Single axis PCB piezoelectric accelerometer with usb daq to get position possible?

[kawarko1]

Can I get live position only one axis say z with USB Daq (48 khz sampling rate) on Lab view. I have a single axis PCB accelerometer with good sensitivity.

[dsb@NI]

To convert acceleration to displacement, integrate twice with respect to time.

Integration of acceleration generally doesn't work for IEPE accelerometers mounted on DUTs that are actually moving their center of mass because errors (especially DC measurement error) accumulate in the displacement result.

Integration works great for

 - Vibrations around equilibrium - to avoid integrating DC error over time, use an AC Coupling (high-pass) filter before and after integration.

 - Short duration tests such as impacts - you can decide exactly how to process the data (i.e. integrate DC vs remove DC, apply known initial and final conditions, etc.)

I would use an IEPE accelerometer on an engine to measure engine vibration, but I would not even try integrating (twice) to try and see how far down the road the car had moved.

Generally, measure the phenomenon you want - in this case displacement.

[Henrik_Volkers]

The IEPE accelerometer and the signal conditioner (USB DAQ with IEPE supply I assume) each  already have a highpass filter included (but also have an offset) See Specs . The double integration also should add a highpass (but you can choose a lower frequency)

If you have the sensor mounted on something and that something don't leave the room  (and your sensor isn't changing orientation in earth gravity) movements faster than the filter constants should result in coarse results.

If you have a sine movement with known frequency f you can do a scaling with -(2*Pi*f)^2   😄