Calibrate IMU?

JeffreyS

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What exactly is the IMU in my P4P and why would I need to calibrate it?
 

dirkclod

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An Inertial Measurement Unit (IMU) is an electronic device that uses accelerometers and gyroscopes to measure acceleration and rotation, which can be used to provide position data.
Googled that.😏
I always have done one when I have done a firmware update
just from habit.
If I’m having just any strange flying issues I will do one.
We used to do cold ones in the summer with the P2’s
to help start up quicker.
 

ianzone

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Imu
Screenshot_20200617-083311_Chrome.jpg
 

JeffreyS

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Did you get a message that indicates a problem or some form of odd characteristic in flight?

No message, but I still have yaw drift that make still photography difficult. I calibrated the controller sticks, but wanted to learn more. What a shame that these aircraft controllers do not have trim pots to fine tune the crafts ability to hover still. The drift is very unpleasant.
 
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I don’t believe you’ll be able to remove the drift via an imu calibration.
With what I see in the other DJI products that I have(tooooooo many)that all seem to do the same thing, I think we’re stuck. Imu calibration didn’t change any of that feature.
 

ianzone

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No message, but I still have yaw drift that make still photography difficult. I calibrated the controller sticks, but wanted to learn more. What a shame that these aircraft controllers do not have trim pots to fine tune the crafts ability to hover still. The drift is very unpleasant.
Props balanced ? You could try bit of tape on opposite side of yaw drift which will rule out unbalanced props or prop,,are all motors spinning same speed,,compass been done to eliminate it too,
 
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Drift is unlikely to be caused by the imu directly. Position stability is the job of the GPS system. It’s information gets integrated with the imu, altimiter, and user inputs to control the drone flight. This solution is being updated many times a second to fly or hover. The conditions are always changing - wind speed, wind direction, gps signals etc.

In your case, it sounds as if you may be experiencing some effects of the GPS system. The GPS system position information is also getting updated multiple times a second. It will never have exactly the same value twice, even if anchored to the ground. The GPS satellites are in constant motion, and their time clock signals have some jitter to them. The normal system is only specified to deliver accuracy within 16 feet 95% of the time. Generally it is quite a bit better. This effect can easily be demonstrated by performing a few RTH thru landing with the precision landing disabled. Most landings will be within 4 or 5 feet, but rarely better.

Exactly the same effect can be seen in a steady hover where the drone drifts randomly in a several foot radius. Drones used for serious mapping use more expensive, more accurate GPS Systems to avoid exactly this problem. Purchasing one of these solutions would solve this issue for you
 
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Oh, don't push him too hard. Buying a new drone? Must be another way. Yaw drift he was asking about is not an usual habit of Phantoms.
And I do not believe that I am so lucky that my P4p has no such drift.
Most likely the majority of Phantoms haven't.
It should be eliminated at an repair. I'm not a drone technology expert but at least DJI should know how..
It is really annoying issue.
 
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