Gyroscope that doesn't need Calibration every reboot

Using Arduino Sensors
#1

Hello guys,

I lost my directions here (pun intended?)

Most of us know our smartphones don't need to be calibrated everytime we want to use the gyroscope (Although I found out some old Samsung devices could do this).

I've been experimenting with Gyro and Accelero to get the current angle of the sensor, but this only works after you calibrated the thrifting for a few seconds. Note that I need the angle, so It's more complicated than just getting the acceleration.

Why do I need to calibrate this each time I repower my sensor? How do phone companies for example manage to not make the user calibrate it?

I've been using the MPU6050 (or some of that serie) with Kalman filter, did I just use the wrong algorithms? Do manufacturers test the thrifting and save those values before they get shipped to customers?

Thanks a lot

#2

All rate gyros drift and the drift depends on the temperature. Some manufacturers hide the calibration step, by doing it when the gyro seems to be reporting "no rotation".

#3

These days phones use gyro/accel/magnetometer (ie 9DoF) sensors, and you need to calibrate the
magnetometer for best performance, but it will still drift-correct the gyro anyway.

#4

You don't have to do the calibration on every power-up. If you store a calibration once, then it will be good for a time. Eventually you will get drift and you have to recalibrate.

Most phones do have a recalibration. They probably also cheat by detecting no movement on the accelerometer and then use that to zero the gyro. Maybe when it's plugged in to the charger too.

#5

Interesting !

Thanks a lot guys, this helps much!

#6