The Design And Simulation Research On Active Control System For Commercial Vehicle Cab Suspension

The cab suspension system is an important part of commercial vehicle andplays an important role in improving ride comfort.Compared with half-floatingsuspension system,full-floating suspension system widely applied in commercialvehicle further improve the ride comfort.Both at home and abroad, research on thefull-floating suspension system mainly concentrate in matching structureparameters of the cab suspension system in order to decrease vibration of the cap.The study methods mentioned above can effectively improve vehicleride,however,the improvement of cap ride is limited when the vehicle drivingconditions changes because the mechanical parameters of suspension componentsare uncontrollable.Active control has been studied extensively in the field ofpassenger vehicles because it can provide control according to outside situation.Interms of commercial vehicles, the active control is difficult to improve drivers’comfort through the chassis suspension system because of the restriction of thecost and energy consumption.The cab suspension as the next part of attenuation ofvibration provide opportunity for active control in cab suspension system.A simplified ten-degree-of-freedom mathematical model of a commercialvehicle including the cab was established in this paper. It considers the vibration ofchassis and cab in all direction and can preferably verify the control effectivenessof iintelligent control algorithm proposed in this paper to the vibrations of center ofcap in directions of heave,pith, and roll.Based on mathematical model, a activecontrol system aiming to lower cap vibration and improve vehicleride for thecommercial vehicle’s cab suspension was designed. Which take cab vibration in alldirection into account.In order to reduce the heave angular acceleration, pith angular accelerationand roll angular acceleration of commercial vehicle cab, the intelligent controlalgorithm in accordance with the structural features of commercial vehicle cab isdeeply studied. Based on PID, Fuzzy-PID and adaptive control, the intelligentcontrol algorithm using active control system for commercial vehicle cabsuspension are detailedly introduced. The vibration was simulated using integralwhite noise random road as input in Matlab/Simulink and the time domaindynamics response of heave angular acceleration, pith angular acceleration and roll angular acceleration are obtained. By comparing analysis, performancecharacteristics of active control system for commercial vehicle cab suspension isstudied. The results show that by employing the active control system usingadaptive control algorithm, the control effectiveness of cap acquire a betterperformance. Meantime, the ride performance and comfortability of the commercialvehicle are improved.This paper will provide basic idea about active control system for commercialvehicle cab suspension and theoretical support for the study.