Soft SU-8 Thermal Bimorph Actuators with Large Out-of-Plane Deflection

Thermal actuators are useful for precise and reliable control in various applications such as flow control, MEMS, robotics, and biology. However, existing actuators often suffer from large power consumption, slow response, and limited scalability, which limits their application particularly in underwater systems. Herein, we present the design and fabrication of SU-8 based thermal bimorph actuators having fast response and large out-of-plane deflection at low power levels, making them an ideal candidate for underwater applications. The time response and deflection of the thermal actuators were optimized by carefully tailoring the actuator geometry. We have verified the effectiveness of proposed actuators via computational and experimental results, which indicate that more than 60 mu m out-of-plane deflection could be obtained at around 35 mW input power, with actuation time as low as 200 ms.