Inspection of the mooring lines and the export cable of a Floating Wind Turbine

Hello all,

We have done some video surveys of the mooring lines and the export cable of the largest grid-connected Floating Wind Turbine in France. The Floatgen turbine, 2MW capacity, is being tested at the SEMREV offshore test site operated by Ecole Centrale de Nantes.

Although this was a very steep learning curve for us, we got some very nice results.

Although the wind (<5 knots) and waves (<1m) conditions were ideal, the lines and cables were still moving. It worked OK, however a video stream with less latency and a professional controller would definitely improve survey performance. Several solutions are already described in the forum, we just need to purchase/implement them before the next job !

Many thanks to BlueRobotics people for the product and support. Many thanks to the people on this forum.

Figure 1: Ready for diving (Credits: Ecole Centrale De Nantes)

Figure 2 : ROV approaching the hull and fairlead of a mooring line, look for some yellow ROV not blue! (Credits: Ecole Centrale De Nantes)

Figure 3: Underwater example but for the mooring line of a nearby special mark buoy.


Nice, are you using the Waterlink GPS or third party equipment for Navigation?

Hi Fazdli

We did not use any positioning on the ROV itself. The screenshot of OpenCPN only shows the position of the support vessel (as well as Heading and Course Over Ground which helps for navigation).

We were mostly interested in checking the integrity (and marine growth) of the lines and cable for this first job. Some USBL system is however planned for the next job to survey positions as well.

Thanks Eloi for the reply.


Can I ask, how did you give the overlay data to the Client, or were they happy enough with the raw video?

Also which screen recorder did you use?

Many thanks!!


Hi JonnyMarkD,

I have used the Xbox app as suggested by patrickelectric here:

It might be best to continue the specific discussion on screen recording within the above topic.

A specific reply for this job though: we provided the following to the client

  • Video from QGCl window only (with overlay) using Xbox app
  • We did not, but we could also have recorded the raw video in parallel using the QGC icon
  • Screenshots of the full screen (bottom bar with PC clock, QGC and OpenCPN windows) using one button on the Logitech controller: Taking screenshots with Logitech F310 - #9 by mateov
1 Like