Reduction of printed circuit board group assembly time through the consideration of efficiency loss of placement time

In a high-mix middle-volume production environment for printed circuit board (PCB) assembly, the production efficiency strongly depends not only on the tactical level of how to group PCBs but also on the operational level of how to assign feeders and determine placement sequences in the group setup strategy. The present study discusses the problem of clustering PCBs into groups in such a way that total placement and setup time can be minimized. This problem is motivated by a situation that the reduction of group setup-time and efficiency loss of placement time should be balanced in a PCB group setup optimization. This research incorporates placement time into the PCB job grouping and presents a weighting similarity measure. To solve component-feeder assignment and placement sequences for a family of PCBs, an efficient procedure based upon an ant colony optimization (ACO) algorithm is developed. Group setup performance is evaluated and compared under a variety of grouping algorithms. Experiments are conducted to discover situations where the consideration of efficiency loss of placement time can make a significant improvement in PCB group assembly.