Author Topic: HB 360 and underwater ROV's.  (Read 2190 times)

0 Members and 1 Guest are viewing this topic.

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
HB 360 and underwater ROV's.
« on: August 15, 2021, 09:24:29 AM »
As a diver it would be nice to know in advance if a diving spot is interesting enough to go diving, especially for locations at depths beyond 40 meter (> 130 feet).
ROV's (Remote Operating Vehicle) allow for pre-inspecting the areas of interest. However, there is a problem. The diver wants to anchor as close as possible to his new diving spot, found through the ROV.

Solution? To use HB 360 and marking waypoints on the location where the ROV is located at that particular moment. To boost the signal reflection to the transponder one could add/glue some stainless steel tape on the back of the ROV (of course, the weight of the ROV has to be recalibrated).

Does anyone have experience with HB 360 and following or locating ROV's, preferable at depths > 40 meter (> 130 feet).




Offline rnvinc

  • Hero Member
  • *****
  • Joined: Nov 2009
  • Location: Western KY
  • Posts: 4329
  • Unit(s): 1197c SI Combo, SOLIX G2 MSI
  • Software: Dependent on whim
  • Accessories: AS GRHA, MEGA 360, LowBird LSS 1 & 2
Re: HB 360 and underwater ROV's.
« Reply #1 on: August 15, 2021, 08:09:46 PM »
That’s an interesting concept  ...

Maybe some have tried this  ...

Rickie

Offline Rüdiger

  • Sr. Member
  • ****
  • Joined: Feb 2011
  • Posts: 493
Re: HB 360 and underwater ROV's.
« Reply #2 on: August 16, 2021, 03:42:32 AM »
Hej Peter

There are professional solutions to determine the position of a rov.

https://www.sar-unterwasser-systeme.de/uwis-unterwasser-gps-system/

But you could also mount a kind of radar reflector on an ROV or drone, this bundles and reflects the ultrasonic waves. As a result, the ROV or drone would be seen as a bright point on the 360 degree image of the HB and lead to the object of desire.
I haven't tried it myself yet, but it should work that way.

mvh
Rudiger

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
Re: HB 360 and underwater ROV's.
« Reply #3 on: August 16, 2021, 01:52:22 PM »
Hi Rudiger,

Thanks for the tip (and link). It looks nice.
And don't worry about your English. you did well. I myself am from Belgium and English isn't my first language either. By the way, I worked for many years in Basel and Konstanz.

The system you are referencing to is very expensive. If I could afford such level of equipment I wouldn't have HB.

I think that my solution for boosting the reflection beam by means of stainless steel tape/foil will not influence the moving characteristics of the ROV. However, a radar reflector will add a significant counter force and will increase drastically the CX-value (drag coefficient in liquid) of the ROV.

Your forum SOB looks great. For this link too, thank you.

Regards, Peter.

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
Re: HB 360 and underwater ROV's.
« Reply #4 on: August 17, 2021, 04:09:50 AM »
Hello oschi,

Thanks for your input. The boosting of the signal should be seen as "make sure that the signal (the 440 KHz beam) is reflecting", at least from a theoretical point of view. So don't spend any energy on that issue.

The type of ROV I am talking about is for example the Fifish V6 (or any other ROV of the same category, < 5000 €).

MEGA is of no interest. The ROV gives visuals that are way beyond the capabilities of MEGA. It is all about setting waypoint(s). In other words: where should I drop the anchor for a location that was "identified" as interesting by the ROV.

Knowing the depth shouldn't be a problem. The ROV is transmitting (by cable) its actual depth and shows it on the screen. Archeological artefacts are always found on the seafloor, hence once a waypoint is known a good approach of depth can be derived from the sonar after positioning the boat on the waypoint or nautical maps. The exact depth is of minor interest but can be established during diving (depth gauge/dive computer).


Offline Rüdiger

  • Sr. Member
  • ****
  • Joined: Feb 2011
  • Posts: 493
Re: HB 360 and underwater ROV's.
« Reply #5 on: August 17, 2021, 06:13:20 AM »
Hi Peter

I would let my ROV submerge on the anchor line of my boat, yet I don't have one. When you arrive at the anchor, steer the compass course to the object. Unfortunately, all tracking devices are really very expensive and currently still professional.

mvh
Rudiger

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
Re: HB 360 and underwater ROV's.
« Reply #6 on: August 17, 2021, 08:17:36 AM »
Hello Rudiger,

OK, nice try. But you speculate on the fact that one already knows the position of the artefact(s). As an example: anchor position and then straight South. But let's think a little "deeper" on this method.

In the Mediterranean (or any other ocean/sea) their is always current, for the Mediterranean it is often from the East. Therefore the ROV is pushed to the West although the compass of the ROV shows straight South. The ROV will end up somewhere South-West from the point that one originally targeted (like in aviation: they have the same problem when flying on compass).

Not only the ROV is exposed to the current. My operating depth is > 40 meter. This means that the tether of the ROV is at least 40 meters long. This adds yet another significant force on ROV, pulling it to the West (based on the above mentioned example). The current is pushing the ROV, the tether is pulling the ROV. 

In practice: the breathing gas stock (air, trimix) of a scuba diver is very limited, especially on depths > 40 meter. A diver can not spend time in searching and needs the anchor positioned as close as possible, let's say realistically +- 5 meter from the (potential) artefact.

Scenario: since I am looking for not-yet-discovered Roman and ancient Greek artefacts I first want to scan "visually" a larger area with the ROV. This can be done easily and relaxed on a sunny afternoon (with a beer!). On the assumption that I have a HB 360 installed AND that the ROV is visible on the 360, I would then see the ROV on my Solix 16 and can make a waypoint. Next day I could go to the waypoint, drop the anchor within acceptable limits and do an on-the-spot investigation while diving. In reality many POI's (Point Of Interest), after further investigation, do not result positively. Often it takes several dives to investigate a POI.

With a scenario like this my hit score will increase drastically where in the actual situation (without the ROV and a HB 360) my hit score, if lucky, is 1 POI on 100 dives. When speaking about positive resulting POI's I would say 1 on 1000 dives.

Offline Rüdiger

  • Sr. Member
  • ****
  • Joined: Feb 2011
  • Posts: 493
Re: HB 360 and underwater ROV's.
« Reply #7 on: August 17, 2021, 01:40:52 PM »
Hi Peter

I would first search with the sonar, then verify possible interesting places with the ROV and finally dive myself. If the visibility underwater allows it, a search with the tow camera would also be a good method. Then you can use the ROV for a fine search.

mvh
Rudiger

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
Re: HB 360 and underwater ROV's.
« Reply #8 on: August 19, 2021, 06:25:30 PM »
Hello Rüdiger,

It took me some time to define an adequate response.

If one is looking for clearly distinguishable POI's than you are absolutely right. Your suggested chronology should work just fine:
1) Side scan the area of interest. Identify distinguishable POI's. Make a waypoint on your Humminbird.
2) Verify by visual examination by means of the ROV.
3) Dive and investigate.

Remember: I'm looking specifically for amphoras in the Mediterranean Sea, ancient Roman and Greek pottery. We are talking about a time period of 2000 BC (Before Christ) to 500 AD (Anno Domini). Just for the record: Odysseus is somewhere in between (Trojan War, 1184 BC). After thousands of years on the seafloor all biodegradable material is gone, including most of the wooden structure of the vessel. Often the keel of a sunken vessel is to some extend protected against decaying because it is the first part that will be fully spared because of marine precipitation. 

Clearly distinguishable POI: in those days, when a vessel sunk all cargo (amphoras) shifted to the lowest part of the vessel. A vessel never sinks horizontally. These vessels had no compartments or any other architectural structure in the cargo room in order to divide or separate cargo, hence the cargo shifts during sinking to the lowest part. When touching the seafloor the result is a hump of amphoras and in the longitudinal axis some scattered remains (rubble/debris). The hump of amphoras is called in German archeological literature "ein Amphorenhügel". But due to thousands of years of sediment all that remains is a hump of about 1 meter of height. Therefore, a SI sonar should distinguish between a +- 1 m hump within a flat surrounding area of sand. With a Humminbird this is possible, even on operating depths > 40 m, on the condition of the level of experience on interpreting SI sonar signal, the sonar settings are appropriate and the surface conditions are optimal.

But my focus is on isolated amphoras (see section "Background to the nature of my initial question" below for more details). Nowadays, finding remains of a "not-yet-discovered" sunken Roman or ancient Greek vessel is quite impossible within the depth range of scuba diving. Since the 1950's millions of divers tried their luck and discovered all that was "discoverable". Isolated amphoras are extremely "camouflages" and therefore "yet-to-be-discovered".     

Background to the nature of my initial question: many captains in those days asked for a safe journey and offered amphoras to their gods (Neptune/Poseidon/...) upon departure. These amphoras are known in underwater archeological literature as isolated amphoras. After many thousands of years on the seabed they are fully covered with sand. As a matter of fact, due to wave movement they dig themselves in! A dedicated and well-trained diver's eye recognizes these POI's. These spots are characterized by for example a change of the structure of the sand (grains of sand), color of the sand, ripples in the sand (depending if the amphora is orientated horizontally to the seabed or if it has an angle), the presence of specific algea, ... After more than 40 years of diving and reading tons of abstracts, archeological articles and literature (Dutch, German, English, French) I have build-up a lot of expertise. With the actual sonar technology available on the market one will never be able to "see" those slightly changes of the sand or detect biological structures of a few mm, even in MEGA mode. Please read my note to oschi, quote: "MEGA is of no interest. The ROV gives visuals that are way beyond the capabilities of MEGA". And remember, the operating depth is > 40 meters.
     
So, in my case, the chronology should be:
1) Use the ROV's hi-res camera to identify POI's. The Mediterranean are clear waters. Quote previous reply: "This can be done easily and relaxed on a sunny afternoon (with a beer!)". "Lazing On a Sunny Afternoon", isn't that Queen ("A Night At The Opera")?
2) Use HB 360 attached to HB Helix/Solix and mark the waypoint, on the assumption that the ROV can be tracked by HB 360 unambiguously.
3) Anchorage at the waypoint and go diving to investigate.

This brings me to my initial question: can I make waypoints by using HB 360 in combination with HB Solix to track a ROV (e.g. Fifish V6) unambiguously (operating depth > 40 meters).

Offline Solixtude

  • Newbie
  • *
  • Joined: Jun 2019
  • Location: Tennessee
  • Posts: 1
  • Unit(s): 2 Solix 10s
  • Software: 3.4
  • Accessories: 360 Imaging
Re: HB 360 and underwater ROV's.
« Reply #9 on: August 20, 2021, 10:30:39 AM »
I've used the original HB 360 for three years and have just installed the MEGA 360 but have not used it yet.  I use these for fishing.  I have two Solix units for viewing.  Yes you can mark a waypoint on a spot you've identified with 360.  However, I don't think 360 will be a good option for what you have described.  It is a shallow water tool.   It doesn't work very well at depths greater than 30 ft.  For your purposes it might go as deep as 60 ft but you would not be able to see out very far from the boat.

Offline Peter

  • Jr. Member
  • **
  • Joined: Jun 2009
  • Location: Brasschaat, Belgium, Europe
  • Posts: 25
  • Golfe de Frejus - BYMS 22
    • Oxygen for Digital Diving
  • Unit(s): 1197c Si and Solix 16
  • Software: 4.750
  • Accessories: A boat !!!
Re: HB 360 and underwater ROV's.
« Reply #10 on: August 21, 2021, 05:41:07 AM »
Hello Solixtude,

Thank you for your input.

The opinion of a well experienced user on the HB 360 is of great value. You seem to confirm the specifications given by HB. My operational depths are below 130 ft (40 m). The good news is that you've mentioned that HB allows for setting waypoints.

The HB 360 was designed for fishing and is great for these applications. I think I have to wait for a couple of years and hopefully the HB 360 (or its successor) comes with deeper and wider spec's. Or maybe ROV manufacturers come with a HB-compatible location system (HB are great electronics. So, why not designing a ROV add-on and plug it into a HB).


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo

 

Related Topics

  Subject / Started by Replies Last post
8 Replies
7600 Views
Last post December 14, 2010, 03:12:40 PM
by sonar2000
1 Replies
4289 Views
Last post March 02, 2011, 01:27:14 AM
by RGecy
0 Replies
3393 Views
Last post January 17, 2012, 09:04:05 AM
by bigkahuna
7 Replies
7559 Views
Last post January 14, 2013, 08:33:07 PM
by cachristian
2 Replies
5425 Views
Last post October 25, 2013, 11:13:54 AM
by PaulB
6 Replies
5958 Views
Last post May 09, 2013, 09:49:27 PM
by promapper
0 Replies
5112 Views
Last post August 15, 2016, 09:04:49 AM
by bigkahuna
0 Replies
2053 Views
Last post January 20, 2018, 07:35:58 PM
by Skeeter07


anything
SimplePortal 2.3.3 © 2008-2010, SimplePortal