Design,modelling and characterization of a 2-DOF precision positioning platform

Abstract

This paper presents the mechanical design, parameter optimization and experimental tests of a 2-degree-of-freedom (DOF) flexure-based precision positioning platform, which has great potential application in many scientific and engineering fields. During the mechanical design, the leaf parallelogram structures provide the functions of joint mechanisms and transmission mechanisms with excellent decoupling properties. The dynamic model of the developed positioning platform is established and analysed using pseudo rigid body model methodology. A particle swarm algorithm optimization approach is utilized to perform the parameter optimization and thus improve the static and dynamic characteristics of the positioning platform. The prototype of the developed 2-DOF positioning platform has been fabricated using a wire electric discharge machining technique. A number of experimental tests have been conducted to investigate the performance of the platform and verify the established models and optimization methodologies. The experimental results show that the platform has a workspace range in excess of 8.0×8.0 μm with a stiffness of 4.97 N/µm and first-order natural frequency of 231 Hz. The cross-axis coupling ratio is less than 0.6%, verifying the excellent decoupling performance.