Development of a Compliant Four-bar Motion Amplification Mechanism Using Piezo Actuator

Abstract

Compliant mechanisms are the key component of the precision equipments. The mechanism composed by piezo actuator and compliant amplification mechanism can satisfyingly meet the demands of precision equipments for high resolution and larger stroke. This paper researched the displacement amplification and hysteresis of parallel four-bar amplification mechanism using piezo actuator. Firstly, the Preisach interpolation surface was established according to the voltage turning point at the hysteresis curve and Preisach function, and successfully realized the arbitrarily sequence output displacement of piezo actuator. Then the displacement amplification was analyzed by employing the material bending theory. The analysis results of theory and finite element model (FEM) proved that the amplification ratio of parallel four-bar mechanism is only related to the position of driving point, and the guiding beam displacement is linear with the driving point input. Finally, the calculation model of compliant amplification mechanism was established combine the compliant mechanism theory with Preisach interpolation surface. The experiment shows that the calculation model can effectively improve the output displacement accurate of the amplification mechanism and can realize arbitrarily sequence output displacement using the Preisach interpolation surface. Keywords; Piezo Actuator, Parallel Four-Bar Mechanism, Amplification Mechanism