Abstract: An energy harvester apparatus that includes a piezoelectric beam having opposing first and second ends, with the first end being fixedly supported to a support structure. A negative spring force subsystem has a first end fixedly secured against movement, and a second end secured to the second end of said piezoelectric beam. The negative spring force subsystem includes a linkage system and a biasing element operably associated with the linkage system for applying an adjustable, negative spring force to the piezoelectric beam to soften the piezoelectric beam. The negative spring force subsystem is adjusted to flex the beam sufficiently to overcome the inherent stiffness of the beam such that two stable positions for the beam are created. The beam is therefore able to oscillate between the two stable positions in an over center fashion in response to a low magnitude vibration signal. In various embodiments the system is implemented to provide an input drive signal to control various types of external devices.

Abstract: A non-linear power generator system that may include a flexible beam for receiving a mechanical input, the flexible beam being supported in a bowed configuration; an electrically responsive member supported adjacent one end of the flexible beam so as to be under a compressive force exerted by the flexible beam; and the flexible beam being adapted to move towards a flattened shape from the bowed shape in response to the mechanical input, to transmit the mechanical input to the electrically responsive member, to cause a compression of the electrically responsive member that results in an electrical output signal being generated by the electrically responsive member.

Abstract: An energy harvester apparatus that includes a piezoelectric beam having opposing first and second ends, with the first end being fixedly supported to a support structure. A negative spring force subsystem has a first end fixedly secured against movement, and a second end secured to the second end of said piezoelectric beam. The negative spring force subsystem includes a linkage system and a biasing element operably associated with the linkage system for applying an adjustable, negative spring force to the piezoelectric beam to soften the piezoelectric beam. The negative spring force subsystem is adjusted to flex the beam sufficiently to overcome the inherent stiffness of the beam such that two stable positions for the beam are created. The beam is therefore able to oscillate between the two stable positions in an over center fashion in response to a low magnitude vibration signal. In various embodiments the system is implemented to provide an input drive signal to control various types of external devices.

Abstract: A non-linear power generator system that may include a flexible beam for receiving a mechanical input, the flexible beam being supported in a bowed configuration; an electrically responsive member supported adjacent one end of the flexible beam so as to be under a compressive force exerted by the flexible beam; and the flexible beam being adapted to move towards a flattened shape from the bowed shape in response to the mechanical input, to transmit the mechanical input to the electrically responsive member, to cause a compression of the electrically responsive member that results in an electrical output signal being generated by the electrically responsive member.

Abstract: A non-linear, piezoelectric mechanical-to-electrical generator especially well adapted for use with a Stirling engine, to thus form an electrical power generation system. In one form the generator includes a flexible beam that is configured in a bowed orientation to exert a compressive stress on a piezoceramic stack. A mechanical, linearly reciprocating member is positioned against the flexible beam at a midpoint of the beam. The mechanical member applies a force to the flexible beam that initially tends to flatten the flexible beam, which increases the compressive stress applied to the piezoceramic stack, thus compressing the stack and causing it to generate an electrical output signal. When the mechanical member removes the force, the flexible beam reverts to its initial, bowed configuration. This allows the piezoceramic stack to decompress, and it generates another electrical signal.

Abstract: A non-linear, piezoelectric mechanical-to-electrical generator especially well adapted for use with a Stirling engine, to thus form an electrical power generation system. In one form the generator includes a flexible beam that is configured in a bowed orientation to exert a compressive stress on a piezoceramic stack. A mechanical, linearly reciprocating member is positioned against the flexible beam at a midpoint of the beam. The mechanical member applies a force to the flexible beam that initially tends to flatten the flexible beam, which increases the compressive stress applied to the piezoceramic stack, thus compressing the stack and causing it to generate an electrical output signal. When the mechanical member removes the force, the flexible beam reverts to its initial, bowed configuration. This allows the piezoceramic stack to decompress, and it generates another electrical signal.

Abstract: The present invention presents a system for a compound actuator. The system includes first and second electrode layers each including two electrode sections, an intermediate electrode layer between the first and second electrode layers, and first and second electrostrictive materials that change length in an applied electrical field. The first electrostrictive material is positioned between the first and intermediate electrode layers. The second electrostrictive material is positioned between the intermediate and second electrode layers. The first electrostrictive material has a first length adjoining the first electrode section and a second length adjoining the second electrode section. The second electrostrictive material has a third length adjoining the fourth electrode section and a fourth length adjoining the fifth electrode section.

Abstract: The present invention presents a system for a compound actuator. The system includes first and second electrode layers each including two electrode sections, an intermediate electrode layer between the first and second electrode layers, and first and second electrostrictive materials that change length in an applied electrical field. The first electrostrictive material is positioned between the first and intermediate electrode layers. The second electrostrictive material is positioned between the intermediate and second electrode layers. The first electrostrictive material has a first length adjoining the first electrode section and a second length adjoining the second electrode section. The second electrostrictive material has a third length adjoining the fourth electrode section and a fourth length adjoining the fifth electrode section.

Abstract: A bimorph actuator is driven by electrostrictive materials configured to change length in response to applied electrical field. A first electrostrictive material is positioned between a first electrode and a second electrode. A second electrostrictive material is positioned between a second electrode and a third electrode. The second electrostrictive material and the first electrostrictive material are attached to each other such that a differential change in their respective lengths results in a lateral motion. A first voltage source provides a voltage differential between the first electrode and the third electrode. A second variable voltage applied to the second electrode causes the length of the first electrostrictive material to lengthen when the second electrostrictive material shortens, and vice versa. A system of electrodes for the bimorph actuator and a method for actuating electrostrictive materials are also provided.

Abstract: The present invention presents a system for a compound actuator. The system includes first and second electrode layers each including two electrode sections, an intermediate electrode layer between the first and second electrode layers, and first and second electrostrictive materials that change length in an applied electrical field. The first electrostrictive material is positioned between the first and intermediate electrode layers. The second electrostrictive material is positioned between the intermediate and second electrode layers. The first electrostrictive material has a first length adjoining the first electrode section and a second length adjoining the second electrode section. The second electrostrictive material has a third length adjoining the fourth electrode section and a fourth length adjoining the fifth electrode section.

Abstract: A bimorph actuator is driven by electrostrictive materials configured to change length in response to applied electrical field. A first electrostrictive material is positioned between a first electrode and a second electrode. A second electrostrictive material is positioned between a second electrode and a third electrode. The second electrostrictive material and the first electrostrictive material are attached to each other such that a differential change in their respective lengths results in a lateral motion. A first voltage source provides a voltage differential between the first electrode and the third electrode. A second variable voltage applied to the second electrode causes the length of the first electrostrictive material to lengthen when the second electrostrictive material shortens, and vice versa. A system of electrodes for the bimorph actuator and a method for actuating electrostrictive materials are also provided.