Abstract: A panel structure includes a composite facesheet and a stiffening core having a plurality of core members in an intersecting web configuration provided on the composite facesheet.

Abstract: An energy harvesting system includes a heat engine and a component. The heat engine includes a belt, a first member, and a second member. The belt includes a strip of material and at least one wire at least partially embedded longitudinally in the strip of material. The wire includes a shape memory alloy material. A localized region of the at least one wire is configured to change crystallographic phase between martensite and austenite and either contract or expand longitudinally in response to exposure to a first temperature or a second temperature such that the strip of material corresponding to the localized region also contracts or expands. The first member is operatively connected to the belt and moves with the belt in response to the expansion or contraction of the belt. The component is operatively connected to the first member such that movement of the first member drives the component.

Abstract: In one embodiment, provided is an actively tunable acoustic attenuator having a frame, a membrane within the frame, and a mass secured to the membrane. In another embodiment, provided is an actively tunable acoustic attenuator having a frame, a membrane within the frame, and a mass secured to the membrane. The membrane is coupled, either indirectly or directly, to the frame via a variable stiffness coupler. In another embodiment, provided is an actively tunable acoustic attenuator having a frame and a plurality of membrane layers within the frame. An active material is between at least two of the plurality of membrane layers. A mass is secured to at least one of the plurality of membrane layers.

Abstract: An energy harvesting system comprises a first region having a first temperature and a second region having a second temperature. A conduit is located at least partially within the first region. A heat engine configured for converting thermal energy to mechanical energy includes a shape memory alloy forming at least one generally continuous loop. The shape memory alloy is disposed in heat exchange contact with the first region and the second region. A carrier surrounds the conduit such that the carrier is driven to rotate around the conduit by the shape memory alloy in response to the temperature difference between the first region and the second region.

Abstract: An apparatus has a first structure, a second structure, and an activated seal. The second structure has a first position adjacent to the first structure such that the first structure is not in contact with the second structure. The activated seal is attached to at least one of the first structure and the second structure. The activated seal has a variable stiffness that may be changed in response to a stimuli such that the activated seal is capable of being deformed when at least one of the first structure and the second structure are moved relative to each other.

Abstract: A device for selectively controlling and varying a frictional force level at an interface between two bodies, includes a first contact body having at least one surface, a second contact body having at least one surface in physical communication with the first contact body, and an active material in operative communication with a selected one or both of the first contact body and the second contact body, wherein the active material is configured to undergo a change in a property upon receipt of an activation signal wherein the change in a property is effective to change the frictional force level at the interface between the at least one surface of the first contact body and the at least one surface of the second contact body.

Abstract: A reconfigurable fixture device system, including: a base member; a reconfigurable pad disposed on the base member, wherein the reconfigurable pad comprises a shape memory material configured to selectively conform to a surface contour of a workpiece; an activation device in operative communication with the shape memory material; a controller in operable communication with at least one of the reconfigurable pad, the activation device, and the base member; a plurality of sensors for sensing a parameter associated with at least one of the reconfigurable pad, the base member, the fixture device, and the workpiece, wherein the plurality of sensors is in operable communication with the controller; and an actuator in operable communication with the controller and the at least one of the reconfigurable pad, the base member, the fixture device, and the workpiece.

Abstract: A holding fixture operable to secure differing pluralities of positioned objects having differing geometric shapes, sizes, and/or dimensions, including an active material element configured to selectively enable, cause, or retain the securing engagement and/or return the fixture to a ready state when not in use.

Abstract: An apparatus has a first structure, a second structure, and an activated seal. The second structure has a first position adjacent to the first structure such that the first structure is not in contact with the second structure. The activated seal is attached to at least one of the first structure and the second structure. The activated seal has a variable stiffness that may be changed in response to a stimuli such that the activated seal is capable of being deformed when at least one of the first structure and the second structure are moved relative to each other.

Abstract: In some embodiments, a variable stiffness joint is provided which has a plurality of structural members with a variable stiffness material coupled between the plurality of structural members. The variable stiffness material may be selectively activated/inactivated to control the stiffness of the joint. Additional embodiments and implementations are disclosed.

Abstract: A variable stiffness segmented composite material including reinforcements embedded in a variable stiffness matrix and having a structure for precisely controlling the three-dimensional (3D) distribution and connectivity of the reinforcements in the variable stiffness matrix. The composite material includes a variable stiffness matrix and a plurality of rigidly interconnected reinforcements embedded within the variable stiffness matrix, the interconnected reinforcements being for mitigating a deformation of the composite material along a first direction by blocking a rigid body motion of the reinforcements with respect to one another in the first direction while allowing a deformation in a second direction differing from the first direction. That is, in one embodiment, the interconnected reinforcements are configured to move with respect to one another to allow for an in-plane deformation of the composite material while mitigating an out-of-plane deformation of the composite material.

Abstract: Systems for and methods of determining at least one mid-stroke position of an active material actuated load by causing a stress induced rapid change in electrical resistance within the active material element, or modifying an ancillary circuit, when the load is at the mid-stroke position(s).

Abstract: An engineered microstructure composite having an elastic or elastomeric matrix with distributed rigid reinforcements. One embodiment of the invention provides an elastomeric composite including an elastomeric matrix, a plurality of rigid reinforcements embedded within the elastomeric matrix, and a plurality of attachments (or ligaments) connected to the reinforcements to interconnect the rigid reinforcements to each other. Here, in this embodiment, the elastomeric composite has a composite reversible strain limit greater than 3 percent (%) (or, in one embodiment, greater than 5%) due to kinematics of the rigid reinforcements interconnected by the attachments and embedded within the elastomeric matrix.

Abstract: In one implementation, a method of fabrication of stretchable electronic skin is provided. The method may include receiving an elastic material net. An elastic conductor mesh is formed on the elastic material net. A device is electrically bonded to the elastic conductor mesh. The implementation may further include forming a mold comprising a net pattern on a substrate and creating the elastic material net by coating the mold with an elastic material precursor, and then removing the elastic net from the substrate with the elastic conductor thereon. In one embodiment, a stretchable electronic skin including a net structure having a non-conducting elastic material with an elastic conductor mesh formed on the non-conducting elastic material, and a device electrically connected to the elastic conductor mesh.

Abstract: Active texturing systems adapted for selectively and reversibly modifying the texture of a surface utilizing a plurality of discrete mechanisms in communication with the reconfigurable structure.

Abstract: A cable adapted for use as an actuator, adaptive structural member, or damper, includes a plurality of longitudinally inter-engaged and cooperatively functioning shape memory alloy wires.

Abstract: A method of controlling and/or predicting the remaining useful life of an active material actuator, such as a shape memory alloy wire, includes obtaining historical actuation data of an inherent system variable, such as electrical resistance, over a secondary variable, such as time, determining a normal operating envelope having upper and lower bounds based on the data, determining a current profile for a given actuation cycle, and comparing the shape of the current profile to the envelope to determine an out-of-bounds event.

Abstract: Active seal assemblies employing active materials that can be controlled and remotely changed to alter the seal effectiveness, wherein the active seal assemblies actively change modulus properties such as stiffness, shape orientation, and the like. In this manner, in seal applications tailored for vehicles such as in a vehicle door application, door opening and closing efforts can be minimized yet seal effectiveness can be maximized.

Abstract: Active texturing systems adapted for selectively and reversibly modifying the texture of a surface utilizing a variably foldable structure in communication with the surface, and active material actuation to enable and/or cause folding.

Abstract: A method of sensing an ambient heat transfer condition surrounding a shape memory alloy element includes heating the shape memory alloy element, sensing the resistance of the shape memory alloy element, and measuring the period of time taken to heat the shape memory alloy element to a pre-determined level of a resistance characteristic. The ambient heat transfer condition surrounding the shape memory alloy element is calculated by referencing a relationship between the period of time taken to heat the shape memory alloy to the pre-determined level of the resistance characteristic and the ambient heat transfer condition.