Study On The Front Wheel Shimmy And Riding Stability Of Heavy Truck

The lateral shock absorber and lateral stabilizer bar system which are important component parts of heavy trucks effectively suppress front wheel shimmy and vehicle roll motion and significantly improve driving safety and riding comfort.However,the analysis and calculation process of front wheel shimmy and roll motion is complex,and restricted by slice deformation and problems of nonlinear oil losses,lateral stabilizer bar system stiffness and rubber bushing radial deformation,the theory study damping matching method of lateral shock absorber and design method of lateral stabilizer bar system have not been proposed at present.Mostly,the parameters of lateral shock absorber and lateral stabilizer bar system are often designed by using computer simulation,so it is difficult to get reliable valves parameters value.This can't satisfy the driving safety and ride comfort of heavy trucks.In this paper,some research was conducted aiming at the problems,the innovations are as follows:(1)To heavy truck as the research object,analyzing driving stability and steering flexibility of heavy truck,based on the three degree of freedom vibration model of front wheel shimmy system and the lateral concentration model of tire,the minimum critical damping coefficient of lateral shock absorber was got by Hurwitz criterion.(2)The biggest critical damping coefficient was got by the relationship of tires spin situ resistance,the lateral damping force and the hydraulic power steering force,and the optimal damping coefficient of lateral shock absorber are obtained by golden section method.(3)Based on the vehicle roll models design the matching stiffness of suspension lateral stabilizer bar system,and the radial deformation of rubber bush was computed by elastic mechanics and superposition method of deformation.Based on the Castigliano Second Theorem,the endpoint displacement of stabilizer was dissolved,and mathematic models of theoretical parameters of lateral stabilizer bar system were built.Though modeling simulated and tested by Matlab/Simulink,the results showed that the optimal damping coefficient and design methods of valves parameters of lateral shock absorber are accurate and reliable.Meanwhile,it can decay front wheel shimmy Angle and roll Angle of truck body,and effectively improve riding comfort and safety.Using ANSYS certificated the parameters design method of stabilizer bar system,the results showed that the diameter of stabilizer bar,the axial length and inner sleeve thickness of rubber bushing is accurate and reliable.This study on the design and development lateral shock absorber and stabilizer bar system of heavy truck,has an important theoretical significance and practical application value.