Quaternion accuracy

[Newguy]

What does the accuracy in quaternion.c represents? I notice that when it isn't 180, the value of quaternions becomes unreliable.

Additionally, I also see that the accuracy sometimes changes when there are sudden motions (like when I am rotating the sensor consistantly). Is there a way to fix or acconodate this?

[BSTRobin]

Hi Newguy,

Accuracy represents the calibration status of the virtual sensor.
You need to calibrate the accel, gyroscope, and magnetic sensors first, and then test the quaternion values to obtain more accurate outputs.

[Newguy]

Thank you for your response, I am sorry for the late reply.

Can you tell me how to calibrate the sensor? I am unfamiliar with this process

[Newguy]

Additionally, does linear acceleration have a dynamic offset? How can I remove that?

[BSTRobin]

Hi Newguy,

You can refer to the software code in the attachment and enable accel, gyro and mag for calibration. The calibration status can be obtained through the callback function. Usually, the sensor calibration is completed only when the calibration status reaches 3.

Calibration is not automatically completed by the sensor and needs to meet the following conditions:
Accel: 6 axes calibration.
Gyro: keep sensor stable.
Mag: hold the device in hand and draw an eight movement in the air.
The built-in BSX algorithm of BHI360 runs in the background, only requiring the device to meet the above calibration conditions. Please refer to this video for detailed calibration method: https://www.youtube.com/watch?v=Bw0WuAyGsnY

After the calibration status of accel, gyro, and mag reaches 3, use the algorithm output from BSX (such as quaternions, euler, etc.).