The Error Fluctuation Evaluation for Key Machining Form Feature of High-Value Difficult-to-Cut Part

To analyze the phenomenon of huge difference of performance quality machined by same equipment and machining procedure, an error fluctuation evaluation method is proposed. A formalized error propagation equation is established to model the error propagation relationship between quality characteristic and each process error based on machining error propagation network (MEPN). Based on this, two sensitivity analysis indices are defined to indicate the interactive effects of each process error on the quality. On the basis of real-time machining condition monitoring and in-process quality measuring, the Support Vector Regression (SVR) is introduced to solve the sensitivity analysis index of the parts in a same batch. Further, the error fluctuation coefficient is proposed to indicate the fluctuation of key Machining Form Feature (MFFs) and further evaluate the stability of Multistage Machining Processes (MMP). Finally, a deep-hole machining process of aircraft landing gear part is used to verify the proposed method.