Error analysis and compensation in machining thin-walled workpieces based on the inverse reconstruction model

摘要

At present, the error control process of the complex thin-walled workpiece mainly adopts the error suppression and error elimination; the effectiveness of error control depends on the cognition of the process designer about machine accuracy and the error-generating mechanism. This paper proposes a new compensation method to control errors in machining thin-walled workpieces based on the inverse reconstruction model. In this method, the thin-walled workpiece is represented by discrete point cloud (DPC) for error analysis; according to the unified error prediction model, the DPC positions can be obtained companying with the machining errors. Then the new DPC is reconstructed into the workpiece model used inverse reconstruction model. At the same time, a fairing algorithm is developed to deal with the smoothing problem of DPC. So, the new workpiece model is used instead of the original for processing. By this method, the machining precision and surface quality of thin-walled workpieces are ensured. In addition, a case study is presented to demonstrate the effectiveness of the method.