A control method with considering error coupling in milling multi-feature thin-walled parts

Abstract

Multiple features of thin-walled parts have position-dependent and dimension association, which means that multi-feature machining errors can affect each other. They may be coupled in multiple processes. Therefore, multi-feature couple effect plays a significant impact on thin-walled parts machining process in some cases. The most existing error coupling analysis methods ignore the error influence between features. To overcome this problems, Multi-feature machining is investigated thoroughly, error coupling method is proposed to consider these effects in this paper. According to the influence mode of multi-feature machining, error coupling is decomposed into geometric interaction and machining interaction, and analyze individual influence mode. The geometric interaction is tolerance/datum interactions. The machining interaction is generated from machining operations. A method based on SDT (small displacement torsors) and transformation of the coordinate systems is employed and integrated to the comprehensive error model. Besides, a compensation method by adjusting the pose is proposed. Finally, a case study is performed to validate the proposed method.