Force imu 6050 to start yaw =0 in a physical plane position after calibration process

[MaxESP]

Hello all, I am building a tilt compensate compass with LSM303DLHC and imu 6050 .

All is good during the calibration process I have manage to store the offset before the interrupt and my compass is working well with dmp sketch.

my problem after the calibration on a flat surface is that i want that yaw start at 0 on a physical position of the couple LSM303DLHC and imu 6050 .

I am lost is it possible to achieve this .

[MaxESP]

Sorry I was wrong it's work now as expected

[MaxESP]

But the problem is that yaw drift a lot compare to roll and pitch why ?

[Aarpp]

hello did you mean you wanted yaw to always be zero on initial startup ?
I managed to always have yaw as 0 using a compass with tilt-comp on a UAV i made by creating a vector that stores the last input desired yaw value and storing it. happy to share IF that is what you are looking for.
I also used sensor fusion or a simple comp filter to combine ypr[0] and tilt heading, resulting in a steady non drift yaw value.

I apologize for not better understanding your question.

[Halvhjearne]

i would like to see example of this, if you dont mind?

[MaxESP]

hello Halvh,

You have to declare all the data variable at global variable to 0 and the couple mpu6050 and LSM303DLH_ on a flat surface to make the calibaration
float roll =0;
float pitch=0;
float yaw=0;
float angle_yaw=0;

int deg1 = (headingDegrees1);
int angle_yaw=yaw;
//angle_yaw -= course_deviation(angle_yaw, deg1) / 1200.0; //Calculate the difference between the gyro and compass heading and make a small correction.
if (angle_yaw < 0) angle_yaw += 360; //If the compass heading becomes smaller then 0, 360 is added to keep it in the 0 till 360 degrees range.
else if (angle_yaw >= 360) angle_yaw -= 360;

//Serial2.printf("%i,%i\r\n",deg1,roll1);
Serial.printf("%i,%i,%i\r\n",deg1,roll1,angle_yaw);
Serial.println("");

[MaxESP]