Design of a new SMA micro-actuator

In this study, a new type of micro-actuator based on silica gel rod with embedded off-axis SMA wires was presented. The 3D formulation was presented. Using the 3D formulation and continuity theory of rod-wire interface, the equilibrium equations for SMA wires are obtained. By this equation, the forces and moments of this micro-actuator is yielded in theoretical predictions. To verify these formulations, we first use the finite element method to simulate and analyze. And then, a SMA test stand was established and property experiments were conducted. All results show these equations are correct. The experiments were conducted and the relationship between input voltage and output power of this micro-actuator was obtained.