In an example, an engine includes a thermal expansion unit comprising expansion material that expands in response to a temperature increase of the expansion material and contracts in response to a temperature decrease of the expansion material. The engine includes a structure comprising a heat receiving region, wherein at least a portion of the thermal expansion unit is disposed within the structure. The heat receiving region is configured to transfer thermal energy from a source of thermal energy to the expansion material through a first thermal energy transference path. The transfer of thermal energy to the thermal expansion unit causes expansion of the expansion material within the thermal expansion unit. The expansion of the expansion material causes an increase in length of the thermal expansion unit. The increase in length of the thermal expansion unit causes establishment of a second thermal energy transference path through which thermal energy is transferred from the expansion material to outside the thermal expansion unit.

A linear drive comprises: a lever having a through bore; a rod which extends through the bore; a bearing supporting the rod; a shape memory alloy connected to the lever and a first fixed bearing, the shape memory alloy exerting a tensile force on the lever when electrical power is applied; and a restoring element connected to the lever and a second fixed bearing, the restoring element exerting a restoring force on the lever and counter to the tensile force. In a first state, the lever is tilted making a non-positive connection between the lever and the rod. In a second state the lever is displaced in parallel to and in the direction of the tensile force. In a third state the lever is tilted back releasing the non-positive connection. In a fourth state, the lever is displaced in parallel to and in the direction of the restoring force.

Systems and methods are provided for a mechanical actuator based on a fiber optic platform. A material that is configured to be activated by light may be incorporated into an optical fiber that serves as both an actuator and a power delivery network. This platform is adaptable to different materials, types of motions, and length scales and allows for precise delivery of photons to the material.

A hybrid actuation device includes an artificial muscle, a first plate coupled to a second plate, and a shape memory alloy wire. The artificial muscle includes a housing, a first electrode and a second electrode, and a dielectric fluid. The housing includes a first film layer, a second film layer, an electrode region, and an expandable fluid region. The first electrode and the second electrode are each disposed in the electrode region of the housing. The dielectric fluid is disposed within the housing. The first plate and the second plate are positioned within the housing, the first plate positioned between the first film layer and the first electrode, and the second plate positioned between the second film layer and the second electrode. The shape memory alloy wire extends from the first plate to the second plate and through the dielectric fluid.

A thermally driven elastocaloric system and a method for generating at least one of a heating potential and a cooling potential are provided. The thermally driven elastocaloric system includes a first shape memory alloy (SMA) member, a second shape memory alloy (SMA) member, and a connection mechanism configured between the distal end of the first SMA member and the distal end of the second SMA member. The connection mechanism is configured to transfer a force between the first SMA member and the second SMA member. The transfer of a compressive force to an SMA member may generate a heating potential in the SMA member, and the transfer of a tensile force to an SMA member may generate a cooling potential in the SMA member. Whether a compressive force or a tensile force is transferred may be dependent on whether heat is transferred to or from a SMA member.

A hybrid actuation device includes an artificial muscle, a first plate coupled to a second plate, and a shape memory alloy wire. The artificial muscle includes a housing, a first electrode and a second electrode, and a dielectric fluid. The housing includes a first film layer, a second film layer, an electrode region, and an expandable fluid region. The first electrode and the second electrode are each disposed in the electrode region of the housing. The dielectric fluid is disposed within the housing. The first plate and the second plate are positioned within the housing, the first plate positioned between the first film layer and the first electrode, and the second plate positioned between the second film layer and the second electrode. The shape memory alloy wire extends from the first plate to the second plate and through the dielectric fluid.

An actuator that includes a shell, a ring structure within the shell, a shape-memory material wire fixed at opposite points of the ring structure to extend in a first direction across a width of the ring structure, and a cooling fluid provided within the shell and in fluid communication with the shape-memory material wire. When the shape-memory material wire is heated, the shape-memory material wire contracts in the first direction to reduce the width of the ring structure and increases a height of the ring structure extending in a second direction perpendicular to the first direction.

A driving mechanism is provided in the present disclosure, including a fixed portion, a first movable portion, and a first driving assembly. The first movable portion moves relative to the fixed portion in a first direction. The first driving assembly drives the first movable portion to move relative to the fixed portion in the first direction. The first driving assembly includes a coil and a magnetic element corresponding to the coil.

An artificial muscle stack that includes a plurality of artificial muscle layers. Each artificial muscle layer includes one or more artificial muscles having a housing with an electrode region and an expandable fluid region, a dielectric fluid housed within the housing, and an electrode pair having a first and second electrode positioned in the electrode region. The first and second electrodes each include two or more tab portions and two or more bridge portions. The two or more bridge portions interconnects adjacent tab portions. At least one of the first and second electrode includes a central opening positioned between the tab portions and encircling the expandable fluid region. The plurality of artificial muscle layers are arranged such that the expandable fluid region of the artificial muscles of each artificial muscle layer overlaps at least one tab portion of one or more artificial muscles of an adjacent artificial muscle layer.

The invention provides a heat pump system and method comprising a first Shape-Memory Alloy (SMA) or Negative Thermal Expansion (NTE) elastocaloric core positioned in a housing and adapted to absorb heat and store energy in response to a first fluid inputted at a first temperature. The housing is configured to receive the first fluid at a first temperature via an inlet to cause the first SMA or NTE elastocaloric core to change state. A device is configured to apply stress on the first SMA or NTE core in the housing to cause the SMA or NTE elastocaloric core to change state, releasing heat/energy and causing the SMA/NTE to heat up. A second fluid at a higher temperature is inputted and then subsequently heated further as a result of heat transfer. A second Shape-Memory Alloy (SMA) or Negative Thermal Expansion (NTE) or elastocaloric core is positioned in a cascade arrangement with the first core, but exhibiting a higher activation temperature. The higher temperature fluid leaving core 1 is inputted into core 2, resulting in a larger net temperature lift than could be achieved with a single core. In the alternative, in a cooling system, to achieve a lower temperature drop, the second core in the cascade can exhibit a lower activation temperatures than the first core. The cycle focus is on the endothermic stress release component where the SMA/NTE/elastocaloric core absorbs energy from the fluid. The first core results in a fluid stream drop and that then enters the second core with lower activation temperatures, resulting in a further drop of the output fluid during the cooling half of the cycle.