Generating Optimal Stowage Plans for Container Vessel Bays

Millions of containers are stowed every week with goods
worth billions of dollars, but container vessel stowage is an all but ne-
glected combinatorial optimization problem. In this paper, we introduce
a model for stowing containers in a vessel bay which is the result of prob-
ably the longest collaboration to date with a liner shipping company on
automated stowage planning. We then show how to solve this model ef-
ficiently in - to our knowledge - the first application of CP to stowage
planning using state-of-the-art techniques such as extensive use of global
constraints, viewpoints, static and dynamic symmetry breaking, decom-
posed branching strategies, and early failure detection. Our CP approach
outperforms an integer programming and column generation approach
in a preliminary study. Since a complete model of this problem includes
even more logical constraints, we believe that stowage planning is a new
application area for CP with a high impact potential.