Research On Non-stationary Vibration Characteristics Of All-Terrain Vehicle Based On VMD-Teager

As an important part of our modern automobile manufacturing products,with the rapid improvement of China’s economic level,more attention has been drawn to the research of construction vehicles.Due to the harsh working environment,it is often accompanied by noise and vibration.The vibration generated by the vehicle often damages the health of the human body and also affects the overall ride comfort.In order to solve the above problems,it is necessary to analyze the vibration signal of the vehicle to provide a theoretical basis for the subsequent improvement of comfort.In order to study the vibration characteristics of construction vehicles and provide a basis for the improvement of vehicle ride performance and comfort,this project is based on the National Natural Science Foundation Youth Fund Project: "Research on the dissipative mechanism and behavior characteristics of step-varying damping of viscoelastic buffer system"(51805347)and the project supported by China Postdoctoral Science Foundation: "vibration dissipating machine of non-contact quasi zero stiffness vibration isolation system"(2019M661058),the following research is carried out for a type of all terrain vehicle:By investigating the working environment of construction vehicles and the working characteristics of such vehicles,it is determined that the vibration signals generated by construction vehicles during their operation are mostly nonstationary vibration signals whose statistical characteristics in the time domain and frequency domain change over time.However,if the non-stationary signal is studied with the help of traditional stationary signal analysis methods,it is impossible to reveal its implicit laws.However,the use of time-frequency domain joint analysis can show the localized characteristics and full picture of nonstationary signals in the time and frequency domains.By studying the basic theories of variational modal decomposition and Teager energy operator demodulation,a new method of determining the number K of variational modal decomposition is proposed.In order to analyze the time-frequency of various kinds of measured nonstationary vibration data to study its vibration characteristics,a software for timefrequency analysis of nonstationary vibration signals is designed by using Matlab graphical user interface module,which integrates the functions of data processing,data preservation,time domain analysis,power spectral density analysis and timely frequency analysis.Due to the limited time,the software only completed version 1.0,but also greatly facilitated the processing and analysis of the subsequent non-stationary vibration data,and provided a tool for the vibration signal analysis of various engineering vehicles.