The use of active prostheses for the lower extremity is limited by the amount of electric energy stored in batteries. A promising way to extend their usage time is to convert motions generated by the human body during walking to electrical energy. A first functioning prototype was designed to transfer kinetic energy from heel contact and forefoot contact to a generator by using a fluidic system. Experimental results show that walking with the system generates an average electrical power of 0.8 W. The design of the energy scavenging system (ESS) is presented and results are discussed.