Abstract: In order to promote the mechanization of facility vegetable production , a kind of unmanned ditching and fertilizing machine for facility vegetable production was designed according to the agronomic requirements of “opening planting ditch, fertilizing in ditch, covering soil and stabilizing ditch” in facility vegetable production. This machine is composed of driving chassis system, ditching and fertilizing operation system, hydraulic transmission system, automatic control system, power supply system, etc., which can complete 4-6 lines of operation such as ditching, fertilizing, soil covering, and stabilizing ditch at one time. During the operation, the mobile phone APP communicates with the PLC on the machine through the operators NB-IoT, and the PLC controls the start and stop of the diesel engine and the work of the hydraulic transmission system, and then the hydraulic transmission system drives the whole machine to travel and ditch and fertilize. In the process of design, the 3D model of the machine was built by UG software and the structural strength of the main stressed parts was analyzed, and the analysis showed that the frame stiffness needed to be strengthened appropriately. The field test results show that the depth of ditch fertilization is 90-130 mm, the fertilizer finely divided and evenly mixed degree is ≥90%, the uniformity of fertilization is ≥90%, the thickness of the covering soil is ≥50 mm, the width of the ditch bottom soil surface is about 100 mm, the depth of the ditch bottom soil surface is 30-70 mm, the stability of the ditch shape is ≥95%, the duration of continuous fertilization ≥ 1 greenhouse, and the distance of remote control is ≥2 km, which means that all the indicators meet the design requirements. This study is of great significance to improve the quality and efficiency of ditching and fertilizing operations, and to reduce labor intensity and labor cost in facility vegetable production.

Key words: facility vegetables, ditching machine, fertilizing machine, hydraulic transmission, PLC, NB-IoT

摘要： 为促进设施蔬菜生产机械化，针对设施蔬菜生产中“开种植沟、沟内施肥、覆土稳沟”的农艺要求，设计一种设施蔬菜生产无人开沟施肥机。该机由行驶底盘系统、开沟施肥作业系统、液压传动系统、自动控制系统、供电系统等组成，一次可完成开沟、施肥、覆土、稳沟等作业4~6行。作业时，由手机APP经过运营商的NB-IoT与该机上的PLC通信，并由PLC控制柴油发动机启停及液压传动系统工作，再由液压传动系统驱动整机行驶及开沟施肥作业。设计过程中，通过UG软件对该机进行三维建模并对主要受力部件进行结构强度分析，得出机架的刚度需适当加强。田间试验结果表明：开沟施肥深度90~130mm、肥料细碎匀混度≥90%、施肥均匀度≥90%、覆土厚度≥50mm，沟底土面宽度约100mm、沟底土面深度30~70mm、沟形稳固度≥95%，持续施肥时长≥1个大棚，远程控制距离≥2km，即各项指标符合设计要求。该研究对提高设施蔬菜生产中开沟施肥作业的质量和效率、降低劳动强度和劳动成本，有着重要意义。

关键词: 设施蔬菜, 开沟机, 施肥机, 液压传动, PLC, NB-IoT