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A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof, wherein the

A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof, wherein the plurality of hook elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein the fiber and the shape memory alloy coating comprises a non-axisymmetric coating or deposition of the shape memory alloy about a portion of the fiber. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. Introducing a thermal activation signal to the plurality of hook elements causes a change in shape orientation, flexural modulus property, or a combination thereof that is effectively reduces the shear and/or pull off forces in the releasable engagement. In this manner, disengagement of the releasable fastener system provides separation of the hook portion from the loop portion under controlled conditions.

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1. A releasable fastener system comprising:a loop portion comprising a support and a loop material attached to the loop support;a hook portion comprising a hook support and a plurality of hook elements attached to the hook support, wherein the plurality of hook elements comprises a fiber and a shape

1. A releasable fastener system comprising:a loop portion comprising a support and a loop material attached to the loop support;a hook portion comprising a hook support and a plurality of hook elements attached to the hook support, wherein the plurality of hook elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein shape memory alloy coating deposited onto the fiber comprises a non-axisymmetric coating or deposition or the shape memory alloy about a portion of the fiber surface; andan activation device coupled to the plurality of hook elements, the activation device being operable to selectively provide a thermal activation signal to the shape memory alloy and change the shape orientation, the flexural modulus property, or a combination of the shape orientation and flexural modulus properties of the plurality of hook elements to reduce a shear force and/or a pull-off force of an engaged hook and loop portion. 2. The releasable fastener system of claim 1, wherein the fiber and the shape memory alloy coating deposited onto the fiber comprises a coating along a perimeter of the fiber defined by a plane extending parallel from a longitudinal central axis of the fiber. 3. The releasable fastener system of claim 2, wherein the coating along the perimeter of the fiber is limited to an engageable portion of the hook element. 4. The releasable fastener system of claim 1, wherein the fiber comprises a plastic, fabric, or a metal. 5. The releasable fastener system of claim 1, wherein the shape memory alloy comprises a nickel titanium based alloy, an indium-titanium based alloy, a nickel aluminum based alloy, a copper based alloy, a gold cadmium based alloy, an iron-platinum based alloys, silver-cadmium based alloys, indium-cadmium based alloys, manganese-copper based alloys, an iron palladium based alloys, combinations comprising at least one of the foregoing alloys. 6. The releasable fastener system of claim 1, wherein the hook support and the loop support comprises an inflexible material. 7. A process for operating a releasable fastener system, the process comprising:contacting a loop portion with a hook portion to form a releasable engagement, wherein the loop portion comprises a support and a loop material attached to the support, and wherein the hook portion comprises a support and a plurality of hook elements attached to the support, wherein the plurality of hook elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein the fiber and the shape memory alloy coating comprises a non-axisymmetric coating or deposition of the shape memory alloy about a portion of the fiber surface;maintaining constant shear and pull-off forces in the releasable engagement without introducing an energy signal;selectively introducing a thermal activation signal to the hook elements, wherein the thermal activation signal is effective to change a shape orientation, a flexural modulus property, or a combination thereof to the plurality of hook elements; andreducing the shear and/or pull off forces in the releasable engagement. 8. A hook portion for a releasable fastener system comprising: a support; anda plurality of hook elements attached to the support, wherein the plurality of hook, elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein the fiber and the shape memory alloy coating comprises a deposition of the shape memory alloy about a portion of the fiber surface, wherein the fiber and the shape memory alloy coating about the portion of the fiber are disposed along a perimeter of the fiber defined by a plane extending parallel from a longitudinal central axis of the fiber. 9. The hook portion of claim 8, wherein the coating along the perimeter of the fiber is limited to an engageable portion of the hook element. 10. The hook portion of claim 8, wherein the fiber is a material selected from the group consisting of a plastic, a fa bric, and metal. 11. The hook portion of claim 8, wherein the shape memory alloy comprises nickel titanium based alloys, indium-titanium based alloys, nickel aluminum based alloys, copper based alloys, gold cadmium based alloys, iron-platinum based alloys, silver-cadmium based alloys, indium-cadmium based alloys, manganese-copper based alloys, iron palladium based alloys, and combinations comprises comprising at least one of the foregoing alloys. 12. A releasable fastener system comprising:a loop portion comprising a support and a loop material attached to the support;a hook portion comprising a support and a plurality of hook elements attached to the support, wherein the plurality of hook elements comprises a fiber and a shape memory alloy coating deposited onto the fiber, and wherein the fiber and the shape memory alloy coating or deposition disposed on the surface of the fiber comprises a non-axisymmetric coating or deposition of the shape memory alloy about a portion of the fiber surface; andmeans for changing of the shape orientation, the flexural modulus property, or the combination thereof of the hook elements to reduce a shear force and/or a pull-off force of an engaged hook and loop portion.