초록 ▼

Disclosed herein is a programmable shim 28 for positioning a work piece 12 comprising a first plate 30; an optional reference frame 32; and an actuator 34 in operative communication with the first plate 30 and the reference frame 32. Disclosed herein too is a method of aligning a work piece 12 compr

Disclosed herein is a programmable shim 28 for positioning a work piece 12 comprising a first plate 30; an optional reference frame 32; and an actuator 34 in operative communication with the first plate 30 and the reference frame 32. Disclosed herein too is a method of aligning a work piece 12 comprising disposing the work piece 12 upon a first plate 30 of a programmable shim 28; activating an actuator 34 with an external stimulus; wherein the actuator 34 is in operative communication with the first plate 30; and displacing the work piece 12.

대표청구항 ▼

What is claimed is: 1. 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 wher

What is claimed is: 1. 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. 2. The shim of claim 1, wherein the first active material has the ability to return to an original defined shape upon application of an external stimulus. 3. The shim of claim 1, wherein the first active material undergoes a change in at least one of stiffness and shape in proportion to the strength of an external stimulus. 4. The shim of claim 1, wherein the reference frame partially or completely surrounds the first plate and wherein the first plate upon actuation by the actuator can be displaced vertically, horizontally and/or rotationally with respect to the reference frame. 5. The shim of claim 1, wherein the first active material can change at least one of its shear strength, modulus properties, and shape to control the position of the first plate with respect to the reference frame. 6. The shim of claim 1, wherein the actuator employs control logic and/or a feedback loop to adjust the position of the shim; wherein the workpiece generates a force pattern reflecting the position of the workpiece; and wherein the shim is in operative communication with a sensor that detects the force pattern of the workpiece, to allow the shim to adjust the position of the workpiece. 7. The shim of claim 1, wherein the actuator comprises an electric stepper motor, an inchworm, a piezoelectric inchworm, an ultrasonic motor, an electrohydrostatic actuator, a nanomotion piezoelectric motor, a compact hybrid actuator device, or combinations thereof. 8. The shim of claim 7, wherein the electric stepper motor, the inchworm, a piezoelectric inchworm, the ultrasonic motor, the electrohydrostatic actuator, a nanomotion piezoelectric motor, and the compact hybrid actuator device comprise an active material. 9. The shim of claim 1, further comprising a second plate and/or a third plate, wherein the second and/or third plates are in operative communication with the actuator. 10. The shim of claim 9, wherein the second plate and/or the third plate are adopted to act cooperatively and synchronously with a first plate. 11. A method of aligning a work piece comprising: disposing the work piece upon a first plate of a shim; activating a first active material within an actuator with an external stimulus; wherein the actuator is in operative communication with the first plate to displace the work piece; 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 work piece is displaceable vertically, horizontally, and rotationally with respect to a reference frame into a set position; holding said work piece in said set position with a second active material, the second active material being different from the first active material; wherein said shim is configured to position a load of about 0.5 kilograms to 10,000 kilograms; 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. 12. The method of claim 11, further comprising holding the work piece in a displaced position without the assistance of power. 13. The method of claim 11, wherein the work piece is reversibly displaced with respect to a reference frame. 14. The method of claim 11, wherein the actuating comprises applying an external stimulus to the actuator, and wherein the external stimulus is thermal, electric, magnetic, radiation, chemical, or a combination comprising at least one of the foregoing external stimuli. 15. The method of claim 11, wherein the shim displaces the work piece to a distance of less than or equal to about 50 micrometers from a specified reference point. 16. The shim of claim 1, wherein the actuator further comprises: a shell at least partially surrounding the second active material, the second active material in a longitudinal bundle that is affixed to an inner surface of the shell, and the first active material in a matrix surrounding the shell and the second active material; wherein an external stimulus to the first active material deforms the shell and displaces the first plate from an original position into the set position; wherein the second active material is configured to be heated while the set position of the first plate is established by the external stimulus to the first active material; and wherein the second active material is configured to be cooled to hold the first plate in the set position once established. 17. The shim of claim 16, wherein: the first active material is a shape memory alloy; and the second active material is a shape memory polymer. 18. The shim of claim 16, further comprising a structural member in contact with the shell and the second active material, configured to control the stiffness distribution of the shim. 19. The shim of claim 1, further comprising: a piston in contact with the first plate and the first active material; a brake lining engageable between the piston and the reference frame, that prevents the movement of the first plate when the brake lining is engaged; wherein the first active material is a paraffin-based material that expands on heating to disengage the brake lining from the piston and displace the first plate from an original position into the set position; wherein the paraffin-based material is configured to be cooled once the set position is reached, thereby engaging the brake lining to hold the first plate in the set position; and an elastic element to restore the first plate to the original position when the brake lining is disengaged. 20. The shim of claim 19, further comprising at least one supplementary actuator configured to disengage the brake lining from the piston by deforming at least one wall of the reference frame; and wherein the supplementary actuator disengages the brake lining without heating the paraffin-based material. 21. The shim of claim 1, further comprising: a main piston in contact with the first plate and the first active material; a second active material in contact with the first plate and at least one side piston; wherein the first active material is a paraffin-based material that expands on heating to displace the first plate from an original position into the set position, wherein the paraffin-based material is cooled once the set position is reached; wherein the second active material can be activated in response to a first external stimulus to hold the first plate in the set position with respect to the reference frame; wherein the second active material can be un-activated in response to a second external stimulus to allow the movement of the first plate with respect to the reference frame; an elastic element to restore the first plate to the original position when the second active material is un-activated; and wherein the reference frame at least partially surrounds the main piston and the side piston. 22. The shim of claim 21, wherein: the second active material is a magnetorheological fluid; and the second active material is activated and un-activated through a change in at least one of its shear strength, modulus properties, and shape. 23. The shim of claim 21, wherein: the second active material is an electrorheological fluid; and the second active material is activated and un-activated through a change in at least one of its shear strength, modulus properties, and shape.