Electroadhesive devices
Described herein is electroadhesion technology that permits controllable adherence between two objects. Electroadhesion uses electrostatic forces of attraction produced by an electrostatic adhesion voltage, which is applied using electrodes in an electroadhesive device. The electrostatic adhesion voltage produces an electric field and electrostatic adherence forces. When the electroadhesive device and electrodes are positioned near a surface of an object such as a vertical wall, the electrostatic adherence forces hold the electroadhesive device in position relative to the surface and object. This can be used to increase traction or maintain the position of the electroadhesive device relative to a surface. Electric control of the electrostatic adhesion voltage permits the adhesion to be controllably and readily turned on and off.
1. An electroadhesive system, comprising:
a first object having a first surface region adapted for contact with other objects;
a second object having a deformable surface adapted to contact the first surface region of said first object, wherein a surface interface area is created when said first and second objects come into contact with each other; and
at least one pair of electrodes located proximate to the surface interface area between the first and second objects and configured to apply a first voltage at a first location proximate to the surface interface area and a second voltage at a second location proximate to the surface interface area, wherein the difference in voltage between the first voltage and second voltage includes an electrostatic adhesion voltage that produces an electrostatic force between said first and second objects that is suitable to adhere the first and second objects together when the electrostatic adhesion voltage is applied, and wherein at least a portion of the deformable surface is adapted to move closer to the first surface region of the first object when the electrostatic adhesion voltage is applied.
2. The electroadhesive system of claim 1 , wherein the deformable surface includes a surface of a compliant material having an elastic modulus less than about 10 MPa.
3. The electroadhesive system of claim 1 , wherein the deformable surface includes a material or structure that is bendable but not substantially elastically extendable.
4. The electroadhesive system of claim 1 , wherein the deformable surface comprises a thin metal layer.
5. The electroadhesive system of claim 1 , wherein the electrostatic force between the first and second objects is suitable to maintain a current position of the first and second objects with respect to each other despite the presence of a particulate disposed between the first surface region and the deformable surface.
6. The electroadhesive system of claim 1 , further comprising:
a support structure mechanically coupled to the deformable surface.
7. A method of electrostatically adhering two separate objects, comprising:
placing a first object and second object in contact with each other, wherein said first object includes a first surface region and said second object includes a deformable surface that is placed in close proximity to the first surface region;
applying an electrostatic adhesion voltage difference between a first electrode at a first location and a second electrode at a second location of at least one of said first and second objects while said first and second objects are in close proximity to each other;
increasing the amount of surface area contact between the first surface region and the deformable surface;
adhering the first and second objects together using an electrostatic attraction force provided by the electrostatic adhesion voltage difference; and
maintaining the electrostatic attraction force while the first surface region and deformable surface are in contact with each other.
8. The method of claim 7 , wherein the deformable surface is included in a deformable insulation material that includes an elastic modulus less than about 10 MPa.
9. The method of claim 7 , wherein said step of increasing the amount of surface area contact includes moving a portion of the deformable surface closer to the first surface region.
10. The method of claim 7 , wherein the first electrode and the second electrode are located on said first object and are both in contact with the surface of the second object when the differential voltage is applied.
11. An electroadhesive device, comprising:
a first surface region facing a first direction and adapted for contact with a first external object;
a second surface region facing a second direction and adapted for contact with a second external object, wherein the second surface region is separate from the first surface region, the second direction is substantially different from the first direction, and the second external object is separate from the first external object; and
at least one pair of electrodes located proximate to both of said first surface region and said second surface region, said at least one pair of electrodes being configured to apply at least one electrostatic adhesion voltage that produces at least one electrostatic force that is suitable to adhere both the first external object to the electroadhesive device and the second external object to the electroadhesive device when the at least one electrostatic adhesion voltage is applied, wherein said at least one pair of electrodes includes a first pair of electrodes configured to produce a first electroadhesive force that is suitable to adhere the first external object to the electroadhesive device, and a second pair of electrodes separate from said first pair of electrodes and configured to produce a second electroadhesive force that is suitable to adhere the second external object to the electroadhesive device.
12. The electroadhesive device of claim 11 , wherein said at least one electrostatic force is a single electrostatic force that operates to adhere both of the first external object and second external object simultaneously.
13. The electroadhesive device of claim 11 , wherein said first and second surface regions are on opposite sides of the electroadhesive device.
14. The electroadhesive device of claim 11 , wherein the overall electroadhesive device defines a relatively flat profile.
15. The electroadhesive device of claim 11 , wherein the overall electroadhesive device is smaller than both of the first external object and the second external object, whereby the first and second external objects are effectively coupled together via the electroadhesive device.
16. The electroadhesive device of claim 11 , wherein at least a portion of said first surface region, said second surface region, or both, includes a deformable part that is adapted to move closer to its respectively adhered external object when the at least one electrostatic adhesion voltage is applied.
17. The electroadhesive device of claim 16 , wherein the deformable part includes a compliant material having an elastic modulus less than about 10 MPa.
18. The electroadhesive system of claim 16 , wherein the deformable part includes a material or structure that is bendable but not substantially elastically extendable.