Vibration Characteristic Analysis Of The Coupled System Of Omnidirectional Moving Wheelchair And Road

The market demand for electric wheelchairs is increasing gradually with the aging trend of our population becoming more and more severe.Ride comfort is one of the important indicators for assessing wheelchairs,and the dynamic performance of wheelchairs is an important factor.Poor dynamic performance will make the rider feel uncomfortable in psychologically and physiologically,causing "secondary injury" to the rider.Research on the current status of omnidirectional wheelchair and vehicle-road coupling dynamics,it is found that the research content mainly focuses on structural optimization and intelligent control,and the influence of vibration characteristics on the rider in the research process of omnidirectional Wheelchair based on Mecanum wheel is not considered.Otherwise,in the traditional vehicle-road system dynamics analysis,vehicle dynamics and road dynamics are often considered as two independent systems,but the vehicle and road are a whole system interact with each other and indivisible,and it can not reflect the real situation between the vehicle and the road.Therefore,this paper mainly studies the dynamics of omnidirectional wheelchair and road coupling system based on Mecanum wheel.In this paper,according to the actual situation of omni-directional wheelchair based on Mecanum wheels movement on the road surface.the wheelchair-road system is divided into three subsystems: “simplified wheelchair overall vibration model”,“contact model of Mecanum wheels with pavement” and “vibration model of rigid pavement structure”,and Fourier inverse transformation method is used to simulate the actual road irregularity.Considering the special structure of Mecanum wheel,the vibration equation of wheelchair-road coupling system is constructed by using the displacement coordination equation of wheelchair-road contact point and the equilibrium relation between wheelchair and road surface established on the basis of D’Alembert principle.The interaction between wheelchair and road,the dynamic response of coupling system and the comfort of electric wheelchair are studied theoretically.In the second place,under the condition that the four wheels of Macanum wheel are in the optimal layout form,the principle of its omnidirectional movement is analyzed.Last but not least,an omni-directional mobile experimental platform was built to verify the accuracy of numerical simulation through experiments.And a large number of statistical analysis is carried out on the experimental data.On the one hand,the correctness of theoretical model and the scientificity of experimental system design are verified by comparing the reliable experimental results with the theoretical results;on the other hand,the deficiencies of analytical model and the causes of errors are the influence of model parameters on the overall vibration characteristics of wheelchair.Through theoretical research and simulation analysis,this paper will further promoted the research work on the mechanism of omnidirectional wheelchair and road interaction system based on Mecanum wheel,and provide theoretical guidance for the optimization design of wheelchair safety and comfort and better control of wheelchair omnidirectional movement,which has important theoretical research and engineering application value.