The goal of the cutting stock operation is to minimize trim losses, and thus maximize the utilization of material by laying out the maximum possible number of parts on a sheet. In order to maximize the utilization of raw material, different parts, or a number of parts of the same type, are cut from the same sheet. Historically, the laying of parts on a sheet has been performed by humans. Since this job is very time-consuming, there is an increasing interest in automating this process. Automationrequires the development of solutions that can be extended to a variety of parts. The success of mathematical programming techniques in generating optimal solutions, however, has been limited to rectangular parts. Therefore, in recent years a number ofheuristic algorithms have been developed for laying out irregular (asymmetrical), regular (symmetrical) and mixed parts. However, the utilization obtained by such techniques is no higher, and in many cases is lower, than part layouts generated by humanoperators. This study focuses on extracting the human intuitive thought process involved in laying out parts on a sheet. The first experiment, conducted with four near-rectangular convex parts, investigated the feasibility of extracting the humanintuitive thought process involved in laying out parts. The results indicated that it was possible to extract such strategies and formalize them. This prompted a second experiment to determine whether the previously extracted strategies could begeneralized. In addition to convex parts, concave parts and their mix were also considered. The results indicated that it is possible to extract and generalize strategies that lead to higher utilization. The third experiment compared the utilizationobtained from a mathematical algorithm with the utilization obtained in one of the combinations of the second experiment. The fourth experiment compared the utilization obtained from heuristic trained group and un-trained group. It was observed thatheuristic trained group achieved higher utilization than un4ralned group. The proposed heuristic can be used to train new operators for laying out parts on a sheet as well as automating the parts laying out process to maximize sheet utilization.
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