Accel calibrate needs orientation setting for Pixhawk2.1 as it is pitch180 by default

Ground Control Software APM Planner 2.0
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1

Pixhawk 2.1 arrived today and the first step of course was to hook it up to APM Planner and install the latest firmware, 3.4.2.

This I followed with an Accel calibration as it is always easier out of the copter.

To my surprise the HUD is now upside down. ???

Checked in QGroundControl and the HUD is still upside down.

Downloaded the latest daily build of APM Planner and redid the calibration, no change, the HUD is still upside down.

The solution I found in QGroundControl.
In the calibrate Accels QGroundControl offers the option of orientation with the default Pitch180.
If not changed this produces the same result as APM Planner.
Change orientation to None and recalibrate Accels.

HUD now displays correctly, and I assuming the orientation is now correct for the firmware

2

As you found out, the Pixhawk2.1 comes from factory with the orientation upside down as that is what is used by the test jig. If you are mounting it in the normal orientation you need to change the orientation back to None.

3

This is why I posted here in the APM Planner category, as APM Planner has no way to set the Accel orientation.

Fortunately I had installed QGC some time ago and managed to get through on that.

So I guess the title should have been different.
I will change it now.

4

You can always set the parameter in the Full Parameter view or reset the Params in the same view to default.

Still not a good experience for the PH2 to be configured incorrectly for first setup.

I’ll add a option to the accel screen.

Funnily I did ask @proficnc if there was anything in particular about the PH2 for setup and he said no. I wonder what other Params will need to be reset for safe first time setup?

I don’t have a board to test unfortunately

5

The parameter that causes the upside down HUD is AHRS_ORIENTATION. It was preset to 12 or 11 due to factory test program. Once it is set to a value of 0, for right side up, forward to be correct. Everything will be correct.

Another parameter to take care is BRD_TEMPERATURE, it should be set to 60 for the working temperature of IMU.

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6

Thanks for the reply, the AHRS_ORIENTATION one is obvious requirement to reset when you test the board. The BRD_TEMPERATURE one is most likely going to be missed by most users.

@muqing_cao @proficnc Do you guys know how we alleviate the board temp issue in particular.

7

Thanks for the heads up on the BRD_TEMPERATURE, I would not have known about that one.

What effect would it have set at 0 and not an actual temp value?

Just went looking for the parameter but it is not in the parameters list??
BRD_IMU_TARGTEMP is there and explains what it is about, and the default is 60
I assume it has been renamed.
I am curious as to why it is so high at 60deg/C?

8

setting the orientation to suite the setup is not unusual… it was setup like this on purpose to encourage users to follow the instructions and update the firmware…

then set the orientation as normal… most people need it set to 0

9

60 is the sweet spot for the mems sensors

10

Thanks @proficnc , I was wondering why it was heating up so much on the bench.

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11

@proficnc I set orientation as normal, 0, and now I get “BAD AHRS” displayed on HUD in mission planner. Am I missing something?

12

and you did a full calibration?

I really hate that message, as it has no information as to why it thinks its bad :slight_smile: