Analysis of Reversible Shape Changing Smart Structure using Shape Memory Alloys

This paper describes a study of smart structure composed of Ti-Ni shape memory alloys (SMA) and elastic materials. SMA is one of the effective materials which posses actuator function for start structure. However, in the conventional application of SMA, its shape change is non-reversible. Under certain conditions, SMA can show two-way shape memory effect (SME). But conventional two-way SMA is not used for smart structure because stability of the effect and strength of generated force is not sufficient. Composing SMA with elastic materials, the structures can response reversibly depending on temperature. In this paper, ring-shape type, which contains CFRP as the elastic materials, is investigated. Analytical models of reversible shape change and generated forces are led based on beam theory. The validity of the models is shown by comparison with experimental results.