Identification and Compensation of the Flexure-Induced Motion Error with a Voice Coil Motor

Abstract

Flexures are commonly used in various fields, including optics, microscopy, robotics, and precision engineering since they offer several advantages over traditional motion systems that employ mechanical bearings or sliding mechanisms such as high precision, minimal friction and hysteresis, lack of backlash, compact and lightweight, no lubrication and high stiffness. Flexure may experience cross-coupling effects, which occurs when motion along one axis affects motion along another axis due to mechanical interactions between the flexures. This can lead to unwanted motion errors of flexures or flexure-induced motion errors. This paper discusses identification and compensation of the flexure-induced motion error with a voice coil motor. Firstly, we built one DOF motion system supported by flexure and drove the motion system with a voice coil motor. Flexure-induced motion errors are then identified experimentally using single sine excitation. The single sine excitation can quantitively estimate the inclination angle of the flexure motion system, which makes cross-coupling error. Finally, a feedforward compensation method for the flexure-induced motion error with the voice coil motor is proposed and verified through experimentation.