Design and computational optimization of a flexure-based XY positioning platform using FEA-based response surface methodology

This paper presents the mechanical design and computational optimization for a flexure-based XY positioning platform that is capable of performing planar translational motion with two degrees of freedom in the-x and-y axes. During the mechanical design, the hybrid leaf spring and right circular hinges are adopted to increase the travel displacement and reduce the cross-axis coupling errors. These hybrid joints create the parallelogram structures which provide the functions of joint and transmission mechanisms with excellent decoupling properties. The statistics and dynamics of the mechanism are analyzed, and these analyses are validated with FEA and experimental results. A finite element analysis-based response surface methodology is utilized to solve the multi-objective optimization problems and thus the static and dynamic characteristics of the positioning platform are improved. The prototype is fabricated using a wire electric discharge machining technique. The experimentations are carried out to investigate the performance of the platform and verify the established performance characteristics and optimization methodologies. The experimental results reveal that the platform has a broad workspace range in excess of 125 μm × 125 μm with a first-order natural frequency of 740 Hz. The cross-axis coupling ratio is less than 0.6% verifying the excellent decoupling property.