Analysis And Optimization Of Dual-front Axle Steering Characteristics Of Heavy Vehicle

The heavy-duty commercial vehicles in the domestic market are increasinglycommon, but there are some problems and negative phenomena during their designand use. Among them, tires’ serious wearing phenomenon and running deviation ofmulti-axis steering automobile is very common, therefore, it is necessary to make thispoint to be an important research topic. This article will understand and research thesteering system dynamics deeply focus on a four-axis heavy vehicles using dual-frontaxle steering system.In this paper, the mathematical models of this vehicle’s steering and suspensionsystem was established, and the accuracy of the model was verified base on ADAMS’virtual model and real vehicle steering test. Summed up the kinematics regularity ofdouble front axle steering system, and the motion interference between suspensionand steering system was researched. Knowing the steering wheels’ ideal anglerelationship in steering basic principles, took an optimization design of not only theincompatibility of the movement between suspension and steering linkage, but alsothe trend of tires’ non-pure rolling base on the mathematical model.In order to analyze the vehicle steering dynamics of multiaxial heavy vehicleswith dual-front axle steering system, a3-DOF angle input handling dynamics modeland a4-DOF force input handling dynamics model based on the real vehicle wereestablished. Analyzed the situation about axle-load distribution of multi-axle vehicle,and the influence to handling stability taken by the wheel vertical load’s re-allocationcaused by the roll movement was researched，and the multi-DOF state differentialequations was established. Based on Simulink，the steering dynamics simulationmodel was built and the simulation analysis was carried out, then combined with thereal vehicle handling and stability tests, the accuracy of the simulation model wasverified.The research results of the above work show that the kinematic analysis methodsof the dual-front axle steering system and the mathematical models of the steeringmechanism in this article are correct. The optimization method of the steeringcharacteristics combined with the interference between suspension and steering rod iseffective，which has reduced the tires’ wear and improved the moving compatibilitybetween suspension and steering system, making the road performance of this vehiclemuch better than before. The methods of establishing the3-DOF angle input steering dynamics model and the4-DOF model force input steering dynamics of the multiaxialheavy vehicles with dual-front axle steering system are correct, and they are with agood reference value to the analysis of handling stability of multi-axis heavy vehicleswith biaxial steering system.