Optimal Analysis of Performance Improvement Strategy for Mechanical System Assembly Process Based on Fault Tree Model

The assembly quality of the mechanical product has a significant effect on its performance. The assembly process of the mechanical product is analyzed and optimized in this paper, then the goal of the product performance improvement is achieved by using the minimum cost. Firstly, decomposing the structure of the mechanical system by the “Function-Motion-Action” (FMA) decomposition method and the meta-actions are obtained. Then, the reason of the mechanical system performance failure is analyzed at the meta-action level and a modular fault tree model is established. Secondly, all BEs and MCSs that leading to the mechanical system performance failure are obtained through FTA, and an optimization model that considering mechanical system assembly performance index and cost is established combining cost-failure rate function relationship. Finally, using the optimization algorithm to solve the problem, and the optimal performance improvement strategy under a given performance index is obtained. The proposed method is used to optimize and analyze the performance improvement strategy of the assembly process of the computer numerical control (CNC) machine tool turntable system to obtain the optimal performance improvement strategy. The goal of improving the assembly quality of mechanical products can be achieved at the lowest cost by the optimal strategy. The method can effectively guide the production process of the mechanical product, save the produce cost and improve the assembly quality.