DESIGN OF A FLEXIBLE ASSEMBLY-LINE TO CONTROL THE BOTTLENECK

In this paper, a methodology for the design of a flexible assembly lin e system (e.g. a flow shop consisting of a set of tandem flexible work stations, a set of automated inspection stations, a loading station, a nd an unloading station, linked by a material handling system) is pres ented, while controlling the botteneck problem. This paper is a genera lization of earlier work1, where a design strategy far a simplified ve rsion of a similar manufacturing system was proposed. In this paper, t he loading process is stationary with identically distributed interarr ival times, and defective work-pieces are reprocessed at the correspon ding workstations. Here, the performance of the assembly line is model led by a non-Markovian queueing network with finite capacity queueing nodes. Based on this queueing network, a stochastic optimization model is then presented to select the minumum required local storage sizes of the workstations and the transporter stations such that the resulti ng probabilities of finding each workstation and each transporter stat ion blocked (e.g. full) are sufficiently close to zero. To solve the p roposed optimization model, a heuristic algorithm is then developed. F inally, an example is presented, and the relative accuracy of the prop osed algorithm is investigated by a simulation study.