A SYSTEMATIC-APPROACH TO ENHANCE MACHINE-TOOL ACCURACY FOR PRECISION MANUFACTURING

As competitive pressures demand higher levels of productivity and auto mation, accuracy and reliability of products become increasingly impor tant. Innovations in manufacturing technology also are driven by deman ds to shorten production cycle time and to maintain a consistently hig h level of product quality in an advanced manufacturing environment. I nnovative and cost-effective methods must be developed to advance prec ision manufacturing technologies to compete in the global economy. In this paper, a systematic approach is presented to advance the accuracy and functionality of multi-axis machines for precision manufacturing. Four major steps are introduced. First, a method is presented for rap id characterizing of the accuracy of multi-axis machines. Detailed der ivation of a generalized error model is given. Second, a method is dis cussed on the feasible applications of on-machine sensing and analysis . The information obtained from on-machine sensing process is used wit h the information collected from post-process inspection to improve th e machine performance. Third, a method is presented for utilizing post -process inspection and innovative data analysis techniques to decoupl e the effects of process- and machine-related errors. Finally, an adap tive error correction system is outlined for iterative identification of the residual error and the fine-tuning of the error model for more accurate error modeling and compensation. (C) 1997 Published by Elsevi er Science Ltd.