Multi-stable SMA actuator comprising two shape memory alloy wires (1, 2) in antagonistic configuration that allow to define multiple stable positions of a movable element (12), said positions being maintained by movable stoppers to lock the movable element, that do not require power and are disengaged by the shape memory alloy wires (1, 2) upon actuation thereof.

An inflatable structure includes an inflatable membrane with an outer surface, and a skin with a textured space-filling Turing pattern disposed on the outer surface of the inflatable membrane. A variable stiffness filament is coupled to the inflatable structure and the variable stiffness filament has a first stiffness at a first temperature and a second stiffness different than the first stiffness at a second temperature different than the first temperature. An electrical energy source is included and in electrical communication with the variable stiffness filament, and the electrical energy source is configured to apply Joule heating to and increase a temperature of the variable stiffness filament from the first temperature to the second temperature such variable stiffness actively controls a stiffness of the inflatable structure.

A shape memory alloy (SMA) actuator comprising: a support structure (10); a moveable part (20) movable relative to In the support structure; plural SMA components (30) connecting the support structure and the movable part, the SMA components are operable to controllably change the position and/or orientation of the moveable part in two or more degrees of freedom; a controller (12) for controlling the operation of the SMA components in a first operating mode during normal operation and a second operating mode in response to an event; and means configured to, during the second operating mode, maintain at least partial control of the moveable part with a subset of the plural SMA components.

An optical mechanism is provided. The optical mechanism includes an immovable part, a movable part, a drive assembly, and a guidance assembly. The movable part is connected to an optical element. The movable part is movable relative to the immovable part. The drive assembly drives the movable part to move relative to the immovable part. The guidance assembly guides the movable part to move along a first axis.

SMA actuators and related methods are described. One embodiment of an actuator includes a base; a plurality of buckle arms; and at least a first shape memory alloy wire coupled with a pair of buckle arms of the plurality of buckle arms. Another embodiment of an actuator includes a base and at least one bimorph actuator including a shape memory alloy material. The bimorph actuator attached to the base.

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.

A rigidity variable apparatus includes: one or a plurality of coil units including a spiral-shaped coil portion in which a plurality of SMA element wires made of a shape-memory alloy are wound around an axis at a first pitch in a state where the SMA element wires are overlapped with each other in a predetermined axis direction, each of the SMA element wires memorizing a spiral shape with a pitch narrower than the first pitch, one of the plurality of SMA element wires starting to deform to the memorized spiral shape with a predetermined pitch when at a predetermined temperature or higher, another of the plurality of SMA element wires starting to deform to the spiral shape with a different pitch; and an electrothennal heater configured to heat the coil portion.

A shape memory alloy actuator assembly comprises a first part, including a surface, a second part which moves relative to the first part across the surface and a resilient biasing element that biases the second part into contact with the first part so as to generate frictional forces therebetween for retaining the second part on the surface. At least one shape memory alloy actuator wire is connected between the first part and the second part and arranged to, on contraction thereof, apply a force to the second part with a component parallel to the surface that drives movement of the second part relative to the first part across the surface. Thus, the second part is retained on the surface when no power is applied to the shape memory alloy wire, and movement is achieved when power is applied.

The present disclosure relates to a reduced friction torsion component system that makes use of a first frame portion adapted to be coupled to, or integrally formed with, a first object, and forming a first bore, and a second frame portion adapted to be coupled to, or integrally formed with, a second object, and forming a second bore. The two bores are axially aligned and receive at least one elongated hinge component. The elongated hinge component operates to both couple the first and second frame portions together for pivoting movement relative to one another, and also provides a torsional biasing force to enable pivotal deployment from a first position to a second position of one of the first or second frame portions.

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.