New "function" suggestion

1

Background:

Normal phone compass can many times be very unstable, and show wrong. And Heading with “Normal GPS” is only valid as long as you are moving.

My suggestion:

Can it be possible for KrakenSdr to use one input on RSPi5 to connect a GPS/GNSS compass. This type of compass for example Furuno deliver either NMEA or NMEA2000. But best for KrakenSdr is normal NMEA0183. And the only thing KrakenSdr needs to listen to is the HDT (True heading from north).

Now days its very cheap also to buy a GPS(RTK) compass online.

We are using here on all our pilot ships FURUNO GPS/GNSS compass. And instead of a big heavy gyro, gps compass is good and give a steady heading.

To be able to connect a GPS compass makes it easier to use a mobile direction finder, even when standing still.

1 Like
2

It’s possible but so far I haven’t found a proper library that can support external compasses. It seems that to support external compasses we would need to support each one individually which is not feasible.

I believe there are some compass devices already supported by GPSD which is the library software we use for external GPS devices on the Pi. But so far I haven’t been able to determine exactly what compass devices are compatible as there doesn’t seem to be a list that tells me what supported compass devices there are.

3

You don’t need to focus on specific GPS/GNSS compasses, instead focus on the NMEA 0183 protocol, This protocol is international and the same for all equipment.
For those who don’t know what it is there is information here.

And there is only one NMEA that is interesting, and that is the heading.
I was actually on one pilot ship yesterday and working on a GPS/GNSS compass, and needed to remove a lot of NMEA that the track pilot didn’t need.

So krakenSdr only need to listen, and sort out the heading, and scrap the rest that compass is sending. Standard is 4800,8,1.

4

Do you have a recommendation for a reasonably priced GPS(RTK) compass that we could use for testing?

5

Hi,
Commercial like Furuno, simrad etc is only found on surplus market for a private person, but cheap New, can for example be found at below link, Same or almost same can also be found on for example Aliexpress.
As you can see, almost all equipment use NMEA 0183, and that is very common protocol.

And on Aliexpress for example this.

6

Thanks, and I assume these also provide a GPS position as well as the heading?

7

Yes they do, and its better then a mobile phone.