Smart motion control by phase-coupled shape memory composites

This contribution describes a new functional principle for the motion of walking robots by means of shape memory composites. It illustrates the phase-coupled motion of actuator components with different shape memory alloys allowing wave-like or inch-worm behavior, respectively. The thermo-mechanical properties of the corresponding thin film composites with Ti(NiCu) and (TiHf)Ni alloys are discussed with the focus on their hysteresis. The shape memory effect of the actuators is characterized and samples are performed to prove their capabilities. The contribution also presents a bistable shape memory composite in which a PMMA polymer fixes the bending states of the metallic composite to reduce the energy consumption.