Numerical and experimental analysis of the discrete workspace of a prestressed planar mechanism driven by six SMA wires

Abstract:
This paper deals with the workspace of a multi-antagonistic prestressed planar mechanism driven by six shape memory alloy (SMA) wires. The mechanism is organized in a ternary rotational symmetry enabling a same initial prestressed state in all the wires before applying a thermal activation sequence. The SMA wires can be activated individually, one or more at a time. The workspace is generated by their binary thermal actuation considering either the ambient temperature or a given higher temperature. The resulting discrete workspace that results from this binary activation is created from a finite element calculation software, namely Ansys Mechanical APDL. The objective of the model is to study the influence of the thermal actuation history on the discrete workspace. An experimental example is also presented.