Fu Qiankun, Fu Jun, Chen Zhi, Chen Chao, Zhang Jialiang, Ren Luquan
College of Biological and Agricultural Engineering, Jilin University, Changchun, China.
Key Laboratory of Bionics Engineering, Ministry of Education, Jilin University, Changchun, China.
Front Plant Sci. 2022 Apr 12;13:852375. doi: 10.3389/fpls.2022.852375. eCollection 2022.
The effect of root anchorage on corn stalk is the main cause of difficulties in stalk lifting and ear picking of lodged corn. To quantify the forces on the stalks caused by root anchorage in corn harvesting, a root force measurement system was designed and applied in this study. The bending moment and torsional moment on the upright and lodged corn stalks were measured in corn harvesting with the designed system and the results were compared with the manually measured failure boundaries. The manually measured results showed bending moments to push down the upright stalks, to lift the lodged corn stalks, and to slip the lodged corn stalks were 35.12, 23.33, and 40.36 Nm, respectively, whereas the torsional moments needed to twist off the upright and lodged corn stalks were 4.02 and 3.33 Nm, respectively. The bending moments that the corn header applied to the upright, forward lodged, reverse lodged, and lateral lodged corn stalks were 10.68, 22.24, 16.56, and 20.42 Nm, respectively, whereas the torsional moments on them were 1.32, 1.59, 1.55, and 1.77 Nm, respectively. The bending force was the main factor that broke the root anchorage and influenced the stalk movement of lodged corn in harvesting. By analyzing the bending moment curves on the lodged corn stalks, it was proposed that for the harvesting of corn lodged in the forward, reverse, and lateral direction, the corresponding harvester header improvement suggestions are enlarging the size of pins on the gathering chains, reducing the speed of gathering chains, and lengthening the snouts with a sleeker surface, respectively. This study provides base data for the root anchorage effect on lodged corn and provides references for the improved design of the corn harvester header.
根系固着对玉米茎秆的影响是倒伏玉米茎秆扶起和摘穗困难的主要原因。为了量化玉米收获过程中根系固着对茎秆产生的力，本研究设计并应用了一种根系力测量系统。利用该设计系统测量了直立和倒伏玉米茎秆在收获过程中的弯矩和扭矩，并将结果与手动测量的破坏边界进行了比较。手动测量结果表明，推倒直立茎秆、扶起倒伏玉米茎秆和使倒伏玉米茎秆滑动所需的弯矩分别为35.12、23.33和40.36 N·m，而拧断直立和倒伏玉米茎秆所需的扭矩分别为4.02和3.33 N·m。玉米割台施加在直立、向前倒伏、向后倒伏和侧向倒伏玉米茎秆上的弯矩分别为10.68、22.24、16.56和20.42 N·m，而施加在它们上面的扭矩分别为1.32、1.59、1.55和1.77 N·m。弯曲力是破坏根系固着并影响收获中倒伏玉米茎秆运动的主要因素。通过分析倒伏玉米茎秆上的弯矩曲线，提出对于向前、向后和侧向倒伏玉米的收获，相应的收割机割台改进建议分别是增大输送链上销子的尺寸、降低输送链速度以及延长表面更光滑的导板。本研究为根系固着对倒伏玉米的影响提供了基础数据，并为玉米收割机割台的改进设计提供了参考。
