The development of a low Z strain transducer

Prototype, low Z strain transducers of three different designs were developed for measurement of strains to 4,000 microstrain laboratory impact testing of rings, frustra and other structural shapes. These transducers use beryllium foil electric resistance strain gages as the sensing elements which are wired in a half- or full-bridge arrangement to eliminate bending in the transducer and provide temperature compensation. The beryllium gages can withstand a maximum of 1,200 microstrain, due to the limited ductility of the beryllium foil. The transducers were designed to attenuate the strain and permit measurements to 4,000 microstrain, without subjecting the sensors to more than 1,200 microstrain. Attachment to the test article was by means of resistance spot-welding or electron-beam welding.