DVL A50 integration with GPS position

Blue Robotics Software BlueOS
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21

Thanks @EliotBR .

We’ve been using latest - greatest release rather than Master. So we can give testing with Master a shot.

We’ll give that a shot. We accept that there will be DVL outages and ideally we’d like to finish up at the surface and understand the deviation. So, it might look like a synch at the start and at the end.

We see minor jumps - like in the image I’ve shared in the thread above - and some major jumps. My gut says different causes but I don’t want to put a tonne of time into debugging if we’re moving away from EKF3 switching approach.

I’ll post an update after our next test.

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@PeterM I ended up going a slightly different route. I built a custom BlueOS extension that sets the initial position

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Thanks @ryan354 . Question for you: If you set GPS_TYPE to 14 (MAVLink) and use GPS_INPUT messages are you then having to explicity read off your GNSS? We have a simple M9N Ublox module linked into the Navigator serial port. Any chance of sharing a link to your repo?

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Hi @PeterM , sorry — I misspoke earlier, I’m not actually using GPS_INPUT. The extension uses SET_GPS_GLOBAL_ORIGIN to set the initial position.I also can’t share the repo on this one. But yes, I read the GPS data directly from the Navigator’s GPS serial port, process it inside the extension, then forward it back out to the other devices (DVL, INS, etc.) in whatever format they need (NMEA, etc.).

The extension set the DVL starting point, I’m currently running a Cerulean DVL — their writeup covers the same approach: https://docs.ceruleansonar.com/c/tracker-650/using-mavlink-and-blueos-for-position-hold-on-a-bluerov2/global-origin

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Thanks for the additional info @ryan354 !