Design Optimization And Performance Analysis Of Multilink Suspension For Formula SAE Racing Car

The suspension of the FSAE racing car will directly affect vehicle handling and stability performance.The double wishbone independent suspension used in the formula car of China has some problems,such as the lack of lateral stiffness,the difficulty of parameter adjustment and the high requirement of the rim offset.The advantages of flexible design,suspension stiffness is large enough,strong stability,easy to adjust parameters let's the using of the multi link suspension in the FSAE becomes a focus.In order to overcome the shortage of the car in the course of the competition turned back positive force is too large,oversteer tendency and anti drive backing caused the spherical hinge gap,in this paper,we design and optimize the front multi link suspension and steering system,and analyze the performance of the system.In addition,the mechanism of the influence of the hard points on the performance parameters of the multi link suspension is investigated.In this paper,firstly,The ‘two instantaneous axis method' is used to design the geometric assembly model of the multi link suspension guide mechanism.Secondly,according to the rules of the game and track setting-out drawing to choose what kind of steering gear is suitable for the multi link suspension of the FSAE car.By comparing three kinds of steering geometry,which are ideal Ackerman,reverse Ackerman and parallel steering,we can design the geometry of the Ackerman and the steering trapezium of the target vehicle.At the same time,the relationship between suspension and steering system is analyzed by using roll test based on the geometry assembly model.Thirdly,building the multi link suspension and steering virtual prototype in the ADAMS/Car to design the parallel travel and static loads simulation experiment.In this experiment,the performance of multi link suspension and its matching with steering system are investigated.Based on the ADAMS/Insight module,this paper analyzes the influence factors of the relative parameters of the hard point coordinates on the pre simulation and designs the multi-objective parameter optimization.Moreover,compared the suspension and steering performance parameters before and after optimization and analyzed the test data.The results show that the performance of multi link suspension after optimization has improved significantly and proves the feasibility and preliminary design method optimization method.Furthermore,the sixth chapter compares the current damping system driving form,layout and design of anti roll bar suspension structure determining the target car suspension system structure and performance parameters.Then combined with the parameters of the vehicle suspension and static parameters to calculate the frequency of the front suspension and check the strength of the front suspension rod.At the same time,ADAMS/Car and ANSYS/Workbench software based on the former multi link suspension control arm,rocker arm and shock absorber bearing strength analysis is conducted to ensure the reliability of structure in the actual game process of the car.Finally,the paper summarizes the key points and problems in the design and optimization of FSAE multi link suspension.At the same time,some suggestions are put forward for the research of the multi link.