Application And Optimization Research Of Semi-trailer's Mixed-model Assembly Lines

With the adjustment of China industry policies, the automobile industry is developing rapidly in recent years. The number of production and sales of semi-trailer is increasing rapidly. The retain number of semi-trailer will steady increase in the next few years. With the development of the market, the needs of users are diversity about model variety, as well as the characteristics of the semi-trailer is multi- varieties and low-volume, so the production method of mixed-model assembly can use in the production of semi-trailer. The production of mixed-model assembly is one of just-in-time production methods. It refers to an assembly line produce a variety of models at the same time. This production method has relatively high requirement to the entire production system. It requires that the parts and modules assembly join into the production line on time according to the beat.Optimization scheduling is an effective way to improve the productivity of mixed-model assembly lines. This article overviews the four objective functions of optimization scheduling on mixed-model assembly lines, and establishes mathematical model in the goal that production line should ensure uniform about the use rate of various components. The mixed model assembly line scheduling problem is a complicated combinatorial optimization problem. After analyzing and comparing a variety of optimization algorithm of solving combinatorial optimization problems, it selects ant algorithm as the optimization algorithm for solving the mixed model assembly line scheduling problem.Ant algorithm is an optimization algorithm of simulating natural ant-foraging rules. It has the advantages of global convergence and high-quality in solving combinatorial optimization problems. It suit to solve large-scale combinatorial optimization problems. This article overviews the ant algorithm at first, including principle, characteristics, implement methods as so on, then analyses the relevant parameters in the impact of ant algorithm, finally describes in detail the steps of solving the ant algorithm through an example. On the basis of outlining the production of the Semi-trailer, it uses successfully ant algorithm to solve semi-trailer's mixed model assembly line scheduling problem at first, then establishes the optimization scheduling system of semi-trailer's mixed-model assembly lines, finally demonstrates operation steps through an example. Comparing the objective function value by ant algorithm with the objective function value by some other optimization algorithm, the conclusion shows that it is appropriate to use ant algorithm in the mixed model assembly line scheduling problem.