Study On Stability Analysis And Identification And Detection Of Chatter In Milling Process

As a widely used processing method,milling plays an important role in aviation and aerospace manufacturing.However,due to the selection of different processing parameters in milling,chatter problems will occur,which seriously affect the processing quality and processing efficiency of the workpiece.At present,for the problem of chatter in milling,the research work is mainly focused on the analysis of chatter stability in milling and chatter detection and monitoring.By predicting the stability lobe diagram,the processing parameters are reasonably selected to avoid the occurrence of chatter;the chatter detection and monitor can be better applied to the actual engineering field after considering the error of the stability analysis results,and the chatter information can be timely identification and early warning to adjust processing parameters in time.This paper focuses on the chatter problem in the milling process,and develops the following work from three aspects: milling force modeling and cutting force coefficient calibration,milling stability analysis,and chatter identification and detection:First,for the problem of accurate prediction of milling force,this paper considers the factor of nonlinear change of milling force coefficient with instantaneous uncut depth,establishes a nonlinear milling force model,and proposes a milling force coefficient identification based on instantaneous milling force and eccentric parameter calibration method.Experiments show that,compared with the classic linear model-based averaging method,the proposed nonlinear model-based averaging method and nonlinear model-based instantaneous identification method have better calculation accuracy and efficiency.Second,to study the stability of the milling process,a stability analysis method based on the compound Simpson formula is proposed.This method uses the compound Simpson formula to calculate the state transition matrix during the milling cycle,and uses Floquet stability analysis theory to analyze the state transition matrix to judge the milling stability.Third,considering the situation of the actual processing process,the chatter phenomenon in milling process cannot be completely avoided by the stability lobe diagram.Therefore,for the identification and detection of chatter,this paper proposes a milling chatter detection method based on morphological empirical wavelet transform.This method uses the energy entropy of the decomposed signal as the chatter monitoring index,which realizes the early identification and early warning of chatter and has good sensitivity.In this paper,the problem of chatter in milling is studied and analyzed in detail,such as the accurate prediction of milling force,the stability of milling process,and the identification and detection of chatter.The theoretical derivation is combined with simulation verification and experimental verification.The results of this paper have certain significance for the future research on milling dynamics.