Method and apparatus for inhibiting formation of and/or removing ice from aircraft components

• US 9,821,915 B2
• Filed: 03/21/2016
• Issued: 11/21/2017
• Est. Priority Date: 08/05/2011
• Status: Active Grant

• Current Assignee: General Atomics, Inc.
• Original Assignee: General Atomics, Inc.
• Inventors: Giles, Alan M., Machin, James T., Geriguis, John A.
• Primary Examiner(s): O'Hara, Brian M
• Application Number:
  US15/076,598
• Publication Number:
  US 20160280379A1
• Time in Patent Office: 610 Days
• CPC Class Codes: B64C 11/16 Blades
• CPC Class Codes: B64C 3/00 Wings ornithopter wings B64C33/02
• CPC Class Codes: B64C 9/00 Adjustable control surfaces or members, e.g. rudders trimming stabilising surfaces B64C5/10
• CPC Class Codes: B64D 15/16 by mechanical means
• CPC Class Codes: B64D 15/163 using electro-impulsive devices
• CPC Class Codes: B64D 15/20 Means for detecting icing or initiating de-icing
• CPC Class Codes: B64D 15/22 Automatic initiation by icing detector

Abstract

Methods and systems are generally described that inhibit debris (such as ice) accretions and/or remove debris (such as ice) accretions from the exterior surface of an aircraft. In some embodiments, the invention is a system for an aircraft comprising: a component of the aircraft having a surface; a plurality of piezo-kinetic actuators each positioned proximate to a portion of the surface; and a control unit coupled to the plurality of actuators, the control unit configured to actuate one or more of the actuators at one or more frequencies; wherein the actuators are each configured to introduce a displacement of the surface in three dimensions to inhibit a formation of ice on at least the portion of the surface and to break up existing ice formations on at least the portion of the surface.

Claims

1. A system for an aircraft comprising:

a component of the aircraft having an inner facing surface and an outer facing surface;

a plurality of actuators each positioned proximate to and coupled to the inner facing surface, the plurality of actuators coupled at locations of the inner facing surface directly opposing corresponding locations of the outer facing surface, wherein each of the plurality of actuators comprises a solid-state electric actuator; and

a control unit coupled to the plurality of actuators, the control unit configured to drive one or more of the plurality of actuators at one or more frequencies;

wherein the plurality of actuators are each configured to introduce a displacement of the outer facing surface in three dimensions to perform one or both of inhibiting a formation of ice on at least the corresponding locations of the outer facing surface and breaking up existing ice formations on at least the corresponding locations of the outer facing surface;

wherein the plurality of actuators are flexible and substantially conform to a curvature of the locations of the inner facing surface.

2. The system of claim 1 wherein the control unit comprises:

a microcontroller; and

at least one amplifier coupled to the microcontroller and the plurality of actuators.

3. The system of claim 1 wherein the control unit is configured to have a weight to power output ratio that is less than 0.0125 lbs per watt.

4. The system of claim 1 wherein the component comprises a wing of the aircraft and the outer facing surface comprises an edge surface of the wing that first contacts air during flight.

5. The system of claim 1 wherein the control unit is configured to drive the one or more of the plurality of actuators at one or more frequencies between 55 Hz and 235 Hz.

6. The system of claim 1 wherein the one or more frequencies are one or more predetermined frequencies substantially corresponding to one or more resonant frequencies of the surface, the resonant frequencies at least a function of a geometry of the outer facing surface.

7. The system of claim 1 wherein the control unit is configured to provide power and the one or more of the plurality of actuators are configured to use the power at no more than 0.1 watts per square centimeter.

8. The system of claim 1 wherein the plurality of actuators are embedded within a composite leading edge of the component with respect to a direction of movement of the component.

9. The system of claim 1 wherein the plurality of actuators are each positioned proximate to and coupled to the inner facing surface in an evenly spaced manner.

10. The system of claim 1 wherein the component comprises at least a part of at least one of the following:

an aircraft wing, an aircraft tail, an air foil, an aircraft rudder, an aircraft control surface such as a flap or an elevator, a wind turbine blade, an engine intake surface, a helicopter rotor blade, and a refrigeration coil cooling fin.

11. The system of claim 1 wherein the component comprises at least one of:

an alloy, a composite material, graphite, a polymer, a thermoplastic or fiberglass.

12. The system of claim 1 wherein the control unit is configured to selectively drive two or more of the plurality of actuators in time in a sequence relative to each other, the two or more of the plurality of actuators arranged in a pattern extending across at least a portion of the inner facing surface.

13. The system of claim 1 wherein the control unit is configured to selectively drive two or more of the plurality of actuators in time in a sequence relative to each other, the two or more of the plurality of actuators arranged in a pattern extending from one portion of the inner facing surface in a linear sweep to another portion of the inner facing surface.

14. The system of claim 1 wherein the plurality of actuators are arranged in a plurality of zones each zone corresponding to a respective region of the inner facing surface, wherein the control unit is configured to selectively drive the plurality of actuators of each of the plurality of zones in time relative to others of the plurality of zones.

15. The system of claim 14 wherein the control unit is configured to drive the plurality of actuators of at least two zones at different frequencies.

16. The system of claim 1 wherein the control unit is configured to drive the one or more of the plurality of actuators at the one or more constant frequencies.

17. The system of claim 1 wherein the control unit is configured to selectively drive the one or more of the plurality of actuators at a plurality of predetermined frequencies within a predetermined time period.

18. The system of claim 17 further comprising at least one sensor coupled to the one or more of the plurality of actuators, the at least one sensor configured to sense an impedance of the one or more of the plurality of actuators when being driven by the control unit.

19. The system of claim 18 wherein the control unit is coupled to the at least one sensor and is configured to switch a driving frequency of the one or more of the plurality of actuators based on signaling received from the at least one sensor.

20. The system of claim 1 wherein the plurality of actuators are each configured to introduce the displacement of the corresponding locations of the outer facing surface in the three dimensions including transverse and longitudinal directions.

21. The system of claim 1 wherein the control unit is configured to automatically drive the one or more of the plurality of actuators.

22. The system of claim 1, wherein each solid-state electric actuator comprises a piezo-kinetic actuator.

23. The system of claim 1, wherein each solid-state electric actuator comprises a piezoelectric material.

24. The system of claim 1, wherein the plurality of actuators each comprising a flexible sheet substantially conforming to the curvature of the inner facing surface.

25. The system of claim 1, wherein the plurality of actuators substantially conform to and attach to the curvature of the inner facing surface.

26. The system of claim 1, wherein the plurality of actuators are each configured to introduce the displacement of the outer facing surface in three dimensions to contact a solid layer interface of the existing ice formations contacting the corresponding locations of the outer facing surface.

27. The system of claim 1, wherein the plurality of actuators are each configured to introduce the displacement of the outer facing surface in three dimensions to perform one or both of inhibiting the formation of ice on the at least the corresponding locations of the outer facing surface and breaking up the existing ice formations on the at least the corresponding locations of the outer facing surface without active heating of the corresponding locations of the outer facing surface.

28. The system of claim 1, wherein at least one of the plurality of actuators is configured to introduce the displacement of the outer facing surface and is coupled to a sensor that monitors an impedance of the actuator.

29. The system of claim 1, further comprising a sensor coupled to one of the plurality of actuators, the sensor configured to sense an impedance of the one of the plurality of actuators when being driven by the control unit in order to detect icing conditions.

30. The system of claim 1 wherein the control unit is configured to drive the one or more of the plurality of actuators at one or more frequencies including one or more frequencies at or near one or more resonant frequencies of the outer facing surface.

31. The system of claim 1, wherein the control unit is configured to drive one or more of the plurality of actuators at the one or more frequencies and including one of a resonant frequency of the outer facing surface which ice has not formed thereon and a resonant frequency of the outer facing surface having ice formed thereon.

32. The system of claim 1, wherein the control unit is configured to drive the one or more of the plurality of actuators at one or more frequencies between 1 Hz and 1 kHz.

33. A method for use with an aircraft comprising:

driving a plurality of actuators each positioned proximate to and coupled to an inner facing surface of a component of the aircraft also having an outer facing surface, wherein each of the plurality of actuators comprises a solid-state electric actuator, the plurality of actuators coupled at locations of the inner facing surface directly opposing corresponding locations of the outer facing surface; and

driving one or more of the plurality of actuators at one or more frequencies such that each of the plurality of actuators introduce a displacement of the outer facing surface in three dimensions to perform one or both of inhibiting a formation of ice on at least the corresponding locations of the outer facing surface and breaking up existing formations of the ice on at least the corresponding locations of the outer facing surface;

wherein the plurality of actuators are flexible and substantially conform to a curvature of the locations of the inner facing surface.