6 axis IMU - Complementary filter

[matb]

Hi everyone,
I had time to work on my 6 axis IMU project and I'm having a couple of problems...

I have watched Phils Lab videos a couple of timehttps://www.youtube.com/watch?v=BUW2OdAtzBw&ab_channel=Phil%E2%80%99sLab I also have the BMI088 accelerometer & gyroscope.

I have a project that goes and read accelerometer data every 100ms. I verified on my scope that I have the correct frequency by toggling a pin.
 Capture.JPG (119.6 kB. 1299x988 - viewed 11 times.) tek00001.png (109.81 kB. 1920x1080 - viewed 6 times.)

So I have a 10Hz signal. I think ?

Code: [Select]

while (1)
    {
        BSP_PICs_Watchdog_Management(); /* Watchdog */

       
        if(Process_elapsed_ulong_time(u32_time, ul_internal_timer_never_reset_that) > 1000) // every 100ms
        {
            u32_time = ul_internal_timer_never_reset_that; // 0.1ms interrupt
            TP4_LAT = ~TP4_LAT;
            Accelerometer_X_Axis_BMI = Read_X_Axis_Accelero_BMI088();
            Accelerometer_Y_Axis_BMI = Read_Y_Axis_Accelero_BMI088();
            Accelerometer_Z_Axis_BMI = Read_Z_Axis_Accelero_BMI088();
            Gyroscope_X_Axis_BMI = Read_X_Axis_Gyro_BMI088();
            Gyroscope_Y_Axis_BMI = Read_Y_Axis_Gyro_BMI088();
            Gyroscope_Z_Axis_BMI = Read_Z_Axis_Gyro_BMI088();
        }
}

That code gives me a fixed sample rate of 100ms.

I record values in an excel file.

Then I go to Matlab (actually Octave) to compute my results using https://github.com/jshoga/IMU-Processing from
He doesn't give the units of the file but from my guesses accelerometer datas are in m/s² and gyroscopic datas are in rad/s.

I have a 0° → 45°→ 0°→-45°→0° record.
All I get are strange results am I missing something here ? Could someone try that I'm very confused by these results ?


Attached are the exemple files I am working on with my record of datas.

 accel3d_matlab.zip (1135.25 kB - downloaded 10 times.)