The present invention is in relation to strain gauge based on reduced graphene oxide nanosheets embedded on to cellulose material and integrated on to a stainless steel diaphragm. The invention is also in relation to transducer comprising the aforementioned sensor and method of fabrication thereof. The developed sensors (figure 4(a)) shows the sensitivity of about 1.19 Ω/ bar. The test results shows the combined effect of nonlinearity and hysteresis is 1.219% FSO (Full Scale Output). The gauge factor of RGO strain gauge based pressure transducer is found to be 124, which is high compared to conventional gauges. Figure 4(c) shows the strain distribution with respect to the applied pressure by simulation, standard strain gauge and RGO strain gauge experimental. Over the years many potential improvements in sensor performance are realized by using structures and sensing elements complementary to each other, like flat diaphragm, boss diaphragm, embossed diaphragm and cantilever beam structures to name a few. Structures and sensing materials have played a very important role in realizing non linearity, hysteresis, sensitivity, repeatability, and accuracy characteristics of these pressure sensors. Pressure sensor have a wide range of applications in the fields of automotive industry, aviation, touch screen devices, medical field and the like.
Figure 4: (a) 3D drawing of the complete assembly of the pressure transducer assembly and inset shows the fabricated assembly of sensor, (b) Input –output characteristics of pressure versus resistance change in three cycles, (c) Input –output characteristics of pressure versus strain by simulation, standard strain gauge experimental and RGO strain gauge experimental
Nagarjuna Neella, Manjunath. M.S, K. Rajanna, M.M.Nayak. "Reduced Graphene Oxide nanosheets based strain sensor for pressure transducers and method therefore".