## 3 Results and Discussion
### Load and Instrumental Signal Behavior in the Bending Tests
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Sensor** & **V\({}_{\text{smax}}\) (mV)** & **CV (\%)** & **V\({}_{\text{so}}\) (mV)** & **CV (\%)** & **V\({}_{\text{s}}\)(P\({}_{\text{max}}\)) (mV)** & **CV (\%)** & **P\({}_{\text{max}}\) (N)** & **CV (\%)** & **DP\({}_{\text{o}}\) (mm)** & **CV (\%)** \\ \hline G1 & 984.7 & 0.7 & 154.4 & 8.4 & 707.0 & 3.3 & 0.056 & 4.7 & 0.203 & 17.9 \\ G2 & 703.5 & 0.3 & 284.2 & 0.2 & 670.4 & 6.0 & 0.018 & 2.0 & 0.216 & 32.5 \\ G3 & 1159.6 & 0.5 & 348.0 & 3.1 & 872.8 & 0.5 & 0.046 & 5.1 & 0.092 & 38.2 \\ G4 & 906.8 & 0.2 & 363.1 & 1.9 & 903.8 & 0.3 & 0.021 & 1.7 & 0.291 & 12.1 \\ G5 & 1317.9 & 0.3 & 239.1 & 22.9 & 1052.3 & 3.7 & 0.037 & 7.0 & 0.233 & 30.4 \\ G6 & 1746.4 & 0.0 & 876.5 & 7.5 & 1530.8 & 3.4 & 0.070 & 4.5 & 0.095 & 94.6 \\ \hline Average & 1014.5 & 0.4 & 277.7 & 7.3 & 841.3 & 2.8 & 0.035 & 4.1 & 0.207 & 26.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Experimental values of generic parameters for load and instrumental signal. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Intercept (mN)**} & \multicolumn{4}{c}{**Slope (mN/mV)**} & \multicolumn{4}{c}{**Vsoe**} & **Diff** \\ \hline
**Sensor** & **Lower** & **Limit** & **Value** & **Upper** & **Low** & **Limit** & **Value** & **Upper** & **Prob-F** & **R\({}^{2}\)** & **(mV)** & **(\%)** \\ \hline G1 & \(-\)19.57 & \(-\)18.98 & \(-\)18.40 & 0.0000 & 0.1110 & 0.1124 & 0.1138 & 0.0000 & 0.999 & 168.96 & 9.4 \\ \hline G2 & \(-\)15.40 & \(-\)13.45 & \(-\)11.50 & 0.0000 & 0.0529 & 0.0578 & 0.0627 & 0.0000 & 0.935 & 232.78 & \(-\)18.1 \\ \hline G3 & \(-\)42.91 & \(-\)41.19 & \(-\)39.48 & 0.0000 & 0.1083 & 0.1113 & 0.1143 & 0.0000 & 0.997 & 370.15 & 6.4 \\ \hline G4 & \(-\)11.68 & \(-\)10.78 & \(-\)9.87 & 0.0000 & 0.0380 & 0.0397 & 0.0414 & 0.0000 & 0.977 & 271.46 & \(-\)25.2 \\ \hline G5 & \(-\)13.46 & \(-\)12.65 & \(-\)11.84 & 0.0000 & 0.0533 & 0.0546 & 0.0559 & 0.0000 & 0.997 & 231.62 & \(-\)3.1 \\ \hline G6 & \(-\)188.05 & \(-\)170.55 & \(-\)153.06 & 0.0000 & 0.1754 & 0.1917 & 0.2079 & 0.0000 & 0.975 & 889.82 & 1.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Statistical parameters of the linear model between load and instrumental signal (\(p\) < 0.8 Pmax). In Figures 4 and 5, it is observed that the sensors were subjected to large lateral displacements through the two-point bending tests. Similarities and differences between the average load-displacement and instrumental signal-displacement curves were found. A non-linear relationship between both the load and the instrumental signal and the lateral displacement was observed in all tests performed. The test repetitions showed a consistent trend for the load and the instrumental signal, namely, a third-order polynomial trend line for the whole range of the lateral displacement of the sensor. Furthermore, it is observed that the slope of the load-displacement curve changes sign when the lateral displacement of the sensor exceeds the maximum load value (P\({}_{\text{max}}\)). In contrast, the slope of the instrumental signal-displacement curve diminishes when the lateral displacement reaches its maximum value (V\({}_{\text{smax}}\)) (see Figure 5b and Table 2). Within the SDL, a linear relationship can be observed in almost all of the responses of the average load-displacement and instrumental signal-displacement curves. This linear relationship can be extended beyond the SDL value up to lateral displacements induced by loads close to 80% of the maximum load, owing to the flexibility of the material used (strain gauges). This is consistent with the classical beam theory or the plate theory, as well as with the hypothesis proposed in this study. In addition, minimum slopes for the load-displacement and instrumental signal-displacement curves were observed for loads lower than 20% of the maximum load.