Using the wind as a driving power for the shiplet requires of course some sort of sail – a field of design with a lot of interesting developments and alternatives these days, be it Flettner rotors, (inflated) wing sails, DynaRigs, kites and other concepts. In an early stage of the project the Flettner rotor was our preferred propulsion system, also because it seems so weird that due to the Magnus effect a bunch of rotating cylinders could do the job. But the closer we looked at it, other alternatives seemed more feasible, lightweight and energy-efficient. Inflated wing sail look really very promising as a future solution. But for the prototype scale model it does not feel realizable with reasonable effort at the moment. So finally we decided to try a DynaRig like rigid profile mounted to pivoted masts, where the driving of the rotation will be implemented by radio controlled servos. The mast supports are organized in pairs with one servo each.
Since we want to keep the shiplet balanced and prevent it from tilting while sailing, we need to counteract the side-fed wind forces with its stabilizing fins and ballast tanks. For a better and ideally preventative compensating reaction to gusts and changing wind conditions we want to measure the sideward forces at the front mast support with a low-cost weighing cell sensor.
Each pair of mast supports is mounted with carbon fibre bolts that are fixed in the deck framework.