The Optimization Design Research Of Ackerman Steering Linkage Based On Approximate Model Technique

When the car on the road, Ackerman steering linkage has a great influence onhandling and stability of vehicle and tire wearing. When the automobile suspension isindependent suspension, if the design of Ackerman steering linkage is unreasonable,the suspension guiding mechanism of the automobile suspension system and thesteering bar system of steering system produces mutual movement interference, frontwheel shimmy, car running deviation etc will appear when the car on the road,destroying the vehicle handling and stability, tire wearing becoming more intense. Sothe optimization design of Ackerman steering linkage becomes particularly important.In this paper, a cross-country vehicle is selected as the research object, relatedresearch and exploration of Ackerman steering linkage optimization design is madeusing the approximate model technology.First a virtual front vehicle system of the cross-country vehicle was built byADAMS. The system includes double wishbone suspension and rack-pinion steer.Steer and toe angle simulations were running in this model, getting the toe Anglecurve along with the change of wheel hop and ackerman error curve along with thechange of wheel angle. Then using ADAMS Insight module analyses the effect ofAckerman steering linkage key point to toe Angle changes when the wheel beats andsteering ackerman error.According to the sensitivity analysis, random sampling of Ackerman steeringlinkage key point is done by using the optimal Latin hypercube experimental design,giving the sampling value to the virtual prototype model of the front suspension andsteering to get toe angle and ackerman error response value. The approximation modelis established by Matlab program,which includes key points with the toe angle andsteering wheel steering trapezoid ackermann error, setting the optimization goal,multi-objective optimization design is done. Finally through the establishment of thevirtual prototype model of the vehicle, according to national standard, the vehiclesteering stability experiment, using the established virtual prototype model of thevehicle, the experimental performance of vehicle before and after optimization wereanalyzed in steady state, steering back steering stability and crawling, gettingevaluation score of the simulation experiment results. Contrast control stabilityevaluation score values before and after optimization shows that this paper withadopting optimization analysis method is very effective, with the high feasibility. In this paper, the multi-objective optimization design of ackerman steering linkageis done, selecting key points of ackerman steering linkage as design variables,regarding toe angle changes when racing at the wheel and steering ackermann error asthe objective function, the approximation model of ackerman steering linkage is setup, using multi-objective particle swarm optimization algorithm to get toe anglechange and ackerman error pareto solution set. Through exploration and research, thispaper got a kind of effective method for the optimization design of ackerman steeringlinkage, this is a good practical guiding significance for innovation and developmentof automobile ackerman steering linkage.