# Calculating mV/g of a sensor

I have constructed a piezo-resistive sensor using graphite. I managed to obtain the output voltage of 0-5V by using the ADC of my Arduino to read the sensor. But I have no idea how to calculate its sensitivity. Any suggestions?

Some things on this post were similar to my question: Calculate G's of an Accelerometer

But I need to know how to calculate the mV/g instead of getting it from the datasheet.

• Have you tried putting it on a fixed, flat, level surface? – Ignacio Vazquez-Abrams Sep 30 '14 at 20:10

Trying to measure the offset by pointing the accelerometer horizontally is a lot more difficult because it's a sin($\theta$) function rather than a cos($\theta$) function so a relatively small angular error results in a relatively large error in g. For the same reason, small errors in angle don't matter so much when measuring the sensitivity with the accelerometer close to vertical in either direction.