The Technologies And Instantiation Research For Knowledge-based Variant-design Of Product

Recently the market competition has been changing to reduce time-to-market and satisfy the personality demands of buyers. In order to reduce the developing costs, increase the product developing speed; enterprises must reuse the available resources farthest. But satisfying the personality demands means that we can't reuse the available resources completely. The effective method that solves the conflict is to adopt the strategy of variant design. Taking the vehicle as example, this paper studies the variant-design technology. Vehicle variant-design divides into two levels: variant design based platform, and variant design based platform variant. Variant design based platform variant is the effective method that satisfying the more personality demands of buyers. Variant design of product is a knowledge-based process; knowledge is the key aspect that implements the strategy of variant design. So this paper proposes the technology for knowledge-based variant design, and deeply researches its technology and implementation combined with the variant design of automobile rear-axle that is the important aspect of vehicle platform variant. Main contents of this paper are summarized as following:(1) On the basis of deeply researching the processes and characteristics of product variant design, this paper puts forward the product model and the intelligent reasoning model for variant design; they are the hierarchical model for product variant design and hybrid reasoning model that CBR is the core. The frame of knowledge-based variant design is puts forward. The system includes four sub-systems: the product recourse base subsystem, the product recourse managing subsystem, the variant design subsystem, and the design evaluation subsystem.(2) Taking the vehicle platform variant as precondition, this paper deeply researches the function-structure and function-structure decomposition of rear-axle. The rear-axle product model for variant design is built using general CAD software (Unigraphics). (3) This paper deeply researches the evaluation index system, the evaluation methods, the building of FE model, and the processing method of load etc. The evaluation index system of automobile rear-axle is built, and some evaluation models are set up.This paper deeply researches the building of rear-axle FE model, and the FE(4) technology of hybrid system, and the processing of damp and road excited motions etc. FE model of rear-axle system is built. A rear-axle variant design is evaluated using the FE model. The solution for the rear-axle shell crack is represented.(5) The KBE system of rear-axle variant design is developed using the general CAD software (Unigraphics) and general CAE software (MSC.Patran, MSC.Nastran).