Index: Force and Torque Measurement

When evaluating a new design, the stress analyst will usually measure not only the mechanical strains in the test structures, but the forces and torques that produce the strains as well. This is especially important when the objective is to determine the response of the design to known or anticipated loading conditions with an eye toward reducing weight and establishing safety margins. For measuring these non-strain loading parameters, the experienced analyst will generally opt to utilize commercially available transducers specifically designed for that purpose. But when the use of a ready-made transducer is impractical -- or even impossible -- strain gages can often be installed on some component of the test structure or loading fixture in a configuration that will enable the applied forces and torques to be measured directly. The physical arrangements and electrical circuits necessary for achieving these measurements are described below.

Configurations

Bending Loads
	Quarter Bridge Half Poisson Bridge Half Bridge Full Bridge
Axial Loads
	2 Gages In Opposite Arms Full Poisson Bridge
Torque
	Full Torsion Bridge

Fundamentals

Bridge Operations

Sample Calculation

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