Tackling the Irregular Strip Packing problem by hybridizing genetic algorithm and bottom-left heuristic

This paper addresses the Irregular Strip Packing problem, a particular case of Cutting and Packing problems in which a set of polygons has to be packed within a rectangular object. To identify good quality solutions, we propose a hybrid methodology based on a meta-heuristic engine (i.e., Genetic Algorithm) and a well known placement heuristic called Bottom-Left. In addition, differently from several approaches presented in the literature, we investigate the application of the No-fit Polygon as a placement tool for obtaining local optima. The results are further improved by a shrinking algorithm that works within the meta-heuristic component. To assess the potentials of the proposed methodology, computational experiments performed on a set of difficult benchmark instances of the Irregular Strip Packing problem are discussed here for evaluation purposes.