Synthesis and Characterization of Hybrid Actuator Based on Polypyrrole and SMA

This paper presents initial investigation on a hybrid artificial muscle actuator combining two actuation technologies, based on conductive polymers and shape memory alloys (SMAs). Polypyrrole is used as the conductive polymer muscle and nickel-titanium as shape memory alloy to make the composite muscle system. Depending on the geometry of the actuator, doped polypyrrole exhibits large strain, consuming less voltage and current; whereas shape memory alloy generates large stress (force), consuming high power (high current). Helically wound coil structure was chosen as the shape of the composite actuator in this study. The polypyrrole is synthesized on the surface of the Ni-Ti shape memory alloy wire, wound around a core gold coated polylactide fiber (PLA). Preliminary results on the performance and synthesis conditions of the composite actuator will be presented for various applications under different conditions.