Millimeter-scale micro-robotic leg actuators are described that integrate thin-film lead zirconate titanate (PZT) piezoelectric actuation with compliant structures formed from parylene-C polymer. Models for out-of-plane rotation using piezoelectric cantilevers and in-plane rotation using high-aspect ratio polymer beams are discussed. Opportunities are highlighted for thin polymer films to aid in load-bearing, flexibility, and resilience of piezoelectric micro-robot appendages. A simple 5 mm × 2.4 mm × 0.15 mm hexapod robot prototype incorporating multiple actuators in each leg assembly is fabricated and tested within the silicon wafer in which it was built. Completed robot leg performance shows close agreement between modeled and tested static and dynamic characteristics, with potential benefits for future walking micro-robots from low power requirements relative to payload capacity and large amplitude motion at resonance.
Available at: http://works.bepress.com/minchul-shin/4/