Robotics: Electrostatic brakes make bendy robot arms a lot more efficient

Replacing motors with electrostatic brakes can boost the energy-efficiency of robot limbs, although the robots are slower

By Matthew Sparkes

Robotic limbs that are controlled by electrostatic brakes rather than many motors could lead to a new generation of lightweight robots that use around 90 per cent less power than existing designs.

Robots usually have one or more motors for every joint to control its movement, but Patrick Lancaster at the University of Washington in Seattle and his colleagues have created simple brakes that enable joints to be frozen or released in precise combinations so that a single motor can power a limb with as many as 10 joints.

Each electrostatic brake is made of two thin sheets of metal …