A BISTABLE MICRO-ACTUATOR WITH STROKE REDUCING STRUCTURE

This paper presents a monolithic bistable micro-actuator with stroke reducing structure. A single pre-shaped beam was chosen as the bistable element. To constraint the rotation of the central point of the beam and get more precise output, two kinds of stroke reducing structures were designed and monolithically integrated into the actuator. The first design is purely based on flexible hinges. To decrease the dimension of the stroke reducing structure and maintain the output at the same order, a second hybrid stroke reducing structure integrated micro-actuator using flexible hinges and deflected beams was designed. Both devices were fabricated by laser machining of medium density fiberboard material. Outputs of the bistable micro-actuator before and after the reducing structure were measured by fiber optic distance sensor. The bistability was experimentally characterized. The output stroke before and after reduction for the first reducing structure are 2.38mm and 0.79gm. The outputs stroke before and after reduction for the second hybrid reducing structure are 2.38mm and 0.99 mu m.