Minimizing the arm movements of a multi-head gantry machine

In printed circuit board (PCB) manufacturing multi-head gantry machines are becoming increasingly more popular in surface mount technology (SMT), because they combine high speed with moderate price. This kind of machine picks up several components from the feeder and places them on the PCB. The process is repeated until all component placements are done. In this article, a subproblem of the machine control is studied. Here, the placement order of the components, the nozzles in the placement arm and the component locations in the feeder are fixed. The goal is to find an optimal pick-up sequence when minimizing the total length of the arm movements. An algorithm that searches the optimal pick-up sequence is proposed and tested widely. Tests show that the method can be applied to problems of practical size.