Design Optimization of Flexure Hinges Profile Using FEM and Experimental Verification in Piezoelectric Actuators

In this paper, flexure hinges as the main part of the actuators frame are studied considering different profiles of flexure hinges and effective design parameters to introduce the best profile of the hinge based on the application that is needed. For this purpose five different profiles (right circular, elliptical, corner-filleted, hyperbolic and parabolic) of flexure hinges have been considered and further studies have been carried out on flexure hinges based on some parameters such as accuracy, flexibility and the maximum stress in the hinge. The amount of flexibility of the hinge determined based on strain energy, accuracy of hinge (amount of deviation from actual hinge) and stresses in hinge is achieved invoking FEM analysis, we compare different profiles used in flexure hinges and the behavior of accuracy is studied with deflection variation. Different flexure hinge profiles are used in a sample mechanism and amplification factor, natural frequency and accuracy of results are compared with FEM results. In order to verify the obtained results, the sample mechanism with corner-filleted flexure hinge with the fillet radius of 0.1 mm is manufactured and the FEM results is verified with measured displacement of this sample frame.