Study On Automated Warehouse’s Slotting Optimization And Simulation

With the development of modern industry and logistics technology, the traditional warehouse is not adequate for the demand of storage and retrieval. With the competition requirements of the social environment and the rapid development of the computer automatic identification technology, warehouse management information improves gradually and Automatic Storage & Retrieval System emerge as the times require and are widely applied. Traditional warehouse management usually places goods at the nearest available area when the goods arrive. It only comes from the past experience. Slotting assignment may become unreasonable after a period of operation of AS/RS, leading to low operation efficiency、high cost or unstable. Therefore, the slotting optimization has been produced. The slotting optimization management determines an appropriate location routing by goods attribute, which based on location routing strategy.Based on the research about the AS/RS, this thesis carries out a method to put the goods in the AS/RS into the optimal slots. By establishing a multi-objective slotting optimization model, we do simulation and analysis on it and get an effective solution. The main contents are as follows:1) This paper introduces the characteristics and classification and structure and also the work flow of AS/RS firstly. Do some analysis of research status in domestic and overseas and find the insufficient points then. Considering the influence of the internal and external environment, we combine the PDCA theory with slotting optimization theory. Establishing a slotting loop optimization conceptual model based on the theory and the details of four phases are also given carefully.2) Because of the many of the optimization goals, the expert evaluation method which based on trigonometric function is used to make sure the priority of goals. According to the result, efficiency of goods in or out of warehouse、shelf-life stability、balance the workload are the top three priority goals, a multi-objective model has been built by three functions.3) Weight coefficient method is selected to solve the problem considering the influence of internal and external environment to the goals in different period. Due to genetic algorithm’s advantages, a detail algorithm for the model is designed. Also the simple roulette and sine roulette selection operation are used in it.4) Sine roulette algorithm S2 is simulated by using MATLAB software to solve the respective three objective functions. Good results proved the effectiveness of S2.Setting different evolutional generations of S1 and S2, then do simulation on it, according to the results of function values and operation time, the corresponding broken line graphs are painted. After analyzing the two graphs, we find out that S1 and S2 are both efficient in solving slotting optimization problem and even S1 algorithm is better than S2 algorithm. At last, the left works of slotting loop optimization are also mentioned. Some further advices of this thesis are given.There are 38 figures, 16 tables, and 68 references in this thesis.