Development and analysis of a bridge-lever-type displacement amplifier based on hybrid flexure hinges

Bridge-type mechanism is one of the most widely used displacement amplifiers in micro scale applications due to its compact and symmetrical structure. However, a drawback of the bridge-type mechanism that restricts its further applications is the limited amplification ratio. To solve this problem, a bridge-lever-type displacement amplifier is developed and analyzed in this paper. Compared with the conventional design, the proposed amplifier not only maintains a compact and symmetrical structure, but also features a high amplification ratio and high load capacity. To reduce the displacement loss of the amplifier and enhance its load capacity, the hybrid flexure hinges are employed in the novel design. Furthermore, the kineto-static model based on the compliance matrix method and the dynamic model based on Lagrangian method are established to analyze the bridge-lever-type amplifier. Finally, a prototype is fabricated whose amplification ratio is approximately 48 and 34 in the case of zero load and 30 N load respectively, which is confirmed by FEA simulation and experimental study.