Research On The Multi-objective Optimization And Simulation Of Workshop Layout Based On Hybrid Algorithm

All along, the planning and design of facility layout in manufacturing systems is considered as one of the most critical and the most difficult task in industrial systems, which is the important factor to improve production efficiency and reduce the operating costs. Since the reform and opening up, China's manufacturing industry has been developing continually and rapidly, but there are still some gaps with the advanced international level especially lacking sufficient attention on the planning and design of facility layout and mainly relying on experiences of designers to optimize the layout. Therefore, taking the facility layout optimization as the research object this paper studied the modeling, solving and simulation of the problem.The main research work is as follows:(1) Equipment layout optimization is a combinatorial problem in theory and belongs to a NP-hard problem when it is solved. This paper proposed a double sub-swarms——double strategies hybrid optimization algorithm based on the game theory. The algorithm can distribute and control sequence of sub-algorithms flexibly by paying utility matrix. It can also choose the best strategies for each sub-swarm, by which achieve the independent and parallel optimization of double sub-swarms. To test the performance of proposed hybrid mechanism, it was applied to the function optimization, and simulation results showed that: when the single optimization algorithm has different search features, the hybrid optimization algorithm has a higher ability of searching optimal methods and convergence efficiency.(2) The optimization problem of facility layout design in engineering often have many objectives and they are interrelated, mutually restricted and some of them even conflicting, so improving the performance of one target may lead to the degradation of other objectives, namely no plans will make all the targets achieve the optimal solution simultaneously. On the basis of multi-objective optimization technology, this paper focused on the weight setting method in multi-objective optimization and utilized the priority operator in multiple-criteria decision to calculate the weight of multi-objective optimization. It can make the weight closely related to attribute values of candidate programs and effectively avoid the compensation trading mechanism among different targets.(3) For the multi-objective optimization of multi-lines equipment layout, this paper focused on the equipment layout in company Y and set up a mathematical model to minimize material handling cost and maximize area utilization, and then solved it by PSO-CS hybrid optimization algorithm. Compared with the original single optimization algorithm such as PSO, CS, and GA, PSO-CS had a better optimization result both in material handling cost and area utilization, thus obtaining a preliminary program on equipment layout of machining area in Company Y by PSO-CS.(4) Because a series of simplification and assumption were proposed in the process of modeling, the layout scheme solved by the mathematical model had certain disparity with the engineering practice. Therefore, combining the optimization algorithm with computer simulation technology, this paper exploited Plant Simulation to simulate the layout scheme solved by PSO-CS and proposed improvement suggestions on the existing problems. The simulation showed that the final layout scheme had obvious effect in improving production capacity, reducing the logistics volume and balancing the load of machine.