Study For The Multilink Suspension System Of An Off-road Vehicle

As the development of science,the better controllability and stability performance of the vehicle were required,not only cars,but also off-road vehicles. The suspension system which transfers all kinds of forces and torques from tires to vehicle body is the most important and direct factor that influents the vehicle controllability and satability performance.The suspension system research includes two areas.One is called suspension system dynamics and the other is called suspension system kinematics and compliance.This paper is specially to study the kinematics and compliance characteristics of an off-road vehicle independent suspension system.This paper is based on multi-body dynamic theory and the software ADAMS/CAR.According to the construction and parameters of a light off-road vehicle,this paper builds the front and rear double wishbone independent suspension systems simulation model with the ADAMS/CAR.On the basis of the rear suspension,the paper rebuilds the double wishbone orientation machine to get a multi-link independent rear suspension simulation model.Then the paper individually simulates some different experiments for the multi-link and double wishbone independent suspension assembly systems to evaluate the suspension kinematics and compliance characteristics.From the experiments,it shows that the multi-link suspension can be effectively restain the change of some parameters, such as the camber angle,the toe angle and so on.Because of the complex condition of roads that the vehicle traveles on,in order to ulteriorly study the use of the multi-link suspension on the off-road vehicle,this paper builds the body system,the brake system,the steering system and the tires by modifying the parameters in the ADAMS/CAR templates,and then builds the full vehicle simulation model with these sub-systems.Special simulations are individually made to the off-road vehicles with double wishbone rear suspension and multi-link rear suspension,including driving the vehicle through vertical step,pothole and grade.The result shows that the vehicle with multi-link rear suspension can be effectively restain the change of lateral acceleration and lateral displacement,longitudinal acceleration and longitudinal displacement,but the vertical acceleration and vertical displacement is worse than the vehicle with double wishbone suspension.At the end of this paper,some valid methods are brought forward to solve the disadvantage showed by the multi-link suspension.