Optimum Design And Performance Simulation Of Independent Suspension For Heavy-duty Off-road Vehicle

Suspension,as an important part of the chassis system,ensures the normal running of the vehicle through transferring the force and torque between the wheels and the body.Double wishbone independent suspension is frequently used on the front suspension of a vehicle;the kinematic characteristics are directly related to the vehicle handling and stability performance and tire service life.So,in the design procedure of the suspension,reasonable choice of hard point parameters of the suspension and obtaining the ideal kinematics characteristics are particularly important.In this paper,a heavy-duty off-road vehicle developed by an enterprise as the research object,for its existence in the front wheel wear and other serious problems to adjust the suspension point parameters as the main method of problem analysis and processing.And builds the vehicle handling stability model to verify the feasibility of the optimization results,the main contents include:1)Taking the double wishbone front suspension of a heavy-duty off-road vehicle as the research object,the suspension structure is simplified on the basis of the requirement of the kinematics characteristics.Using the geometric theory of spatial analysis for deduce the change of the wheel positioning parameters with the wheel jitter.Determine the reasons of the tire wear problem by analyzing the change of the wheel positioning parameters and the changing trend.2)Based on the virtual prototyping technology,the ADAMS / Insight module is used to analyze the sensitivity of the suspension hard point parameters,then the respond surface functions of toe-in angle and the variation of tread are established according to the sensitivity analysis results.The optimized design is made by using the normalized weighting method.3)The model of handling and stability performance is established by using the optimized suspension hard point parameters.According to the relevant nationalstandards of vehicle handling stability,the vehicle steering wheel angle step-input simulation test,snake-shape simulation test,steady state rotary simulation test which are the typical stability tests are operated.The feasibility of the optimization results are verified through the analysis to the results of simulation by the evaluation methods of the vehicle handling and stability performance.The optimization study is the combination of the production,learning and research.Practical issues are solved through the theoretical knowledge and the design experience.The research stage is closely combined with the production practice,and puts forward a clear solution to the problems existing in the project.In this paper,the sensitivity analysis method and response surface model optimization method have important guiding significance for the optimization design of the suspension.