Abstract: A stress-wave actuator is disclosed in which a stressed, elastic member is in frictional contact with a rigid element. A stress altering element moves along the elastic element, temporarily altering stress in a portion of it, moving the stressed element relative to the rigid element. When the rigid element is an open ended enclosure, the elastic member is shaped and sized to be slightly larger in circumference than the open ended enclosure so that the elastic member is compressed and stressed. Movingly reducing the stress in a portion of the elastic member causes it to be displaced relative to the rigid member. Stress alteration may be effected by magnetic, electric or physical means depending of the physical nature of the elastic element. The stress wave actuator may be configured to act as a high torque motor, a high gear ration motion transfer device, and as a clutch.

Abstract: Methods for creating undulating structures are disclosed in which an elastic sheet and a rigid restraining member having different curvatures are joined. The structures incorporate stopping members, such as stopped grooves, to manage the transverse deformations of the elastic sheet. The joint is such that the transverse deformations may migrate along the undulating structure in a coordinated, wave, either to gather kinetic energy, or to propel the structure relative to a fluid. To facilitate such a wave, the elastic sheet can be joined to the retaining member via passive stopping members that oscillate about their points of attachment to the retaining member. These are also constructed to limit the elastic sheet from reverting to its original configuration. The retaining member can be annular structures, and the elastic sheet members can be tubular. Stopping members can be actuated to power the transverse deformations of the elastic sheet to oscillate.

Abstract: A stress-wave actuator is disclosed in which a stressed, elastic member is in frictional contact with a rigid element. A stress altering actuation travels along the elastic element, temporarily and sequentially altering the stress in a portion of it, thereby moving the stressed element relative to the rigid element. When the rigid element is an enclosure, and the elastic member is shaped and sized to be slightly larger in circumference than the enclosure, the elastic member is compressed and stressed. Altering the stress temporally and sequentially in portions of the elastic member causes it to be displaced relative to the rigid member. Stress alteration may be effected by magnetic, electric or physical means depending of the physical nature of the elastic element. The stress wave actuator may be configured to act as a high torque motor, a high gear ratio motion transfer device, and as a clutch.

Abstract: A method of providing motion using a loop-band device is disclosed. An outer, restraining loop constrains an inner, buckling loop to form a buckled mode having one or more buckles. An activation force generated in one of buckles provides a stress, resulting in a change of configuration of the buckling loop that produces movement of the restraining loop. Depending on the composition of the buckling loop, the stress is generated via heat, light, an electric current or voltage, a magnetic field, or a combination thereof. The restraining loop is a suitably thin, relatively inextensible but flexible material. The buckling loop is a suitably thin, relatively flexible, reactive material that develops stress when subject to suitable activation forces. Suitable reactive materials include electroactive polymers, electrostrictive materials, magnetostrictive materials and materials having a high coefficient of linear, thermal expansion. The motion is linear or rotary, depending on device configuration.

Abstract: A buckling loop rotary motor is disclosed that has a stator, an activatable buckling loop and a rotor. The buckling loop is made of a springy, base band and an activatable active band. An applied force actuates a portion of loop, causing a localized change of curvature. When propagated along the buckling loop, the changed curvature causes rotation of the rotor. In a bi-metallic embodiment, the thermally actuated active band expands by at least 1% more than the base band, effect a localized change of curvature that drives the rotor. Thermal activation is by heating or cooling, or a combination thereof. In an electroactive polymer (EAP), the active acrylic or silicone EAP is actuated by an electrostatic charge. The change in thickness, and therefore, length, of the active EAP relative to the inactive, base material causes a local change of curvature of the loop that drives rotation of the rotor.

Abstract: A buckling loop rotary motor is disclosed that has a stator, an activatable buckling loop and a rotor. The buckling loop is made of a springy, base band and an activatable active band. An applied force actuates a portion of loop, causing a localized change of curvature. When propagated along the buckling loop, the changed curvature causes rotation of the rotor. In a bi-metallic embodiment, the thermally actuated active band expands by at least 1% more than the base band, effect a localized change of curvature that drives the rotor. Thermal activation is by heating or cooling, or a combination thereof. In an electroactive polymer (EAP), the active acrylic or silicone EAP is actuated by an electrostatic charge. The change in thickness, and therefore, length, of the active EAP relative to the inactive, base material causes a local change of curvature of the loop that drives rotation of the rotor.

Abstract: A method of providing motion using a loop-band device is disclosed. An outer, restraining loop constrains an inner, buckling loop to form a buckled mode having one or more buckles. An activation force generated in one of buckles provides a stress, resulting in a change of configuration of the buckling loop that produces movement of the restraining loop. Depending on the composition of the buckling loop, the stress is generated via heat, light, an electric current or voltage, a magnetic field, or a combination thereof. The restraining loop is a suitably thin, relatively inextensible but flexible material. The buckling loop is a suitably thin, relatively flexible, reactive material that develops stress when subject to suitable activation forces. Suitable reactive materials include electroactive polymers, electrostrictive materials, magnetostrictive materials and materials having a high coefficient of linear, thermal expansion. The motion is linear or rotary, depending on device configuration.

Abstract: The EFFICIENT POWER CONVERSION APPARATUSES, METHODS AND SYSTEMS include circuits for efficiently converting electrical energy to mechanical energy and vice-versa, such as within a multitude of ElectroActive Polymer (EAP) transducers. Embodiment may support a multitude of EAP transducers while also being capable of directing the movement of energy between electrical and mechanical forms in either direction. In another aspect, an efficient mode of transferring mechanical energy is discussed, via one or more strained and paired elastic transducers coupled to a potential energy reservoir.