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Single Arm Active Bridges
Single Arm Active Bridges
A single active arm bridge has one strain gauge, pictured above in position R1, on the Wheatstone bridge. Assuming a voltage-sensitive deflection bridge with all resistances nominally equal, a zero initial output voltage, and small resistance fluctuations, it can be shown that the output voltage will be given by:
(1)
where:
- eo is the bridge output voltage,
- ei is the bridge excitation voltage,
- R1 is the change in resistance of Resistor 1, and
- R is the nominal resistance.
It can also be shown that the strain can be related to the ratio of output voltage to excitation voltage by:
(2)
where:
-
is the strain to be measured and
- F is the gauge factor.
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