A Novel Motion Stage Design By Reducing Disturbance Bandwidth Of Adrc For Higher Performance

Linear motion stages are widely used in high-speed precision engineering systems, such as electronics manufacturing and laser processing. Since the friction in these systems is a nonlinear high-frequency disturbance, the widely used friction compensation-based methods have a limit effect on the repeatability and accuracy which only reach the micron level. For higher accuracy and lower costs, this paper proposes a novel motion stage design method to solve the problem of friction disturbance and reduce the cost of the observer. The proposed design employs a rigid-flexible combined structural to reduce the disturbance bandwidth, so that the nonlinear high-frequency friction disturbance can be converted into the low-frequency elastic deformation disturbance, which can be easily tackled by compensation control. When the elastic deformation is presented on the stage, the influence of elastic stiffness on positioning accuracy and efficiency is studied. Proportional - integral - derivative (MD) controller and linear extended state observer (ESO) based active disturbance reject controller (ADRC) are carried out on the conventional and new designed motion stages while the control parameters can be tuned by bandwidth. Experimental results show that the maximum amplitude and settling time are reduced by 96.23% and 93.76%. respectively, compared to the conventional stage.