## 3 Results and Discussion
### Operating Speed  
The proposed machine adopted a 4-jaw type structure and MHL2 pneumatic gripper to perform clamping and beveling operations, the operational speed of which is shown in Table 4. For a single operation, eggplant seedlings take an average of 17.56 s, and tomato seedlings an average of 16.66 s. This means that it takes an average of 34.22 s to obtain 4 scion seedlings and 4 stock seedlings. It can be concluded that the average treatment time for a single eggplant and tomato seedling is 4.39 s and 4.17 s, respectively\(-\)that is, it takes an average of 8.56 s to process the scion and stock seedlings of a single grafted seedling.  
Based on the above, the short-knife and long-knife oblique cutting structures in this study can complete oblique cutting of 346 and 404 eggplant seedlings in one hour, respectively. According to the \(t\)-test, the long-knife type is significantly larger than the short-knife type (\(p\leq 0.05\)). Using the short-knife and long-knife oblique cutting structures, 362 and 384 tomato seedlings can be obliquely cut in one hour, respectively. Although the long-knife type can complete more oblique cuts, there is no significant difference in statistical analysis (\(p>0.05\)) (Figure 10).  
The overall average operating efficiency of the proposed machine is shown in Table 5. Under uninterrupted operation, the time required to complete a plate of eggplant and  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Seedlings**} & \multicolumn{2}{c}{**Average Operating Time**} \\ \cline{2-3}  & **Single (s)** & **A Seeding (s)** \\ \hline Eggplant stock & 17.56 \(\pm\) 0.98 & 4.39 \(\pm\) 0.25 \\ Tomato scion & 16.66 \(\pm\) 0.36 & 4.17 \(\pm\) 0.09 \\ Total & 34.22 \(\pm\) 1.26 & 8.56 \(\pm\) 0.32 \\ \hline \hline \end{tabular}
\end{table}
Table 4: The average single operation time of the proposed machine using a 4-jaw type structure and MHL2 pneumatic gripper.  
Figure 10: The number of seedlings that can be processed by two oblique cutting structures within one hour of operation.  
tomato seedlings in the short-knife and long-knife modes is 14 min 34 s and 15 min 5 s, respectively. Based on the \(t\)-test analysis, there is no significant difference in the working time of the two types, as the speed and path of the robot arm are the same; only the coordinate positions differing due to the oblique cutting structure of the two structures. However, this does not affect the results.  
When this machine is paired with a grafter who uses a casing to graft, the time required to complete a plate of grafted seedlings using the short knife and long knife is 38 min 19 s and 32 min 10 s, respectively. Based on the \(t\)-test analysis, the working time of the short-knife type is significantly longer than that of the long-knife type. Because the success rate of the short knife is lower than that of the long knife, grafters need to do more debugging work - such as handling seedlings that have not been beveled - resulting in extended processing times. It is also estimated that the grafter can complete 163 and 194 grafted seedlings in the short-knife and long-knife modes, respectively, after using the device for one hour, as shown in Figure 11. Based on the \(t\)-test analysis, the number of grafted seedlings of the long-knife type is significantly more than that of the short-knife type (\(p\leq 0.05\)).  
From the above results, it is evident that the short-knife and the long-knife types do not affect the time for the machine itself to process scion and stock seedlings, but it does affect the smoothness of the grafter when using the casing grafting process, the long-knife type more efficiently grafting seedling.