西甜瓜移栽机顶钵-接苗式取苗装置设计与试验

Design and Experiment of Seedling Pick-up Device with Ejecting Pot-Receiving Seedling for Watermelon and Cantaloupe Transplanter

摘要:

西甜瓜钵苗茎秆脆嫩、叶展角大,目前全自动移栽机的取苗装置在作业时容易造成秧苗损伤,且整体运行较不稳定,这些因素直接影响了取苗成功率。设计了一种顶钵-接苗式取苗装置实现西甜瓜钵苗低损伤、高效率移取。以“西州蜜25号”哈密瓜钵苗为研究对象,采用顶钵与接苗的取苗方式,设计配套气动控制系统以实现取苗与投苗的协同作业。针对顶钵过程进行力学分析,得出影响取苗成功率的关键因素为顶针直径、长度及顶针速度。通过综合运用ADAMS进行运动轨迹仿真与FluidSIM-P3.6进行气动系统仿真,对所提出结构设计及气动时序控制策略的合理性进行了验证。结果表明,该设计方案能确保取苗装置各部件实现高效协同作业。进一步采用EDEM模拟顶钵过程,在确定顶针参数研究区间的基础上开展仿真试验,优化取苗效果。通过方差分析与响应面分析,获得最优顶苗装置中顶针参数组合为:顶针直径1.4mm、顶针长度20mm、顶针速度150mm/s。搭建移栽取苗台架试验,试验结果表明:该参数组合下取苗成功率达94.50%,钵苗损失率为5.94%,未观测到茎秆损伤现象,满足西甜瓜移栽机对低损伤、高效率取苗的作业需求。

Abstract:

Watermelon and cantaloupe seedling pots, characterized by their tender stems and expansive foliage, present challenges for existing fully automated transplanters, including low pickup success rates, high damage rates, and poor operational stability. This study aims to address these issues by designing pick-up device with ejecting pot-receiving seedling capable of low-damage, high-efficiency removal of watermelon and cantaloupe seedlings. This study used “ Xizhoumi 25 ” cantaloupe seedlings as test samples, and the device adopted sequential lifting-and-grasping with intermittent seedling placement. A corresponding pneumatic control system was designed. Through ADAMS motion trajectory simulation and FluidSIM-P3. 6 pneumatic system analysis, the structural design and pneumatic timing control strategy were validated, ensuring high operational success rates. A mechanical analysis model for the lifting process was established, identifying the primary factors influencing successful seedling retrieval as the diameter, length, and speed of the lifting pins within the device. EDEM simulation methods were employed to analyse the lifting process. Based on determining the research range for pin diameter, length, and speed, a simulation test plan for the lifting process was constructed by using Box-Behnken experimental design methodology to ensure low-damage seedling retrieval. Through variance analysis and response surface analysis, the optimal combination of ejector pin parameters was determined as: pin diameter of 1. 4 mm, pin length of 20 mm, and pin speed of 150 mm/ s. Field trials using a transplanting seedling extraction rig confirmed that this parameter combination achieved a 94. 50% seedling extraction success rate with a 5. 94% seedling loss rate. No stem damage was observed, demonstrating suitability for low-loss, high-efficiency seedling extraction by watermelon and melon transplanters.