# Simulation of the Rollover Angle of a Self-Propelled Radish Harvester for Different Load Conditions
## 3 Results and Discussion
### Improvement of Rollover Angle for the Radish Harvester Considering Additional Weight  
To solve the problem in the previous section, a weight (50, 100, 150 kg) was installed at three positions (front, center, and rear). The maximum rollover angles for the weights at the front were around 60.96, 60.83, and 59.92\({}^{\circ}\) at deflection angles of 45, 30, and 45\({}^{\circ}\) for 50, 100, and 150 kg, respectively. The minimum rollover angles were 31.71, 31.64, and 33.25\({}^{\circ}\) at deflection angles of 180\({}^{\circ}\) for 50, 100, and 150 kg, respectively. The results are shown in Figure 10a-c. Therefore, if an additional load of at least 50 kg or more is installed at the front, the rollover of a wider area than the standard overturning angle can be satisfied, and the rollover criterion for the radish harvester was met. Figure 10: The rollover angles for the attached weights at the front of the radish harvester: (**a**) 50 kg, (**b**) 100 kg, and (**c**) 150 kg. Figure 9: The verification of the simulation of first and second rollover angles of the radish harvester for the defection angles of 0 and 180\({}^{\circ}\). In the case of the attached weights at the center of the radial harvester, the maximum rollover angles were approximately 61.04, 62.16, and 62.09\({}^{\circ}\) at a deflection angle of 45\({}^{\circ}\) for 50, 100, and 150 kg, respectively. For a deflection angle of 180\({}^{\circ}\), the minimum longitudinal overturning angles were 29.19, 29.75, and 30.24\({}^{\circ}\) for 50, 100, and 150 kg, respectively. The results are shown in Figure 11a-c. Unlike the additional load arranged at the front, an additional load at the center must be at least 150 kg to satisfy the standard overturning angle. Figure 12 shows the rollover angles when the weights were attached at the rear of the radial harvester. The maximum rollover angles at a deflection angle of 45\({}^{\circ}\) were 61.04, 62.16, and 62.09\({}^{\circ}\) for 50, 100, and 150 kg, respectively. For a deflection angle of 180\({}^{\circ}\), the minimum rollover angles for 50, 100, and 150 kg were 29.19, 29.75, and 30.24\({}^{\circ}\), respectively. When the additional load was placed at the rear, results were similar to those for loads placed at the center but different from those at the front. If an additional load is installed at the rear of the radial harvester, a weight of at least 150 kg must be used to satisfy the standard overturning angle. Table 3 shows the rollover angles for different additional weights on different positions of the radial harvester. In the range of 0 to 180\({}^{\circ}\), it was observed that the rollover angle reached dramatically from 46.2\({}^{\circ}\) at the deflection angle of 0\({}^{\circ}\) to 63.28\({}^{\circ}\) at the deflection angle  
Figure 11: The rollover angles for the attached weights at the center of the radial harvester: (**a**) 50 kg, (**b**) 100 kg, and (**c**) 150 kg. Figure 12: The rollover angles for the attached weights at the rear of the radial harvester: (**a**) 50 kg, (**b**) 100 kg, and (**c**) 150 kg. of 45\({}^{\circ}\), then the tilt angle of the radish harvester sharply decreased until the deflection angle increased up to 180\({}^{\circ}\). However, in the range of deflection angles of 180-315\({}^{\circ}\), the rollover angle tended to increase as the deflection angle increased. The reason was that the weight distribution of the radish harvester was skewed to the left where the conveyor belt of the harvester was located, and the rollover angle was lower when the conveyor belt of the harvester moved to the pivot point (180\({}^{\circ}\)). The condition that did not satisfy the criterion angle of 30 degrees in all conditions was the 180\({}^{\circ}\) deflection condition. When the additional weights of 50 and 100 kg were installed, the weight must be placed in the front to satisfy the standard overturning angle, which means the target angle of 30 degrees. Conversely, the standard overturning angle was not satisfied when additional weights were installed in the center or rear.