Workshop Crane Scheduling Simulation Method Based On Multi-agent Steelworks Study

Crane transportation is the most important logistics transportation mode in steel production process which has the function of handing and transportation. Crane scheduling has become the key of every production procedure whether can match and operate coordinately, and has become the decisive factor of production process operates stability and high efficiency in workshop of steel-making plant.The crane scheduling problems of metallurgical field were studied relatively at home and abroad, are mainly focused how to solve the spatial conflict among cranes. Research methods were used which include based on mathematical programming method, based on heuristic method, based on simulation method and based on hybrid intelligent scheduling algorithm, but these research methods can not simultaneous eliminate the spatial conflict and time conflict among cranes, and can not timely and effectively satisfy the demand for crane of tasks due to problems considered are not comprehensive. So it is necessary to study a method which can simultaneously and effectively eliminate the spatial conflict and time conflict among cranes. This dissertation aims at cracking the hard nut to make crane scheduling in workshop of steel-making plant. It is our task to explore an adaptable and flexible new method that not only effectively eliminate the spatial conflict among cranes, but also effectively eliminate the time conflict among cranes.Multi-agent System can decompose complex and big system into many simple agent which have simple structure, can interact with each other, and can be easily managed. Multi-agent Technology is especial suitable for solving complex problems with the large interaction. According to the characteristics of crane scheduling in workshop of steel-making plant, this dissertation introduces the thought of Multi-agent, builds model of crane scheduling in workshop of steel-making plant based on MAS. The scheduling system mainly includes crane agent groups, work station agent groups and coordination management agent, and introduces global target into the model in order to make strategies of crane scheduling and operation results match with global target and production practice in workshop of steel-making plant. The operation principles of this simulation model can be described as follow. Firstly, the global target is introduced into the system. Secondly, the global target is changed to local targets by the time backward inferring algorithm in the coordination management agent. Then, the target work station is selected by the local targets and rules. Finally, crane agent groups choose suitable crane to finish the transportation tasks. This system has dynamic property, the property of optimizing local target and the property of guide global target, it can realize crane dynamic scheduling in workshop of steel-making plant, can effectively portray and reflect the basic characteristics of crane scheduling in workshop of steel-making plant, and has extensive applicability in optimizing crane scheduling.According to actual production conditions of No.3 steel-making plant in Kunming Iron and Steel Co., LTD, simulation model of logistics system was established and the simulation results was compared with actual data, so the results show:(1)The simulation model of logistics system in steel production process based on Multi-Agent is correct and effective. A MAS-based model for simulating crane scheduling is used to study the crane scheduling problem in melt shop according to the characteristics of crane dynamic scheduling and on the basis of considering fully the various constraints, such as time, space and resources. A new way which can solve crane scheduling in melt shop is explored.(2)The global target and information is introduced into the model of crane scheduling based on MAS, and the global optimization is done.The results for simulation experimentation show that the maximum of simulation transport time is 11 minutes lower than the actual transport time at the same condition and the average transport time is 7.5 minutes lower. At the same time, the utilization ratio of continuous casting machine go beyond 85%, and even is up to 95.5%.The utilization ratio of each crane is balanced, and it is not beyond the specific limit (70%) for keeping production normal.All of this can make the strategy of crane scheduling be consistent with the global target in considering the condition of whole workshop.The research works show that the simulation method of crane scheduling in workshop of steel-making plant based on MAS is feasible, and it can depict the basic characteristics of cranes in workshop of steel-making plant efficiently. The method has the extensive applicability to optimize the system of crane scheduling.