Modeling And Optimization Of The Stacker's Dispatch In AS/RS

Automated Storage & Retrieval System (AS/RS), as a new storage way appearing in modern logistics technology area, is playing more important roles in the industrial production. The optimized dispatch of Stacker in AS/RS is the key of high work efficiency of the warehouse.At first, based on the background of modern logistics, the paper expounds the performance of the optimized dispatch of Stacker in AS/RS in modern logistics and their relationships. Then introduce a classification of AS/RS, the basic concepts and composition, which placed foundation for further study and optimization.Second, consider the dispatch of stacker in AS/RS and its characteristic of discrete and passive, the paper introduces the timed colored Petri net modeling method and builds the modeling of the dispatch of stacker in AS/RS, which has laid a theoretical basis for further research and optimization.Third, the paper analyses the dispatch of stacker in AS/RS and the goal of the optimized dispatch of stacker in AS/RS. Specific, five dwelling point strategies were discussed and compared the performance of the five dwelling point strategies by probability model.Finally, the paper analyses the characteristic of the stacker's working mode, and proposes a method to optimize the picking operation and compound operation. Aiming at picking operations, a bound with packing model was established. After analysis of the model, pointing out that the model is a NP complete problem. Aiming compound operations, dynamic route model was established. Through the development of transformation rules corresponding to compound operations, the compound operations problem was transferred into a TSP problem. Through choosing algorithm, genetic algorithm was used to carry on these two working mode. Results of simulation showed that the optimized method could abbreviate run-time greatly, comparing with traditional methods.