| With the development of the society and the advance of the scientific technology, the modern manufacturing enterprises are facing a series of problems, such as unpredictable and fast market competition that is strengthening changeably and constantly. Just under this kind of background, reconfigurable manufacturing system (RMS) becomes one of the most competitive and potential manufacturing pattern. Reconfigurable assembly line (RAL) is a new reconfigurable manufacturing system, which is designed at the outset of rapid change in structure in response to multi-type, varied-toting, multi-function, quick delivery, and sudden changes in market. As an advanced manufacturing system, RAL has become the research focal point of assembly field in recent years. As the key research content of RMS, the design and management of the RAL is an important way that can lead the RMS to further research and application. The reconfigurable assembly line management system can offer a good control and management platform for the enterprises to realize modeling, balancing, scheduling and appraising of the assembly line, to strengthen the flexibility and adaptability of enterprises and to improve the competitive capacity of the enterprises. Hence the research of key technologies for RAL management is of great importance in both theory and application. This paper focuses mainly on the architecture and management technologies of RAL. The main research contents in this paper are as follows:Firstly, the overall framework for RAL is studied. After the system requirement is analyzed for the RA1, the system framework is presented based on the multi-agent technology. The main characteristics of the system structure are analyzed, and the function model of system is designed. The key technologies of system realization are discussed and thus the research direction of the dissertation is determined.Secondly, the modeling technology of RAL is studied. Considering the characteristics of complexity, reconstructing, intelligent and autonomy of the RAL, an agent oriented timed colored Petri net (ATCPN) modeling approach is proposed. Based on the classification of resources, the resource agent is encapsulated so that timed colored Petri net base resource agent is built. The ATCPN model of reconfigurable assembly cell is composed of different resources agent by transition. According to the logical relation of each reconfigurable assembly cell, the transitive relation of message for assembly system is determined and the assembly line could be quickly reconfigured using this method. The performance indexes of ATCPN model for RAL are analyzed, and by studying the transforming from AUML model to ATCPN-based model the ATCPN-based interactive protocol simplification model is presented for the RAL to solve the conflict of the model.Thirdly, the balancing for RAL is studied. The characteristics of mixed-model assembly line for mass customization are analyzed and the special requirements of balancing are studied. The mathematical model is proposed based on three factors, which are integrated including the workstation number, the workstation load and the assembly line efficiency. Then a new hybrid genetic algorithm is developed for finding optimal solution of the problems. In order to prevent the premature convergence problem and enhance the globe-optimization capability, GA (genetic algorithms) is combined with SA (simulated annealing algorithms), and the adaptive crossover and mutation probabilities method are proposed.Fourthly, the scheduling of RAL is studied. A multi-objective optimization mathematical model is proposed, which includes three practically important objectives. Such as minimizing total idle and over workload, keeping constant consuming rate of component and minimizing reconfigurable setup cost are considered. A scheduling method for reconfigurable assembly line is presented based on Pareto multi-objective genetic algorithm, and then chromosome encoding and decoding representation of solution as well as calculations of fitness functions are described. In order to ensure the group's variety, prevent the premature convergence problem and enhance the globe-optimization capability, some key technologies such as population ranking technique, Niche technique, Pareto solution set filter and elitist selection are applied. The adaptive crossover and mutation probabilities methods are developed.Fifthly, multi-objective scheduling decision-making for RAL is studied. A new nonlinear-objective planning model of combination determining weight is presented based on improved AHP method and information entropy. In view of the grey information in the optimal selection of reconfigurable assembly line multi-objective scheduling, a decision-making model based on fuzzy grey relational analysis is proposed, and evaluation criterion of decision-making is constructed by the close degree of grey relation between decision vector and ideal reference vector which can make the results reliable and credible.Sixthly, the evaluating system for RAL is studied. On the basis of the analysing of the criterion of the evaluation index, a comprehensive evaluation model for RAL is proposed based on the hierarchy analysis according to the characteristics of the RAL and the engineering application, and the meaning of every index is analyzed. The new combination weighting method is used to calculate the weights of every index, and the index is assessed by AHP and fuzzy synthetically evaluation. The subordinative degree of evaluation object relative to optimum reference value adopting least squares principle is regarded as the evaluation criteria.Seventh, the integrated framework of the RAL management system based on CORBA is presented, and the information model for assembly resources is researched. To build and analyze the RAL modeling, the visual modeling and simulation tool for ATCPN is developed.Finally, on the basis of above research, the management system prototype of RAL is developed. The system is applied in the engineering, and the result shows the effectiveness of the system.
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