Abstract: Cutting device is a key part in orderly harvesting Chinese little greens. In order to reduce the loss and damage rate during this process and improve harvest efficiency, this paper measured and analyzed a series of mechanical properties of Chinese little greens stalks under compression condition by static measurement method. The results showed that the range of stalk axial elastic modulus was 3.15~3.91 MPa, and radial elastic modulus range was 20.24~20.99 MPa. The relevant values of the mechanical properties of Chinese little greens stalks were combined with the finite element analysis software ANSYS to establish a stalk material library, and then the 3-dimensional modeling software SolidWorks was used to construct the model for cutting process, which was imported into ANSYS for displaying dynamics analysis and verifying the results obtained from finite element analysis in field experiment. The comparison results showed that when knife reciprocating speed was more than 0.40 m/s, the stalks of Chinese little greens could be effectively cut with tidy cutting stubble and smooth fractures. These analysis results provided theoretical basis for future designing and parameter optimization of the components of cutting Chinese little greens.

Key words: stalks of Chinese little greens, mechanical properties, compression test, cutting model, finite element analysis, field test

摘要： 鸡毛菜切割部件是鸡毛菜有序收获过程中的关键部件，为了降低有序收获过程中的损失率和损伤率，提高收获效率，采用静态测量法，应用质构仪对鸡毛菜茎秆在压缩条件下的一系列力学特性参数进行测定分析，得到在压缩条件下鸡毛菜茎秆轴向弹性模量范围为3.15~3.91 MPa，径向弹性模量范围为20.24~20.99 MPa。结合试验所得鸡毛菜茎秆力学特性相关数值在有限元分析软件ANSYS中建立鸡毛菜茎秆材料库，再利用三维建模软件SolidWorks建立切割过程模型，将之导入ANSYS中进行显示动力学分析，并对有限元分析所得结果进行田间试验验证，对比结果显示：当割刀往复速度v大于0.40 m/s时，能有效完成对鸡毛菜茎秆的切断过程，且割茬整齐、断口平滑、无扯皮现象，分析结果为后续鸡毛菜切割部件的设计及参数优化提供理论依据。

关键词: 鸡毛菜茎秆, 力学特性, 压缩试验, 切割模型, 有限元分析, 田间试验