Patent ID: 7202591

Claim:
A system for a compound actuator, the system comprising: a first electrode layer including a first electrode section and a second electrode section; a second electrode layer including a third electrode section, the third electrode section being arranged to overlap the first and second sections; a first electrostrictive material configured to change length in response to an applied electrical field, the first electrostrictive material being positioned between the first electrode layer and the second electrode layer, the first electrostrictive material having a first length adjoining the first electrode section and a second length adjoining the second electrode section; a third electrode layer including a fourth electrode section and a fifth electrode section, the fourth and fifth electrode sections being arranged to overlap the first and second electrode sections, respectively; a second electrostrictive material configured to change length in response to an applied electrical field, the second electrostrictive material being positioned between the second electrode layer and the third electrode layer, the second electrostrictive material having a third length adjoining the fourth electrode section and a fourth length adjoining the fifth electrode section; a first voltage source arranged to provide a voltage differential between the first electrode section and the fourth electrode section, and between the second electrode section and the fifth electrode section, the voltage differential causing the first electrostrictive material and the second electrostrictive material to change from the first length, the second length, the third length and the fourth length to a fifth length, a sixth length, a seventh length, and an eighth length, respectively, that are shorter than the first length, the second length, the third length, and the fourth length, respectively; and a second voltage source arranged to provide a variable voltage to the second electrode layer, the variable voltage causing the first electrostrictive material to change from the fifth length towards a ninth length that is shorter than the fifth length and the sixth length towards a tenth length that is longer than the sixth length when the second electrostrictive material changes from the seventh length towards an eleventh length that is longer than the seventh length and the eighth length towards a twelfth length that is shorter than the eighth length, the variable voltage further causing the first electrostrictive material to change from the fifth length towards a thirteenth length that is longer than the fifth length and the sixth length towards a fourteenth length that is longer than the sixth length when the second electrostrictive material changes from the seventh length towards a fifteenth length that is shorter than the seventh length and the eighth length towards a sixteenth length that is longer than the eighth length.