Design, Fabrication, and Characterization of a Pneumatic Micro Actuator

Abstract

Compact high force linear displacement pneumatic microactuators are useful in several applications including robotic systems, surgical micro-grippers, micro mechanisms, and so on. This paper presents development of a general purpose bellow type microactuator using silicon as structural material with a low stiffness double parallelogram flexure guides for a planar bellow piston. Double flexure mechanism achieves frictionless guiding in a perfect straight line of the actuator. The proposed design is different as compared to similar other designs in the literature in that the new design proposes a flexure guide for piston. Moreover, it is integrated with comb drive for servo actuation and is five times smaller. The actuators are fabricated using standard SOIMUMPs process and are further characterized. Actuation pressure, displacement and blocking force are measured which further demonstrates their performance in comparison with simulation results. Finally, as an application example micro-flexural logic device viz. NOT gate, actuated using the micro-pneumatic actuator is presented.