【作者】 张超；

【导师】 尹大庆； 马君；

【作者基本信息】 东北农业大学 ， 机械硕士（专业学位）， 2025， 硕士

【摘要】 中国是世界上蔬菜种植面积和产量最大的国家,其中超过60%的蔬菜种植采用育苗移栽的方式。随着蔬菜产业的发展,全自动移栽机械的研发已成为国内外蔬菜产业发展的首要任务。目前,探入取钵式取苗机构在蔬菜钵苗移栽领域得到了广泛应用,然而该机构在取苗效率和成功率之间存在矛盾,二者难以兼顾。因此,研究并设计出高效率和成功率的取苗机构对蔬菜钵苗全自动机械移栽具有重要意义。为解决该问题,本文研究并设计了一种顶出辅助探入式蔬菜钵苗取苗机构。该设计将探入取钵式取苗机构和顶出机构相结合,其中取苗机构通过非圆齿轮行星轮系驱动末端执行器形成特定轨迹,完成取苗作业。在取苗针夹住土钵离开钵盘的过程中,顶出机构通过顶杆顶击钵苗底部,实现辅助取苗。该机构有效缩短了钵苗脱盘时间,减少了取苗针对土钵的损伤,并解决了在高速取苗作业时取苗针无法带出土钵的问题,实现了提高取苗效率和成功率的目的。本文主要研究内容和结论如下:(1)研究了国内外蔬菜钵苗移栽技术的发展现状,分析了探入取钵式取苗机构在蔬菜移栽领域的优势以及存在的问题。结合农艺要求,提出了顶出辅助探入式蔬菜钵苗取苗机构的设计方案,并确定了本文研究的主要内容和技术路线。(2)顶出辅助探入式蔬菜钵苗取苗机构采用探入取钵式取苗和辅助顶出相结合的工作方式。研究并分析了该机构的工作原理,构建了机构的运动学模型,推导出机构各关键部件的位移及转角坐标方程,为后续设计提供理论支撑。(3)确立了探入取钵式取苗机构的设计目标,建立了设计目标与结构参数之间的函数关系模型,基于Visual Basic软件开发了可视化设计软件。通过对输入参数的调节,调整探入取钵式取苗机构的运动姿态和轨迹,得到了一组符合设计目标的结构参数和理论轨迹。(4)依据可视化设计软件得到的结构参数,利用Auto CAD软件完成了机构的结构设计,并通过NX软件建立了机构各零部件的三维模型。完成了虚拟样机的装配和干涉检查,确保了机构设计的正确性。将虚拟样机导入Adams仿真软件中,根据机构的运动原理完成虚拟运动仿真分析。通过对比仿真结果与理论分析结果,验证了机构设计的合理性,为后续样机制造奠定了基础。(5)完成了试验样机的制造,并利用摄影技术提取出样机的实际运动轨迹,验证了实际轨迹与仿真轨迹的一致性。结合台架试验,测试了样机的取苗效率和成功率。试验结果表明:机构的取苗速度为80株/min时,取苗成功率为97.22%,充分验证了顶出辅助探入式蔬菜钵苗取苗机构设计的正确性与可行性。更多还原

【Abstract】 China is the largest country in the world in terms of vegetable planting area and production output,with more than 60%of vegetable planting using the seedling transplanting method.With the development of the vegetable industry,the development and innovation of fully automated transplanting machinery has become a primary task for both domestic and international vegetable industries.Currently,the seeding pick-up mechanism for probing and picking plugs has been widely applied in the field of vegetable plug seedling transplantation.However,there is a conflict between the seedling pick-up efficiency and success rate of this mechanism.It is difficult to balance both.Therefore,researching and designing a seedling pick-up mechanism with high efficiency and high success rate is of significant importance for fully automated vegetable plug seedling transplantation.To address this issue,this thesis studied and designed an push-out assisted probing seedling pick-up mechanism for vegetable plug seedlings.This design combined the seeding pick-up mechanism for probing and picking plugs with the push-out mechanism.The seeding pick-up mechanism drove the end effector to form a specific trajectory through a non-circular gear planetary gear system,completing the seedling pick-up task.During the process of the pick-up needles gripping the plug and leaving the seedling tray,the push-out mechanism used a push rod to strike the bottom of the plug seedling,which assisted in the process of seeding pick-up.This machinery effectively shortened the time for seedling plugs leaving the tray,reduced the damage to the plug during the picking process,and significantly improved the issue of the picking needles failing to lift the plug during high-speed seedling picking operations.It achieved the goal of improving both seeding picking efficiency and success rate.The main research contents and conclusions of this thesis are as follows:(1)The development status of domestic and international vegetable seedling transplanting technologies was studied.And the advantages and problems of the seeding pick-up mechanism for probing and picking plugs in the vegetable transplanting field were analyzed.Based on agronomic requirements,the design of the push-out assisted probing seedling pick-up mechanism for vegetable plug seedlings was proposed.And the main contents and technical route of this thesis were determined.(2)The push-out assisted probing seedling pick-up mechanism for vegetable plug seedlings adopted a working method that combined seeding pick-up mechanism for probing and picking plugs with the push-out mechanism.The working principle of this mechanism was studied and analyzed.The kinematic model of the mechanism was formulated.The displacement and angular coordinate equations of each key component of the mechanism were derived,providing theoretical support for the subsequent design.(3)The design objectives of the seeding pick-up mechanism for probing and picking plugs were established.The functional relationship model between the design objectives and structural parameters was formulated.Based on Visual Basic software,a visualization design software was developed.By adjusting the input parameters,the motion posture and trajectory of the seeding pick-up mechanism for probing and picking plugs were adjusted,and a set of structural parameters and theoretical trajectories that met the design objectives were ultimately obtained.(4)Based on the structural parameters obtained from the visualization design software,the mechanism’s structural design was completed using Auto CAD software.Additionally,the three-dimensional models of the mechanism’s components were established using NX software.The virtual prototype assembly and interference check were completed to ensure the correctness of the mechanism’s design.The virtual prototype was imported into Adam simulation software,and virtual motion simulation analysis was conducted based on the mechanism’s motion principles.By comparing the simulation results with theoretical analysis results,the rationality of the mechanism’s design was verified,laying the foundation for the subsequent prototype manufacturing.(5)The experimental prototype was manufactured,and photography technology was used to extract the actual motion trajectory of the prototype.The consistency between the actual trajectory and the simulation trajectory was verified.In combination with bench tests,the seedling picking efficiency and success rate of the prototype were tested.The experimental results showed that when the seedling picking speed of the mechanism reached 80 seeding/min,the success rate of seedling retrieval was 97.22%,which fully validated the correctness and feasibility of the design of the push-out assisted probing seedling pick-up mechanism for vegetable plug seedlings.更多还原