Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 29-07-2019, 06:43   #1
lsk
Registered User

Join Date: Jul 2019
Posts: 6
Add second GPS object to openCPN

Hi,
I'm in need of showing another object (in addition to my boat) in OpenCPN.
At the moment I wrote a little proxy server that translates GPGLL sentences in AIVDM, so I can plot the second object on the map as AIS target, but since I'm not a developer, it's painfully slow (one sentence every about 20 is translated, the other just lost...), and I'm quite sure there's a better method to achieve that.

Anyone has any idea?

Thank you
__________________

lsk is offline   Reply With Quote
Old 29-07-2019, 11:31   #2
Registered User

Join Date: Nov 2012
Location: Orust Sweden
Boat: Najad 34
Posts: 2,515
Re: Add second GPS object to openCPN

lsk..
One method used for several similar purpose is to transfere the information from xxGLL to a xxTLL message.

OpenCPN will understand that as an ARPA target using the same functionality as for AIS targets.
You can have a general Target number, e.g. 01, and a name, e.g. "My target" and fill with the position from xxGLL on every update.
Set Status to "T" and nothing in the "Reference" field.
Code:
TLL - Target Latitude and Longitude
Target number, name, position and time tag for use in systems tracking targets.
$--TLL,xx,llll.ll,a,yyyyy.yy,a,c--c,hhmmss.ss,a,a*hh <CR><LF>
Attached Thumbnails
Click image for larger version

Name:	TLL.JPG
Views:	55
Size:	60.0 KB
ID:	196829  
__________________

Hakan is offline   Reply With Quote
Old 01-08-2019, 17:13   #3
Registered User
 
rgleason's Avatar

Join Date: Mar 2012
Location: Boston, MA
Boat: 1981 Bristol 32 Sloop
Posts: 13,302
Re: Add second GPS object to openCPN

I added that to FAQ


Is there any way that nmeaconverter would help with changing the GPS to TLL? Does it read connection priorities? Maybe not because it is a plugin of opencpn?
rgleason is offline   Reply With Quote
Old 02-08-2019, 01:05   #4
Registered User
 
rooiedirk's Avatar

Join Date: Aug 2010
Location: Netherlands
Boat: Oneoff
Posts: 407
Re: Add second GPS object to openCPN

Indeed translate your second GPGLL to xxTLL is much easier then translating to AIVDM.
Unfortunally I don't see a way to use the nmea-converter plugin to do the job.
Attached Thumbnails
Click image for larger version

Name:	Screenshot_20190802_095857.png
Views:	45
Size:	76.1 KB
ID:	197057  
__________________
Navigation is know where you are and what to do to get where you want.
But also: Know where you don't want to be and what to do to don't get there.
rooiedirk is offline   Reply With Quote
Old 02-08-2019, 16:46   #5
Registered User
 
yachtvalhalla's Avatar

Join Date: Aug 2009
Location: Philippines
Boat: Fuji 32 Ketch
Posts: 817
Re: Add second GPS object to openCPN

Quote:
Originally Posted by lsk View Post
Hi,
I'm in need of showing another object (in addition to my boat) in OpenCPN.
At the moment I wrote a little proxy server that translates GPGLL sentences in AIVDM, so I can plot the second object on the map as AIS target

Thank you

It might be my early morning brain not awake yet but are you trying to put AIS targets on the screen?


That's done with OpenCPN as a normal feature.


Terry
__________________
VALHALLA's Mooring Page
yachtvalhalla is offline   Reply With Quote
Old 04-08-2019, 00:33   #6
Registered User
 
rooiedirk's Avatar

Join Date: Aug 2010
Location: Netherlands
Boat: Oneoff
Posts: 407
Re: Add second GPS object to openCPN

Something comingup my mind.
If you can configure your 'first' GPS not to send a GLL sentence, and your 'other' does, then the only incomming GLL sentence would be from the 'other'.
Then if you tell OpenCPN not to use the GLL sentence for the ownship position by adding "UseNMEA_GLL=0" to the config/ini file.
Then you can use the nmeaconverter plugin to convert the GLL to TLL. No external programs and servers needed anymore.
__________________
Navigation is know where you are and what to do to get where you want.
But also: Know where you don't want to be and what to do to don't get there.
rooiedirk is offline   Reply With Quote
Old 04-08-2019, 16:45   #7
Registered User
 
rgleason's Avatar

Join Date: Mar 2012
Location: Boston, MA
Boat: 1981 Bristol 32 Sloop
Posts: 13,302
Re: Add second GPS object to openCPN

Dirk, I think your idea should be written up once, someone proves it works. I like it!
rgleason is offline   Reply With Quote
Old 10-08-2019, 05:21   #8
Registered User

Join Date: Apr 2010
Location: Newport News VA
Boat: Egg Harbor sedan cruiser 1970
Posts: 901
Re: Add second GPS object to openCPN

Except how many people will know how to configure a gps to not send a sentance? Or even change anything a GPS does send out, few and far between I think.

I could imagine since GPS has a Rx wire, it can be done if you have the right software and know the right command format. And how many people have that.

So IMO, for practicality reasons, that solution is vaporware, pipedreaming, frustration and I hate solutions like that where you have to be an insider technician.
sdowney717 is online now   Reply With Quote
Old 10-08-2019, 05:47   #9
Registered User
 
rgleason's Avatar

Join Date: Mar 2012
Location: Boston, MA
Boat: 1981 Bristol 32 Sloop
Posts: 13,302
Re: Add second GPS object to openCPN

Sdowney
Is this a complaint?
If we show you how, would you do it?
If no, perhaps you ask for the moon?
rgleason is offline   Reply With Quote
Old 10-08-2019, 06:50   #10
Registered User

Join Date: Apr 2010
Location: Newport News VA
Boat: Egg Harbor sedan cruiser 1970
Posts: 901
Re: Add second GPS object to openCPN

Quote:
Originally Posted by rgleason View Post
Sdowney
Is this a complaint?
If we show you how, would you do it?
If no, perhaps you ask for the moon?
Sure, show me how, here is an example GPS for you to do that as it can be configured many ways.
I bought this one to connect for the radio.
I would like to know all the commands needed to change things like baud rate, update frequencies from 1 to 10, select which satellite systems to use, output ttl or rs232, leave out certain statements, etc...they mention all of this they can configure.

https://www.aliexpress.com/item/3291...4de64c4dzX7ecZ

And 90% of all DSC capable radios that dont have a gps attached still dont as most people cant figure out even a couple of wires.

And before the reg changed, 90% of all DSC distress calls had no gps information.
They changed it to you can not make a DSC call without gps info, and now they want all radios to have gps integrated, except it has to be on a wire, cause otherwise, it may not have a view of the sky and still wont work.
sdowney717 is online now   Reply With Quote
Old 10-08-2019, 09:29   #11
Registered User

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,986
Re: Add second GPS object to openCPN

Quote:
Originally Posted by sdowney717 View Post


And 90% of all DSC capable radios that dont have a gps attached still dont as most people cant figure out even a couple of wires.

And before the reg changed, 90% of all DSC distress calls had no gps information.


They changed it to you can not make a DSC call without gps info, and now they want all radios to have gps integrated, except it has to be on a wire, cause otherwise, it may not have a view of the sky and still wont work.

1) most people can figure out, those who do not hire a technician,
2) clear sky is not required. sirf IV and newer chipsets do well down below.


Over many years I have only seen one vhf dsc unit that should, but did not have, the input. ymmv, I am in the EU / Spain / France, mostly.



I know it is not required (clear sky) as our neolithic today garmin is mounted below a sandwich (grp/foam) roof and gets lock in 15 seconds and never once dropped it.


SH makes vhf with gps chip inside. Hurry get one.


b.
barnakiel is offline   Reply With Quote
Old 10-08-2019, 09:40   #12
Registered User

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,986
Re: Add second GPS object to openCPN

OpenCPN should be VERY


REPEAT VERY


carefull in if and how it enables seconday gps tracking.


I agree: this can be a fine tool for few specific users (e.g. for me) BUT it can be downright dangerous for some other, less experienced users.


So imho a superb functionality just needs to be very very well thought out in software application.


b.
barnakiel is offline   Reply With Quote
Old 10-08-2019, 11:46   #13
Registered User

Join Date: Jul 2010
Location: Kalamata, Greece
Boat: Amel Sharki
Posts: 1,947
Re: Add second GPS object to openCPN

Up to now OpenCPN has no intuitiv function to add a GPS.
Imagine you have a car with navigation and have to install things like OpenCPN actually need to do. Imagine you buy a plotter for the boat and have to install things like OpenCPN actually need to do. Are there a lot of people doing this? Might be they ask the local vendor but nothing else.

So first do this better for OpenCPN before talking about connecting a second GPS. The average sailor is not a computer specialist.
CarCode is offline   Reply With Quote
Old 10-08-2019, 13:54   #14
Registered User

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,986
Re: Add second GPS object to openCPN

Quote:
Originally Posted by CarCode View Post
Up to now OpenCPN has no intuitiv function to add a GPS.
Imagine you have a car with navigation and have to install things like OpenCPN actually need to do. Imagine you buy a plotter for the boat and have to install things like OpenCPN actually need to do. Are there a lot of people doing this? Might be they ask the local vendor but nothing else.

So first do this better for OpenCPN before talking about connecting a second GPS. The average sailor is not a computer specialist.

I do not think OpenCPN is designed to be used inside car nav systems.


In any case, it had zero problem finding and using the gps on my tablet.


And I have never ever had a single class of IT.



Which leads me to the conclusion that car owners have become somewhat removed from the mean of human IQ. Like three sigmas or something.



barnakiel
barnakiel is offline   Reply With Quote
Old 11-08-2019, 06:49   #15
Marine Service Provider
 
bdbcat's Avatar

Join Date: Mar 2008
Posts: 5,632
Re: Add second GPS object to openCPN

barnakiel...


What is your concern about seconday gps tracking?


Dave
__________________

bdbcat is offline   Reply With Quote
Reply

Tags
enc, gps, opencpn

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Can I add a second Membrane to my Spectra Cape Horn Watermaker? yachtshah Plumbing Systems and Fixtures 73 02-03-2019 14:47
add a second radar screen? davil Marine Electronics 3 05-08-2018 03:57
How to add second head sail halyard to small boat Boulter Deck hardware: Rigging, Sails & Hoisting 5 02-06-2014 12:33
how to add a second steering wheel dancamp009 Navigation 0 06-04-2009 11:39



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 21:57.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.