AIS Target Light Green or Dark Green

[Gilletarom]

Hello,

Here a screenshot during playing a VDS recorder file.

You can see that there is some target light green and some target dark green.

On this page, nothing ...about this. : AIS | Official OpenCPN Homepage

What about ?

Thank by advance.

[cagney]

I would call the color "grayed out" green. It is described in the wiki, although the picture there illustrates a grayed out "yellow" target.
Both means

Ship which has lost fix - position unavailable. Displayed at the last known position.

I will clarify this a bit in the wiki, so that misunderstanding is avoided.

Thomas

[bdbcat]

Gilletarom...

The targets which are dark green ("Concorde" in your posted image) are detected as targets complying with the Euro AIS Inland specification.

https://en.wikipedia.org/wiki/Automa...ication_System

This is not documented in OpenCPN (yet).

Dave

[Gilletarom]

Merci Thomas, Merci Dave .

Thank you. I will introduce your explanations in opencpn.shoreline.fr web site.

[cagney]

So much for my advice....

Thanks Dave, for the info.

Thomas

[Gilletarom]

Hello Dave,

Apart from the color, which is a choice to own OpenCPN display, what allows the information issued by the boat, know that is part of the vessels operating in inland waters?

B.R. Gilletarom.

[cagney]

I wonder what the real meaning of dark green is. I have seen a few targets that have nothing to do with inland waters. Is it a question of having an AIS unit to a certain standard?

fishing.png Views: 183 Size: 15.2 KB ID: 64917" style="margin: 2px" />

Why is this fishing-boat dark green?

And what about this well known vessel?




Thomas

[bdbcat]

Thomas/Gilletarom...

Inland Euro is signified if we receive the following:

AIS Message Type 8 (binary data)
Designated Area Code (DAC) = 200
Functional Identifier = 10 (Inland static data)

See the following document:
http://www.ccr-zkr.org/files/documents/ris/ais101_e.pdf

I'm sure Marco could amplify on this....

Thanks
Dave

[Gilletarom]

I, like Thomas, very skeptical about the boats shown in light green and dark green. I have hundreds of boats navigating the canals of the Netherlands, which appear bright green. And I have a few boats that appear dark green.

Should we consider that:
- Almost all boat captains do not know documenting their AIS software
- OpenCPN does not work well?
B.R. Gilletarom.

[bdbcat]

Gilletarom....

No reason to be sceptical. The target will be dark green in OpenCPN only if the ship chooses to transmit the "Inland Static Data".

So far as I can tell, Inland AIS is optional in the EU at this time, but may become mandatory in the future, in some countries. This will require a software update to the ship's transponder, so we can expect some ship operators to lag behind. There is also some debate on privacy issues among the ship captains....

I am not surprised that it is not widely used, so far.

Here is a nice document (English, I'm afraid) that talks about Inland AIS. Please note, by the way, that the AIS target query info images shown in the document come from, you guessed it, OpenCPN

http://ris.vlaanderen.be/documents/l...nalversion.pdf

Dave

[cagney]

I'm not "skeptical" about targets with different shades of green. I just wasn't aware of this feature in O, nor of the exact implication. OpenCPN must just try to show the existing targets as close to standards as possible.

There are no problems showing abuse of the AIS standards. A target that is really just advertising, an anchored target doing 15 kts or a pilot boat showing "Constrained by draught" signal for example. Then there is obviously some vessels equipped with an unnecessary complicated AIS set. I'm thinking of the fishing boat in my post above.

So what? I suppose we just have to get used to it. In any case it has nothing to do with O.

Thomas

[Gilletarom]

hello,

Thank. I can update the shorelinefr website.

[Gilletarom]

Hello Thomas,

I had not played the file navigation in the IJ kanal (Amsterdam Ijmuiden in the Netherlands) and the Canal Zaamdam.

I realized that he has a lot of inland vessel type. Its size is too big (1.5 MB once zipped). So I can not put it as an attachment.

I just gives you a screenshot. You can use it in wiki.

B.R. Gilletarom.

[MAS3]

Originally Posted by bdbcat

So far as I can tell, Inland AIS is optional in the EU at this time, but may become mandatory in the future, in some countries.
This will require a software update to the ship's transponder, so we can expect some ship operators to lag behind.

AIS is mandatory in Austria since 2008, and skippers transmitting incorrect data like in the examples will get in trouble (fined).
In Belgium it's mandatory in sea ports like Antwerp.

Inland ships are only allowed to use inland AIS, but it seems that some brands of AIS equipment are transmitting SOLAS data too (which has not been entered because it becomes unavailable once the equipment is set to inland).

Also, a lot of these ships use chartplotter software to program the AIS, and there's quite some problems with that resulting in incorrect data being transmitted, like incorrect ship types or operation modes.

Software updates are only required in case the regulations are changed since they became "final", or for software that should have never been approved.
That is the largest problem with all this.
The equipment has to be re-approved, software updates installed and documented.
This means all parties involved (government, manufacturers, installation companies and the skippers) have to do work that they will want to be paid, but who's going to do that ?
Especially because not everything was known or taken in account while drafting the regulations.