Power Electronics Design for Insect-Scale Flapping-Wing Robot With High Voltage Integrated Circuits

Abstract

The RoboBee is an insect-scale flapping-wing robot that is useful for a wide range of tasks, in- cluding exploration, environmental monitoring, as well as search and rescue. Recent advances in mechanical design, fabrication, and control enable this robotic insect to hover and maneuver while tethered to an external bench top amplifier. To achieve full autonomy, this work addresses the key challenge in designing a power electronics unit that generates the necessary excitation signals to drive the piezoelectric actuators, and meets the stringent weight limit of the robot. Upon meeting the functional and weight requirement, we also design for low power to optimize for flying time. In this thesis, we present two designs both employing high voltage LDMOS integrated circuits. The first design provides two high voltage driving signals tailored to two bimorph actuators in a simultaneous drive configuration. It meets the weight constraint at a cost of higher power consump- tion than that of alternative designs. The more recent design shifts to an alternating drive config- uration, and implements three power saving features to optimize for both power and weight.This design also uses drive stage circuits with a novel high-side gate driver to save chip area and further reduce its weight. Finally, we model the power consumption of these designs to make recommendation on multi-layers actuators for future RoboBee designs.