AEROFOIL MEMBER

• US 20090308124A1
• Filed: 06/08/2009
• Published: 12/17/2009
• Est. Priority Date: 12/08/2006
• Status: Active Grant

• Current Assignee: Imperial Innovations Limited (Imperial College London)
• Original Assignee: Imperial Innovations Limited (Imperial College London)
• Inventors: Iannucci, Lorenzo
• Granted Patent: US 8,186,631 B2
• Time in Patent Office: Days
• US Class Current: 72/54
• CPC Class Codes: B64C 3/48 by relatively-movable parts of wing structures
• CPC Class Codes: Y10T 428/24149 Honeycomb-like

Abstract

An aerofoil member (10) comprising a ‘smart core’ (14) and a flexible skin (12). The core comprises sheet material elements (16) forming adjoining cells (18). The length of the elements can be changed, for example using the piezo-electric effect, to alter the cross-sectional shape of the aerofoil without changing the peripheral length. Thus the shape of the aerofoil may be changed to suit different flight conditions, or to mimic the effect of control surfaces.

Claims

1. An aerofoil member comprising a flexible outer skin supported by a structural core, the core comprising a plurality of sheet material elements which elements are joined together to form adjoining cells, at least some of the elements having an actuator which is actuable to adjust at least one dimension of the respective element, so as to adjust the cross sectional shape of the aerofoil, the elements at the periphery of the core being pivotally joined to the skin at an edge thereof.

2. An aerofoil member as claimed in claim 1 in which the elements are formed of piezo-electric material, and the actuators are electrodes formed on the material.

3. An aerofoil member as claimed in claim 1, in which the flexible skin comprises a composite material.

4. An aerofoil member as claimed in claim 3, in which the flexible skin comprises a polyurethane material reinforced with glass or carbon fibres.

5. An aerofoil member as claimed in claim 1, in which the skin is arranged such that at least one predetermined aerofoil shape corresponds to a natural mode of the skin material.

6. An aerofoil member as claimed in claim 1, in which the elements are joined to the skin by polypropylene material.

7. An aerofoil member as claimed in claim 1, in which the elements each comprise a plurality of layers of laminated piezo-ceramic material.

8. A method of changing the cross-sectional shape of an aerofoil member as claimed in claim 1, comprising applying an actuator signal to the actuator of each element so as to alter the cross-sectional shape without substantially changing the peripheral length of the aerofoil.