Morphing cellular structure

• US 7,582,349 B1
• Filed: 02/03/2005
• Issued: 09/01/2009
• Est. Priority Date: 02/03/2005
• Status: Expired due to Fees

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: McKnight, Geoffrey P., Barvosa-Carter, William, Massey, Cameron, Herrera, Guillermo A.
• Primary Examiner(s): Speer; Timothy M
• Assistant Examiner(s): BALDWIN, GORDON
• Application Number:
  US11/051,758
• Time in Patent Office: 1,671 Days
• Field of Search: 428/68, 428/116, 428/604, 428/593, 428/598, 428/686, 298/972, 296/187.02, 296/187.03, 296/187.08, 296/187.09, 293/107
• US Class Current: 428/116
• CPC Class Codes: F03G 7/005 Electro-chemical actuators; Actuators having a material for absorbing or desorbing gas, e.g. a metal hydride; Actuators using the difference in osmotic pressure between fluids; Actuators with elements stretchable when contacted with liquid rich in ions, with UV light, with a salt solution
• CPC Class Codes: F03G 7/0121 Electroactive polymers
• CPC Class Codes: F03G 7/06 using expansion or contraction of bodies due to heating, cooling, moistening, drying or the like using thermal expansion of non-vaporising liquids F01K
• CPC Class Codes: F03G 7/0612 using polymers
• CPC Class Codes: F03G 7/06147 Magnetic shape memory alloys, e.g. ferro-magnetic alloys
• CPC Class Codes: F03G 7/065 using a shape memory element
• CPC Class Codes: Y10T 29/49622 Vehicular structural member making
• CPC Class Codes: Y10T 428/1234 Honeycomb, or with grain orientation or elongated elements in defined angular relationship in respective components [e.g., parallel, inter- secting, etc.]
• CPC Class Codes: Y10T 428/12375 having member which crosses the plane of another member [e.g., T or X cross section, etc.]
• CPC Class Codes: Y10T 428/12417 Intersecting corrugating or dimples not in a single line [e.g., waffle form, etc.]
• CPC Class Codes: Y10T 428/12986 Adjacent functionally defined components
• CPC Class Codes: Y10T 428/231 Filled with gas other than air; or under vacuum
• CPC Class Codes: Y10T 428/24149 Honeycomb-like

Abstract

The present invention relates to a morphing cellular structure. The morphing cellular structure comprises a group of unit cells with each unit cell configured to have a cellular geometry. The group unit cells are formed of an active material, where the active material has both a first state and a second state. The active material is responsive to an actuation signal such that when the actuation signal is actuated, the active material is deformed from the first state to the second state, thereby changing the volume of each unit cell affected by the actuation of the actuation signal and morphing the cellular structure. Furthermore, both a passive material and at least one additional active material can be attached with the active material, allowing a user to selectively change the shape of the cellular structure.

Claims

1. A morphing cellular structure, comprising a group of unit cells with each unit cell having a cellular geometry, the group of unit cells formed of a first active material, where the first active material has a first state and a second state, and where each unit cell has a configuration where the configuration of each unit cell, while the first active material is in the first state, is different from the configuration of each unit cell while the first active material is in the second state, and where the first active material is responsive to a first actuation signal such that when the first actuation signal is actuated, the active material is deformed from the first state to the second state, thereby changing the configuration of each unit cell affected by the actuation of the first actuation signal and morphing the cellular structure,

wherein the first actuation signal is a signal selected from a group consisting of a temperature change, redox reaction, pH change, electromagnetic field, chemical reaction, electric current, electric field, and magnetic field;

and

wherein the active material is deformable from both a first state to a second state and from a second state to a first state such that the deployment is a re-settable deployment where the active material is re-settable through an external reset signal, allowing for at least one additional deployment, the re-settable deformation being selected from a group of consisting of deforming from the first state to the second state upon receiving the first actuation signal and deforming from the second state to the first state when the first actuation signal is removed, and deforming from the first state to the second state when the first actuation signal is removed and deforming from the second state to the first state when the first actuation signal is received.

2. A morphing cellular structure as set forth in claim 1, wherein the configuration is measured as volume, where each unit cell has a volume where the volume of each unit cell, while the first active material is in the first state, is different from the volume of each unit cell while the first active material is in the second state.

3. A morphing cellular structure as set forth in claim 2, wherein the cellular geometry is selected from a group consisting of cubic, tetragonal, orthorhombic, rhombohedral, hexagonal, monoclinic, and triclinic.

4. A morphing cellular structure as set forth in claim 3, wherein the cellular structure is configured to be morphed by actuating the first actuation signal in a manner selected from a group consisting of the active material being a self-sensor and deforming when self-sensing the first actuation signal;

the first actuation signal being actively applied to all cells;

the first actuation signal being actively applied to a region of cells;

the first actuation signal being actively applied to a single cell;

the first actuation signal being actively removed;

each cell being affected by a neighboring cell; and

cells reacting to a first actuation signal from neighboring cells or a propagated signal.

5. A morphing cellular structure as set forth in claim 4, wherein the active material is a material selected from a group consisting of shape memory alloys, shape memory polymers, piezoelectric bimorph, ionic polymer metal composites, conductive polymers, ionic polymer gels, ferromagnetic shape memory alloys, ferromagenetics, liquid crystal elastomers, dielectric elastomers, polyacrylonitrile fibers, and hard piezos.

6. A morphing cellular structure as set forth in claim 5, wherein the morphing cellular structure has a size and each unit cell in the morphing cellular structure is between approximately one one-thousandths and one third of size of the morphing cellular structure.

7. A morphing cellular structure as set forth in claim 6, wherein the first state can be altered by forcedly altering the cellular geometry.

8. A morphing cellular structure as set forth in claim 7, further comprising a second group of unit cells connected with a first group of unit cells, with each unit cell configured to have a cellular geometry, the second group of unit cells formed of a second active material, where the second active material has both a third state and a fourth state, and where each unit cell has a volume where a volume of each unit cell while the second active material is in the third state is different from the volume of each unit cell while the second active material is in the fourth state, and where the second active material is responsive to a second actuation signal such that when the second actuation signal is actuated, the second active material is deformed from the third state to the fourth state, thereby changing the volume of each unit cell receiving the second actuation signal and morphing the cellular structure, thereby allowing a user to selectively morph the cellular structure by using at least one of the first and second actuation signals.

9. A morphing cellular structure as set forth in claim 8, further comprising a passive material connected with the active material.

10. A morphing cellular structure as set forth in claim 9, wherein the active material is attached between at least two sections of passive material such that the active material functions as a hinge joint, whereby actuation of the active material forces a bending moment at the hinge joint.

11. A morphing cellular structure as set forth in claim 9, wherein the active material is attached with the passive material at a hinge joint such that actuation of the active material forces a bending moment at the hinge joint.

12. A morphing cellular structure as set forth in claim 9, wherein the cellular structure is configured to be a deployable structure.

13. A morphing cellular structure as set forth in claim 9, wherein the cellular structure is configured to be attached with a window and function as a deployable window shade, such that when the first actuation signal is applied, the deployable window shade changes its shape to change its configuration with respect to the window.

14. A morphing cellular structure as set forth in claim 9, wherein the cellular structure is configured to hold a cup and change its shape to conform its shape with a shape of an inserted cup, whereby after a cup is placed within the cellular structure, the first actuation signal can be applied to cause the cellular structure to conform its shape with the shape of the cup.

15. A morphing cellular structure as set forth in claim 9, wherein the cellular structure is configured to function as an air passage having a first side and a second side, and formed in such a shape that actuation of the air passage affects the flow of air from the first side to the second side, whereby when the first actuation signal is applied, the air passage changes its shape to affect passage of air through the air passage.

16. A morphing cellular structure as set forth in claim 9, wherein the cellular structure is configured to be used as an automobile surface, allowing a deformed automobile surface to return to an un-deformed state when the first actuation signal is actuated.

17. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to be morphed by receiving the first actuation signal in a manner such that the active material is a self-sensor and deforming when self-sensing the first actuation signal.

18. A morphing cellular structure as set forth in claim 1, wherein the first state can be altered by forcedly altering the cellular geometry.

19. A morphing cellular structure as set forth in claim 1, wherein the active material is a material selected from a group consisting of shape memory polymers, piezoelectric bimorph, ionic polymer metal composites, conductive polymers, ionic polymer gels, liquid crystal elastomers, dielectric elastomers, and hard piezos.

20. A morphing cellular structure as set forth in claim 1, further comprising a second group of unit cells connected with a first group of unit cells, with each unit cell configured to have a cellular geometry, the second group of unit cells formed of a second active material, where the second active material has both a third state and a fourth state, and where each unit cell has a volume where a volume of each unit cell while the second active material is in the third state is different from the volume of each unit cell while the second active material is in the fourth state, and where the second active material is responsive to a second actuation signal such that when the second actuation signal is applied, the second active material changes from the third state to the fourth state, thereby allowing a user to selectively morph the cellular structure by using at least one of the first and second actuation signals.

21. A morphing cellular structure as set forth in claim 1, further comprising a passive material connected with the active material.

22. A morphing cellular structure as set forth in claim 21, wherein the active material is attached with the passive material at a hinge joint such that actuation of the active material forces a bending moment at the hinge joint.

23. A morphing cellular structure as set forth in claim 21, wherein the active material is attached between at least two sections of passive material such that the active material functions as a hinge joint, whereby actuation of the active material forces a bending moment at the hinge joint.

24. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to be a deployable structure.

25. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to be attached with a window and function as a deployable window shade, such that when the first actuation signal is applied, the deployable window shade changes its shape to change its configuration with respect to the window.

26. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to hold a cup and change its shape to conform its shape with a shape of an inserted cup, whereby after a cup is placed within the cellular structure, the first actuation signal can be applied to cause the cellular structure to conform its shape with the shape of the cup.

27. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to function as an air passage having a first side and a second side, and formed in such a shape that actuation of the air passage affects the flow of air from the first side to the second side, whereby when the first actuation signal is applied, the air passage changes its shape to affect passage of air through the air passage.

28. A morphing cellular structure as set forth in claim 1, wherein the cellular structure is configured to be used as an automobile surface, allowing a deformed automobile surface to return to an un-deformed state when the first actuation signal is applied.

29. A morphing cellular structure as set forth in claim 1, wherein the cellular geometry of the cells in the group of unit cells is non-symmetrical.

30. A morphing cellular structure as set forth in claim 1, wherein each unit cell is extruded to form a three-dimensional (3-D) structure such that the morphing cellular structure allow for 3-D expansion and contraction.

31. A morphing cellular structure, comprising a group of unit cells with each unit cell having a cellular geometry, the group of unit cells formed of a first active material, where the first active material has a first state and a second state, and where each unit cell has a configuration where the configuration of each unit cell, while the first active material is in the first state, is different from the configuration of each unit cell while the first active material is in the second state, and where the first active material is responsive to a first actuation signal such that when the first actuation signal is actuated, the active material is deformed from the first state to the second state, thereby changing the configuration of each unit cell affected by the actuation of the first actuation signal and morphing the cellular structure;

and;

wherein the cellular geometry of the cells in the group of unit cells is an auxetic cellular geometry.