Abstract: A shape memory alloy (SMA) actuator (100) for a camera assembly, comprising:—a support structure supporting an electronic component, wherein the electronic component is susceptible to interference caused by magnetic flux;—a moveable part moveable relative to the support structure; one or more SMA components (12) connected between the moveable part and the support structure, wherein the one or more SMA components are configured to, on contraction, drive movement of the movable part;—a first electrical path and a second electrical path defined between, and/or including, each of the one or more SMA components (12) and respective electrical terminals (3a); and wherein the first and second electrical paths of each of the one or more SMA components are configured to, at least in part, extend adjacently to and in parallel with each other, and enabling the electrical current in the respective paths to flow in opposite directions, so as to minimise combined magnetic flux from the first and second electrical paths into

Abstract: An actuation assembly comprising: a support structure; a movable element movable relative to the support structure, the movable element having a principal axis; and an actuator arrangement for driving movement of the movable element with respect to the support structure, wherein said movement includes rotational movement of the movable element about an axis which is perpendicular to said principal axis and does not pass through the centre of the movable element, and wherein said movement also includes translational movement of the movable element in a direction perpendicular to the principal axis. The actuation assembly may be used to perform optical image stabilisation or to improve the performance of a 3D sensing system.

Abstract: An SMA actuator (10) comprising SMA wires (31, 32) in which the wire arrangement is asymmetrical, allowing a greater range of motion from a rest position in a first direction than in a second direction, which may be opposite or orthogonal to the first direction. Where the directions are opposite, the angle between a principal axis and the wires providing motion in the first direction may be different from the angle between the principal axis and the wires providing motion in the second direction.

Abstract: An SMA actuation assembly comprising SMA actuator wires connected in tension between a support structure and a movable element is controlled to drive movement of the movable element with respect to the support structure by supplying drive signals to the SMA actuator wire. Target signals representing desired positions of the movable element are set, varying within a predetermined spatial envelope. Measures of resistance of the SMA actuator wires are derived and the power of the drive signals is controlled under closed loop control on the basis of the target signals and feedback signals obtained from the measures of resistance. Electrical characteristics of the SMA actuator wires are monitored and used to detect when a motion limit of the movement is reached. In response thereto, the spatial envelope is adjusted to restrict the movement to be within the detected motion limit.

Abstract: An SMA actuation assembly comprising SMA actuator wires connected in tension between a support structure and a movable element is controlled to drive movement of the movable element with respect to the support structure by supplying drive signals to the SMA actuator wire. Target signals representing desired positions of the movable element are set, varying within a predetermined spatial envelope. Measures of resistance of the SMA actuator wires are derived and the power of the drive signals is controlled under closed loop control on the basis of the target signals and feedback signals obtained from the measures of resistance. Electrical characteristics of the SMA actuator wires are monitored and used to detect when a motion limit of the movement is reached. In response thereto, the spatial envelope is adjusted to restrict the movement to be within the detected motion limit.