February 9, 2020
A strain gauge is a sensor whose resistance varies with applied force. To measure the variation in resistance, the strain gauge is placed in a bridge configuration. This design uses a 2 op amp instrumentation circuit to amplify a differential signal created by the change in resistance of a strain gauge. By varying R10, a small differential voltage is created at the output of the Wheatstone bridge which is fed to the 2 op amp instrumentation amplifier input.