Leaner Cougar for Wind Turbines

23 September 2011

Seen as ideal for shallow water wind turbine construction work, four specially designed leaner versions of the Saab Seaeye Cougar XT ROV have been ordered by Pommec, the leading Netherlands-based technology provider to the diving industry.

Custom designed to be both low profile and powerful enough to handle the strong currents found in the shallow waters off the Belgium coast, the slim-line Saab Seaeye Cougar XT Compact will be used by Pommec’s customer, D.E.C.O. (Diving Engineering & Consultancy Office), out of Bruges Belgium, during the construction of 48 turbines.

D.E.C.O. needed an ROV system that could function in strong currents and poor visibility, and also work alongside uninterruptable high-cost pile-driving operations, 24 hours a day, with zero down time.

After several meetings with D.E.C.O, Pommec and Saab Seaeye, Pommec’s solution was a completely duplicated system-spread with two identical Cougar XT Compacts in each system – making it easy to switch instantly between ROVs, and between systems.

In putting together the spread, Pommec has supplied the control and maintenance containers and the stainless steel launch and recovery system.

The two 20 foot containers, internally split between control and maintenance sections, can each store their twin Cougars and tether winches.

The launch and recovery systems will allow the Cougars to be deployed and operated in the harshest of sea conditions.
Managing Director, Rudi Pommé says that his company has sold many ROVs, but this is the first time he has used Saab Seaeye vehicles.

"Together with D.E.C.O. we’ve chosen the compact version of the Cougar XT because it is a small, but very powerful work-class ROV that is easy to handle and maintain by just two men. It is also a good product with lots of benefits.”

He explains that the Cougars will be used primarily for checking that piles are correctly positioned before each platform is fitted.

"It is not possible to use divers for this work due to poor visibility, strong currents and the need for continuous working. The Cougar XT Compact is ideal. It is more powerful than any other ROV of its size – which is why we chose it.”

The Cougar XT’s unrivalled power and manoeuvrability comes from six thrusters: four vectored horizontal thrusters and two vertical thrusters. Each has velocity feedback for precise control in all directions and is interfaced to a fast-acting control system and solid-state gyro for enhanced azimuth stability.

To create a compact version and minimise the effect of current, Saab Seaeye engineers set about reducing the frame size, buoyancy and weight. A thinner 17mm tether is also used to minimise drag. Overall, the compact design has the highest thrust to weight ratio in its class.

Each D.E.C.O. / Pommec Cougar is fitted with a low light colour camera, rear-facing B&W camera and Kongsberg high definition low light CDD camera. A Tritech Super SeaKing sonar is also fitted along with a free-issue Linquest tracking system. A bare tooling skid is supplied and a Gauntlet Plus four function manipulator.

Saab Seaeye believes that the Cougar XT Compact, along with other specialist vehicles like the Panther XT Plus, is ideally suited for the specific and growing needs of the renewable energy industry.