AIS Targets Disappear After a Longer Period

[LeaseOnLife]

Hi Tore

I tried a few things to replicate your scenarios, ( I only have XP).

I did find a few things:

The AIS target list keeps the targets longer than the timeout settings in opencpn/toolbox/AIS/"lost targets". I simulated your problem by turning off the AIS receiver. After the time for "Remove lost targets after" has gone by, the AIS targets on the chart disappeared, but many were still on the AIS target list. Several minutes later the target list was empty.

All this points to your Opencpn ignoring your AIS stream after some time has gone by.

It is not the drawing layer, it is not a problem between target list mismatch to number of targets on the chart.

So, something makes Opencpn "deaf" in your Vista-setup.

I also played your 1hr AIS recording many times to my setup, but Opencpn never failed....

I am pretty much out of ideas, well, maybe one more thing to try:

When the targets have disappeared, instead of restarting opencpn, go into toolbox, AIS, and change the AIS data port to none, press OK. Then go back into toolbox, AIS, and change the AIS data port back to your original settings. Do the targets show up again?

Dirk

[sinbad7]

Hi Dirk..

Thanks for testing.. It seems like OCPN does not renew the targets once received,and after a while deletes all the 'dead' targets.

Switching the COM: port from None and back to COM:5 did not produce any targets.
Resetting OCPN displayed the targets again.

I was deliberating another possibility,could it have something to do with the 'save screen' facility in Vista? Perhaps OCPN translates this as end of datastream?

As I said,it works perfectly in Fugawi and the collected datastream.

Tore

[LeaseOnLife]

Hi Tore

Interesiting!

To verify your screensaver theory:

Can you run Fugawi and OpenCPN at the same time?

If not, maybe we can set you up to do so. It would be interesting if Fugawi keeps showing AIS targets while OpenCPN quits to do so, at the same time, after windows wakes up from a screensaver.

There are several ways of splitting a COM port into multiple COM ports to feed it to several program.

So.... Are you running Fugawi and OpenCPN at the same time?


Dirk

[fgd3]

Originally Posted by sinbad7

I was deliberating another possibility,could it have something to do with the 'save screen' facility in Vista? Perhaps OCPN translates this as end of datastream?

Tore

Can't you test that by turning off your screen saver?

Fabbian

[sailorF54]

FWIW

I've had some success suggesting to French users complaining about GPS/AIS dropping out on Vista to modify items in the 'electric supply panel' parameters, namely 'advanced settings' / 'USB parameters' / 'selective suspension' / 'on batteries' : disabled - 'on power line' : disabled

(Sorry, poor back translation from French-localized Vista)

[sinbad7]

My theory regarding the screen saver is invalid as it appears i never engaged the screensaver.

1. OCPN after a period deletes ALL targets,needing a reset to bring them back.
2. Fugawi maintains ALL targets continuously.
3. AIS Despatcher continuously collects he AIS data without stopping.

Must be some malfuntion in the OCPN algorithm.

Tore

[sinbad7]

SailorF54..

Interesting theory. I will try it out and revert with results.
But would that event not also affect the Fugawi targets?

Tore

[sinbad7]

Sailorf54..

Tested your suggestion about current supply to the USB but still not working.''

Tore

[sailorF54]

Originally Posted by sinbad7

Sailorf54..

Tested your suggestion about current supply to the USB but still not working.''

Tore

Sigh.....

[dacust]

Originally Posted by sinbad7

My theory regarding the screen saver is invalid as it appears i never engaged the screensaver.

1. OCPN after a period deletes ALL targets,needing a reset to bring them back.
2. Fugawi maintains ALL targets continuously.
3. AIS Despatcher continuously collects he AIS data without stopping.

Must be some malfuntion in the OCPN algorithm.

Tore

You may have said this somewhere, but I don't remember seeing it:

For #1, Does OpenCPN update new locations up until the point they disappear?
For #2, you say it maintains the targets. Does it update them with new data/locations/headings/etc.?

My thinking is, maybe it's possible that you are loosing communications. OpenCPN is cleaning up the screen while Fugawi is not.

-dan

[sinbad7]

Dan..

#1 OCPN updates the targets while visible.
#2 Fugawi updates the targets continuously.

Running AIS Despather for a long period gives continuous NMEA mesages without breaks.

Read also my #60

Tore

[Pimblokland]

Hello, I have the same problem. Using Windows 7, now back to the stable version 2.5.0 with the CTRX AIS transponder. With the programm "Cahrt Navogator Pro" from Maptech it woked fine. With OCPN the AIS information dissapears. And even OCPN stopped working after I clicked on "AIS Object list". It damaged the programm. I had to reinstall Open CPN. This happened more than once.

Can anyone tell me what the solution is? Or is OPEN CPN not yet ready for use at sea?

I am a dutch sailor, now cruising in the Carribean, and crossing the Atlantic back to Europe this year in May. A stable navigation programm is a must! AIS information is to important. I must be able to rely on it.

Pim Blokland

SY LINEA

www.sy-linea.com

[sinbad7]

Pim..

You should upgrade to the latest v. 2.6.1511 which has most of the errors corrected.
However,all AIS targets still disappears after a while. Doing a re-start receives the targets again. Obviously some mis-enterpretation in the algorithm reading the NMEA source. There can be long periods between messages,perhaps they are read as end of messages? No one seems to pay much attention to this,potentially dangerous fault. My NMEA source works continuously without fault with both AIS Dispatcher and Fugawi ENC Marine.

I am sure someone will look into this pretty soon and fix it.

Tore

[Pimblokland]

Originally Posted by sinbad7

Pim..

You should upgrade to the latest v. 2.6.1511 which has most of the errors corrected.
However,all AIS targets still disappears after a while. Doing a re-start receives the targets again. Obviously some mis-enterpretation in the algorithm reading the NMEA source. There can be long periods between messages,perhaps they are read as end of messages? No one seems to pay much attention to this,potentially dangerous fault. My NMEA source works continuously without fault with both AIS Dispatcher and Fugawi ENC Marine.

I am sure someone will look into this pretty soon and fix it.

Tore

Thanks Sinbad,
I noticed that you can get the AIS ships back, just by unplug and plug in the USB connector of the AIS device. No need to restart.
I am now in St. Martin, very much AIS transponding ships. Therefore the ships disappear withing 10 minutes. Maybe to much information?
But still it gives no solution...

Pim

[cagney]

Originally Posted by Pimblokland

Thanks Sinbad,
I noticed that you can get the AIS ships back, just by unplug and plug in the USB connector of the AIS device. No need to restart.
I am now in St. Martin, very much AIS transponding ships. Therefore the ships disappear withing 10 minutes. Maybe to much information?
But still it gives no solution...

Pim

Add the sentence

DebugNMEA=3000

To your ini file, close down OpenCPN first.
Please download the VDR - voyage data recorder. Record about 30 min or longer (as long as possible!) of your AIS traffic . Publish the resulting file.
Publish your log file.

Tore ! The same data from your end would be good as well.

This may just help the developers to pinpoint the problem.

Thomas