Optimization of Steel Plate Cutting Sequence Using the Tabu Search Method

This study concerns the cutting scheduling of steel plates by numerically controlled (NC) machines in shipyards. The combinatorial optimization of the cutting sequence to minimize the idle time of machines has been examined for processing many plates by multiple cutting machines. As an algorithm of the optimization, the tabu search method, which is a kind of metaheuristic technique and has been widely applied recently for such optimization problems, was adopted. The procedure was programmed on a personal computer, and calculations were carried out for test data as well as field data. It was confirmed that the idle time to wait for the next process decreased remarkably compared with the initial planned sequence, and the tabu search method was a simple and effective method to solve combinatorial problems.