As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spin...As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spindle axis do not coincide with each other due to wheel settings,machining errors and so on.This could result in the generation of wheel runout,which may reduce the machining surface's quality.In this paper,combining this phenomenon,an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory.After that,the accuracy of this method is verified.Two experiments are carried out on a 5-axis machining center.The artificial runout is set up and calculated utilizing the least square method.Finally,using the presented method,two examples with and without runout are introduced to illustrate the validation of the proposed model.The error due to the runout effect is also analyzed.展开更多
A new quadrature sampling technique for arbitrary bandpass signal within baseband sampling rate is presented. The input bandpass signal whose carrier frequency lies in the A/D baseband sampling rate is first decimated...A new quadrature sampling technique for arbitrary bandpass signal within baseband sampling rate is presented. The input bandpass signal whose carrier frequency lies in the A/D baseband sampling rate is first decimated by factor 2 and modulated by (- 1)n, and then is interpolated by a linear phase FIR all-pass filter, finally the modulated complex envelope of bandpass signal can be produced.展开更多
基金supported by the National Natural Science Foundation of China(No.51605147)National Science Fund for Distinguished Young Scholars of Henan Polytechnic University(J2019-2)Young Backbone Project of Henan Polytechnic University(No.2018XQG-05)。
文摘As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spindle axis do not coincide with each other due to wheel settings,machining errors and so on.This could result in the generation of wheel runout,which may reduce the machining surface's quality.In this paper,combining this phenomenon,an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory.After that,the accuracy of this method is verified.Two experiments are carried out on a 5-axis machining center.The artificial runout is set up and calculated utilizing the least square method.Finally,using the presented method,two examples with and without runout are introduced to illustrate the validation of the proposed model.The error due to the runout effect is also analyzed.
文摘A new quadrature sampling technique for arbitrary bandpass signal within baseband sampling rate is presented. The input bandpass signal whose carrier frequency lies in the A/D baseband sampling rate is first decimated by factor 2 and modulated by (- 1)n, and then is interpolated by a linear phase FIR all-pass filter, finally the modulated complex envelope of bandpass signal can be produced.
