Employing cubic Bézier curve in design compliant bistable micromechanism

This article reports a new compliant bistable micromechanism (BM) with force output flexibility under a space constraint. The mechanism is jointless and save energy. The mechanism has four Bézier curved beams and a shuttle mass at its center. A cubic Bézier curve with four-point controls offers high flexibility for designing beam shapes of BMs that modify the maximum and minimum force in the same design space. The finite element method is applied to predict and investigate the bistable behavior. Compared to the conventional BMs with cosine curved beams and slanted straight beams, the BM with Bézier curved beam can be designed to have smaller switching forces under the same device area and thickness. The various Bézier profiles are designed with many nonlinear characteristic. Essential design paramters affect the nonlinear characteristic of BM are examined.