Patent ID: 8669691

Claim:
A method of generating electricity from motion with a micro-scale smart material actuator having an overall length smaller than 10 millimeters, said actuator comprising a unitary mechanical amplifier comprising a fixed supporting member having a first mounting surface, an opposed movable supporting member having a second mounting surface, at least one actuating arm, and a mechanical link connecting said movable supporting member and said actuating arm; and a piezoelectric stack affixed between said first mounting surface and said second mounting surface, wherein said fixed supporting member is substantially rigid and said first mounting surface and said second mounting surface are substantially parallel such that upon application of an electrical potential to said piezoelectric stack, said piezoelectric stack expands substantially without movement of said fixed supporting member and substantially without angular movement of said piezoelectric stack; said mechanical link comprises at least one compliant member linking said movable supporting member and said actuating arm whereby movement of said movable supporting member causes amplified movement of said actuating arm; and said fixed supporting member, said movable supporting member and said mechanical link are adapted such that said piezoelectric stack is compressed by a predetermined amount such that said piezoelectric stack remains compressed when no electric potential is applied and said compressive force is substantially evenly applied to said piezoelectric stack such that upon application of an electric potential, said piezoelectric material expands without significant angular flexing, said method comprising the steps of embedding said actuator in the body of an animal; connecting an electrical load to said piezoelectric stack of said actuator and connecting said actuator arm to a source of mechanical motion whereby said source of motion causes said actuator arm to move, whereby said mechanical link causes said movable supporting member to exert and release pressure on said piezoelectric stack, thereby causing said piezoelectric stack to generate an electric current into said electric load.