Rotational Morphing of a Low-Power Electrothermal Kirigami MEMS Actuator via Low-Cost PWM Heating

This paper reports the rotational morphing capability of a low-power electrothermal kirigami MEMS actuator driven by low-cost pulse-width modulation (PWM) heating, advancing the application of electrothermal MEMS actuators in multi-degree-of-freedom (multi-DoF) robotics. PWM-controlled voltages were applied to each of the actuator's four quadrant-based Joule heaters. By dynamically adjusting the duty cycles of the voltages applied to each heater, localized heating regions within the actuator were rotated, resulting in mechanical rotational morphing. The actuator exhibited continuous rotational motion while maintaining a tilting angular displacement of approximately 8°, with a power consumption of only 76mW.