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Lab Room | Apparatus Map | Accelerometer | Calibration Principles

Calibration Principles

The accelerometer can be calibrated by applying a harmonic forcing function to the apparatus to determine the relationship between the forcing function and the output of the accelerometer.

For the accelerometer, the voltage output is proportional to the velocity and is given by:

(1)                                          

The accelerometer can be calibrated by comparing the voltage measured to the acceleration of the vibrating beam. The displacement versus time data that can be acquired with the strain gauges or the LVDT can be differentiated with respect to time twice to find the acceleration. The acceleration can then be compared with the voltage measured from the output of the accelerometer to find a calibration factor for the accelerometer.

Alternately the accelerometer can be calibrated by Static and Periodic methods.

Static Calibration: To perform a static calibration of the accelerometer, the device is subjected to a constant acceleration. The simplest method is to measure the output when the sensitive axis is upright, and again when the device has been reversed. Limitations of this 2-point calibration are clear, and include a limited range.

Another static calibration method involves a centrifuge. The resulting range is larger than the rollover method, but can be more expensive.

Periodic Calibration: A periodic calibration involves harmonic forcing of the accelerometer to determine the relationship between the forcing function and the output of the accelerometer. This may be done by rotation or with an apparatus like you will be using in the laboratory.


Last Updated: January 16, 2000, beam@bits.me.berkeley.edu
Copyright © 1993-1995, 2000, Pamela A. Eibeck and Brandon Muramatsu
Original WWW Conversion by Winston Wang, 1994
WWW ReConversion by Brandon Muramtasu, 2000