Shape memory alloy actuation apparatus

A shape memory alloy actuation apparatus for moving a movable element relative to a support structure, the shape memory alloy actuation apparatus comprising:

• a support structure;
• a movable element supported on the support structure in a manner allowing movement of the movable element relative to the support structure in any direction in a plane;
• and
• four shape memory alloy actuator wires, each shape memory alloy actuator wire being connected at its ends to one of the support structure and the movable element and being hooked over a respective connector connected to the other of the of the support structure and the movable element, a first pair of the shape memory alloy actuator wires being arranged, on contraction, to drive movement of the movable element relative to the support structure, through the respective connectors, in opposite directions along a first axis in said plane, a second pair of the shape memory alloy actuator wires being arranged, on contraction, to drive movement of the movable element relative to the support structure, through the respective connectors, in opposite directions along a second axis in said plane transverse to said first axis,
• wherein each connector is a resilient member that is compliant in a direction in said plane laterally to the directions in which the respective shape memory alloy actuator wire drives movement of the movable element relative to support structure.