Compass calibration? Does "Live Calibration" work for Rover

Trying to sort out compass calibration issues here

One other problem seems to be that “Live Calibration” doesn’t get ANY samples. I’m rotating the rover around all the axes, and getting nothing.

@mroberts,
Does your Pixhawk and GPS/Compass orientations have to absolutely be the way that you have mounted them? I would try and start out with the standard configuration of both the Pixhawk and GPS/Compass oriented to the front of the rover and make sure that works before trying different orientations.

I have recently calibrated a GPS/Compass module with my Pixhawk and I have the standard orientation with the Pixhawk and GPS/Compass module facing forward on the centerline of my rover.

You can use the CLI to see what compass is being used by the Pixhawk when it starts up. If the outboard compass is being used it will indicate that when starting up in the CLI.
Regards,
TCIII ArduRover2 Developer

Tom,
Running the CLI, I get:

[code]Setup: compass
Compass:??

enabled
Mag declination: 0.0
Mag offsets: nan nan nan[/code]

Running the “live calibration” in the GUI, whether connected vai USB or radio it doesn’t register any samples.

@mroberts,
Sounds like a bad compass based on the CLI indications of compass health.
I suggest that you contact the vendor from whom you bought the compass.
Is it a 3DR compass or a 3rd party component?
Regards,
TCIII GM

Tom,
It’s the 3DR GPS/compass module.

Does the “enabled” mean the on-board or off-board compass is being used? The way it’s currently running, it seems to be forcing COMPASS_EXTERNAL to 1, so looks like its seeing it. The heading does change in the correct direction as I turn the board (I’ve got the PX4, compass and radios all mounted on a board I can yank for testing), but it never seems like the heading matches reality.

Is that an indication of a failed compass module, or a PEBKAC somewhere in the setup / calibration process?

Should I “reset” the compass via the CLI?

If I pull the compass and just run on the internal one, should I be able to calibrate successfully, and should it show as “enabled” or “disabled” in the CLI?

Downloaded 2.45 - seems to work now.

Getting 0.0 declination, but setup for “auto declination” and not getting GPS, so I assume that’s driving the zero.

No longer have nan for offset: -144, 39.2129, 257.7244

They seem higher than desired, but could be due to the honking great steel beam behind the desk. Getting a value is certainly a step up!!

Once this is installed, it wont be possible to actually rotate the rover in all axes - it will be a bit heavy. Can you calibrate by driving in circles or a figure 8?

@mroberts,
Fortunately for me my rovers are much smaller, around 1/10 to 1/8 scale, so it is easy for me to do the live calibration.

I do not think that driving in circles or in figure eights will provide you with an accurate calibration. I go through all the axes including upside down and usually am able to get offsets that are around 70 to 80.

This is one of the reasons that I prefer Traxxas molded chassis over aluminum or steel chassis:-)
Regards,
TCIII ArduRover2 Developer

My 3DR GPS/compass does not work either with APM 2.6
I can read GPS info when testing by terminal
But for compass I have the message
"compass disabled"
When I try to put compass on whit setup, it gives the message
"Compass initialisation failed"

It seems to have a lot of configuration or quality problems with this compass !
It should be plug and play but is not.

Edit: I tested the 3.3V regulator: 0V output !
APM back to seller.