Microstrain sensor

Fig. 7.19. Reproducibility investigations of an EFPI microstrain sensor embedded in wax dnring cyclic heating and cooling [68]...

The dimensional changes measured by the strain gauge are typically very small, on the order of perhaps 10-100 millionths of an inch per inch (microstrain), but measurable physical deflections nonetheless. As the tooling deflects when a part is formed, the in-die force sensor which has the strain gauges attached also deflects, typically in compression. When this occurs, a resistance change takes... 

Insensys has developed a small, lightweight strain measurement system which can be used for aerospace, civil structures, marine, oil and gas industry, wind energy and research applications, enabling up to one hundred sensors to be multiplexed on one optical cable. Sensors can be bonded on the surface or embedded during composite lay-up with a sensor range of 6000 microstrain. 

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