水稻钵苗宽窄行移栽机构特殊“8”字形轨迹、姿态形成机理研究与参数优化

Taking into account the advantages of anti-lodging, anti-disease and significant yield stimulation of potted-seedling wide-narrow row transplanting, and the lack of this kind of working machine, this project aims at developing spatial high-order non-uniform speed planetary gear trains, trajectory shape and attitude synthesis based on the research results of the existing potted-seedling transplanting mechanism and carpet seedling transplanting mechanism. The rice potted-seedling wide-narrow row transplanting mechanism with special "8" shape trajectory is proposed and studied.1）Explore high-order planetary gear trains which have potential capability to realize special "8" shape trajectory for potted-seedling transplanting. Analyze their transmission characteristics, and describe the ideal transplanting trajectory, build the calculation model based on the given trajectory of the mechanism. 2) Establish multi-objective optimization model of the potted-seedling wide-narrow row transplanting mechanism with planetary gear trains. Propose and study the parameters guide multi-objective optimization method which can control the optimization process to achieve the optimization of the mechanism attitude and scale, build the dynamic model to complete dynamics balance optimization. 3) The kinematic and dynamic characteristic is tested to verify and correct the theoretical model. Finally, the design theory and method of potted-seedling wide-narrow row transplanting mechanism are established to provide a theoretical foundation for the development of new potted-seedling wide-narrow row transplanter, which have an urgent practical significance to promote the sustainable development of rice potted-seedling transplanter industry.

水稻钵苗宽窄行移栽具有抗倒伏、防病害、增产显著的优点，而国内缺乏相应作业机械。本项目拟以现有钵苗移栽机构和毯苗移栽机构的研究成果为基础，开展空间高阶非匀速行星轮系机构构型、轨迹形状和姿态综合，提出并研究具有特殊 "8" 字形移栽轨迹的钵苗宽窄行移栽机构。1）探索具有特殊"8" 字形移栽轨迹实现潜力的高阶行星轮系组合形式，研究其传动特性，描述其理想移栽轨迹，建立基于理想轨迹的机构求解模型；2）建立钵苗宽窄行行星轮系移栽机构的多目标优化模型，提出并研究优化过程可控式的参数引导多目标优化方法，实现机构姿态和尺度优化，建立动力学模型完成动平衡优化；3）测试机构运动学、动力学特性并进行移栽模拟试验，验证或修正理论模型。最终，建立这种特殊"8"字形移栽轨迹钵苗宽窄行移栽机构的设计理论与方法，为钵苗宽窄行移栽机的研制奠定理论基础，对促进我国水稻钵苗移栽机行业的可持续发展具有迫切的现实意义。

水稻钵苗宽窄行移栽具有抗倒伏、防病害、增产显著的优点，而国内缺乏相应作业机械。本项目以行星轮系钵苗宽窄行移栽机构为研究对象，围绕空间行星轮系移栽机构的机构综合、轨迹再现、传动比求解、参数和姿态优化等关键问题，展开研究。.1）移栽轨迹的描述方法和基于轨迹的机构参数求解模型研究，研究了一般性空间轨迹的开链2R机构及其转轴位姿求解模型、考虑非圆齿轮节曲线凸性的2R机构输入杆旋转中心位置可行域、合理机构参数初值求解。.2）空间非匀速行星轮系机构工作原理研究和机构综合，依据钵苗宽窄行移栽的农艺要求，研究并获得了适合于空间轮系机构的空间钵苗移栽轨迹，开展了输入输出为空间交错轴的行星轮系式移栽机构构型综合研究，提出了多种水稻钵苗宽窄行移栽机构。.3）空间非匀速行星轮系水稻钵苗宽窄行移栽机构的多目标参数优化模型和求解方法，针对提出的非圆锥齿轮—交错齿轮组合传动的钵苗宽窄行移栽机构，分析机构夹、拔苗和推苗过程的工作轨迹、姿态与取苗成功率、伤苗率和立苗率之间内在联系，建立参数优化模型，编写优化软件，实现了移栽机构的多目标优化。.4）宽窄行移栽机构动力学建模与分析，分析移栽机构各构件受力情况，编写计算程序分析了机构关键位置的受力情况；测试移栽机构支座受力，验证了动力学模型具有一定的可靠性和有效性。.5）宽窄行移栽机构快速设计方法研究，将Matlab与NX结合，进行了移栽机构变形设计研究，通过修改参数即可实现移栽机构的变形，达到机构的快速设计。.6）宽窄行移栽机构样机试验，研制试验台架，利用环形土槽开展了移栽机构的无苗和带苗试验；研制了钵苗宽窄行移栽机，进行了田间试验。田间测量宽窄行距、栽苗深度、漏栽、倒苗率都符合国家标准。.本项目研究成果为开发钵苗宽窄行移栽机、提升我国移栽机行业提供技术支撑；提出的设计和优化方法具有普遍意义，可为蔬菜、果苗移栽机构、打结机构等复杂机构的多目标优化提供方法。