Cylindrical accuracy control based on stochastic modeling and forecasting compensation

Abstract

A new compensatory control strategy has been developed for improving the form accuracy in realtime condition. This scheme is based on obtaining an error model of the tool error measured in-process then forecasting the error at the cutting point to compensate for it with the appropriate compensatory action. This approach is a combination of in-process gaging, stochastic modeling based on recursive parameter estimation, forecasting compensation with minimum variance, and real-time compensatory action. In order to demonstrate the feasibility of the proposed approach, a physical compensatory control system has been developed and implemented for the purpose of on-line control of cylindricity in boring operations. Basically, the overall control system involves a closed-loop system and consists of an in-process laser-based cylindricity' measurement system, microcomputer and precise piezoelectric actuator systems. The effectiveness of this proposed strategy was confirmed through on-line cutting experiment.