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iNavFlight / inav

INAV: Navigation-enabled flight control software
https://inavflight.github.io
GNU General Public License v3.0
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IMU - Accel and Gyro temperature compensation #73

Closed digitalentity closed 1 year ago

digitalentity commented 8 years ago

I've been testing CC3D outside today and noticed that estimated attitude drifted a lot after I move the board from the room (+20 deg) to the outside (-25 deg). And by a lot I mean almost 70 degrees.

imu_dcm_ki was doing great job canceling gyro temperature bias, but the problem was accelerometer itself. It was also offset by low temperature and that was confusing the IMU.

We need a way to compensate for this temperature drift.

MauroMombelli commented 8 years ago

this is a know issue of the sensors, many say to be already taking care of it. (temp. compensated) Fixing that is quite hard has you have to create the specific drift curve based on temperature, and from here fix the reading; this require some sort of temperature controlled chamber witch provide at least 3 different temperature point to recreate the curve; also you'll need some sort of feedback from the temperature from the board, better if come directly from the sensor (another great issue is while the sensor is changing temperature, because it does not happen instantaneously).

hope someone can tell me wrong

2016-01-18 14:18 GMT+01:00 Konstantin Sharlaimov notifications@github.com:

I've been testing CC3D outside today and noticed that estimated attitude drifted a lot after I move the board from the room (+20 deg) to the outside (-25 deg). And by a lot I mean almost 70 degrees.

_imu_dcmki was doing great job canceling gyro temperature bias, but the problem was accelerometer itself. It was also offset by low temperature and that was confusing the IMU.

We need a way to compensate for this temperature drift.

— Reply to this email directly or view it on GitHub https://github.com/iNavFlight/inav/issues/73.

digitalentity commented 8 years ago

Today's test: From +20 to -25 deg. Gyro offset drift: (-2; 4; -2) degrees per second Acc offset drift: (0.05; 0.03; 0.1) G

Enough to cause attitude drift for 1-2 degrees, makes acro flying impossible as gyro bias is causing uncontrolled rotation.

brat002 commented 8 years ago

You can get Taulabs temperature compensation code for these needs.

stale[bot] commented 6 years ago

This issue / pull request has been automatically marked as stale because it has not had any activity in 60 days. The resources of the INAV team are limited, and so we are asking for your help. This issue / pull request will be closed if no further activity occurs within two weeks.

cptX commented 2 weeks ago

I have a 3" multicopter where the heat from the VTX causes drift of the MPU6000 up to 10 degrees! Turning the VTX Off the accelerometer comes back to 0 so I see a clear correlation between temperature and drifting... In fact by blowing directly on the MPU6000 I can see instant significant changes! I believe we should implement thermal compensation.