SMA actuator assembly

Abstract

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.

Dependencies are inferred from the claim text.