Performance Optimization of an Imbalanced Flexible Manufacturing System Using Taguchi Approach

Considering the diverse range of manufacturing capabilities of modern manufacturing systems, uniform distribution of load onthe workstations (WSs) is difficult to achieve as some of the WSs are required to process more parts than others or sometimes processing time of a WS can differ from one part to the other. These situations lead to unbalancing of the manufacturing system. The objective of this paper is to study and optimize the performance of an imbalanced Flexible Manufacturing System (FMS) under different operating environments. The FMS under consideration manufactures three types of parts having different processing characteristics. The experimental variables for the study are buffer capacities at the WSs, reduction in processing time of bottleneck WS, WSs processing time distribution, and parts release control. Throughput, average work-in-process (AWIP) and Average Throughput Time (ATT) are taken as performance measures. Taguchi approach is used to analyze the effects of above variables and establish the combinations of best factor levels to get the optimal performance. All variables are found to affect the performance to some extent. Reduction in processing time of the bottleneck WS and processing time distribution affected the performance of the system severely. The best factor level ombinations differ for parts having different processing characteristics. This paper may help industry in analyzing the performance of an imbalanced FMS.