Driving high voltage piezoelectric actuators in microrobotic applications

Piezoelectric actuators have been used successfully to enable locomotion in aerial and ambulatory microrobotic platforms. However, the use of piezoelectric actuators presents two major challenges for power electronic design: generating high-voltage drive signals in systems typically powered by low-voltage energy sources, and recovering unused energy from the actuators. Due to these challenges, conventional drive circuits become too bulky or inefficient in low mass applications. This work describes electrical characteristics and drive requirements of low mass piezoelectric actuators, the design and optimization of suitable drive circuit topologies, aspects of the physical instantiation of these topologies, including the fabrication of extremely lightweight magnetic components, and a custom, ultra low power integrated circuit that implements control functionality for the drive circuits. The principles and building blocks presented here enable efficient high-voltage drive circuits that can satisfy the stringent weight and power requirements of microrobotic applications.