Rolling horizon production scheduling of multi-model PCBs for several assembly lines

Abstract

The joint task of allocating several PCB assembly jobs to a set of production lines, load balancing of the line machines and job scheduling is considered. The production facility includes a number of assembly lines of different kinds, the PCB jobs are of different types and they should be allocated to suitable (i.e. feasible) lines. Scheduling of the production should respect the predefined release and due dates, and the objective is to minimise the sum of job tardy times. The scheduling is of the rolling-horizon-type where at the beginning of each planning period new jobs are inserted in the current non-preemptive production programme of unfinished jobs from the past planning periods. A mathematical formulation and a two-phase heuristic (including initial job-to-line allocation and schedule improving steps) are given for the problem. Experimental tests with jobs from practice were convincing.

Keywords:

• load balancing
• rolling horizon scheduling
• printed circuit board assembly
• parallel assembly lines
• PCB assembly

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 Modular and reconfigurable feeder units could be included into the model. The capacity calculations should then be revised. Component trays and other feeding techniques could also be discussed with slight modifications. We omit their consideration here in order to aid the understanding the main idea of the model and its solution.