LTV-FIR command prefiltering for vibration reduction of a flexure-jointed X-Y motion stage with payload variation

Abstract

This paper investigates the application of a linear-time-varying (LTV) command prefilter for vibration reduction in motion control of LTV systems. A model-based time-varying prefilter function is constructed that can be convolved with arbitrary command input signals to achieve residual vibration cancellation in a finite time. The prefilter is implemented on an experimental X-Y micro-positioning stage with a low-compliance flexure-jointed mechanism. Model coefficients within the LTV prefilter realization are varied in real-time according to measured platform position. As the dynamic model is also dependent on platform payload, a method is introduced to compensate for changes of payload mass based on the interpolation of model coefficients for extremum values. The results reveal that residual vibration can be cancelled effectively with settling time reduced from over 2 seconds to less than 0.4 seconds. Rapid point-to-point maneuvers over large travel distances, and with different known values of payload mass, can be achieved with high accuracy.