Roll Pitch and Headings about adafruit_bno055 HOT 4 CLOSED

the absolute orientation may need to be rotated based on your usage. also you should use quaternions not euler to avoid errors at 90/180/270

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I rotated the axis which is the correct way to do it according to the datasheet. If you leave the axes as are and then apply rotations to the orientation then you won't get the right answers because the fusion algorithm uses magnetometer differently depending on the tilt with respect to its z axis.

I thought the answer may be due to using Android orientation, but that doesn't really make sense.

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@DrJaymz In my case, roll is around -Z, pitch is around -Y and yaw is around -X. So roll and yaw are switched and have the reversed sign. Pitch is correct but its sign is incorrect.
In other words, the library's default config does not match with the datasheet's default axis.

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I think there is a bug in that for euler angles the z rotation is read from the sensor and put into the x part of the output vector. And the x rotation from the sensor gets put into the z part of the vector. There is also some weirdness with signs, but i didn't look into that.

I think this is because the library reads from the registers in this order here, which is heading, roll, pitch. It then writes heading to X, roll to Y, and pitch to Z here.

I've seen conflicting info out there on whether pitch corresponds to x rotation, or pitch corresponds to y rotation. I've tested with this sensor and this breakout board and the data in pitch register corresponds to X rotation in default axis mapping.

  BNO055_EULER_H_LSB_ADDR = 0X1A,
  BNO055_EULER_H_MSB_ADDR = 0X1B,
  BNO055_EULER_R_LSB_ADDR = 0X1C,
  BNO055_EULER_R_MSB_ADDR = 0X1D,
  BNO055_EULER_P_LSB_ADDR = 0X1E,
  BNO055_EULER_P_MSB_ADDR = 0X1F,

  readLen((adafruit_bno055_reg_t)vector_type, buffer, 6);

  x = ((int16_t)buffer[0]) | (((int16_t)buffer[1]) << 8);
  y = ((int16_t)buffer[2]) | (((int16_t)buffer[3]) << 8);
  z = ((int16_t)buffer[4]) | (((int16_t)buffer[5]) << 8);

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