[hakan.frojdh]

Is it possible to get support for nmea data over udp? Serial port would be better! We use gps compass and rtk and that needs to be input to your system, the http interface make this system much more troublesome to interface on our ship and work boat. All positiong, heading and mru data are serial and nmea 0183 or the same strings over udp.
/H

[wlkh]

Hi,

Sorry for the late reply.

Currently NMEA output is not supported. It is possible to generate NMEA similar to our example of inputting NMEA (https://github.com/waterlinked/examples/blob/master/externalNMEA.py) if you are comfortable with programming. (Here is an example of generating NMEA: https://gist.github.com/JoshuaGross/d39fd69b1c17926a44464cb25b0f9828)

We have been evaluating supporting NMEA so if you have additional information on what sentences should be generated that would be helpful. I would guess GPGGA or GPGLL.
Should the prefix “GP” be user configurable?

NMEA over UDP is easier for us to support than UART.

Best regards
Kristian
Water Linked

(PS. If you haven’t already, you should upgrade to release 1.4 for better performance: https://update.waterlinked.com/)

[wlkh]

To make it easier for you, I’ve created a Python script now which can be used to output NMEA from the Underwater GPS over UDP or Serial port on your computer.

It is available here:
https://github.com/waterlinked/examples#about-nmeaoutputpy

Hope this is helpful. (And yes, it will be much better if we can integrate it into the Underwater GPS in the future)

Best regards
Kristian
Water Linked

[wlkh]

I’ve now updated the scripts to support:
* Receiving GGA/HDT sentences from UDP or serial and send to Underwater GPS to use as reference system (nmeainput.py). Eg: using a high quality GPS/Heading source to improve position accuracy.
* Sending the underwater position / Locator position as GGA sentences over UDP or serial (nmeaoutput.py). Eg: using the Underwater GPS position in a chartplotter.

Best regards
Kristian
Water Linked

[koppel.bo]

This way might be a solution for my old idea of using AIS sentences for ROV positioning on bridge/helm position.
Sending position as AIS via UDP or serial to a ROV dedicated plotter or PC based system.

Why?
-Gives automatic distance and bearing to ROV
-Displays ROV on Nautical charts
-Easy working with Gpx waypoints and tracks
-Easier manouvering of ship related to ROV
​
Bo Koppel

[wlkh]

Hi Bo,

Correct, you should be able to push the position over UDP (easiest) or serial to a chart plotter with the scripts.

I would also recommend taking the reference GPS and heading from the boat and using them as “external reference” for the Underwater GPS.
They are typically very high accuracy and will give a better position than using the the onboard GPS and IMU on the Underwater GPS kit.
The external reference is configured in the “Global reference” section of the GUI (http://demo.waterlinked.com/#/settings)

Best regards,
Kristian
Water Linked

[koppel.bo]

Hi again!
I have still not received my system so this is probably a stupid question:
How do i connect and transfer my python files to the onboard API?
Bo

[Oliver Skisland]

Hi Bo,

You connect to the system with an ethernet cable which comes with the system. The python files runs on your computer which you connect to the system via the ethernet cable. The python scrips pulls data from the system using the software API.

Best regards,
Eirik
Water Linked

[koppel.bo]

HI!
Got NMEA out and in running!
That gave me one more idea:
Sending heading/orientation as well via NMEA.
Useful in plotters as well as in tracklog.
That should probably be done with RMC instead of GGA since GGA dont support heading.
Has anybody done Python programming for fetching orientation from Waterlinked and parse that to RMC Heading?
Bo

[wlkh]

In case someone stumbles in on this topic:

Bo has actually implemented an integration with the OpenCPN plotter. Thanks Bo!

More information here:
https://discuss.bluerobotics.com/t/rov-plotting-on-nautical-chart-and-ship-rov-on-same-chartplotting/3746

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