Hello,
i purchased a Razor IMU M0 from Sparkfun, which is based on the MPU9250.
In the product specifications from Sparkfun, it is written that the DMP sample rate is between 4 & 200 Hz.
I retrieve the pitch angle, computed from the "low power quaternions" computed directly by the MPU9250.
When the sample rate is configured at 100 Hz, eveything works well.
However, if the sample rate is increased at 150 Hz, some abnormal pitch values appear, even if the IMU is standstill
I put here two samples of data "accely, accelz, pitch" recorded at 150 Hz while the IMU was not moving at all.
Curioulsy, the acceleration and pitch are well continuous, except at the two samples where the pitch is abnormally large :
accely, accelz, pitch
-0,07 -1,00 -4,32
-0,08 -1,00 -4,32
-0,08 -1,00 -4,32
-0,08 -1,00 -4,33
-0,07 -1,01 -4,33
-0,07 -1,00 -4,32
-0,07 -1,00 -4,32
-0,07 -1,01 -4,32
-0,08 -1,01 -4,32
-0,99 0,02 -73,71
-0,07 -0,99 -4,32
-0,08 -1,02 -4,32
-0,07 -1,00 -4,32
-0,08 -1,00 -4,32
-0,08 -1,01 -4,32
-0,07 -1,00 -4,32
-0,08 -1,01 -4,32
-0,07 -1,00 -4,32
-0,07 -1,01 -4,32
-0,07 -1,00 -4,32
accely, accelz, pitch
-0,08 -1,01 -4,33
-0,08 -1,00 -4,33
-0,07 -0,99 -4,33
-0,08 -1,00 -4,33
-0,07 -0,99 -4,33
-0,08 -1,00 -4,32
-0,07 -0,98 -4,32
-0,07 -1,00 -4,32
-0,08 -1,00 -4,32
-0,08 -0,99 -4,32
-0,08 -1,00 -4,32
-1,33 0,02 -70,46
-0,07 -1,02 -4,32
-0,07 -0,99 -4,32
-0,08 -0,99 -4,32
-0,08 -1,00 -4,32
-0,08 -1,01 -4,32
-0,08 -1,01 -4,32
-0,07 -1,01 -4,32
-0,08 -1,00 -4,32
-0,07 -1,02 -4,32
-0,07 -0,99 -4,32
Since the quaternions are computed directly in the MPU9250, i think that the root cause for the erroneous value is in the MPU9250.
What is the maximum sampling rate recommended by Invensense for the quaternions computed in the MPU9250 and is 150 Hz allowed ? I did not find this information in the documentation.
Do you have any idea how to solve this issue of peak values ?
I would really appreciate very much your help!
Kind regards.