全自动单摆式蔬菜钵苗取喂苗系统研制

为实现蔬菜钵苗高效、稳定移栽，在分析现有全自动移栽机取喂苗系统研究现状的基础上，该研究提出了一种全自动单摆式取喂苗系统。该系统通过苗盘输送机构、纵移机构实现穴苗盘在倾斜平面内的移位，采用往复机构和夹苗机构实现取苗、喂苗。对夹苗机构等关键机构进行参数设计和运动学分析，确定了其结构参数。综合考虑影响取喂苗性能的相关因素，以苗株种类z、基质含水率w、取苗深度h和工作气压p为试验参数，以取苗成功率S1和苗株完整率S2为评价指标，在双行移栽、90株/min取苗效率下进行多因素正交试验。试验结果表明，苗株基质含水率对取苗成功率和完整率影响最大，贡献率分别为58.92%和50.58%，其次是取苗深度；当苗株为番茄苗，基质含水率35%，取苗深度40 mm，气缸工作气压为0.4 MPa时，取喂苗效果最佳，取苗成功率为98.61%，苗株完整率为97.22%。研究结果可为移栽机的机构优化及自动化控制提供理论参考。

Development of automatic single pendulum vegetable pot seedling picking and feeding system

Abstract: Plug seedlings can be used to alleviate the negative effect of severe weather on crops production, further to achieve high and stable yield, and improve land utilization. At present in China, semi-automatic transplanting machines are mainly used with low degree of automation and high labor intensity. The mechanized operation of automatic transplanter can reduce the influence of human factors, and improve the overall benefits, indicating a main trend in current development of agricultural planting mechanization. The seedling feeding system is the crucial part of an automatic transplanter. Most previous studies focused on various schemes, such as clamping, ejection, insertion, and pneumatic type. Different types of automatic transplanting machines have also been developed, however, there are still some problems, including the high seedling damage rate, low seedling retrieval efficiency, and relatively low adaptability to seedling plants. This study proposed an automatic symmetrical simple pendulum-type seedling system, mainly composed of the seedling plate conveying, longitudinal moving, rotating, reciprocating, seedling mechanism, and power control system. Kinematics analysis was performed on the reciprocating, rotating and seedling mechanism, and the MATLAB platform was used to calculate the simulation solution, where the structural parameters of each key mechanism were determined. The key mechanisms of seedling retrieval system were driven by stepping motors and cylinders that controlled by a PLC. In order to explore the effects of various parameters on the performance of seedlings in the design of test plan, the seedling efficiency was tested at 90 plants/min, and the test parameters were selected, including the seedling species z, substrate water content w, seedling depth h, and working pressure p. A multi-objective orthogonal test was carried out, where the success rate, S1 and the seedling integrity rate, S2, were taken as the evaluation indicators of seedling transplanter system. The experimental results showed that the moisture content had the greatest influence on the seedling success rate of seedling extraction, and the seedling integrity rate of seedling plants, reached 58.92% and 50.25%, respectively, followed by the insertion depth. The optimal system was achieved with the best seedling effect, when the seedling type was tomato seedling, where the moisture content was 35%, the depth was 40mm, and the air pressure was 0.4 MPa. The success rate of seedling removal, and the intact rate of seedling plants were 98.61% and 97.22%, respectively. This finding can provide a sound reference for automatic seedling removal and mechanism design of transplanting machine.