A method of controlling power delivered to a shape memory alloy, SMA, actuator wire arrangement, wherein the arrangement comprises a plurality of SMA actuator wires, comprising: the steps of: applying, at a PWM frequency, to each of the SMA actuator wires during respective active periods a succession of voltage pulses; and applying, during a resistance measurement period, to one of the plurality of SMA actuator wires a resistance measurement current pulse, wherein the resistance measurement period corresponds to the respective active period of one of the plurality of SMA actuator wires.

An actuation device may include a plurality of actuation units disposed about an axis. Each actuation unit of the plurality of actuation units may include a shape memory alloy component, an auxetic material component operationally coupled to the shape memory alloy component, and a power source operationally coupled to the shape memory alloy component. Additionally, the actuation device may include a control system operationally coupled to the power source, the control system is configured to actuate the shape memory alloy component through the power source. Further, when actuated, the shape memory alloy component moves in a direction outward from the axis to pull the auxetic material component, and the auxetic material component expands in a direction perpendicular to the movement direction of the shape memory alloy component.

The present disclosure provides an actuating device and a method for controlling an SMA actuator wire. The actuating device includes: a first support structure and a second support structure that are spaced from each other to define a movement space; a movable element received in the movement space; an SMA actuator wire configured to drive the movable element to move in the movement space; a detection element configured to detect movement information; and a control element configured to adjust a power state of the SMA actuator wire based on the movement information in such a manner that the SMA actuator wire is in a loose state after the SMA actuator wire drives the movable element to be fixed to the second support structure. This can alleviate the technical problem in the related art that the SMA actuator wire is prone to failure when the lens is suffering collision or falling.

The present disclosure provides an actuating device and a method for controlling an SMA actuator wire. The actuating device includes: a first support structure and a second support structure that are spaced from each other to define a movement space; a movable element received in the movement space; an SMA actuator wire configured to drive the movable element to move in the movement space; a detection element configured to detect movement information; and a control element configured to adjust a power state of the SMA actuator wire based on the movement information in such a manner that the SMA actuator wire is in a loose state after the SMA actuator wire drives the movable element to be fixed to the second support structure. This can alleviate the technical problem in the related art that the SMA actuator wire is prone to failure when the lens is suffering collision or falling.

Actuator assemblies comprising a core made up of a shape memory alloy wire and a coating containing a distribution of Phase Changing Material (PCM) particles with a given weight ratio between said particles and said shape memory alloy wire, and active cloths incorporating one or more of said actuator assemblies.

An actuation device (100) includes a plurality of actuation units (101) disposed about an axis (Ar). Each actuation unit of the plurality of actuation units (101) includes a shape memory alloy component (104a-104n), an auxetic material component (105a-105n) operationally coupled to the shape memory alloy component (104a-104n), and a power source (107a-107n) operationally coupled to the shape memory alloy component (104a-104n). Additionally, the actuation device (100) includes a control system (108) operationally coupled to the power source (107a-107n), the control system (108) is configured to actuate the shape memory alloy component (104a-104n) through the power source (108). Further, when actuated, the shape memory alloy component (104a-104n) moves in a direction outward from the axis (Ar) to pull the auxetic material component (105a-105n), and the auxetic material component expands in a direction perpendicular to the movement direction of the shape memory alloy component (104a-104n).

Actuator assemblies and methods of operating actuator assemblies are provided, in particular with the aim of reducing bearing jitter. In one approach an actuator assembly (1) is provided which has: a support element (4); a movable element (20) movable relative to the support element; an SMA component (80) connected between the movable element and the support element and arranged to cause movement of the movable element relative to the support element; a bearing (100) arranged to guide the movement of the movable element; and a controller (30) arranged to control energy supplied to the SMA component to thereby cause contraction and/or relaxation of the SMA component and to control movement of the movable element relative to the support element in a first direction so as to provide an actuation function, wherein the controller is arranged to, at least whilst the movable element starts to move in the first direction, control the movable element to cause it to be moving in a second direction orthogonal to the first direction.

A circuit arrangement to control at least one valve includes at least one actuator with at least one positioning element adjustable between at least one first position and a second position. At least one driver unit activates the actuator and a control unit operates the driver unit. At least one air mass measuring device measures an air mass flowing through the valve. The control unit processes an output signal of the air mass measuring device. Valves, valve arrangements, seat comfort systems, and methods all use such circuit arrangements.

Actuation systems and methods are disclosed. An apparatus includes a system including a flow cell receptacle and a valve drive assembly including a shape memory alloy actuator including a pair of shape memory alloy wires and a flow cell disposable within the flow cell receptacle and having a membrane valve. The system actuates the membrane valve, via the shape memory alloy actuator, by causing a voltage to be applied to a first one of the shape memory alloy wires and the system not applying the voltage to a second one of the shape memory alloy wires.

An actuator assembly comprises a support structure (6), a movable part (5) movable relative to the support structure, at least one shape memory alloy (SMA) wire (2) connected between the support structure and the movable part via wire attach components and arranged, on contraction, to drive movement of the movable part and a control circuit configured to apply drive signals to the at least one SMA wire so as to drive movement of the movable part relative to the support structure between predetermined positions in a repeated pattern; wherein the length of the at least one SMA wire extending between respective wire attach components is less than 5 mm.