Braking System Performance Optimization Design Based On Analytical Target Cascading

The development of automotive products is guided by the idea of hierarchicaldegradation, define the vehicle design target and decompose the target to the assembly andparts, then complete the vehicle design by addressing the assembly design. Traditionalmultidisciplinary design optimization methods rarely adopt the hierarchical optimization ofthis idea and it is difficult to solve the coupling between subsystems in the product design.This thesis presents a useful optimal method named Analytical Target Cascading（ATC）.Using the method, the car will be stratified, and then solve the problem of design in eachlayer, finally, complete the vehicle design. The method is applicable to the design ofcomplex mechanical products, such as aircraft, automotive and so on.This paper analyzed the idea of ATC and the optimization problem, established thebasic framework of ATC. Taking braking deceleration and characteristics of pedal sense asthe optimization goal, using ATC to guide the braking system design, mainly include thefollowing:Firstly, this paper describe the basic idea of ATC in theory, investigate the targetdefinition and target decomposition steps, Analysis the relationship between the system andthe module within the system. Including target which transmission to the lower layers, thefeedback to the up layers and the specific treatment methods about deviation and the contactvariables. Establish the basic framework of ATC.Secondly, several commonly used nonlinear optimization algorithms are described inthe paper, we can understand the advantages and disadvantages through comparing thesealgorithms, it will provide a theoretical basis for the specific optimization in ATC. Takebraking system as an example, build the braking system model, divide the system into avariety of sub-modules, complete the target decomposition and build the mathematicalmodel.At last, in order to prove the feasibility of the ATC, combine the theory with practice,taking the brake pedal sense and the actual needs of the braking deceleration as theoptimization goal, which is provided by Changan Automotive Company Limited. Use ATCmethod for the design parameters of braking system. The optimization results show thatATC method is accurate for the design.This thesis provide an automobile matching design and product developmentoptimization method for domestic manufacturers, it not only ensure the design accuracy of the vehicle layer, but also ensure all system assembly and components designed to meet theneeds of their characteristics. The product will be more in keeping with the actualrequirements.