Smart skin structures

• US 6,564,640 B1
• Filed: 11/28/2000
• Issued: 05/20/2003
• Est. Priority Date: 11/28/2000
• Status: Expired due to Fees

• Current Assignee: Quality Research Development & Consulting, Inc.
• Original Assignee: Quality Research Development & Consulting, Inc.
• Inventors: Allaei, Daryoush
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US09/724,369
• Time in Patent Office: 903 Days
• Field of Search: 735/83, 735/88, 735/89, 735/98, 735/99, 736/00, 736/02, 738/621.1, 738/624.2, 73/110.1, 73/120.7, 745/74, 746/59
• US Class Current: 73/583
• CPC Class Codes: F16F 15/00 Suppression of vibrations in systems damping of non-rotary systems using inertia effect F16F7/10; prevention or isolation of vibrations in machine tools B23Q11/0032; suppression of driveline vibrations in hybrid vehicle transmissions B60W30/20 ; vehicle seat suspension devices B60N2/50; methods or devices for protecting against, or damping of, acoustic waves, e.g. sound G10K11/16; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion vibration absorbing or balancing means for aircraft propellers B64C11/008, for rotorcraft rotors B64C27/001 ; testing static and dynamic balance of machines or structures G01M1/00
• CPC Class Codes: F16F 15/005 using electro- or magnetostrictive actuation means generating of mechanical vibrations operating with electrostriction B06B1/06, with magnetostriction B06B1/08; vehicle suspension arrangements characterised by use of piezoelectric elements B60G17/01941; piezoelectric, electrostrictive and magnetostrictive devices per se H10N30/00
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0066 by exciting or detecting vibration or acceleration vibration testing of structures G01M7/00

Abstract

A smart skin structure has vibration energy managing and steering capabilities. The skin can be used to managing vibrations in the skin or shell of a system, subcomponent, device, or structure. The skin has sensors coupled to the skin to obtain a response to vibrations. Actuators integral with the skin can be selectively activated to apply forces to the skin to confine or redirect vibration energy to one or more predetermined skin regions. The forces applied by the actuators can be controlled to create confinement power flows. Further, the skin actuators can be controlled using spatial derivatives of the vibration forces. The structure can be used in, but is not limited to, watercraft, aircraft, space vehicles, automobiles, marine devices, industrial machinery, machine tools, home appliances, buildings, bridges, and offshore oil platforms.

Claims

1. A skin structure comprising:

a skin;

sensors coupled to the skin to measure vibrations of the skin; and

actuators integral with the skin that are selectively activated to apply forces to the skin to redirect vibration energy to one or more predetermined skin regions.

2. The skin structure of claim 1 wherein the skin structure is embodied in a transportation device.

3. The skin structure of claim 1 wherein the skin structure is embodied in a consumer device.

4. The skin structure of claim 1 wherein the skin structure is embodied manufacturing equipment.

5. The skin structure of claim 1 wherein the actuators comprise piezoelectric rods.

6. The skin structure of claim 1 wherein the sensors comprise piezoelectric rods integrally formed in the skin.

7. The skin structure of claim 1 wherein the sensors are coupled to a processor to detect vibration forces and provide control signals to the actuators.

8. The skin structure of claim 7 wherein the control signals activate the actuators to provide either a straight pattern power flow in the skin, an s-shaped pattern power flow in the skin, or a vortex pattern power flow in the skin.

9. The skin structure of claim 7 wherein the control signals activate the actuators based upon spatial derivatives of the detected vibration forces.

10. The skin structure of claim 1 wherein the skin structure is either flat or curved.

11. The skin structure of claim 1 further comprising a passive damping element coupled to the skin.

12. A skin material comprising:

an outer layer;

sensors integral with the outer layer to measure vibrations of the outer layer; and

actuators integral with the outer layer that are selectively activated to apply forces to the outer layer to redirect vibration energy to one or more predetermined skin regions.

13. The skin material of claim 12 wherein the sensors of the skin material are coupled to a controller to detect vibration forces and provide control signals to the actuators.

14. The skin material of claim 13 wherein the control signals activate the actuators to provide either a straight pattern power flow in the skin, an s-shaped pattern power flow in the skin, or a vortex pattern power flow in the skin to redirect vibration energy to one or more predetermined skin material regions.

15. The skin material of claim 13 wherein the control signals activate the actuators to apply feedback forces applied by the actuators such that the feedback forces are proportional to a spatial derivative of the detected vibration forces of the skin material.

16. The skin material of claim 12 wherein the outer layer is comprised of metal.

17. The skin material of claim 12 wherein the actuators and sensors each comprise piezoelectric devices.

18. The skin material of claim 12 further comprises a passive damping element to dissipate vibrations.

19. A structure having a skin material comprising:

an outer layer;

sensors coupled to the outer layer to measure vibrations in the outer layer;

actuators integral with the outer layer; and

a controller coupled to the sensors to provide control signals to the actuators, wherein the control signals activate the actuators to provide a power flow in the outer layer to redirect vibration energy to one or more predetermined regions of the outer layer.

20. The structure of claim 19 wherein the sensors and actuators comprise piezoelectric devices.

21. The structure of claim 19 wherein the structure is selected from the group comprising watercraft, aircraft, space vehicles, automobiles, marine devices, industrial machinery, machine tools, home appliances, buildings, bridges, and offshore oil platforms.

22. The structure of claim 19 further comprising a passive damping element to dissipate vibrations.

23. A method of controlling vibrations in a skin structure comprising:

detecting vibrations in the skin structure; and

applying feedback forces to actuators integrally formed in the skin to redirect vibration energy by creating an energy power flow pattern in the skin.

24. The method of claim 23 wherein the energy power flow pattern is a straight pattern power flow, an s-shaped pattern power flow, or a vortex pattern power flow.

25. The method of claim 23 wherein the skin structure is embodied in a structure selected from the group comprising watercraft, aircraft, space vehicles, automobiles, marine devices, industrial machinery, machine tools, home appliances, buildings, bridges, and offshore oil platforms.

26. The method of claim 23 wherein the actuators comprise piezoelectric devices.

27. The method of claim 23 further comprises:

generating a power supply voltage using sensors coupled to the skin structure, wherein the sensors generate the power supply voltage in response to vibration energy in the skin structure; and

coupling the power supply voltage to the actuators.

28. A method of controlling vibrations in a skin structure comprising:

detecting vibrations in the skin structure;

applying feedback forces to actuators integrally formed in the skin to redirect vibration energy to one or more predetermined regions of the skin structure; and

dissipating the redirected vibration energy from the one or more predetermined regions of the skin structure using a passive dissipation element.

29. A method of controlling vibrations in a skin structure comprising:

detecting vibrations in the skin structure;

processing the detected vibrations to determine appropriate feedback forces to apply;

comparing the determined feedback forces to historical data;

determining if a defect is present in the skin structure; and

applying the feedback forces to actuators integrally formed in the skin to redirect vibration energy.