Technical support

by Tihomir Makovec

I am a senior technician and head of the professional divers at Marine Biology Station Piran, National Institute of Biology, Slovenia. I have been collaborating with Prof. Monika Bright from the University of Vienna for many years and assisting her during her yearly field work stays at Marine Biology Station Piran. I was invited to participate in this expedition as technical support to the scientific team. During this cruise I am responsible for the water sampling system that we attach to the ROV SuBastian before every dive. The system was developed at the NIOZ under the supervision of Dr. Sabine Gollner in collaboration with Prof. Monika Bright. Prior to the cruise, we tested the water sampling system in the coast in front of our institute in Slovenia and later also in Netherlands. The whole water sampling system consists of 4 main units: a blue bag, a pump, a switch with two levers and a system of plastic pipes. This sampling system can be connected either to the MBSG box or to the metal tube with a handle connected to the bag, which basically can hold 75 L. This way, ROV pilots can easily collect water samples from a precise location (holes, pits, cracks) with the hydraulic arm. At the end of the dive, we transfer water samples from the bag into containers, prepared in advance by researchers, for each different experiment. Afterwards, we replace the used tubes with new ones, we change the bag and the batteries that are in the switch assembly.

(Left) Monika Bright and Tihomir Makovec. Attribution: Teresa Winter (CC-BY-NC-SA 4.0) (Center) Testing MBSG. Attribution: Teresa Winter (CC-BY-NC-SA 4.0) (Right) Mesh Box Staining Gadget, attribution: Tihomir Makovec (CC-BY-NC-SA 4.0)


We need to make sure that everything is attached to the ROV in such a way that handling its hydraulic arms is accessible, easy, and safe to prevent damage or malfunction of the ROV. Before the ROV is again lowered into the water, all pipe systems must be filled with water, because the air or gas bubbles that are compressible under pressure can disable or damage the operation of the pumping system. Everything must be adapted to work under high pressure, which at a depth of 2500 m is 251 bars or 25100 kPa.

-What happens when something does not work?

First you must look why this didn't work. Why didn't it work? Don't panic. Maybe it is just without fuel, or battery. Maybe is something simple, as just to connect it to the electricity. First you look at the basic things that the machine needs to work. If, after checking this, it still doesn't work, then you try check the things that everybody can check, that don't require a specialist. So, it can be a broken cable or that some software didn't work. Then you try to repair this. Usually, you acquire this capability through experience. When you have a lot of experience, you often recognize why something went wrong. And then, you try to fix this. But when you can't fix it, YOU MUST STOP! And then take a break, and try to look from the opposite direction. So, maybe, maybe ... it does not work because of something that you never thought of.

(Left) The big blue bag, on SuBastian. Attribution: Salvador Espada (CC-BY-NC-SA 4.0). (Right) Starboard hydraulic arm of SuBastian operating the MBSG switch levers. Schmidt Ocean Institute (CC-BY-NC-SA 4.0)