Analysis Of Chaotic Characteristics Of Acoustic Emission Signals During Grinding Wheel Blunting

Grinding is an important finishing method and a very complex process.The state of the grinding wheel plays a decisive role in the grinding performance and processing quality.It is a key process to ensure the quality of grinding process that judging of the state of the grinding wheel accurate and dressing timely.With the development of modern automated processing technology,higher requirements are put forward for the identification of the grinding wheel status.Acoustic Emission Signals(AES)are associated with the grinding process and are an important signal source for identifying the status of the grinding wheel.It is being a increasing important issue that how to identify the state of the grinding wheel from the AES in the complex grinding process in recent years.In order to study the nonlinear characteristics of AES in grinding process,the research progress of acoustic emission technology,AES in the process of grinding wheel blunting and the chaotic characteristics of AES are summarized in detail,the principle of acoustic emission detection technology is introduced,and the analysis and processing methods of AES are summarized.It has been design for the experimental scheme of acoustic emission detection in grinding process of grinding wheel in this paper.Based on the parameter analysis and waveform analysis,the characteristic parameters and spectrum characteristics of the grinding wheel are analyzed,and the chaotic theory is used to analyze the AES during grinding wheel blunt process,the chaotic characteristics of the AES of the grinding wheel blunting are studied,and basic work is attempted to characterize the nonlinear characteristics of the grinding wheel blunting process.The main research works and achievements in this paper are as follows:(1)Acoustic emission instrument was used to detect the grinding process of grinding wheel,the AES of six different grinding depths were collected,and the characteristic parameters such as RMS voltage,amplitude,energy and count were recorded.(2)The AES of grinding wheel blunt process were collected by wavelet threshold noise reduction processing.The characteristics of AES of grinding wheel blunt process were studied by parameter analysis and waveform analysis.(3)The algorithms of each chaotic characteristic parameter are verified through the Lorenz system.Based on the chaos theory,the phase space reconstruction of the AES during the grinding wheel blunting process was carried out,and the phase space trajectory diagram was analyzed,and the three chaos of the largest Lyapunov exponent,the correlation dimension and the Kolmogorov entropy of the AES during the grinding wheel blunting process were extracted.The results show that the AES of the grinding wheel at different wear stages have chaotic characteristics;and the largest Lyapunov exponent,correlation dimension and Kolmogorov entropy of the AES correspond to the wear stage of the grinding wheel.These three chaotic characteristics can be used to characterize the different wear stages of the grinding wheel.