Hexapod Robots Walk Faster With Flexible Feet
Posted on June 1, 2020
UC San Diego engineers have developed flexible feet that enable hexapod robots to walk up to 40% faster. The feet are flexible spheres made from a latex membrane filled with coffee grounds.
The researchers explain in a release that the feet enable the robots to walk faster and grip easier because of a mechanism called granular jamming. The coffee grounds behave both like a liquid and a solid inside the membrane. The feet firm up and conform to the ground underneath the robot when they hit the ground and they unjam and loosen up between steps.
The feet were installed on a commercially available hexapod robot. Researchers designed and built an on-board system that can generate negative pressure to control the jamming of the feet, as well as positive pressure to unjam the feet between each step. As a result, the feet can be actively jammed, with a vacuum pump removing air from between the coffee grounds and stiffening the foot. But the feet also can be passively jammed, when the weight of the robot pushes the air out from between the coffee grounds inside, causing them to stiffen.
Michael T. Tolley, a professor in the Department of Mechanical and Aerospace Engineering at UC San Diego and senior author of the paper, says in the announcement, "Usually, robots are only able to control motion at specific joints. In this work, we showed that a robot that can control the stiffness, and hence the shape, of its feet outperforms traditional designs and is able to adapt to a wide variety of terrains."
The researchers will present their findings at the RoboSoft conference. This video shows the robot crossing different terrains with its granular boots.