Models for manufacturing system design: Operation assignment and product grouping

In this dissertation we consider operation assignment problems arising from a printed circuit board assembly process. The research was inspired by an application at Hewlett Packard where hundreds of types of printed circuit boards require the insertion of a number of components. The components can be inserted manually or by an automated insertion machine. The machines are limited in terms of the number of different component types that they can hold.;The first problem investigated is how to assign the boards and components to the machines and manual process so as to minimize cost. An optimal solution technique is developed for the single machine case and for the multiple machine case where boards are not allowed to be set up on more than one process. In addition, a heuristic is developed which gives near-optimal solutions (within 0.01%) with much less computational effort.;We extend the analyses to consider quality issues. When boards are set up on multiple processes, assembly is more complicated, leading to increased operator error, decreased quality, and higher rework costs. Rather than forcing boards to be produced entirely on one process, or ignoring these costs of lost quality, we explicitly include a cost when boards are produced on multiple processes. We develop an optimal solution technique, as well as a heuristic that is shown to yield near-optimal solutions.;The solutions to the minimum cost problem can have a wide disparity in workload across the machines. Thus, we next consider the problem of simultaneously minimizing cost and balancing the machine workloads. Four heuristics are developed whose primary goal is still to minimize cost, yet yield solutions with a more balanced workload. One of these heuristics is shown to outperform the other three for most problems.;Although the problem this dissertation specifically addresses is that of partially automated PC board assembly, the results apply to a more general set of problems. Other applications include completely automated PC board facilities, general operation assignment problems, flexible manufacturing systems, and group technology problems.