SkySails' first cargo ship, with a huge computer-controlled kite, was recently flagged off by Eva Luise Koehler, wife of German President Horst Koehler.

The ship MV Beluga SkySails started its maiden voyage from the city of Bremerhaven, Germany to South & North America (and back) and the SkySails-System with its 1,722 square-foot towing kite has been put into operation successfully.

This new technology can tow cargo vessels and superyachts, reducing fuel consumption by 10 to 35 per cent on annual average. SkySails used Maple symbolic mathematical software for engineers to develop its simulation devices.

SkySails GmbH & Co. KG, based in Hamburg, Germany, develops, produces, and distributes towing kite wind propulsion systems for modern means of sea travel and transportation. These systems make the operation of ships more profitable, safe, environment friendly, and independent of scarce oil resources. The SkySails system consists of a large towing kite similar to a paraglider, which is navigated by a fully- automated control pod and is connected to the ship via a towing rope. The control pod performs similar tasks as a paraglider pilot - shortens or lengthens the control cords, thus changing the aerodynamic profile of the towing kite - and governs its flight path.

The traction forces are transmitted to the ship via a traction cord made of high performance synthetic fibres, ensuring high load capacity as well as low weight and low elongation under load. The control system is comparable to an aircraft auto pilot. An automated routeing system, aligned with historic routes of large cargo sailers, will allow cargo ships to reach their destination as quickly, and at a much cheaper cost.

SkySails used Maple to develop its simulation software. Maple was chosen for its symbolic computation engine, which considerably simplifies the derivation of the equations of motion for multi body systems. Many matrix operations and derivatives needed to be applied in order to set up the equations in three dimensions. Editing the three-dimensional mathematical models by hand was not feasible within the project's time frame.

Skysails project team said: “Using Maple was very easy and quick. The computations we used are probably very basic for Maple, but they were extremely effective for SkySails. When testing the simulator, the correctness of the mathematical model is crucial. With Maple, there was nothing to worry about!”

A flight simulator presenting the movements of the kite system in real time is under development.

Skysails Maple