Resumen
In order to address the common difficulties in pulling and harvesting whole cotton stalks, such as high pulling resistance, high miss-pulling rate, and high breakage rate, which severely hinder the recycling of cotton stalks, three different pulling mechanisms with different pulling principles (wrapping-type pulling mechanism, clamping-type pulling mechanism, transverse roller-type pulling mechanism) were designed. The pulling force on cotton stalks during the pulling process of the three different roller-type pulling mechanisms was compared and analyzed, clarifying the mechanism of roller-type whole cotton stalk pulling mechanisms and identifying situations with optimal pulling force. Field comparative experiments were conducted to compare the working performance of different roller-type pulling mechanisms in the field, and a comprehensive analysis of two key indicators in pulling cotton stalks, miss-pulling rate and breakage rate, was carried out. The results showed that the pulling method and pulling force of the pulling mechanism played a crucial role in the successful pulling of cotton straws. Comparative analysis of the three pulling mechanisms revealed that the clamping-type pulling mechanism had the highest pulling force. The standard deviation means of the missed pull rates for mechanisms X1, X2, and X3 were 0.83%, 0.59%, and 0.43%, respectively, while the standard deviation means of the breakage rates were 1.48%, 1.79%, and 0.49%, respectively. The enveloping-type pulling mechanism had a higher missed pull rate with an average of 8.32%, and the clamping-type pulling mechanism resulted in excessive breakage of cotton straw during operation, with an average breakage rate of 14.10%. In contrast, the transverse roller-type straw pulling mechanism performed the best in the field performance test, as it did not require precise alignment and had an average missed pull rate of 4.55% and an average breakage rate of only 7.55%. Considering the practical needs of agriculture production, the transverse roller-type straw pulling mechanism is recommended as the pulling device for cotton straw harvesting. The research results can provide a reference for the design selection of whole-plant straw pulling mechanisms.