High precision instrumentation and control

Abstract

This thesis focuses on the precision improvement in high precision system. First, a geometric error compensation method using displacement measurements only is proposed and the individual error components are estimated using radial basis function (RBF). Secondly, a thermal error compensation approach is proposed and two-dimensional RBF is designed to approximate the errors relating to both movement positions and operating temperatures. Thirdly, as measurement accuracy is critically important to achieve high precision control, an approach towards precision motion control with a selective fusion of multiple signal candidates is furnished using multiple sensors for the same measurement. Finally, for industrial application purpose, a micro-dispensing drop-on-demand system is investigated and both error compensation on the stage and the printed droplets are proposed and applied. The effectiveness of the proposed models and methods are verified in experiments.