| Quick response manufacturing system (QRMS) is raised regarding the dynamic market requirement and is the one that based on the quick response theory. The reliability enhancement for product development process is quite important for time saving and the ability of quick response in a product development circle. This paper conducts the reliability modeling and optimization method study for product development process based on QRMS.Firstly, the definition of reliability for QRMS and its calculation method has been raised based on the reliability study for advanced manufacturing system such as FMS. Further, through the analysis of a mission process, an idea and related approach to system reliability modeling is found. As for the limitation of exponential distribution in reliability modeling, the paper promoted the process modeling based on the Phase-Type (PH) distribution. By considering that the developing time follows arbitrary distribution, the reliability modeling for serial, parallel and overlapping relative in the product developing process has been built respectively.Secondly, consider the effect of design iteration, the paper conducts the study of reliability evaluation and optimization method. As for reliability evaluation, separate studies for the completed times of design activities follow exponential distribution and PH distribution and the parameters of design iteration changed along with the iterative times has been conducted respectively. As for reliability optimization, in the case of large-scale product development process, a method to solve reliability optimization modeling problem by combining Markov process and basic ant colony algorithm is used to overcome the NP-hard problem happened in optimization model solution process. Case study shows the hybrid ant colony algorithm can better solve reliability optimization problem in large-scale development process and offer a better way to optimize development process.Thirdly, given that QRMS needs to solve multiple missions in the same time, the paper conducts research in the fields of system reliability evaluation and benefits synthetical optimization. For multiple missions reliability evaluation problem, considering the effect from design iteration and resource conflicts under multiple missions, the paper uses Queueing Networks to describe the product developing process, and builds the reliability evaluation model both for development department owing single unit and the one who owns multiple units. For benefit synthetical optimization problem, based on multiple mission reliability evaluation study, the paper builds optimization model targeting at system benefit optimization by adopting the concept that optimized variable is defined as of maximum mission amount accepted by system. The paper also gives solution for the optimization parameters based on Semi-Queueing Networks Modeling. Case study and sensitivity analysis both demonstrate modeling and optimization method can evaluate the reliability of product development process under multiple mission and analyse the weakness of system. It can also provide the theoretically method and optimized strategy to improve complicated product development process and enhance the system benefit.Fourthly, the paper studies the reliability evaluation methods for overlapping relative in the product development process. With consideration that the completed times of design activities follow stochastic distribution and design iteration dose exist, the definition of the design iterative parameters have been set. Through mission process analysis, the paper gives the way to divide a mission into different phases, and builds the model by using approach of Markov process.Finally, the paper study the reliability evaluation simulated method for QRMS, conducts the software designing and development for QRMS reliability evaluation integrate with the analytical modeling above, and analyzes its application regarding practical requirement.
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