Telescoping cylindrical piezoelectric fiber composite actuator assemblies

• US 7,732,998 B2
• Filed: 08/03/2006
• Issued: 06/08/2010
• Est. Priority Date: 08/03/2006
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Allison, Sidney G., Fox Chattin, legal representative, Fox, legal representative, Fox, Robert L., Shams, Qamar A.
• Primary Examiner(s): SAN MARTIN, JAYDI A
• Application Number:
  US11/462,114
• Publication Number:
  US 20100118405A1
• Time in Patent Office: 1,405 Days
• Field of Search: 310/358, 310367-369
• US Class Current: 310/369
• CPC Class Codes: G02B 6/022 using mechanical stress, e.g. tuning by compression or elongation, special geometrical shapes such as "dog-bone" or taper G02B6/02204 takes precedence; optical modulation using photo-elastic effect G02F1/0131
• CPC Class Codes: H02N 2/02 producing linear motion, e.g. actuators; Linear positioners ; Linear motors
• CPC Class Codes: H10N 30/1061 based on piezoelectric or electrostrictive fibres
• CPC Class Codes: H10N 30/506 of cylindrical shape with stacking in radial direction, e.g. coaxial or spiral type rolls

Abstract

A telescoping actuator assembly includes a plurality of cylindrical actuators in a concentric arrangement. Each cylindrical actuator is at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to the concentric arrangement'"'"'s longitudinal axis. Each cylindrical actuator is coupled to concentrically-adjacent ones of the cylindrical actuators such that the plurality of cylindrical actuators can experience telescopic movement. An electrical energy source coupled to the cylindrical actuators applies actuation energy thereto to generate the telescopic movement.

Claims

1. A telescoping actuator assembly, comprising:

a plurality of cylindrical actuators in a concentric arrangement and defining a common longitudinal axis, each of said cylindrical actuators being at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to said common longitudinal axis, each of said cylindrical actuators coupled to concentrically-adjacent ones of said cylindrical actuators such that said plurality of cylindrical actuators can experience telescopic movement along said common longitudinal axis; and

an electrical energy source coupled to said plurality of cylindrical actuators for applying actuation energy thereto to generate said telescopic movement.

2. A telescoping actuator assembly as in claim 1, further comprising:

a first cap fixedly coupled to an end of an innermost one of said plurality of cylindrical actuators;

a second cap fixedly coupled to an end of an outermost one of said plurality of cylindrical actuators, said first cap and said second cap being disposed at opposing ends of said concentric arrangement; and

a strainable element fixedly coupled to each of said first cap and said second cap, and passing longitudinally through said innermost one of said plurality of cylindrical actuators.

3. A telescoping actuator assembly as in claim 2, wherein said strainable element comprises an optical fiber.

4. A telescoping actuator assembly as in claim 2, wherein said strainable element comprises an optical fiber incorporating at least one optical element that can be tuned using mechanical strain.

5. A telescoping actuator assembly as in claim 2, wherein said strainable element comprises an optical fiber incorporating at least one Bragg grating.

6. A telescoping actuator assembly, comprising:

a plurality of cylindrical actuators in a concentric arrangement and defining a common longitudinal axis, each of said cylindrical actuators being at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to said common longitudinal axis, each of said cylindrical actuators coupled to an adjacent one of said cylindrical actuators disposed therein and coupled to an adjacent one of said cylindrical actuators disposed thereabout; and

an electrical energy source coupled to said plurality of cylindrical actuators for independently applying actuation energy thereto to generate telescopic movement of said cylindrical actuators along said common longitudinal axis.

7. A telescoping actuator assembly as in claim 6, further comprising:

a first cap fixedly coupled to an end of an innermost one of said plurality of cylindrical actuators;

a second cap fixedly coupled to an end of an outermost one of said plurality of cylindrical actuators, said first cap and said second cap being disposed at opposing ends of said concentric arrangement; and

a strainable element fixedly coupled to each of said first cap and said second cap, and passing longitudinally through said innermost one of said plurality of cylindrical actuators.

8. A telescoping actuator assembly as in claim 7, wherein said strainable element comprises an optical fiber.

9. A telescoping actuator assembly as in claim 7, wherein said strainable element comprises an optical fiber incorporating at least one optical element that can be tuned using mechanical strain.

10. A telescoping actuator assembly as in claim 7, wherein said strainable element comprises an optical fiber incorporating at least one Bragg grating.

11. A telescoping actuator assembly, comprising:

a plurality of cylindrical actuators in a concentric arrangement and defining a common longitudinal axis, each of said cylindrical actuators being at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to said common longitudinal axis, each of said cylindrical actuators coupled to an adjacent one of said cylindrical actuators disposed therein and coupled to an adjacent one of said cylindrical actuators disposed thereabout; and

an electrical energy source coupled to said plurality of cylindrical actuators for applying actuation energy thereto in an alternating polarity fashion throughout said concentric arrangement to generate telescopic movement of said cylindrical actuators along said common longitudinal axis.

12. A telescoping actuator assembly as in claim 11, further comprising:

a first cap fixedly coupled to an end of an innermost one of said plurality of cylindrical actuators;

a second cap fixedly coupled to an end of an outermost one of said plurality of cylindrical actuators, said first cap and said second cap being disposed at opposing ends of said concentric arrangement; and

a strainable element fixedly coupled to each of said first cap and said second cap, and passing longitudinally through said innermost one of said plurality of cylindrical actuators.

13. A telescoping actuator assembly as in claim 12, wherein said strainable element comprises an optical fiber.

14. A telescoping actuator assembly as in claim 12, wherein said strainable element comprises an optical fiber incorporating at least one optical element that can be tuned using mechanical strain.

15. A telescoping actuator assembly as in claim 12, wherein said strainable element comprises an optical fiber incorporating at least one Bragg grating.