Need help about accelerometers

[CanOzbek]

Hello, I am doing some research about human fall detection with accelerometers for a school project.

So far I learnt that, the data from x y z axises from a tri-axis accelerometer are combined in this equation:
value = sqrt(x^2 + y^2 + z^2)
and if this value exceeds 2.2g or 4g, it is concluded that a fall has occured.

My question is that can we use a one-axis accelerometer to detect human falls? Would it be sufficient ?

I appreciate your answers.

 

[barry]

A single-axis won't work unless your human falls right along the sensing axis of your accelerometer. As the acceleration moves farther off-axis, the output of the sensor drops off. If your acceleration is 90 degrees off-axis, the output is theoretically zero.