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Measuring pitching and rolling angle in AltIMU-10 v5


I’m using AltIMU-10 v5. I finished calibration of LIS3MDL. Ans then, I think yawing angle is not problem.

When I rotate the sensor in pitching direction, the angles are increased in plus or minus directions. However, the angles are decreased after specific angles (about plus or minus 35 degree). In addition, if I stop the rotation at up to 35, the angles are continuously decreased or increased.

Is there a solution to fix it?

I use a arduono code which is provided from Pololu:
Pololu MinIMU-9 + Arduino AHRS (Attitude and Heading Reference System) version: 1.3.0.

Please let me know if there is any aolution.



I am sorry you are having trouble with our AHRS code. It might be that your sensor signs are not agreeing somewhere. Have you made sure you are using the appropriate values for the SENSOR_SIGN array in MinIMU9AHRS.ino based on the orientation of your board in your application?



Thank you very much.

I have two more questions.

  1. Now, the yaing angle takes few seconds to be stable. Is this normal operation?

  2. Angles in three directions are accuracy when Z axis of the module is the same with direction of gravity. However, angles in three directions are not accuracy when the Z axis of the module is perpendicular with direction of gravity.
    I think that this is because of SENSOR_SIGN array. Could you please let me know how can I determine the signs. I cannot understand what they mean. I use the array of {1,-1,-1,-1,1,1,1,-1,-1}. In this case, yawing angle has to be increased when the module is rotated in count clockwise. However, it is decreased.

Thanks again,

Have a nice day!!


That does not sound like normal operation. What is the orientation of your AltIMU-10 in your application?