Integrated error correction system for machine performance improvement

An integrated error correction method using a feature-based analysis technique for improving the accuracy of CNC machines is presented. The method described in this paper emphasizes the integration of the process-intermittent gauging and analysis techniques with information from pre-process characterization and post-process inspection. The proposed method utilizes the information from pre-process characterization, post-process and process-intermittent inspection to improve machine performance automatically. Algorithms are derived for analyzing the post-process and process-intermittent inspection data to decouple process related error and machine error and then identify residual systematic errors. A feature-based analysis technique is developed to relate the dimensional errors of manufactured features to the systematic machine tool errors. Inverse kinematics and statistical methods are used to identify and characterize the contribution of each residual error component on imperfect features. A recursive tuning algorithm is also developed for fine tuning the error model. As the residual errors are continuously identified and the error model is iteratively fine tuned, the machine performance can be continuously improved for precision manufacturing.