Controllable motion damping for prosthetic limbs and robotics

The technology offered here provides instant damping control and tunable shock absorption in low-power mechanical systems. The invention is a soft structure which contains magneto-rheological fluid (MRF), which hardens under applied magnetic fields. Unlike existing MRF technologies, which only operate under strong magnetic fields, the invention releases the constrain on controlling field. The field required is only 1/100 of the existing technologies. Hence this invention provides unique damping capability for low-power systems. In addition, the invention is composed of soft materials, which means it can fit into systems of different geometry.


This technology is applicable for controllable motion damping in low-power systems, especially prosthetic limbs and robotics. Active control of motion damping usually requires strong magnetic fields, and thus can only be implemented in high-power systems. A team of Harvard researchers led by Robert Wood invented a new controllable damping mechanism, which operates under low magnetic fields. It provides low-power systems, such as prosthetic limbs and robotics, controllable frictions between surfaces, as well as tunable rigidity and viscosity.

U.S. Patent(s) Issued: US8579842B2