AIS icon

[bcn]

Dirk,

understood - remains the question about mutex with the Class A status?
So what about ( question mark might be more prominent perhaps):

[CarCode]

Originally Posted by rooiedirk

Hubert,
A blue flag (now a days not a flag anymore) is used on rivers. when you go up river you would like in bents have the inside where there is less current. So if the river turns to the left you set a blue signal to indicate that you want the portside af the fairway and meet traffic starboard to starboard. So in practice you crossing the fairway very often.
If you are going down and see a upgoing vessel showing the blue vlag, you 'anwer' by setting also the blue flag, meaning you understood and will pass accordingly.

The blue cones is a total different story. The cones are telling that the vessel is transporting dangerous cargo. Where:
1 cone means flamable cargo
2 cones poison cargo
3 cones explosive cargo
Depending of the number of cones there are multiple safety rules as distance to stay free etc.

So the blue flag is changing a few times per hour depending of the curving river, and the cones are changing with the cargo/voyage

Correct.
The first proposal of a square sign doesn't work (see below).
A ship sign should be a ship sign. If really needed make the whole sign another colour.

Gerhard

[rooiedirk]

How about something like this??
Dirk

[fgd3]

Originally Posted by rooiedirk

Dave,
No the barge's SOG was 0. And therefore its COG anything.
...
If in my example the barge would have being plotted as 'no heading available', I wouldn't have thought it was on a Northerly heading, and in my radio conversation I would have said "I will pass south of you" instead of "I will pass your stern".

If a target is not moving why do you care about its heading? Isn't this issue resolved much more simply by changing your communication habits as you described? Just say "I will pass south of you" and there is no ambiguity. No need to change the program at all.

It's useful to have the triangle icon for AIS (non-AtoN) targets. It makes vessels stand out on the display. It's easy to tell they are not moving if they have no course predictor.

Even if a vessel is under way do we care about its heading or just is COG? Isn't heading only of interest to us because it is a quick shorthand approximation of COG?

If you are just trying to comply with the EU's ECDIS standards you have to give up the triangle ship icon:

"Information regarding the position and orientation of other vessels, gathered by communication links like AIS, shall be only displayed if they are up-to-date (nearly real-time) and accurate. The position and the orientation of other vessels by:
--a directed triangle, or
--a true outline (to scale),
shall be not presented if the heading of these other vessels is not available. A generic symbol is recommended."

from EUR-Lex - 32013R0909 - EN - EUR-Lex

Should you want to do that the octagon icon used in the standard looks like a good choice.

How important is compliance with those standards?


Fabbian

[rooiedirk]

Fabian,

Tis will be most important for inland-AIS. Only a few years ago there was the inland skippers were very annoyed because a new law made it compulsory to have a compass and chart onboard. They are onboard now but often hide away in some locker.
If you ask a average inland skipper what direction is South, the answers will be more or less the same as asking the question to an average car-driver.
We are talking inland in terms as port to port etc.
The course predictor is not always visible. Depending on scale and SOG of target.
My point is that it is easy to be confused by thinking the target has a north heading while it could be anything.
And a heading even at zero speed does matter. I wouldn't pass close to a vessel's bow even if it doesn't move. (Keep in mind the AIS transmit interval at zero speed goes up to 3 minutes. In 3 min a lot can change)

But it is not to difficult to make a possibility to switch it off.

[bcn]

Originally Posted by fgd3

"Information regarding the position and orientation of other vessels, gathered by communication links like AIS, shall be only displayed if they are up-to-date (nearly real-time) and accurate. The position and the orientation of other vessels by:
--a directed triangle, or
--a true outline (to scale),
shall be not presented if the heading of these other vessels is not available. A generic symbol is recommended."

from EUR-Lex - 32013R0909 - EN - EUR-Lex

Should you want to do that the octagon icon used in the standard looks like a good choice.

How important is compliance with those standards?


Fabbian

The compliance - even in the weak sense like above ("is recommended") which might be in contradiction with the sentence before "shall not" - is important for our European Inland Water user community, which is quite numerous and relies on OCPN for their daily work.

We are striving to be able to emit a " Certificate of Conformity " in order to allow to maintain support to this people.

This is the background of the feature request for InlandECDIS.

Hubert

[fgd3]

Originally Posted by rooiedirk

Fabian,


And a heading even at zero speed does matter. I wouldn't pass close to a vessel's bow even if it doesn't move. (Keep in mind the AIS transmit interval at zero speed goes up to 3 minutes. In 3 min a lot can change)

Thanks for trying to explain the issue more fully. There are still some things I don't understand.

I wouldn't pass close to a vessel at all based just on the AIS target plotted on my chart. In my experience AIS just doesn't update fast or frequently enough for real time maneuvering. Wouldn't you have the vessel in sight before you had to decide whether to pass ahead or astern? Wouldn't that reveal its heading? Wouldn't you assess its speed when you saw it, rather than relying on (possibly out dated) AIS data?

If a vessel is close enough to you that you are concerned about how to pass it wouldn't you zoom your chart display so its course predictor would be visible, if it had one? And if it didn't, because it wasn't moving, wouldn't all the choices about how to pass be yours alone, to be taken in your own time?

Fabbian

[bcn]

Dirk,

trying to play with the no-heading indicator. Perhaps a cross-out would be easier to spot than a "?". And the question mark might be seen as "an unknown symbol".

Making this switchable either within an InlandECDIS context or as an addtional setting (yet another setting )

Hubert

[bdbcat]

bcn...

I think we will need an options setting to switch to the "Inland ENC Info Mode". Otherwise we will need to teach a lot of people in the US about new symbols which may not be intuitive, and will be certainly be different.

The US is the land of predominantly AIS-B, with no HDG info available.

And there will be other specific display details for this mode, I'm sure.

So, the generic AIS octagons for Inland ENC mode may be OK.

Dave

[bcn]

Originally Posted by bdbcat

bcn...

I think we will need an options setting to switch to the "Inland ENC Info Mode".
Dave

What would be great to get the "dawn" and "Standard screen content" at start-up under the same umbrella.

Plus the other goodies mentioned in the feature request (waterwayAxis up and WaterWay km/mile)
The latter should be useful at the other side - yours - of the pond as well.

[bcn]

Might result in:

[rooiedirk]

Having an Inland Switch witch would change:

1. AIS sybols
2. startup in dawn mode
3. switch to the use of inland chart (iENC)
4. change to head or even better waterway axis up
5. switch some plugin in/out
6. show the fairway Distance mark of current position in a dashboard like instrument
7. Showing the local navigational info( local VHF channels, VTS area etc)
8. Showing extra info like water levels (plugin?)

Most of this list is not to difficult. I think we would need a special config file for inland, swapping the config files with the inlandENC switch.
Point 1 and 2 I could do.

Points 3, 4 and5 would be covered by the config file swap.
6, 7 and 8 could be done in plugins, that would be loaded/unloaded by the config swap.


Shoot


Dirk

[bcn]

Dirk,

1,2 and 3 are the main steps for compliance with the InfoMode.

The Watchdog-PI to signal missing data inputs might be required as well.
Plus the Draw-PI in case safety contours are required.

If we get those into the 4.5 (and then the 4.6) as an OCPN mode then we will contact the German authorities. We have some contacts already.

And with their guidance propose to provide a "Certificate of Conformance" so that the skippers have a paper in their hands when questioned by the gentlemen who are entitled to ask and to hand out costly tickets.

Hubert

[rooiedirk]

Hubert, Dave,

I could do some coding fore inlandECDIS.
At the moment my thoughts are going in the folowing direction:
At the Option-User Interface add an option: use alternetive configuration. with an dropdown ctrl with possible .conf files.
add an option to the OpenCPN.conf "UseConfigFile=OpenCPN_I_Ecdis.conf"
At startup first check if there is a "UseConfigFile" and if yes change the used configfile for the wanted one, and continue with startup.
Add a readonly option to for the config "ForcedStartupScreenMode=dusk"
at startup try to read above option en act accordingly.

In this alternative conf file you could do everyting you can withing O. Point to right set of charts. Set units to km. etc.

For the AIS I'm considering of switching off the native O AIS en load an plugin with inland AIS. This would safe a lot off fiddling on O's code. (perhaps the OpenCPN AIS code should be shifted to a plugin also??)

The advantage of this aproach is that it could be used for something totaly different just as easy. You could use different configurations for captain and mate for example.

So far my thoughts up to now.