How to calibrate the accelerometer (LSM9DS1) of the Nano 33 BLE sense?

Official Hardware Nano Family Nano 33 BLE Sense
1

I have 2 boards of nano 33 ble sense.

and I tried to get the accelerometer data, I found that the z data of the accelerometer is not close to zero, it is close to 1mg.

but x y data is close to zero, each of my 2 boards is the same.

I think I can offset the z data to calibrate but I found another serious problem.
the range of the z data can not be offset also.

I mean that when the board is static the z data value is 1, but the detection range is -4~4,
so the detectable range always becomes 3 in the positive direction and 5 in the negative direction.
( please find the plot attached to this message.)

My question is how to calibrate the z data to zero and keep the detectable range at the same time?

2020-05-20_160802.png
2020-05-20_160802.png1162×850 67.8 KB

2

Your board is working fine. Below you is a big chuck of rock called earth. It accelerates your sensor with 9.81 m/s^2 or 1g. Lucky you, otherwise you might float into space. :slight_smile:

If you rotate your board you will see the +-1g in x or y direction.

3

ah, that makes sense, and now i see, appreciate for your kindly answer

4

I wrote an update for the LSM9DS1 library that incorporates calibration on all 9 DOF.

In the notes and manual.txt file there is quite an extensive explanation how to calibrate.
Unlike the other DOF, the accelerometer was quite accurate already.

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