Background: Micro-positioning platform is a device with high accuracy of positioning and a certain range of motion. Accuracy of the micro-positioning mechanism is ensured by using a flexible hinge to replace the traditional motion pair.
Objective: A two-dimensional micro-positioning platform is proposed in this study. It is necessary to find out how the geometric parameters affect the output displacement of the amplification structure component. Thus, this paper aims to build up the relation model of stiffness and geometric parameters.
Method: A novel method for building the relational model of parameters and output displacement is introduced on the basis of the superposition principle of small deformation and the principle of deflection. Firstly, the amplification structure is divided into different units according to the section shape and force. Secondly, the parametric model of integral deflection curve of the amplification structure is solved. The method is based on the flexibility matrix of the flexible hinge unit and the differential equation of the deflection curve of the rectangular unit. Finally, the parametric model of output displacement is established by using the integral deflection curve equation and geometric relationship between adjacent deformations of the compliant structure.
Result: It is shown that the output displacements by analysis method are close to the results achieved by the ANSYS software, with a maximal difference of 15.3%. The reason is that the integral deflection curve is not smooth at some special points, which is verified by finite element analysis.
Keywords: Micro-positioning platform, compliant mechanisms, flexibility matrix, deflection curve, finite element analysis, integration method.