move the leg back and forward, and one to lift it. Just the bare minimum required,” says Badri-Spröwitz. “Usually in robotics, you’re looking to improve efficiency by just 10 per cent or so, but we’re seeing a 300 per cent increase.”
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The motors pull the tendons. Power is stored in a spring during compression and released when each foot strikes the floor, to help drive the robot forward.