US Patent 8928161 Apparatuses and methods for harvesting energy from prosthetic limbs

An apparatus for harvesting energy from motion of a prosthetic limb, wherein the prosthetic limb has motion in at least one degree of freedom, may include a hydraulic amplifier mechanically coupled with a generator. The hydraulic amplifier may include an input member configured to receive an input motion when a first motion in a degree of freedom of the prosthetic limb causes pressure and motion of hydraulic fluid. The hydraulic amplifier is configured to amplify the input motion of the input member to a greater output motion. The generator is configured to convert mechanical energy of the output motion into corresponding electrical energy delivered to one of an electrical load and an electrical storage reservoir.