Numerical Modelling of the Activation Behaviour of SMA‐Actuator Wires – Application in an Innovative Drive System

The activation behaviour of Shape‐Memory‐Alloy actuators (SMA) (and more specifically their dynamic properties) is characterised by the rate of heating and cooling. This paper deals with the development, the validation and the application of a numerical model that simulates the activation behaviour of straight SMA‐wires depending on their geometry, the loading condition and an arbitrary time variant heating current. Taking changing thermal, electrical, geometric and mechanical boundary conditions into consideration, the model supports the design layout process of technical solutions with SMA‐wires. Based on this numerical model for dimensioning and conditioning of SMA‐actuators, an innovative rotatory drive system powered by straight SMA‐wires is presented.