QTVLM and Raymarine Autopilot

Good morning!
After several years with Opencpn, I’m switching to QTVLM. It works very but I have a problem: I cannot send the navigation information to Raymarine autopilot in order to use it in track mode. I see all the information of next waypoint, but when I push truck the Autopilot says “no route information”. Checking the NMEA log, it seems that there is no APB and XTE sentences.

Could you help me to solve the matter? Any experience?

Many thanks and best regards.
Giulio Canale

Hi,
As I said on Facebook to your same question, I don't know why it does not work, and I don't think it is due to XTE or APB messages which are something else, Here is what Raymarine says for a similar question:

Please note that Track mode may only be commanded after having satisfied the following conditions:
- the system has acquired a GPS position FIX
- the system's chartplotting device has been commanded to navigate to a waypoint/cursor position or to follow a route ... doing so would then trigger the system's chartplotting device to transmit the associated navigation data to the SeaTalkng / NMEA 2000 backbone permitting the autopilot to then be commanded into Track mode.

So one question is: you said the pilot sees the WP qtVlm has sent, but does it also has a GPS fix ?
Have you tried checking "With NMEA 2000 compatible names" .?

Thank you for the information.
In my boat QTVLM is connected with YDWG-02 Wifi. I’m also in contact with the support of YDWG and I share their information.

- They confirm that APB and XTE sentences have to be transmit by QTVLM in order to share the navigation information with AP and use track mode. In the same way I confirm Opencpn is transmitting the 2 sentences and the track works regularly.
-I confirm the system has acquired GPS position FIX. Here the log:
SRV[0] TX:
$YDGLL,4526.2098,N,01331.2145,E,124202.00,A,A*60
$YDRMC,124202.00,A,4526.2098,N,01331.2145,E,0.2,276.7,020524,4.4,E,A,C*54

Is possible include APB and XTE in next release? For me it’s very important to have track mode, If not I’m obliged to come back to Opencpn.

Many thanks and best regards.
Giulio

I don't understand why APB and XTE would be necessary in track mode. RMB message sends the coordinates of the active WP and if the system knows the position and the magnetic deviation than should be enough.
Again quote from Raymarine support, from this page:  forum.raymarine.com/showthread.php?tid=4077

The RMB NMEA 0183 sentence contains BTW, DTW, WPID and XTE all in one sentence. As such, the autopilot will support tracking when this single NMEA 0183 sentence is received, as long as the included bearings are Magnetic as indicated above.

The problem seems to be that qtVlm is sending bearing as True in RMB message, since there is no way to send Magnetic bearings in a RMB message.

On some models it is possible to enter/force a magnetic variation, do you have that possibility ?

Hi, I am waiting for your answer concerning forcing manually variation before implementing anything new
--Philippe

Dear Philippe,

I have done several test today, but without success. I have also tested TZ iBoat that I'm using on my ipad. In one of the last update they permit to config the nmea output for the autopilot: in particular you can choose which sentences "export" and the options include also APB and XTE. I tested it and it works fine: the raymarine autopilot can work in truck mode.

I have also share your doubts with yacht devices support, and I'm waiting their reply. I think that APB is mandatory to use Raymarine AP in track.

Please let me know if you can add it in your next release.

Many thanks and best regards.
Giulio