Safe transfers for people and goods

The new system consists of a swivel arm robot, which allows safe transfers of people and goods from vessel to vessel or from vessel to offshore wind energy plant.

For the new Voith Offshore Shuttle, Voith Turbo Marine Engineering worked in cooperation with machine builder Momac, which manufactures special purpose machinery, automated devices and robots. Among other products, Momac specializes in robot assisted transfer systems and has developed the MOTS swivel arm robot. The MOTS swivel arm claims new performance standards for the safe transfer of people and goods by actively compensating ship movements.

The system consists of a robot installed at the bow, fitted with a transport basket with a maximum capacity of 250 kg. The freely adjustable robot arm allows safe transfers of personnel onto wind farms and also onto larger vessels, even if the seas are rough. The system can compensate vertical differential movements of up to 3.2m.

Voith combines the compactly designed MOTS system in this ship concept with the new Voith Inline Thruster in the bow. In the stern of the ship are two Voith Schneider Propellers of type VSP 18R5EC/150-1. The body of the Voith Schneider Propeller, which is fitted with several axially parrallel blades, rotates around its own vertical axle. Since this creates the same thrust in all directions, the Voith Schneider Propeller is the only propulsion system that allows highly accurate manoeuvring, as well as active roll stabilization to reduce the rolling motions of the vessel, even at zero speed.

In combination with the Voith Inline Thruster, this feature enables dynamic positioning of the ship. The Voith Inline Thruster is a propeller drive, where a permanently excited electric motor acts as the housing. Thanks to its sea water lubricated bearings, the drive is completely maintenance-free.

Voith can see a growing market for this new ship concept. On average, offshore wind energy plants have to be accessed two to three times a year for maintenance work. The time slots during which service personnel can be safely transferred to these plants from feeder ships are often very short, due to the weather conditions and high seas. In the North Sea, such transfers are, for example, only possible on an average of 230 days per year, unless the operator makes use of the combination of MOTS and dynamic positioning.

With MOTS and the Voith Offshore Shuttle, the time slot can be extended by up to 35% to approximately 310 days. Apart from the six man crew, the ship can hold up to 12 service technicians.

Due to existing tank capacities, the ship is capable of operating in the offshore wind farm for up to 14 days. The maximum sailing speed is 14 knots. A large deck surface offers room for four 10ft containers and an onboard crane in the stern area is available for loading and unloading tasks.