Abstract Performance analysis of flexible manufacturing cells (FMCs) can help companies find the pros and cons of production processes. However, the emphasis has been on issues like cell formation, layout design and scheduling optimization. Little seems to have been done to assess the reliability of an FMC. In this paper, we develop the stochastic models for the performance analysis mainly on the reliability of two different FMCs configured from a set of teaching intelligent flexible manufacturing system (TIFMS). The closed form solutions of probabilities of system states are obtained. Then, utilization rate of equipment in the cell and productivities of the two FMCs as the performance indexes are calculated and optimized. Compared to simulation methods, the closed form solutions make calculations of the performance indexes faster and more accurate. When random variables in the stochastic models are assumed to follow non-exponential distributions, the effects of them on the performance indexes are discussed. The objective of this paper is to fill up the gap that the closed form solutions are difficult to obtain as the number of machine tool increases. Another objective is to optimize the performance indexes to help engineers better evaluate the performance of FMC. Numerical analysis cases are used to illustrate the proposed stochastic models.

中文翻译：

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多态柔性制造单元性能分析的随机模型

摘要 柔性制造单元 (FMC) 的性能分析可以帮助企业发现生产过程的优缺点。然而，重点一直放在单元形成、布局设计和调度优化等问题上。似乎很少有人评估 FMC 的可靠性。在本文中，我们开发了用于性能分析的随机模型，主要针对由一组教学智能柔性制造系统 (TIFMS) 配置的两种不同 FMC 的可靠性。得到系统状态概率的闭式解。然后，以单元内设备利用率和两个FMC的生产率为性能指标进行计算和优化。与模拟方法相比，封闭形式的解决方案使性能指标的计算更快、更准确。当假设随机模型中的随机变量服从非指数分布时，讨论了它们对性能指标的影响。本文的目的是填补随着机床数量增加而难以获得封闭形式解的空白。另一个目标是优化性能指标，以帮助工程师更好地评估 FMC 的性能。数值分析案例用于说明所提出的随机模型。本文的目的是填补随着机床数量增加而难以获得封闭形式解的空白。另一个目标是优化性能指标，以帮助工程师更好地评估 FMC 的性能。数值分析案例用于说明所提出的随机模型。本文的目的是填补随着机床数量增加而难以获得封闭形式解的空白。另一个目标是优化性能指标，以帮助工程师更好地评估 FMC 的性能。数值分析案例用于说明所提出的随机模型。