Mayday Position on OpenCPN Screen?

[Gilletarom]

Hello Dave, Hello all developers,

Hello Dave, Hello all developers

I ask for a development.

My GPS is connected to my VHF. My radio sends the position of my boat OpenCPN. This is what allows OpenCPN placing my boat in the right place on the map.

When a mayday is launched by another boat, my radio displays the position of the boat on the screen of my VHF.

I suppose there is a NMEA sentence that transmits this position OpenCPN.

Is it possible that OpenCPN immediately displays the ship in danger on the PC screen


Thank you in advance if anyone can implement this in OpenCPN

B.R. Gilletarom.

[Gilletarom]

Add : I thing that the NMEA sentences generated for this purpose are DSC and DSE.

DSC,xx,xxxxxxxxxx,xx,xx,xx,x.x,x.x,xxxxxxxxxx,xx,a ,a*hh
Format Specifier
Address
Category
Nature of Distress or First Telecommand
Type of Communication or Second Telecommand
Position or Channel/Frequency
Time or Tel. No.
MMSI of ship in distress
Nature of Distress
Acknowledgement
Expansion indicator


DSE,x,x,a,xxxxxxxxxx,xx,c--c, .……… ,xx,c--c*hh

Total number of sentences
Sentence number
Query-Replay flag
Vessel MMSI
Data Set
Additional data sets
Data set

[cagney]

Gilletarom

O does already handle DSC & DSE.
See page DSC and Buddy via AIS. | Official OpenCPN Homepage

Try this file (delete .pdf) in the VDR plugin dsc.txt.pdf
Check the icon in Japan. No alarm is generated, however.

Make sure that OpenCPN is receiving the correct sentences from your VHF.

Thomas

[Gilletarom]

Hello Thomas,

Thank you for this file test.

I had not imagined that it would have been with the AIS. I will update the tutorial opencpn@shoreline.fr about it.


That said, I expect a stronger demonstration of the ship in distress. with:
- A centering of the screen on the boat,
- The immediate creation of a temporary road between my boat and the boat in distress
- Displaying the distance to join and given my speed, the probable duration of the course.

Indeed, the arrival of such a message is accompanied by VHF, a request for assistance. Take the decision to offer our help or not to offer.

The information I want on the screen, would be a decision support.

B.R. Gilletarom.

[cagney]

All emergencies reaching O needs to be treated the same.
A DSC emergency should be treated the same way as a SART transponder emergency, which is treated like this:



The alarm is set of. A dialog pops up informing the user of an emergency.
Notice the jump to button. It must be up to the navigator if he wants to view the emergency target, not OpenCPN. To do this automatically could be dangerous.
To quickly create a route to the distressed "object", "Jump To" and then right-click on the target + "Navigate to here".

Thomas

[PjotrC]

I could _maybe_ live with the dialog and the "Jump To" button, but definitely not with an OCPN alarm going off on receiving a DSC DISTRESS. The alarm is already ringing on the radio set and it has to be acked there manually, and a specific radio procedure has to be followed there, so just let OCPN continue ... All I would add is a log entry.

Generally I like when software helps me when I need help, but not when it forces me to do things immediately. Thomas is right in saying that too much automation in good faith can be counterproductive. Typical case is MOB handling.

[Gilletarom]

Originally Posted by PjotrC

..

All I would add is a log entry.

Ineffective for me to deal with the emergency.

I return to the procedure proposed by Thomas. Too long to implement. Too error-prone.
Failing a command line in the context menu should allow visually understand immediately where the boat is in danger.

B.R. Gilletarom.

[PjotrC]

Originally Posted by Gilletarom

Ineffective for me to deal with the emergency.

Gilletarom...

Contrary to AIS SART, DSC distress procedure should be effective even without any support from the chartplotter.

I agree it might be difficult for a user who has no AIS receiver installed and thus had no opportunity to become familiar with using AIS Target List. But an extra alarm, extra dialogs etc. might actually distract the operator, doing more harm than help... I think it is far better to focus on the radio and use simple tools then...

Piotr

[Gilletarom]

It seems to me that I did not explain my request. It is based on our personal experience on board our ships, using the VHF AIS DSC and a micro computer using OpenCPN.

When the radio triggers an alert corresponding to a "Maiday" must:
- Evaluate the position of the boat in danger
- And:
Either decide to offer our intervention
Or decide not to intervene

This summer along the coast of Netherlands and Belgium, we had very little warning. But in Britain, where we usually sail, we alerts several times a day. Some alerts for a boat in danger near us. Other alerts for boats very very far from us.

When the sea is calm, it is not difficult to look on the screen with the mouse OpenCPN.
This is much more complicated when the wind is strong and the sea is rough. In this case, it requires a substantial effort on our part.

If I understand correctly, from the 322 version OpenCPN displays a red diamond to show the boat in danger. We do not know. And this summer, during our sailing, we have not seen these diamonds when boats have asked for help.

If the boat is in danger close to our position, we can be without having to zoom out or do a search to see the screen. If the boat is off, it will do a search on the screen to locate.
If the sea is calm, no problem.
If the sea is rough, it is much more complicated. Do not forget that our equipment is not professional equipment assistance and research at sea

That's why I want OpenCPN provide effective support and as simple as possible to locate the ship in danger on the screen.

I suggested that the screen is automatically centered on the boat in danger, I have proposed a temporary route is in place ... But this may be something else.

At a minimum, I hope a message displayed on the screen giving the distance and heading to join the ship in danger.

B.R. Gilletarom.

[cagney]

If I understand correctly, from the 322 version OpenCPN displays a red diamond to show the boat in danger. We do not know. And this summer, during our sailing, we have not seen these diamonds when boats have asked for help.

Gilletarom

The red diamond on receiving an emergency via NMEA DSC & DSE, has been in OpenCPN since version 3.0. So why didn't you see it? If it's just a normal DSC transmission the diamond will probably be yellow. Do you have any VDR recording from a time when you have received a DSC?

Thomas

[Gilletarom]

Hello Thomas,

I do not know OpenCPN displays a red diamond from 3.0. You learn me. Yet, I often looked in the wiki. It seems to me it is explained for a short time. (Note that I do blame anyone).

Therefore, when we receive an alert, we never looked at the screen OpenCPN.

I have many VDR files. I even tried to replay those we record this summer. I have not managed to find the alerts. But I must say that my files last very long, more or less a day of sailing every time. Even accelerating reading and zooming out, I have not managed to see red diamond. Lack of patience and attention from me? It's possible. It is necessary to do it again.

In it reflective, if Gilletarom, using OpenCPN for almost 4 years, never managed to see the red diamonds, imagine what it can be other more novice users.
In general, I am at the tile of the boat. And this is my wife who looks at the screen. She practices a lot less than I OpenCPN. I can not blame him for not seeing the red diamonds. It is even one of the reasons that prompted me to start this thread on the cruisers forum.

B.R. Gilletarom.

[cagney]

Gilletarom

There is no need to play through all your VDR files. Just open the files in a text editor and search for DSC and DSE, then copy the lines you find to a new file. Play this file in the VDR plugin.

The DSC feature was first documented in 3.0 and developed in the 2.6 beta series.
http://opencpn.org/ocpn/downloads/doc/3.0_Manual.7z
OpenCPN 3.0 Release Announcement | Official OpenCPN Homepage

But who can keep track of everything in O nowadays?
Compare what I first said about the inland targets

Thomas

[Gilletarom]

Hello Thomas,

Yes, I see that "DSC" appears in the wiki version 3.0. Effectively. But I could not understand at that time that the "DSC" possible to identify vessels that send a "Mayday" ... And as it had been developed within the wiki ...

Furthermore, I just always find in my recorded with VDR files this summer, the presence of phrases "$ DSE" type "$ DSC"! "DSE"! "DSC", "! CDDSE" "! CDDSC ".

I have not found any. As if VDR did not record these phrases or the like if the radio does not send these statements to the PC.

For the VHF is a Navicom RT 550 DSC AIS. I do not have a list of NMEA sentences transferred under the eyes.

For OpenCPN, I just look at the options. And in particular the connection used. Phrases DSC or DSE types are not part of the list automatically accepted by OpenCPN ....

See the screenshot attached below.

It would probably have been that I added with the "Add" command. I did not. Besides, I just discovered the existence of these NMEA sentences, a few days ago.

These are the sentences they automatically accepted?

B.R. Gilletarom.

[Gilletarom]

Question :

VDR read "DSE" and "DSC" sentences but do it record this sentences ?

[Gilletarom]

I just found the documentation VHF RT 650 which is almost the same as the RT 550.

It seems that the list of NMEA sentences transmitted either:

GLL, GGA, RMC and GNS.

Therefore, DSC and DSE sentences kind would not be transmitted. This would explain why VDR does not record.