IMU and Compass Calibration-How Often?

[rmb]

I have been in a few forums where I spoke about recalibrating the IMU after a firmware upgrade as I was told to do by someone at DJI. I was told by virtually everyone in the Mavic forum that that was terrible advice and that I should never recalibrate unless the app tells me too. I also mentioned that I was told to do a compass recalibration if I traveled more that 10 miles from where it was last calibrated and I was told by the forum that that was bad advice as well.

No, I was again in the Mavic forum so perhaps it is different with mavic, phantoms and inspires. Oh my

So perhaps we could get a pile of true or falses to the following.

Inspire 2
Always calibrate after firmware - true or false?
Always calibrate compass after traveling far from last calibration point -true or false?

And if you know, please him in
Phantom 4 series
Always calibrate after firmware - true or false?
Always calibrate compass after traveling far from last calibration point -true or false?

Mavic
Always calibrate after firmware - true or false?
Always calibrate compass after traveling far from last calibration point -true or false?

 

[JoePGM]

Hey rmb, regarding the necessary of calibration, I think it depends on manufacturer. I come from Yuneec TyphoonH and now own an I2.

If you look at Yuneec forum, there are lots of thread suggesting calibrate your Yuneec drone while travel to different location even short distant. I do that as well everytime and all flight are smooth and accurate.

On the other side, I could see DJI forum and official forum don't suggest compass and IMU calibration until you get system warning.

For myself, I still believe calibrating compass will give accurate data and so I will do the calibration on my I2 but only if I travel far away, so not as frequent as my TyphoonH. And also, only calibrate on the field with all smartphone turn off and keyring/metal objects away from the I2.

Hope this help.

 

[NickU]

Simples... check the values before you fly. Should be part of your pre-flight checks along with battery and RTH values.

If the mod values for the Gyro and Accelerometer (aka the IMU) are showing large variations deep into the yellow or red territory of the indicator bar, then consider recalibrating. If they're showing low deviations, ie they're barely showing in the green or are in the green and occasionally into the yellow areas of the bar, then you should be good to go. To fnd the values, head into the Quad settings (... top right of flight screen), and check the advanced settings - sensors. you should see the values for the Accel/Gyro and another tab for the compass values.

Same goes for the compass. You're better off getting a single good compass calibration and leaving it alone until it starts showing you there's a problem rather than calibrating it at every new site you visit. Even when it tells you there's a problem, treat the compass with caution as you could be sat over a load of iron - better to move to some clear ground 20-40ft away and check the values again before deciding if you need to recalibrate it.

IMU on the I2, I've only recalibrated it once since it arrived in January. Compass... again, probably only once that I can recall. One caveat though... I don't move a great distance east-west, probably only around 80-100 miles difference between locations.

Firmware updates - check the values afterwards and if they look OK, do a test flight in an area you know you can fly without problems occuring. If it flies OK, then you should be good to go. DO check all your flight parameters in DJI Go after both firmware and DJI Go updates, and DO do some test flights too.

Same applies to my Phantom 4.

 

[rmb]

Hey rmb, regarding the necessary of calibration, I think it depends on manufacturer. I come from Yuneec TyphoonH and now own an I2.

If you look at Yuneec forum, there are lots of thread suggesting calibrate your Yuneec drone while travel to different location even short distant. I do that as well everytime and all flight are smooth and accurate.

On the other side, I could see DJI forum and official forum don't suggest compass and IMU calibration until you get system warning.

For myself, I still believe calibrating compass will give accurate data and so I will do the calibration on my I2 but only if I travel far away, so not as frequent as my TyphoonH. And also, only calibrate on the field with all smartphone turn off and keyring/metal objects away from the I2.

Hope this help.

Really helpful. In fact anytime experienced pilots get involved in these discussions it is a fantastic learning opportunity. I think from now on it will be only the occasional compass recalibration when I travel and a cautious one at that.

 

[rmb]

If there was only one downside to this new found knowledge (of not recalibrating the IMU after each firmware update) it is that I was patting myself on the back that it was that level of fanaticism that was keeping me out of the "Firmware Flyaway" threads. So a) I was flirting with in constantly by doing it too often, and b) worse yet I guess the only reason that I have not had a flyaway in 4 years, six copters and countless flight hours is luck? ;0. Anyway I think this thread should be monitory reading for all pilots as I know so many doing it wrong.

Thanks to everyone for all of the valuable input.
Fly safe! rmb