How Knee-joint Movements Can Be Used Generate Electricity?

Have you ever thought of making use of the large change in angle by your knee when you walk? Its amazing to see a team of scientists from the U.K.’s Cranfield University, University of Liverpool and University of Salford working on this technology where a wearable piezoelectric device will convert knee movement into electric current. This energy can further be used to power gadgets such as GPS, heart rate monitors, pedometers and accelerometers.

How does it work?

The device is called as the pizzicato knee-joint energy harvester, which fits on the knee. This is in the form of a ring which rotates about a quarter of a turn with every bend of the knee, causing the plectra (like guitar pick) to pluck the arms. This leads to the vibration of arms, finally generating electric energy.

The device was tested on a knee motion simulator rig using motion capture system on the human gait. The estimated production model may cost less than US$15.57 per unit. Previously, industrial designer Kyle Toole built a prototype device that generated electricity not from the bending of the knee, but from the shock forces that traveled up to it from heel strikes against the ground.