Mechanism Of Vibration Damping For Suspensions With Annular Vibration-Absorbing Structure With Time-Delay

The conventional suspension structure can hardly satisfy the demands of vehicle smoothness and handed stability at the same time,and the time-delay phenomenon is inevitable in the active control process.The application of time-delay feedback control in the system and the selection of reasonable control parameters can effectively reduce the vibration of the system.With the above problems in mind,this paper proposed a new suspension structure with an annular vibration-absorbing structure,applied the time-delay state feedback control technology to it,and successively proposed single time-delay feedback control,double time-delay feedback control under different control objects,and combined simulation based on Carsim/Simulink to study the effectiveness of the new suspension with time-delay feedback control on body vibration reduction.Firstly,a new suspension structure with an annular vibration-absorbing structure was proposed.The annular vibration-absorbing mass block in this new structure can absorb the vibration transmitted to the body by the wheels,thus reducing the vibration transmitted to the body.With suspension performance indexes as the optimization objective function,the optimum parameters of the annular vibration-absorbing structure were obtained.The conventional suspension and the new suspension were compared and analyzed in the time and frequency domains.The results showed that the new suspension significantly improved the body droop acceleration and tire dynamic displacement,and improved the ride comfort of the vehicle.Secondly,in 1/4 of the new suspension system with an annular vibration-absorbing structure,it is studied in single time-delay feedback control for different control objects respectively.By using the Routh-Hurwitz stability criterion,the characteristic root method and the stability switched method,the time-delay independent stability region,and the critical time-delay stability region of the system under different time-delay feedback control were analyzed.The system vibration response was solved by the fine integration method,and the optimal time-delay parameters are obtained when the objective function was minimized,with the suspension performance index as the optimization target.Then the differences in time-delay feedback under different control objects are compared from the time domain and frequency domain.The results showed that for different control objects,the time-delay feedback control can reduce the vibration of the body,but the effect of vibration reduction is general.Thirdly,two types of time-delay feedback control were introduced into a new suspension system with an annular vibration-absorbing structure,and a new suspension damped method with double time-delay feedback control was proposed,in which different road excitations were introduced into the objective function model to optimize the optimal parameters under double time-delay feedback control.The Routh-Hurwitz stability criterion and the frequency domain scanning method were combined to verify the stability of the double time-delay system under the optimal feedback control parameters.The new suspension system with an annular vibration-absorbing structure under double time-delay control was analyzed and compared with the new suspension system with the annular vibration-absorbing structure under different single time-delay control.The results showed that the new suspension system with an annular vibration-absorbing structure under double time-delay feedback control can significantly reduce the body vibration and improved the overall performance of the vehicle.Finally,by using Carsim/Simulink to establish a combined simulation platform,the3 D reconstruction of the random road surface,through the combined simulation model,to obtain the time domain simulation analyzed results of the performance evaluation indexes of the new suspension system under optimal time-delay feedback control,further verified the effectiveness of the new suspension under time-delay feedback control.In this paper,through the construction of different time-delay stated feedback control for the new suspension with an annular vibration-absorbing structure,analyzed the effect of time-delay stated feedback on body damped under different control objects and verified in the vehicle dynamics software,which provided a certain reference value for the researched in the field of vehicle vibration reduction.