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Platform one Researchers at the Fraunhofer Center for Maritime Logistics and Services have designed an unmanned tugboat for making berthing and unberthing operations safer and more efficient (writes Rory Jackson). “Full autonomy makes sense for open- sea missions, but tug operators require degrees of skill, awareness and reaction in tight spots that are hard to model algorithmically,” said Hans-Christoph Burmeister, group manager for sea traffic and nautical solutions at the centre. “It’s also a very risky work environment. When something goes wrong, it can easily mean damage to the bow tug or harm to the operator,” he said. “On the other hand, tug crews can spend many hours a day waiting idly for a favourable tide. A remote operation solution could, for example, enable this limited but skilled workforce to perform work in Bremen, say, while waiting for a tide in Hamburg.” The FernSAMS or RoboTug concept is a ‘carousel tug’, with an unmanned deck that features a rotating platform with a winch and an extending, servo-actuated arm for automated line handling. Development so far has involved defining the operating scenarios, designing the tugboat, programming automation code for the complex line- handling tasks – while balancing the task of maintaining stability aboard the tug – and designing simulation models for testing, training and validation. Validation of the controls and sensors, as well as autonomous capabilities in situational awareness, line handling and propulsion control, will take place at the MTC (Marine Training Center) Hamburg, where Fraunhofer CML conducts ship- handling simulations. FernSAMS uses a Voith Schneider Propeller (VSP) system for propulsion, which has been designed for dynamic positioning, making it suitable for the latency requirements of unmanned operations. The centre partnered with Voith to help design the vehicle. The VSP uses a ‘propeller well’ under the vessel, which enables 360 º variation of thrust direction. Comms systems are provided by MediaMobil, and additional hydrodynamics research will be carried out by the Hamburg University of Technology and the Federal Waterways Engineering and Research Institute. Tugboat plan underway Marine vehicles