Toilet bowl phenomenon during loiter flight

Good morning
This is a question related to the weird hexa from last time.

The toilet bowl is a very common problem, and it’s an easy one.

But the toilet bowl I experienced this time is not easy.

This is no problem in loiter flight at the time of no payload.

I mounted a long stick payload at the bottom.

This is 3 kg.

And this hexa does a toilet bowl.

There was no meaning in adjusting the values ​​such as

What’s the problem?

I am attaching my parameters and binary log.

Is there any way to change the parameter of px4 saved as a file to the parameter of apm?



Mag 1 is susceptible to interference (throttle). Mag 2 is not. Ground Mag Anomaly errors as a result.

No idea what you mean by this. APM is a piece of obsolete hardware. PX4 what? The Flight Stack?

Thank you for answer.

  1. Is this problem caused by “Ground Mag Anomaly errors”?

  2. In flight without payload, it flew without problems, with 3kg payload applied and toilet bowl phenomenon was observed.
    Why is this?

  3. This is a question about whether it is possible to upload the parameters of pixhawk4 FC to which px4 firmware is uploaded to Pixhawk4 FC where apm firmware is uploaded as it is.

Thank you

You are mixing up your terms a bit - I think you are asking if you can use parameters from the PX4 firmware in Arducopter firmware. Definitely NOT, the maths and many things are entirely different.

And what Dave is suggesting is you disable the internal compass and retest the flight, the problem might be gone then.

Thanks for the reply as always shawn.

I have a question here.

If internal compass was the problem, it should have happened before the payload was applied.

no payload = no problem

3kg payload = yes probelm

Additionally I found the “ATC_ANG_PIT_P/R/Y” parameter.
Given the P-value for the angle, can this solve the toilet bowl enough?

First, as your advice, let’s fly without using an internal compass.

Another question here.
I am not already using Compass 3.
If i also turn off the internal compass, it’ll end up flying only with Compass 2, is this okay?

Thanks a lot

Higher current demand with payload could explain this.
Actually Mag 1 is your external compass.
COMPASS_DEV_ID,658945 (This is on the I2C Bus)
COMPASS_DEV_ID2,658953 (This is on the SPI Bus-Internal)

And there is no “APM Firmware”. There is Ardupilot Firmware and PX4 firmware and they don’t mix.

I confirmed that there are two compasses in the compass calibration item.
So far, one spi and one have been listed as i2c, but these hexa are both i2c.
I’m new to pixhawk4 so I’m not sure, but is this normal? I haven’t touched any parameters. Additionally, during the test yesterday, I remembered your words and disabled compass1, and the ekf in the hud window was still stuck in red. Are compass and mag two different concepts?

That’s not what the parameters show for the log you posted.

No, same sensor 2 different words to describe them.