Abstract: In order to improve the efficiency of vegetable grafting and reduce labor intensity and cost, the key actions and steps in the process of manual vegetable seedling grafting were sorted out in this paper, and the interaction mechanism between the seedlings and the machine was analyzed. Based on these results, we adopted twoway cutting and docking technology to design a horizontal, portable semiautomatic vegetable grafting machine. According to the practical requirements of the grafting machine, the pneumatic system was used to realize the automatic clamping, cutting, and docking actions of vegetable seedlings. Based on the input signal of sensors and the characteristics of the actuator, an Omron PLC was used as controller. The control program was written according to the operation flow of the machine. Finally, the performance of the machine was tested by experiments, the results showed that the average grafting efficiency of the grafting machine was 348 plants/h, the average grafting success rate reached 93.3%， and no grafted seedlings had been damaged during the tests. The machine structure design was reasonable, the performance was stable and reliable, and it could provide technical support for the grafted seedlings production in small and mediumsized seedling bases and farmers. It could also provide a reference for the development and application of agricultural mechanization auxiliary devices.

Key words:  vegetables, automatic grafting machine, PLC, control system

摘要： 为提高蔬菜嫁接作业效率、降低人工劳动强度和嫁接成本，对人工蔬菜苗嫁接过程中的关键动作及流程进行梳理，分析秧苗—机器互作机理，采用双向切割对接技术，设计一种卧式轻便型蔬菜苗半自动嫁接机。根据嫁接机实际使用要求，利用气动驱动方式实现蔬菜苗的自动夹持、切割和对接动作。基于传感器输入信号以及输出执行元件特点，选用欧姆龙PLC作为嫁接机控制器，并依据嫁接机作业流程编写控制程序。最后对该机器性能进行嫁接测试，结果表明，嫁接机平均作业效率为348株/h，平均嫁接成功率为93.3%，嫁接苗零损伤。该机机构设计合理，工作性能稳定可靠，与市场现有嫁接机相比成本显著降低，因此可为中小型育苗基地和农户嫁接苗生产提供技术支撑，同时可为农业机械化辅助装置的研发和应用提供参考。

关键词: 蔬菜, 自动嫁接机, PLC, 控制系统