Research Fellows Directory
Dr Marta Cabo
University of Southampton
I am currently working on two-dimensional cutting and packing problems with irregular pieces and guillotine cuts together with Prof Julia Bennell from the University of Southamtpon (U.K.). The motivation for this problem arises in the glass industry, where pieces are separate by means of a cut that goes from one end of the glass sheet to another, however its applications extend to other industries like textile, or furniture manufacture. Most papers assume that the pieces are rectangular and thus the cuts are restricted to be orthogonal to the stock sheet. We, however, concentrate on the less study problem, where pieces are irregular, and cuts are not constraint to be orthogonal to the sheet. The main objective is to obtain a cutting pattern for the pieces such that satisfies the guillotine cut constraint and uses the minimum number of stock sheets.
To solve this problem we developed a beam search heuristic in which each node represents a packed bin. To pack a bin we use a constructive heuristic. Throughout the search tree, we call the constructive heuristic many times, each execution packs a different bin. The main algorithm then decides wich bin is worth keeping, and bearing that some pieces are already placed, continue on packing more bins. This approach has provide very good results that are competitive with the best ones so far, and without the use of expensive specialist software, which makes our model more appealing to small companies that cannot afford the purchase of such software.
Interests and expertise (Subject groups)