As the sailwing is free-rotating, I had to build a crazy concept where there is no electrical connection between the sailwing and the hull. A cable could easily overtwist and break. Waterproof rotary connectors have a high friction and unknown life span. All the power needed for the actuator comes from the small solar panels…

Removable keel makes the boat easy to transport. The keel is large enough to compensate high ocean winds. There are aluminum profiles reinforced by fiberglass roving inside the carbon fiber shell. The outer shell and other parts were glued together with epoxy putty. The empty space inside the keel will be filled with water that…

The lead bulb for the keel was made by sand casting – a technique developed in the Bronze Age. (Everything I do here is dangerous!) The bulb model was 3D-printed in two symmetrical parts. The first part is placed on a flat surface and prepared to be buried in “green sand”. The other half of…

The hull has been filled with a closed-cell PUR foam that will stay afloat forever. As the foam is a good thermal insulator and the batteries generate heat when charging, there are several vents leading to the battery tubes to prevent overheating. The two compartments that are not filled with foam will be completely separated…

The rudder on such a small boat can get easily entangled in seaweed or fishing nets. Numerous autonomous boats were recovered with a missing rudder which suggests that the rudder is often underestimated. This very unique rudder combines two interesting features: It avoids entanglement around the rudder shaft It’s symmetrical, i.e. the force needed to…