# Simulation of the Rollover Angle of a Self-Propelled Radish Harvester for Different Load Conditions
## 5 Conclusions  
This study was focused on the improvement of the rollover angle of the radish harvester to ensure operational stability, safety, and comfort. In this study, a 3D model of a self-propelled radish harvester was used to simulate its rollover angle on the basis of weight conditions at the front, center, and rear of the harvester. First, the self-propelled radish harvester simulated the rollover angle under deflection angle conditions from 0\({}^{\circ}\) and 180\({}^{\circ}\), which was validated by the indoor test. The results were analyzed statistically. Then, further simulation was conducted to satisfy the standard overturning angles of the radish harvester under all conditions. The overall findings of this study were as follows:  
1. The rollover angle of the radish harvester was analyzed with contact force between the wheel and ground. It was observed that the tilt angles were slightly smaller than the standard overturning angle range at a deflection angle of 180\({}^{\circ}\). This suggested that there was a risk to stability, as the rollover angle was less than 30\({}^{\circ}\) when the radish harvester was tilted, and that improvement was needed.
2. The regression analysis of the rollover angles showed that both simulation and experimental results had a linear relationship, whereas R\({}^{2}\) was 0.911 and 0.9589, respectively. These results proved that the simulation and experimental results followed a similar trend.
3. To solve the rollover issues occurring at the deflection angle of 180\({}^{\circ}\) of the radish harvester, a simulation was performed considering the additional weights. As a result, we found that attaching additional weight to the front at a deflection angle of 180 degrees was the most effective approach for increasing the rollover angle.
4. To satisfy the standard overturning angle in all conditions, attaching an additional weight of 50 kg to the front or 150 kg to the center or rear was suggested.  
In conclusion, the stability analysis of the self-propelled radish harvester satisfied the international standard for agricultural machinery, attaching an additional weight of 50 kg to the front or 150 kg to the center or rear. The results mean that the radish harvester could be used on a field with a slope of 30\({}^{\circ}\). On the basis of the results, as well as on the literature on agricultural machinery, the user can operate the harvester at a sloping upland field with operational safety and driving comfort.  
**Author Contributions:** Conceptualization, W.-S.K., Y.-J.J. and [PERSON]; methodology, [PERSON]-[PERSON] and [PERSON]-[PERSON]; software, [PERSON]-[PERSON]; validation, W.-S.K. and M.A.A.S.; formal analysis, Y.-J.J. and M.A.A.S.; investigation, W.-S.K., Y.-S.K., S.-M.B., [PERSON]-[PERSON] and [PERSON]-Y.B.; writing--original draft preparation, W.-S.K. and M.A.A.S.; writing--review and editing, W.-S.K., M.A.A.S., [PERSON]-[PERSON] and [PERSON]-[PERSON]; visualization, W.-S.K., [PERSON]-[PERSON] and [PERSON]; supervision, [PERSON]-[PERSON] and [PERSON]-[PERSON]; project administration, Y.-J.K.; funding acquisition, Y.-J.K. All authors have read and agreed to the published version of the manuscript.  
This work was carried out with the support of \"Cooperative Research Program for Agriculture Science and Technology Development (Project No. PJ0156952022)\" Rural Development Administration, Republic of Korea.  
Not applicable.  
The data presented in this study are available within the article.  
The authors declare no conflict of interest.