Abstract: Sheath-run artificial muscles (or SRAMs) are described in which the dimensional changes and/or modulus changes of a sheath on the surface of a twisted or coiled host yarn or fiber drives torsional and tensile actuation. The sheath-core artificial muscle includes a sheath on a coiled core yarn or fiber that has inserted twist, in which the sheath does not include a yarn, the coiled core yarn or fiber includes a core yarn or fiber, the sheath can change volume, modulus, or a combination thereof when actuated by an influence source to drive actuation, and the influence source is selected from a group consisting of absorption processes, desorption processes, changes in temperature, changes in external pressure, changes in a magnetic field, changes in an electric field, exposures to actinic radiation, electrochemical charge and discharge, chemical reactions, and combinations thereof.

Abstract: Cooling by a twist-untwist process, by a stretch-release process for twisted, coiled, or supercoiled yarns or fibers, and methods and systems thereof. High mechanocaloric cooling results from release of inserted twist or from stretch release for twisted, coiled, or supercoiled fibers, including natural rubber fibers, NiTi wires, and polyethylene fishing line. Twist utilization can increase cooling and cooling efficiencies. A cooler using twist insertion and release can be shorter and smaller in volume than a cooler that requires a large elastomeric elongation. The cooler system can be utilized in mechanochromic textiles and remotely readable tensile and torsional sensors.

Abstract: Sheath-run artificial muscles (or SRAMs) are described in which the dimensional changes and/or modulus changes of a sheath on the surface of a twisted or coiled host yarn or fiber drives torsional and tensile actuation. The sheath-core artificial muscle includes a sheath on a coiled core yarn or fiber that has inserted twist, in which the sheath does not include a yarn, the coiled core yarn or fiber includes a core yarn or fiber, the sheath can change volume, modulus, or a combination thereof when actuated by an influence source to drive actuation, and the influence source is selected from a group consisting of absorption processes, desorption processes, changes in temperature, changes in external pressure, changes in a magnetic field, changes in an electric field, exposures to actinic radiation, electrochemical charge and discharge, chemical reactions, and combinations thereof.

Abstract: Cooling by a twist-untwist process, by a stretch-release process for twisted, coiled, or supercoiled yarns or fibers, and methods and systems thereof. High mechanocaloric cooling results from release of inserted twist or from stretch release for twisted, coiled, or supercoiled fibers, including natural rubber fibers, NiTi wires, and polyethylene fishing line. Twist utilization can increase cooling and cooling efficiencies. A cooler using twist insertion and release can be shorter and smaller in volume than a cooler that requires a large elastomeric elongation. The cooler system can be utilized in mechanochromic textiles and remotely readable tensile and torsional sensors.