Patent ID: 7538472

Claim:
A shim for positioning a work piece comprising: a first plate attachable to said workpiece; a reference frame; an actuator in operative communication with the first plate and the reference frame; wherein the actuator is selectively actuated by a first active material and wherein the first active material is at least one of a shape memory alloy, a ferromagnetic shape memory alloy, a shape memory polymer, an electroactive polymer, a piezoelectric material, a magnetostrictive material, an electrorheological fluid, a magnetorheological fluid, a magnetorheological elastomer, or a paraffin-based material; wherein the first plate upon actuation by the actuator is displaceable with respect to the reference frame into a set position; wherein the first plate is held in the set position by the actuator without assistance of power; wherein said shim is configured to position a load of about 0.5 kilograms to 10,000 kilograms; wherein the actuator further comprises a second active material to perform the holding of the first plate in the set position without assistance of power, the second active material being different from the first active material; and wherein the second active material is at least one of a shape memory alloy, a ferromagnetic shape memory alloy, a shape memory polymer, an electroactive polymer, a piezoelectric material, a magnetostrictive material, an electrorheological fluid, a magnetorheological fluid, a magnetorheological elastomer, or a paraffin-based material.