In order to reduce the machining errors of free-form surface parts and improve the machining accuracy,an Ensemble Empirical Mode Decomposition (EEMD) method combined with surface reconstruction is proposed to decompose and compensate the machining errors.EEMD is used to decompose the machining errors after the first cutting detected by the machine,and several Intrinsic Mode Functions (IMFs) are obtained.According to the characteristics of systematic er-rors,the IMFs component containing systematic errors in machining errors is screened by setting the threshold of correlation coefficient,that is,the decomposed systematic errors.According to the system error,a new machining surface is obtained by surface reconstruction method,and a new NC code is generated according to it,and the machining is carried out again to compensate the system error.Through the simulation analysis of EEMD decomposition machining error,it can be concluded that EEMD has a relatively ideal machining error decomposition ability.The machining example results show that the maxi-mum absolute machining error decreases from 0.0632mm to 0.0139mm and the average absolute machining error decreases from 0.0491mm to 0.0052mm when the machining error is compensated by the method proposed in this paper.The machi-ning accuracy is increased by 89.4％.The effectiveness of this method in machining error compensation of free-form surface parts is proved.
维普
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