*3.1. Results of Unpressed Vines Experiment*

According to the experimental method, the experimental results of the peanut diggerinverter under the condition of unpressed vines are shown in Table 3, and the range analysis and variance analysis are shown in Figure 5 and Table 4.


**Table 3.** Experimental design and results of unpressed vines.

**Figure 5.** Range analysis of unpressed vines experiment results; (**a**) Pm, (**b**) Ps, (**c**) Pf.

**Table 4.** Experimental variance analysis of unpressed vines.


(Pf) R square = 0.995, (Pm) R square = 0.964, (Ps) R square = 0.988. Note: The critical value of significant judgment F0.01(2,2) = 99, F0.05(3,3) = 19, F0.1(2,2) = 9. \* Indicates that the factors have some influence on the test index (0.05 < *p* ≤ 0.1), \*\* indicates that the factors have a significant influence on the test index (0.01 < *p* ≤ 0.05).

The variable R stands for range, and the range of a factor is the difference between the maximum and minimum values of the mean values of each level of the factor, t1 represents the average value of experimental results at the level of 1 for each experimental factor, t2 represents the average value of experimental results at the level of 2 for each experimental factor, and t3 represents the average value of experimental results at the level of 3 for each experimental factor.

According to the range analysis in Figure 5a, the order of influence of all factors on the rate of vines inverting is as follows: A > B > C. According to the comprehensive comparability, the higher the average value of each factor group of the rate of vines inverting, the better the level of factor. Moreover, according to the variance results in Table 4, the impact of all factors on the rate of vines inverting is extremely significant, so the maximum horizontal combination is A3B2C2. Similarly, according to the range analysis in Figure 5b, the order of influence of all factors on the rate of buried pods is as follows: A > B > C. From comprehensive comparability, it can be seen that the lower the average value of each factor group in the rate of buried pods, the better the level of the factor. Moreover, according to variance results in Table 4, it can be seen that the traveling speed of the tractor has a significant impact on the rate of buried pods, while the line speed of the conveyor chain and the line speed of the inverting roller have no significant impact on the rate of buried pods. At the same time, A1 and A2 are the same, so the minimum horizontal combination is chosen as A2B1C3 by mechanical performance. Similarly, from the range analysis in Figure 5c, it can be seen that the order of influence of all factors on the rate of fallen pods is as follows: A > C > B. From the comprehensive comparability, it can be seen that the lower the average value of each factor group for the rate of fallen pods, the better the level of that factor. Moreover, from the variance results in Table 4, it can be seen that the influence of the traveling speed of the tractor and the line speed of the inverting roller on the rate of fallen pods is extremely significant, and the line speed of the conveyor chain has a significant effect on the rate of fallen pods, so the minimum horizontal combination is A1C1B2.

According to the comprehensive balance method for multi-index data analysis of an orthogonal experiment, the above analysis results are summarized, and the summary table is shown in Table 5.


**Table 5.** Summary of results of unpressed vines.

As can be seen from Table 5, factor A is the most important at the level of A2, followed by factor C at the level of C3, and then factor B at the level of B2. In conclusion, the best horizontal combination can be A2C3B2, that is, the traveling speed of the tractor is 0.9~1.1 m/s, the line speed of the inverting roller is 2.12 m/s, and the line speed of the conveying chain is 1.02 m/s. In order to further verify the operation effect, three repeated experiments were carried out under the above optimal working parameters: the average traveling speed of the tractor was 1.06 m/s, the rate of vines inverting was 71.07%, the rate of buried pods was 0.2%, and the rate of fallen pods was 0.22%. The rate of buried pods and the rate of fallen pods were far less than the identification standard of the peanut harvester.
