A high-voltage power electronics unit for flying insect robots that can modulate wing thrust

Abstract

Flapping-wing insect-scale robots (<500 mg) offer enormous potential advantages over larger robots in applications such as agricultural support, environmental monitoring, and exploration of hazardous locations or extra-terrestrial space. Scaling laws that confer advantages to smaller robots, such as reduced materials cost and lower power requirements, also pose miniaturization challenges. Here we address the challenge of supplying a high voltage, oscillating signal to piezoelectric actuators that can be modulated to vary wing thrust. We present a system capable of modulating thrust for the generation of forces and torques required for control of flapping-wing insect sized robots. The power electronics unit with boost converter and two drivers is 90 mg including optional 15 mg output storage capacitor (not including 8 mg MCU). The boost converter operates at 30–40% efficiency at 240 V output under driver load and supplied with 7 V, and the driver produces sinusoidal wing flapping signals at typical operating output voltages of 160–220 V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pp</inf> with <14% total harmonic distortion. The system can linearly modulate measured thrust over 70% of the tested amplitude range from 40–200 V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pp</inf> . The thrust modulation reported here is necessary to realize controlled flight using on-board power systems, instead of externally provided signals via a wire tether.