A comparison of buffering strategies for the CMS routing/sequencing problem

In this paper, the authors discuss and evaluate the design of alternative buffering strategies for use in Cellular Manufacturing Systems. Of particular interest is the performance of flexible control policies for routing and sequencing in the presence of two very different buffering configurations. One approach makes use of de-centralized buffers associated with each manufacturing cell. This configuration facilitates the use of ‘push’ dispatching rules for material flow and a hierarchical control approach for routing and sequencing. The second configuration involves the use of central buffers at key routing decision points, which facilitate the use of ‘pull’ dispatching rules and simultaneous solution to the routing and sequencing problems. The authors evaluate realistic scenarios using simulation and overcome the inherent difficulty of modeling pull dispatching systems in the presence of flexible inter-cell routing conditions. Sensitivity analysis is performed relative to several key parameters in an effort to identify factors affecting Cellular Manufacturing System design in general.