Defective IMU

Hello everyone,

I tried to do a thermal calibration on my cubes and detected issue with 2 of them.

On the first one, the accel 2 sensor don’t start if I power the cube at a temperature is below about 30 °C. Above, it is fine. Here is a log: https://review.px4.io/plot_app?log=96f10869-bf2c-463b-b39a-1d757a403afe

This is repeatable on this cube.
Is it a known issue? Does it happen frequently?

On a second cube, I noticed a strange behavior on gyro 2: The bias is really not stable. It can change very quickly. On the figure below, we can see a quick change above 40°C and at about 73°C we can see a step change. At 73°C, the same change can be seen on accel 2 but not on the other sensors. On gyro 2, it doesn’t look like a real move but a step on the bias.


The absolute bias variation is not so big but it is quite rapid. Can it be a problem? Will it be noticeable during flight?

Hello, When have you bought your cube? I need the date. not the exact one but the month will be fine even.

Hello,
We bought it at the beginning of July 2019.

These series are the ones which are only working correctly with the latest APM till now. With PX4 nothing that much good will happen.

Download the latest Copter or Plane with APM and see if the issue persists?

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Please contact your reseller for assistance in setting up an RMA

Yes, same issue with arducopter 4.0.0

Ok, I will do that. Thank you for the reply

What do you mean, same issue with Ardupilot?
What error message did you get on mission planner?

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I did not get any error message on mission planner but IMU2 acc are constant: accX = -235m/s/s accY = 235m/s/s and accz = -235m/s/s

Here is an arducopter log https://drive.google.com/open?id=1b6C9gl8S4luoJ0WjSbWo49JmuCv9-6y6

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