I am working on a human fall detection system using accelerometer and gyroscope which raises alarm in case of a fall. In all the papers I have read people have used net acceleration magnitude and compared it with a threshold and coupled it with change in orientation to detect fall. My question is would it be better to use acceleration in z-axis(normal to earth's surface) and compare it to threshold as compared to net acceleration as it might reduce false positives as net acceleration can exceed threshold in case of running but that won't happen if i take only acceleration in z-axis. Is my approach right?
Find the derivative of acceleration over time, also known as jerk. Falling will have a specific jerk pattern, whereas normal shaking and banging will have a completely differrent pattern.