Shape memory polymer devices

Abstract

Various shape memory polymer (SMP) devices are disclosed. Many of these SMP devices can be used as attachment and/or release mechanisms for any number of different applications. These SMP devices can use various characteristics of the SMP material to allow for various shape changes. These shape changes, in some embodiments, can be used to provide for release and/or attachment devices, for example, SMP bolts, SMP screws, SMP collars, SMP pillars, SMP panels, and/or SMP rivets, to name a few. An SMP device can include a first geometric state and a second geometric shape. The first geometric shape can restrict motion of two distinct objects relative to one another and the second geometrical shape can allow motion of two distinct objects relative to one another.

1 . A shape memory polymer device comprising:
 a body comprising a shape memory material having a first state and a second state,   wherein in the first state the body is coupled with two objects and restricts the motion of the two objects relative to one another,   wherein in the second state the body allows motion of the two distinct objects relative to one another, and   wherein the body in the first state has a shape distinct from the shape of the body in the second state.   
     
     
         2 . The shape memory polymer device according to  claim 1 , wherein in the first state the body is coupled with two or more objects and wherein in the second state the body allows motion of at least two distinct objects relative to one another. 
     
     
         3 . The shape memory polymer device according to  claim 1 , wherein the shape memory polymer device transitions from the first state to the second state when either the shape memory device is heated to a temperature near or above the glass transition temperature of the shape memory material and a force is applied on the shape memory device. 
     
     
         4 . The shape memory polymer device according to  claim 3 , wherein the force is an external force. 
     
     
         5 . The shape memory polymer device according to  claim 3 , wherein the force is an external force that is applied using a tool. 
     
     
         6 . The shape memory polymer device according to  claim 1 , further comprising a resistive heat element coupled with the body. 
     
     
         7 . The shape memory polymer device according to  claim 1 , further comprising a mechanism coupled with the body that applies a force on the body that forces the body to transition from the first state to the second state, and wherein the force is not sufficient to transition the body from the first state to the second state unless the body is heated to a temperature near or above the glass transition temperature of the shape memory material. 
     
     
         8 . The shape memory polymer device according to  claim 7 , wherein the mechanism comprises a spring. 
     
     
         9 . The shape memory polymer device according to  claim 8 , wherein the spring comprises a resistive heating element. 
     
     
         10 . The shape memory polymer device according to  claim 7 , wherein the mechanism is coupled directly with the body. 
     
     
         11 . The shape memory polymer device according to  claim 1 , wherein the shape memory polymer transitions to the second state through release of stored strain energy in the shape memory polymer material. 
     
     
         12 . The shape memory polymer device according to  claim 1 , wherein in the first state the body carries a load between the two objects. 
     
     
         13 . The shape memory polymer device according to  claim 12 , wherein in the second state a portion of the body collapses under the load when heated to a temperature above the glass transition temperature. 
     
     
         14 . The shape memory polymer device according to  claim 1 , wherein the relative motion between the two objects is inhibited by mechanical interference of a body. 
     
     
         15 . The shape memory polymer device according to  claim 14 , wherein the mechanical interference comprises at least one of a tab, a thread, or a factory head. 
     
     
         16 . The shape memory polymer device according to  claim 1 , wherein the body transitions from the first state to the second state by releasing stored energy in the shape memory material when heated to a temperature at or near a glass transition temperature of the shape memory material. 
     
     
         17 . A method comprising:
 providing a shape memory device in a system with two distinct objects, wherein the shape memory device is in a first state and the shape memory device comprises a shape memory material; and   coupling the two distinct objects by transforming the shape memory device from the first state into a second state.   
     
     
         18 . The method according to  claim 17 , wherein the transforming includes either or both of heating the shape memory device to a temperature near or above the glass transition temperature of the shape memory material and applying a force on the shape memory device. 
     
     
         19 . A method comprising:
 coupling two distinct objects using a shape memory device that is in a first state, wherein the shape memory device comprises a shape memory material; and   transforming the shape memory device from the first state into a second state, wherein in the second state the two distinct objects are decoupled.   
     
     
         20 . The method according to  claim 19 , wherein the transforming comprises either or both of heating the shape memory device to a temperature near or above the glass transition temperature of the shape memory material and applying a force on the shape memory device. 
     
     
         21 . A method for using a shape memory polymer attachment mechanism, the method comprising:
 fabricating a shape memory polymer attachment mechanism in an original shape, wherein the shape memory polymer attachment mechanism includes shape memory polymer material;   heating the shape memory polymer attachment mechanism to a temperature near or above the glass transition temperature of the shape memory polymer materials;   transitioning the shape memory polymer attachment mechanism into a second shape while heated to a temperature near or above the glass transition temperature of the shape memory polymer material; and   placing the shape memory polymer attachment mechanism in position for an application.