A Simulated Annealing Based Algorithm with Collision Free Region for the Irregular Shape Packing Problem

This paper investigates the irregular shape packing problem. The proposed algorithm constructively creates layouts from an ordered list of items and a placement heuristic. A moveable item is exclusively placed on a collision free region vertex. The container has a fixed width, while its length can change so that all items are placed on it. The objective is to find a layout of the set of items that minimizes the length of the container. The proposed algorithm has two hierarchical levels: core level with a simulated annealing algorithm, and the external level controlling the container length. The simulated annealing algorithm controls the ordered list of items and the placement of the items. If a feasible layout is found, the external level decreases the container length and applies the simulated annealing again. Otherwise, the container length is increased and the simulated annealing is applied again. Computational comparisons on benchmark problems show that the proposed algorithm generated highly competitive solutions. Moreover, our algorithm updated some best known results. Copyright c ©2011 IFAC.