# Precision Agriculture: Assessment of Ergonomic Risks of Assisted Driving System
## 3 Results  
The tests were conducted by 10 operators, who were male and right-handed, with an average age of 37.1 \(\pm\) 9.7 years, height of 1.78 \(\pm\) 3.1 m, weight of 76 \(\pm\) 7.7 kg, and BMI of 23.72 \(\pm\) 2.9 kg/m\({}^{2}\), five years of experience in the agricultural practices of soil processing; two (20%) people played sports (see Table 1).  
The ANOVA results showed statistically significant (\(p\)\(<\) 0.01) differences in electromyographic and barometric values related to the change in the angle of the display.  
\begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Sample Characteristics**} \\ \hline Age (years) & 37.1 \(\pm\) 9.7 \\ Right-handed & 100\% (n = 10) \\ Male & 100\% (n = 10) \\ Height (m) & 1.78 \(\pm\) 3.1 \\ Weight (kg) & 76 \(\pm\) 7.7 \\ BMI (kg/m\({}^{2}\)) & 23.72 \(\pm\) 2.9 \\ A least 5 years in the field & 100\% \\ Played sports (2 h/week) & 20\% (n = 2) \\ \hline \hline \end{tabular}
\end{table}
Table 1: Main characteristics of the operators.  
In particular, with regard to sEMG, we observed a significant increase in muscle activation for SH_LX, SH_RX, BK_LX, and BK_RX as the display positioning angle increased (30\({}^{\circ}\) > 50\({}^{\circ}\) > 80\({}^{\circ}\)) (see Figure 5).  
No significant difference was observed between the operators.  
With regard to the barometric analysis, the display position at 80\({}^{\circ}\) generated a significantly higher increase in Pavg, Pmax, and NC130_400 than the other angles, i.e., 30\({}^{\circ}\) and 50\({}^{\circ}\). Also, the display position at 50\({}^{\circ}\) generated values significantly greater in Pavg, Pmax, and NC130_400 than at 30\({}^{\circ}\) (see Figure 6).  
No significant difference was observed between the operators.  
Figure 5: Scatter plots and box plots. Each graph represents the distribution of the frequency (Hz) observed from surface electromyographic (sEMG) measurements of specific body regions (SH_LX, SH_RX, BK_LX, and BK_RX) during the tests at different angles of display: 30\({}^{\circ}\), 50\({}^{\circ}\), and 80\({}^{\circ}\). Orange dots: sEMG at 30\({}^{\circ}\); purple dots: sEMG at 50\({}^{\circ}\); and green dots: sEMG at 80\({}^{\circ}\).  
Figure 6: Scatter plots and box plots. Each graph represents barometric data (g/cm\({}^{2}\)) relating to three different variables, namely Pavg, Pmax, and NC130_400, during the tests at different angles of display: 30\({}^{\circ}\), 50\({}^{\circ}\), and 80\({}^{\circ}\). Orange dots: measurement at 30\({}^{\circ}\); purple dots: measurement at 50\({}^{\circ}\); and green dots: measurement at 80\({}^{\circ}\).  
The IRT did not show a significant increase in the temperature at the DL and DR regions at the end of observation (T1) compared to T0. Only in the DR region measurement was an increase in temperature observed at the end of the test (T1), with the display positioned at 80\({}^{\circ}\). No significant difference was observed between the operators (see Table 2).  
Regarding the lumbar region, we observed a significant increase in the temperature at the LL at 80\({}^{\circ}\) of the display, and there was no significant increase at the LR at 50\({}^{\circ}\) and 80\({}^{\circ}\) at the end of observation (T1) compared to T0. However, an increase in temperature was observed with an increase in the degree of display to T1 compared to T0. No significant difference was observed between the operators (see Table 3).