How to remove Gravity factor from Accelerometer readings in Android 3-axis accelerometer

Question

Can anyone help on removing the g factor from accelerometer readings?

I am using SensorEventListener with onSensorChanged() method for getting Sensor.TY

Answer 1

Differentiating with respect to time a function of time rids you of the constants.

So by taking the derivative of the accelerometer's signal you'll get the "Jerk", which you can then re-integrate in order to get the non-constant part of the acceleration you're looking for.

In Layman's terms, take a sample from the accelerometer every 1 second, and subtract it from the previous sample. If the answer is (very close to) zero, you're not accelerating relatively to earth. If the result is non-zero, integrate it (in this case, multiply by one second), you have your acceleration.

Two things, though : -Look out for noise in the signal, round off your input. -Don't expect hyper-accurate results from on-chip accelerometers. You can use them to detect shaking, changes in orientation, but not really for knowing how many G's you're experiencing while making sharp turns in your car.