Wheat is the most important cereal crop in Iran, and its annual production is about 14 million tons annually. Part of the harvested product is wasted due to wear and tear and poor adjustment, and the heavy weight of the John Deere combine harvester. It is one of the most important factors that affect harvest loss. Therefore, the stress and strain of the ferris wheel and helix are determined according to the ferris wheel rotating speed using Abaqus software, the combine harvester weight is reduced, and finally, an optimal system is designed. Therefore, the forces acting on the ferris wheel and helix modeling for the optimization and better design of the combine head will help to reduce wheat loss to increase the useful life of the ferris wheel components and combine helix, in addition to harvesting. The results showed that as much as the humidity of the crop increases, the header loss decreases to a great extent. The natural loss was reported at 6.57% with 11% humidity, while there is no significant difference between 14% and 17% humidity. The effect of the kinematic index was significant in low humidities, but the effect of the kinematic index on platform collapse was not significant in high humidities. The maximum header loss on the platform occurred in the kinematic index of 1.4 and humidity of 11% of wheat, and the minimum header loss occurred in the kinematic index of 1.1 and humidity of 17%. As a result, total combine harvester header loss includes the natural loss in the field, loss on the platform, and loss at the end of the combine harvester. In general, the effect of the kinematic index on harvest loss is insignificant, especially in the humidity of 11 and 12.5 percent. As the crop humidity increases, its loss decreases noticeably, but its efficiency increases with 17% humidity due to the increase of header loss from the end. Minimum loss occurs at and kinematic index with 14% humidity. In general, the effect of the kinematic index on crop shedding is negligible, especially in 11 and 12.5 percent humidity. As a result, crop moisture is 14%, and the kinematic index is 1.3. It is the best condition for harvesting by John Deere 1055 Combine harvesters in the Divandareh region (Kurdistan province).
