Research On The Target Cascading Of Vehicle Handling And Stability Based On Performance Classification

The forward development of automobile is the key to ensure the vitality and competitiveness of enterprises,and is the best way for enterprises to gain a foothold in the increasingly competitive market.In the forward development of the vehicle,it is unavoidable that the performance indexes must be decomposed to the assembly parts.Most of the domestic auto companies' ability of target cascading is poor.In this paper,the decomposition methods at home and abroad are investigated.And found that the large-scale optimization method can only decompose one or two performance indexes.When the performance index of decomposition is more,it is easy to be difficult converge and coupling and many other problems.In order to solve the problem of large scale optimization method,this paper presents a method of target cascading based on performance classification.The main work of this paper is divided into the following four aspects.The target cascading method is researched.In this paper,the theory of cascading,the decomposition method,the performance index and the optimization strategy are studied.Analytical target cascading is emphatically studied.According to the different decomposition methods,the dynamic model and the optimization algorithm are different.But the thought of decomposition is very similar.There is no uniform approach for target cascading.This paper investigated and researched the performance target cascading methods at home and abroad and found that the method of combining ‘Isight' with the complex vehicle dynamics models is the most popular.However,the large-scale optimization method can only decompose one or two performance indexes.When the performance index of decomposition is more,it is easy to be difficult converge and coupling and many other problems.In order to solve the problem,this paper presents a method of target cascading based on performance classification.In addition,this paper studies the NSGA-optimization algorithm used in the decomposition processIn this paper,7 representative performance indexes are selected,and the performance indexes are divided into three categories: vertical performance,roll performance and lateral performance.Every kind of performance index use simple vehicle dynamic model to decompose.In this method,relevant parameter of performance index are divided into two types: vehicle design parameters and assembly parameters.The values of the relevant parameters was determined by the decomposition process.This method achieve a rapid decomposition of handling stability index to the vehicle assembly characteristics.This paper also uses the this method to do a decomposition example to demonstrate the feasibility and applicability of the decomposition method.