【作者】 徐洪广；

【导师】 赵匀；

【作者基本信息】 浙江理工大学 ， 机械设计及理论， 2012， 硕士

【摘要】 水稻是我国第一大粮食作物，全国近60%的人口以稻米为主食，在我国粮食生产中具有不可替代的作用，在粮食安全问题上也是举足轻重。我国水稻种植面积常年在3000万公顷左右，占全国谷物种植总面积的30％；稻谷总产量约20000万吨，占全国粮食总产量的40％。但由于工作环境恶劣，核心工作部件机理和结构复杂，所以机械化水平低。同时，袁隆平院士提出的超级稻已占我国水稻种植的50%左右，但其分秧和种植精度要求很高，机械化种植几乎空白。因此，水稻种植机械化已成为农业机械化“瓶颈”中的“瓶颈”。水稻钵苗移栽具有分秧精度高、不伤根等优点，被水稻专家誉为增产比率最高的种植农艺，但无序抛秧影响水稻的通风透光性和边际优势，容易引发病虫害，不宜推广；而钵苗移栽的关键技术又尚未得到很好地解决。分秧机构作为水稻钵苗移栽机的核心工作部件，如果能够发明一种结构简单、工作可靠、效率高的分秧机构，这将解决水稻钵苗移栽机研制和推广的难题，为水稻钵苗种植方式的推广奠定基础。本文成功的设计了一种具有自主知识产权的新型分秧机构——旋转“探出式”水稻钵苗分秧机构，本文的主要研究内容如下：1）在对现有分秧机构的工作机理和运动特性分析的基础上，针对水稻钵苗移栽采用塑料钵盘育秧的育秧方式，指出旋转式分秧机构的核心技术是怎样实现秧针进入钵盘取秧。作者打破传统的取秧方式，提出“探出式”取秧（专利申请号：201110264626.X），并首次将变性卵形齿轮行星轮系不等速传动应用到分秧机构的设计中；设计出旋转“探出式”水稻钵苗分秧机构（专利申请号：201110264575.0）。秧针尖点形成具有“针形”凸起的“桃形”轨迹，该轨迹满足水稻钵苗移栽的作业要求；为了保证取秧的可靠性，本方案采用夹持式取秧。该分秧机构继承了非圆齿轮啮合传动平稳、结构简单、重量轻、效率高、振动小、制造成本低等优点。2）通过建立旋转“探出式”分秧机构的运动学模型，并针对分秧机构多目标多参数的优化特点，基于VB可视化开发平台，自主开发了旋转“探出式”分秧机构的辅助分析与优化软件（登记号：2011SR074561）。借助专家经验，制定优化目标，并将其量化；将用户对轨迹是否合理的主观判断转化为客观的数值比较，降低判断的难度。3）在自主开发的优化软件的基础上，针对分秧机构参数优化的特点，提出人机交互的优化方法。采用单独分析和耦合分析两种方式，进行各参数对分秧机构优化目标影响的正交实验，获得了快速优化的途径，为分秧机构的参数优化指明了方向；并根据上述方法优化得到了符合水稻钵苗移栽分秧要求的分秧机构的机构参数。4）根据高阶变性椭圆齿轮节曲线的特点，对其节曲线的封闭性和凸凹性进行验证,采用齿条刀具范成法生成齿廓。通过建立齿廓生成数学模型，借助Matlab开发了高阶变性椭圆齿轮齿廓生成软件（登记号：2011SR051232），并获得了变性卵形齿轮（二阶变性椭圆齿轮）齿廓曲线，为后期的结构设计和虚拟制造提供了齿廓曲线。5）根据优化得到的机构参数，针对分秧机构的结构实现与制造，对其进行了整体结构设计。在实现机构功能的同时，注重考虑了易损件的可靠性设计、开模加工件的拔模方向、凸轮轮廓的曲线拟合以及分秧机构设计中须要注意的几个问题；最后在AutoCAD中完成整体装配图和零件的设计。6）借助UG软件对分秧机构零部件进行虚拟制造和装配，通过中间文件导入机械系统仿真分析软件ADAMS中进行分秧机构的动态仿真。将动态仿真结果和VB优化结果进行比对，两者获得的秧针尖点运动轨迹高度一致，这相互验证了理论模型与虚拟仿真模型的正确性，同时证明了旋转“探出式”分秧机构方案的可行性。更多还原

【Abstract】 The rice is the main food crop cultivated the most in China,which is the staple food for60%of population of our country,irreplaceable in grain production,and relevant to Food Security.Theperennial cultivated area of rice is about300million hectares,accounting for30%of thecultivated area of grain;The yield of rice is about2billion tons,accounting for40.7%of foodproduction.Due to severe working environment of rice transplanter and complication of workingmechanisms and structure of its core working parts,the level of mechanization of rice productionis low.Super rice proposed by Yuan longping accounts for50%of grain cultivated area,andrequires high-accuracy planting,its mechanization production is nearly blank.So mechanizationof rice cultivation becomes of bottleneck of mechanization of farming.Rice pot seedling transplanting has the advantages of high-accuracy separating seedlings forplanting and so on,and will not harm the root,thought as agriculture cultivation with the hightestyield increasing ratio by rice expert,but transplanting rice by throwing without order influenceventilation and light of rice and marginal advantage,easily leading to plant diseases andpests,standing the way to popularize;and the key technology of pot seedling transplanting isimmature.Transplanting mechanism is Core working parts of rice transplanting machine,and toinvent a transplanting mechanism that works durably and efficiently with simple structure willsolve the problem of research and popularizing of rice pot seedling transplanting machine,to laythe foundation for popularizing rice pot seedling transplanting.In this paper, the new rotary rice transplanting mechanism with extensile claw pickingseedlings is been successful designed with independent intellectual property rights,The researchof this paper includes as followed:(1) On the basis of analysing working mechanisms and kinetic characteristic of existingtransplanting mechanism,aiming at the plastic pots rice pot seedling transplanting adopts to raiserice seedlings,this paper illustrates core technology of rotary transplanting mechanism is howseedling-picking claw accesses pot to pick seedling.Mechanism in this paper break throughtraditional method to pick seedling,proposing stretch out of seedling-picking claw(patentnumber:201110264626.X) to pick seedlings,applying epicyclic train composed by denaturedegg gears in transplanting mechanism first time(patent number:201110264575.0)；the track offront endpoint of seedling claw is like a peach shape with a sharp,which meets the demand forrice pot seedling transplanting.To ensure reliability of picking seedling,in this paper picking seedling by clipping is adopted.This transplanting mechanism has many advantages derived formnon-circular gear meshing,such as drive steady,simple structure, light weight,highefficiency,sligh vibration,low fabrication cost and so on.2) To consider the multiple-target and multiple-parameter characteristics of transplantingmechanism optimizing, the auxiliary analysis and optimization software of transplantingmechanism （software registration number：2011SR074561）has been developed on the VBvisualization development platform.At first, the Kinematic Model of transplanting mechanismmust has been built.With expert experience,the target parameters have been determined,andbecome quantificat,the subjective judgments of user on rationality of the track of this mechanismhas been transformed into comparision of objective value, lowering the difficulty of judgment.(3) Based on the of auxiliary analysis and optimization software, according to thecharacteristics of the optimization of transplanting mechanism,the optimization method ofHumanComputer Interaction has been proposed,employing Separate Analysis and CouplingAnalysis to do the Orthogonal experimental to analyse effect of each parameter on kineticcharacteristic of transplanting mechanism, obtaining the accesee to optimizing fast,pointing outthe direction for optimizing parameters of mechanism,following the optimization methodproposed,the parameters of transplanting mechanism of which the track meets the demand of ricetransplanting has been obtained.(4) According to the characteristic of pitch curve of higherorder denatured ellipse gears,thispaper tests and verifies its Closure and concavity,employing generation method adopting rack togenerate tooth profile.through building the mathematical model of tooth-profile generation,thesoftware to generate tooth profile of higherorder denatured ellipse gears has been developed onthe platform of Matlab,（software registration number:2011SR051232）,obtaining the toothprofile of denatured egg gears(second order denatured ellipse gears),giving support to thestructural design and Virtual Manufacturing at later stage.(5) According to the optimizied parameters of mechanism,aiming at structure realizing andmanufacturing of transplanting mechanism,its structure has been designed integrally.whenfunction realized,more attention is paid to reliability design of easily damaged parts, pullingdirection of casting parts, curve fitting of cam and several problems needing to be taked intoaccount in design have been expounded,and the design of each part and assembly drawing iscompleted inCAD.(6) The virtual manufacturing of each part and the virtual assembly of the transplantingmechanism has been done in three-dimensional software UG,exported to the ADAMSmechanical system simulation software for dynamic simulation of the structure.the dynamic simulation result from ADAMS has been compared with the result fromthe optimizationsoftware based on VB,two track are extremely similar, Both of the two methods were used tocross-validate the results.And the result proved the feasibility of rotary transplanting mechanismwith extensile claw picking seedlings adequately.更多还原