Fault Diagnosis Technology And Software Design Of Rolling Bearing Based On Vibrational Resonance

Rotating machinery is an important component in mechanical equipment,and rolling bearings are important parts commonly used in rotating machinery.Almost all rotating machines have rolling bearings.It seems not complicated of the rolling bearings structure,while its role is irreplaceable.Especially when the rolling bearings are fault,their importance will become more prominent.It will not only have a major impact on the normal operation of the machine,but also cause an extremely serious safety accident in severe cases.In recent years,the fault diagnosis method of rolling bearing based on stochastic resonance has been widely studied.Although this method can use the energy of noise to enhance the weak fault characteristics of rolling bearings,its requirements on noise intensity are strict.If the noise intensity is too high,the effect of the classical stochastic resonance may be poor,or the fault information of the bearing may not be extracted at all.In addition,the noise is not easy to control.It can only be increased but it is difficult to be reduced.Therefore,based on the theory of vibrational resonance,several new methods for the fault diagnosis of rolling bearings are proposed in this paper.Moreover,based on this method,two kinds of bearing fault diagnosis software are designed.The specific contents of this paper are as follows:(1)A fault diagnosis method of rolling bearing only based on the vibrational resonance is introduced.The cosine signal is taken as an example in the classical firstorder overdamped bistable system.Through theoretical deduction,it is proved that the vibrational resonance method can be used to enhance weak signal in theory.Furthermore,the approximate relationship between the system parameters of the vibrational resonance is obtained.The method of general scale transformation is used to process the bearing simulation signal and experimental signal,so that it can meet the requirements of classical vibrational resonance for low frequency.Then the response amplitude is taken as the index to find out the best system parameters.Finally,the signal is processed by the vibrational resonance.The results show that the weak fault feature information of the bearing can be enhanced only by the vibration resonance method.Besides,the output frequency spectrum of the system is more obvious than the stochastic resonance output frequency spectrum.That means the vibrational resonance method can be used in the rolling bearing fault diagnosis.(2)An adaptive vibrational resonance method based on the improved response amplitude index is proposed to extract weak fault features of bearings.In vibrational resonance,the classical response amplitude or response amplitude gain index needs to know the accurate characteristic frequency in advance,which is often not practical in practice.Therefore,an improved response amplitude is introduced based on the traditional response amplitude index.The improved response amplitude index,which does not need to know the accurate characteristic spectrum in advance,can also achieve good results.In addition,the intelligent optimization algorithm is introduced to adaptively optimize the relevant parameters in the vibrational resonance process,which greatly improves the efficiency of rolling bearing fault diagnosis.(3)Based on the improved signal-to-noise ratio(SNR),the cascade adaptive vibrational resonance is used to extract the weak bearing fault characteristics under the noisy background.Since the response amplitude or response amplitude gain index is sensitive to noise,it is only suitable for noiseless or weak noise background conditions.In addition,the traditional SNR index also needs to know the characteristic frequency in advance.Sometimes,it is difficult to achieve the expected effect under the background of strong noise based the traditional SNR.Therefore,a cascade adaptive vibrational resonance based on improved SNR is proposed.This method does not need to know the characteristic frequency in advance and can adapt to strong background noise.(4)Based on the rolling bearing fault diagnosis method proposed in this paper,two kinds of rolling bearing fault diagnosis software based on different diagnosis methods are designed.MATLAB GUI is used to realize the bearing fault feature extraction by the adaptive vibrational resonance based on improved response amplitude index.The mixed programming of LabVIEW and MATLAB is used to realize the bearing fault feature extraction by cascade adaptive vibrational resonance based on improved SNR index.