A semi-automated approach to stowage planning for Ro-Ro ships

Stowage planning is one of the most difficult and important operational tasks in liner shipping. To help ship operators make stowage plans safer, this paper presents a semi-automated approach to creating stowage plans for Roll-on/Roll-off (Ro-Ro) ships. Based on the ship's design data, accurate two-dimensional (2D) models of vehicle decks for stowage planning are established firstly. After the vehicle types for different stowage areas have been specified manually, a more realistic stowage plan is generated using an improved lowest horizontal line searching algorithm, which maximizes the deck utilization with the constraints of obstacles and ramps. Then, the ship's flotation, stability and strength under the loading plan are assessed by using a practical method verified by Lloyd's Register (LR) test cases. Finally, computational tests on a 3800 Pure Car and Truck Carrier (PCTC) are performed and discussed, showing that the proposed method can make comparable stowage plans to that given by the ship's final loading manual and can be used onboard to improve navigation safety.