## 4 Results and Discussion
### Static Workbench Experiment  
The stability variation coefficient of total sowing quantity and the consistency variation coefficient of sowing quantity between each port are the two most important indicators to evaluate the performance of the centralized seeding system. In the static workbench test, the values of the two less important factors were fixed, in other words, the fan air pressure was set to 2450 Pa, and the seed layer thickness was set to 45 mm. The value of the most important factor (i.e., the rotational speed of the gear disc) was set to five levels (25, 30, 35, 40, 45) r/min. The relationship between the total sowing quantity and the rotational speed was studied, and the results are shown in Table 3 and Figure 7. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Test** & **A/Seed Layer** & **B/Rotational** & **C/Fan Air** & **D/Blank** & **Seed Feeding** \\
**Number** & **Thickness** & **Speed** & **Pressure** & **Column** & **Rate (g/min)** \\ \hline
1 & 1(15) & 1(25) & 1(1960) & 1 & 355.90 \\
2 & 1 & 2(35) & 2(2450) & 2 & 352.00 \\
3 & 1 & 3(45) & 3(2940) & 3 & 501.30 \\
4 & 2(30) & 1 & 2 & 3 & 359.70 \\
5 & 2 & 2 & 3 & 1 & 345.30 \\
6 & 2 & 3 & 1 & 2 & 478.30 \\
7 & 3(45) & 1 & 3 & 2 & 326.50 \\
8 & 3 & 2 & 1 & 3 & 354.70 \\
9 & 3 & 3 & 2 & 1 & 547.80 \\ \hline k1 & 403.07 & 347.37 & 396.30 & 416.33 & \\ k2 & 394.43 & 350.67 & 419.83 & 385.60 & \\ k3 & 409.67 & 509.13 & 391.03 & 405.23 & \\ Range & 15.23 & 161.77 & 28.80 & 30.73 & \\ \hline Ranking & & & B D C A & & \\ \hline Optimal parameters & & & B\({}_{3}\) C\({}_{2}\)A\({}_{3}\) & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Results of the standard orthogonal experiment. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Seeding Rotational**} & \multicolumn{6}{c}{**Seeding Rate of Each Port (g/min)**} & \multicolumn{6}{c}{**Total Seeding Rate**} & \multicolumn{2}{c}{**Subleity Variation**} & \multicolumn{2}{c}{**Consistency Variation**} \\  & \multicolumn{1}{c}{**Test No.**} & **Port 1** & **Port 2** & **Port 3** & **Port 4** & **Port 5** & **Port 6** & **Port 7** & **(g/min)** & **Seeding Rate C\({}_{\text{VT}}\) (\%)** & **Coefficient of Seeding Rate** \\ \hline \multirow{4}{*}{25} & 1 & 44.10 & 45.70 & 46.70 & 49.10 & 46.30 & 45.50 & 47.20 & 324.60 & \multirow{4}{*}{2.37} & \multirow{4}{*}{2.83} \\  & 2 & 43.80 & 39.80 & 45.30 & 46.10 & 43.20 & 46.20 & 45.20 & 309.60 & \multirow{4}{*}{2.37} & \multirow{4}{*}{2.83} \\  & 3 & 42.90 & 45.40 & 44.80 & 45.70 & 47.40 & 44.90 & 46.80 & 317.90 & & \multirow{4}{*}{2.37} & \multirow{4}{*}{2.83} \\  & Average & 43.60 & 43.63 & 45.60 & 46.97 & 45.63 & 45.53 & 46.40 & 317.37 & & & \\  & 1 & 48.50 & 46.70 & 49.30 & 47.60 & 43.30 & 48.30 & 47.20 & 330.90 & & & \\
30 & 2 & 45.70 & 48.90 & 49.70 & 43.50 & 47.60 & 46.10 & 43.80 & 325.30 & & \\  & 3 & 46.50 & 46.70 & 47.40 & 49.70 & 46.20 & 48.70 & 45.90 & 331.10 & & \multirow{4}{*}{1.00} & \multirow{4}{*}{2.38} \\  & Average & 46.90 & 47.43 & 48.80 & 46.63 & 45.50 & 47.70 & 45.63 & 329.10 & & \\  & 1 & 54.80 & 86.50 & 52.90 & 59.40 & 54.70 & 51.60 & 53.80 & 385.80 & & \\
35 & 2 & 52.10 & 56.20 & 51.20 & 56.40 & 51.40 & 49.80 & 54.70 & 371.80 & & \\
35 & 3 & 53.00 & 54.90 & 53.80 & 57.40 & 52.60 & 48.00 & 57.60 & 377.90 & 1.85 & 4.89 \\  & Average & 53.30 & 56.57 & 52.63 & 57.73 & 52.90 & 50.00 & 55.37 & 378.50 & & \\  & 1 & 63.80 & 67.40 & 68.20 & 66.30 & 67.90 & 64.50 & 66.10 & 464.20 & & \\
40 & 2 & 62.10 & 66.90 & 67.80 & 63.80 & 64.70 & 63.60 & 68.40 & 457.30 & 0.87 & 2.44 \\  & 3 & 63.90 & 68.10 & 65.40 & 67.60 & 66.30 & 65.20 & 67.80 & 466.30 & & \\  & Average & 63.27 & 67.47 & 67.13 & 65.90 & 66.30 & 64.43 & 67.43 & 461.93 & & \\  & 1 & 72.30 & 71.30 & 81.20 & 79.60 & 79.80 & 82.10 & 72.50 & 583.60 & & \\
45 & 2 & 74.80 & 73.90 & 79.10 & 79.40 & 76.80 & 80.70 & 74.50 & 539.20 & & \\
45 & 3 & 74.90 & 74.10 & 77.90 & 78.60 & 78.10 & 76.30 & 73.80 & 533.70 & 0.56 & 3.93 \\  & Average & 74.00 & 73.10 & 79.40 & 79.20 & 78.17 & 79.70 & 73.60 & 537.17 & & \\ \hline \hline \end{tabular}
\end{table}