Solving Nesting Problems with Non-Convex Polygons by Constraint Logic Programming
نویسندگان
چکیده
In this paper an application of constraint logic programming (CLP) to the resolution of nesting problems is presented. Nesting problems are a special case of the cutting and packing problems, in which the pieces generally have non-convex shapes. Due to their combinatorial optimization nature, nesting problems have traditionally been tackled by heuristics and in the recent past by meta-heuristics. When trying to formulate nesting problems as linear programming models, to achieve global optimal solutions, the difficulty of dealing with the disjunction of constraints arises. On the contrary, CLP deals easily with this type of relationships among constraints. A CLP implementation for the nesting problem is described for convex and non-convex shapes. The concept of no-fit polygon is used to deal with the geometric constraints inherent to all cutting and packing problems. Computational results are presented.
منابع مشابه
Applying Constraint Logic Programming to the Resolution of Nesting Problems
Nesting problems are combinatorial optimisation problems where one or more pieces of material or space must be divided into smaller irregular pieces, minimising the waste. In OR, the state-of-the-art in nesting problems is to solve them by means of heuristic algorithms; the use of mixed integer programming models can handle only rather small instances. The satisfaction of geometric constraints ...
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