A new solution for sealing the deck of an autonomous sailboat

Abstract: Maribot Vane is an autonomous sailboat project at KTH Royal Institute of Technology. The use of autonomous boats is being recognised all over the world as a cost-efficient alternative to traditional manned ships for oceanographic research. Vane consists of an International 2.4 mR hull propelled by a self-adjusting wing that is controlled by a flap. A self-steering mechanism is currently under development. Field testing of the boat in the summer of 2017 showed that the boat was leaking where the mast enters the deck as well as through a hatch covering the former cockpit. This report deals with developing a new sealing solution to prevent water from entering the boat. It should be a durable and waterproof solution. Minimizing friction is of great importance to reduce interference with the self-adjusting wing. The problem is divided into two sub-problems: creating a sealing where the mast enters the boat and designing a new hatch. A housing made of 3D-printed plastic will be placed around the mast. By establishing models depicting “worst-case” scenarios calculations are done to determine how long the housing can stay submerged as well as how much impact it has to endure when being hit by a wave. Experiments are then performed on prototypes of the housing to determine how accurate the theoretical models are. A housing that theoretically can stay submerged for approximately three seconds is developed. Analysis suggests that it is durable enough to withstand the impact from being hit by a wave. A hatch consisting of two parts is also developed. One placed in the front where the mast goes through and one in the back that should be easy to open, providing access to the inner parts of the boat even when in water.