During almost 80 years of service, strain gages have proven to be remarkably accurate and reliable mechanical load sensors. They now dominate weighing including static, dynamic, precision and legal for sale applications. They are also used in the vast majority of precision torque sensors. All Himmelstein torque sensors are strain gage based. The simplest torque sensor is depicted in figure 1 below. When torqued, the element is stressed in shear – on a plane through the shaft, perpendicular to the shaft axis. The shear stress creates equal magnitude tensile and compressive stresses at 45 degrees to the shaft axis. Strain gages are installed at 45 degrees to the shaft axis and sense those tensile and compressive stresses.
