# Novel Resistive Sensor Design Utilizing the Geometric Freedom of Additive Manufacturing
## 3 Results
### Resistive Behavior
\begin{table}
\begin{tabular}{c c||c c||c c} \hline \hline \multicolumn{1}{c}{**Gap Size**} & \multicolumn{1}{c}{**Velocity**} & \multicolumn{1}{c}{**Resistance (\(\Omega\)) of**} & \multicolumn{1}{c}{**Resistance (\(\Omega\)) of**} & \multicolumn{1}{c}{**Resistance (\(\Omega\)) of**} \\ \multicolumn{1}{c}{**(mm)**} & \multicolumn{1}{c}{**(mm/min)**} & \multicolumn{1}{c}{**Variant 1**} & \multicolumn{1}{c}{**Variant 2**} & \multicolumn{1}{c}{**Variant 3**} & \multicolumn{1}{c}{**Variant 4**} \\ \hline \multirow{3}{*}{0.3} & 5 & 379.01 \(\pm\) 1.81 & 349.51 \(\pm\) 2.85 & 339.64 \(\pm\) 2.91 & 369.54 \(\pm\) 7.01 \\  & 10 & 383.87 \(\pm\) 3.18 & 345.60 \(\pm\) 2.50 & 341.41 \(\pm\) 2.49 & 353.37 \(\pm\) 3.11 \\  & 20 & 406.44 \(\pm\) 3.54 & 342.56 \(\pm\) 3.73 & 347.43 \(\pm\) 5.47 & 350.44 \(\pm\) 1.43 \\ \hline \multirow{3}{*}{0.5} & 5 & 560.32 \(\pm\) 4.03 & 469.12 \(\pm\) 9.24 & 633.45 \(\pm\) 17.11 & 622.88 \(\pm\) 5.93 \\  & 10 & 553.52 \(\pm\) 0.69 & 455.27 \(\pm\) 9.58 & 652.59 \(\pm\) 4.69 & 642.16 \(\pm\) 14.99 \\ \cline{1-1}  & 20 & 559.84 \(\pm\) 3.53 & 461.97 \(\pm\) 3.59 & 631.50 \(\pm\) 15.98 & 653.15 \(\pm\) 2.68 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Mean values and standard deviation of resistance in ohms, calculated from the lowest resistance value reached in each of the five actuations for each measurement. Note that due to resistive path shortening, a high force and deformation coincide with a low, rather than a high extreme in resistance. The arrows indicate the order in which measurements were performed. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Gap Size (mm)**} & \multirow{2}{*}{
\begin{tabular}{c} **Velocity** \\ **(mm/min)** \\ \end{tabular} } & \multicolumn{1}{c}{**Relative Peak**} & \multicolumn{1}{c}{**Relative Peak**} & \multicolumn{1}{c}{**Relative Peak**} & \multicolumn{1}{c}{**Relative Peak**} \\  & & **Resistance (\%)** & **Resistance (\%)** & **Resistance (\%)** & **Resistance (\%)** \\  & & **(Variant 1)** & **(Variant 2)** & **(Variant 3)** & **(Variant 4)** \\ \hline \multirow{3}{*}{0.3} & 5 & 19.48 & 29.47 & 17.55 & 21.98 \\  & 10 & 19.72 & 28.56 & 17.43 & 18.68 \\  & 20 & 23.79 & 27.23 & 27.08 & 18.14 \\ \hline \multirow{3}{*}{0.5} & 5 & 27.64 & 22.9 & 30.99 & 30.62 \\  & 10 & 27.24 & 22.37 & 31.81 & 31.57 \\ \cline{1-1}  & 20 & 27.41 & 22.73 & 30.68 & 32.08 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Relative extreme values in resistance, shown as percentage of the initial resistance value R0. Figure 6: Effect of different velocities on the force-resistance behavior of the sensor. Depicted for variant 4, with a gap of 0.5 mm, at velocities 5, 10, 20, and 100 mm/min. closed, the resistive response was similar and near linear with compression for variants 1, 3, and 4, with variant 2 showing a non-linear response. Based on the test variables, this effect cannot be readily explained, and further investigation will be performed to find the cause of the observed behavior. Figure 8 displays the relationship between the applied force and resistive response for the same 0.5 mm gap size parts. Like in the distance graph, there is an initial section of force being applied that does not lead to a resistive response. Once the gap was closed, the relationship between force and resistance was initially linear and the resistive response covered the majority of the force range. Only in variants 2 and 3 was there a flattening of the curve towards the end of its deformation. Figure 9 displays the relationship between the distance the part is compressed and its resistive response, but for parts with a 0.3 mm gap size. The parts initially responded more rapidly to deformation than those with a 0.5 mm gap. The variants displayed a comparable response to a certain distance of deformation, though most of the resistive change occurred in the first millimeter of deformation. Figure 10 displays the relationship between applied force and resistive response for the parts with a 0.3 mm gap size.