Development of rotary-type electrostatic motor for MEMS microrobot

Recently, many researchers have expected millimeter-sized microrobots to work in narrow spaces. However, it is challenging to integrate the actuators, controllers, sensors, and energy sources into millimeter-sized microrobots. A small actuator with low power consumption is required to realize millimeter-sized microrobots. Previously, the authors developed a new linear electrostatic motor for microrobots. However, most microrobots rely on rotary actuators to expand their application scenarios and enhance adaptability. In this paper, the authors designed and developed a rotary-type electrostatic motor to provide a low-power drive solution for microrobots to address the limitations of linear motors and broaden their range of applications. Through experimentation, we identified an issue with reverse rotation in the electrostatic motor and analyzed its causes. To address the reverse-rotation issue, we proposed improvements, including optimizing the electrode structure and adjusting the drive waveform, which significantly enhanced the stability of forward rotation. The author plans to refine the motor's design further and integrate it into a microrobot system.