Noise Source Location System Of Particle Packaging Machine Based On Microphone Array

The particle packaging machine makes a strong noise in operation,and its mechanical noise is the main noise source.The noise easily causes the worker’s discomfort,so that their labor force declined significantly.Therefore,the noise source location of the packaging machine is great significance.At present,most of the noise detection of the packaging machine uses random vibration analysis to locate the noise source,but its process is complex,For the more,it is difficult to popularize and apply it in practical engineering.This study uses a microphone array to locate the noise source of the packaging machine.The microphone array has the characteristics of small space.It can be considered to point measurement,and it has high flexibility.The positioning method is divided to two steps,Firstly,the sound signal of the packaging machine is collected.Secondly,the time delay method and signal processing technology are used to locate the noise in the packaging machine.Based on the time delay method,a 1/4 spherical microphone array is proposed to locate the sound source.The original signal is the TSP signal.In the processing of performing waveform shaping,the frequency response can be obtained by the deconvolution of excitation and measured signal.For random signal,this system uses the main frequency of the noise to preprocess.The system divides signal processing into three steps.Firstly,the signal is interpolated by zero-filling in the frequency domain.Secondly,four microphones with the higher correlation in the array are selected by using the cross-correlation function.And the time delay is calculated.Thirdly,the sound source position is calculated based on the spatial rectangular coordinate relation.Through the above steps,detection of the main noise source of the packaging machine can be realized.The study implements the experimental hardware system and the software system are programed by using C language.The experiments are conducted to verify the positioning accuracy of the system.In addition,the study uses camera calibration based on machine vision to mark the sound source location on a two-dimensional image.The location noise source is offline detected by collecting the signal of the particle packaging machine in the running state.The causes of the accuracy error are analyzed.