20.9 An Autonomous and Lightweight Microactuator Driving System Using Flying Solid-State Batteries

Efficient high-voltage drive systems for electrostatic and piezoelectric actuators are crucial in small-scale electromechanical applications, but they significantly impact the overall system weight, especially in microrobotics [1]–[3]. These systems operate at low frequencies (10's Hz [2]) and require a significant voltage conversion ratio to generate high voltages (in the tens of volts [4]) from low-voltage sources like electrochemical batteries (3-to-5V), all while meeting stringent size and weight constraints (1's g [2]), and flight endurance (10's of min [31). Due to their primarily capacitive nature, these actuators demand mostly reactive power <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{C}_{\mathrm{x}}\mathrm{V}^{2}\mathrm{F})$</tex> in the 10's mW range [2] to efficiently drive dielectric materials <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{C}_{\mathrm{x}}$</tex> =1's to 100's nF [5]). Effective management of this reactive energy is essential for reducing power losses, which subsequently improves flight autonomy - a vital factor due to the limited energy storage in micro-scale flying devices [2].