机械5

蔬菜钵体苗自动移栽机——取苗装置设计 摘要 移栽是蔬菜生产过程中的重要环节之一，移栽具有对气候的补偿作用和使作物生育提早的综合效益，可以充分利用光热资源，其经济效益和社会效益均非常可观。目前，国内正在应用的移栽机械多为半自动移植机，半自动移栽机靠手工送苗，效率低，劳动强度大，而国内自动移栽机的研究刚刚起步，自动移栽机从取苗到植苗都由机械自动完成，效率高。国外虽有一些自动移栽机应用于生产，但还处于不断研究与推广阶段。而取苗机构是制约自动移栽机发展的“瓶颈”，也是制约蔬菜大规模种植的关键问题之一。因此设计一种新型的取苗机构替代手工取苗，已成为我国蔬菜种植业发展的迫切需要。 本文总结吸收了国内外各种取苗机构的优缺点，在实验室已有研究成果的基础上，设计了一种新型蔬菜钵苗取苗机构，该机构可以单独作为取苗机构，实现自动取苗；或通过改进部分结构参数，可以集栽取功能于一体，即取苗和栽植苗动作都由该套机构完成。该蔬菜钵苗取苗机构结构简单，工作可靠，取苗效率高。本文主要的研究内容如下： 1.根据蔬菜钵苗取苗的技术特点和农艺要求，模拟人工取苗的轨迹、动作和姿态要求，发明蔬菜钵苗取苗机构，满足机械取苗特殊的工作轨迹要求，比现有的蔬菜取苗机构工作效率高，并且工作平稳。 2.论述了该取苗机构的工作原理和结构特点，建立取苗机构的运动学模型。 3.以建立的运动学模型为基础，基于可视化开发平台VB6.0，通过其软件分析蔬菜钵苗取苗机构辅助分析与优化软件（软件登记号：2011SR030044），介绍了该软件的人机交互界面及功能，基于该软件，解决了该机构运动学多目标优化的难点。 4.根据蔬菜取苗农艺要求，提出蔬菜钵苗取苗机构参数优化的目标和优化方法，分析各参数变化对取苗机构运动特性的影响，利用自主开发软件，采用人机交互的优化方法，优化出取苗机构的结构参数，满足蔬菜钵苗取苗的工作要求。 5.按照优化得到的结构参数，进行蔬菜钵苗取苗机构的总体设计，讨论了设计中应该注意的问题，最后在ProE、CAD下完成装配图和各零件的设计。 6.建立取苗机构的三维实体模型，对其进行虚拟装配。 关键词：蔬菜钵苗；取苗机构；工作机理；参数优化；试验研究 Optimal a
nd Desig
n of Vegetable Plug Seedli
ng Pick-up Mecha
nism of Pla
netary Gear Trai
nwith Ellipse Gears a
nd I
ncomplete No
n-circular Gear Abstract Tra
nspla
nti
ng is a
n importa
nt process ofvegetable procreati
ng,which has the fu
nctio
n of compe
nsati
ngvaryi
ng climate a
nd shifti
ng the procreati
ng of pla
nts to a
n earlier time. It helps the pla
nts to use the source of light a
nd temperature sufficie
ntly,whichwill make co
nsiderable eco
nomical a
nd social be
nefits. At prese
nt, most tra
nspla
nti
ng machi
nes are semi-automatic tra
nspla
nti
ng machi
nes，they
need pick up plug seedli
ng by ma
n，which have highwork i
nte
nsity a
nd lowwork efficie
ncy,a
nd domestic research o
n automatic tra
nspla
nti
ng machi
ne is just begi
n
ni
ng. Automatic tra
nspla
nti
ng machi
ne ca
n pick up plug seedli
ng a
nd tra
nspla
nti
ng plug seedli
ng by themselves,which have lowwork i
nte
nsity a
nd highwork efficie
ncy. The overseas have automatic tra
nspla
nti
ng machi
ne be applied i
n productio
n,but the applicatio
n a
nd research o
n automatic tra
nspla
nti
ng machi
ne is developi
ng.Thus the pick up plug seedli
ng machi
ne is the key issues,which restricted the developme
nt of automatic tra
nspla
nti
ng machi
ne a
nd at same time,which is also restricted the developme
nt of the pla
nts ofvegetable. So it's a pressi
ng requireme
nt to desig
n a
new ki
nd of pick up plug seedli
ng machi
ne. This paper co
ncludes the merits a
nd demerits of several ki
nds of tra
nspla
nti
ng machi
nes from both domestic a
nd abroad. Based o
n the achieved research result, a
newvegetable plug seedli
ng pick-up mecha
nism of pla
netary gear trai
nwith ellipse gears a
nd i
ncomplete
no
n-circular gear has bee
n desig
ned. Thisvegetable plug seedli
ng pick-up ca
n be used as seedli
ng fetchi
ng mecha
nism lo
nely to realize fetchi
ng seedli
ngs automatically. Besides, if the mecha
nism parameters of this mecha
nism have bee
n optimized properly, the motio
n of fetchi
ng seedli
ngs a
nd tra
nspla
nti
ng seedli
ngs ca
n both be realized by this mecha
nism. Thisvegetable plug seedli
ng pick-up mecha
nism has simple structure a
nd reliable performa
nce. The mai
n co
nte
nt of this paper is listed as bellow: 1. Accordi
ng to the tech
nological characteristics a
nd agricultural requireme
nts, imitate the requireme
nts of trajectory, motio
n a
nd attitude of ma
nual pick up plug seedli
ng, i
nve
nt thevegetable plug seedli
ng pick-up mecha
nism,which ca
n satisfy the specialworki
ng trajectory requireme
nts of fetchi
ng a
nd pick up plug seedli
ngs automatically. This
newvegetable plug seedli
ng pick-up mecha
nism has higherworki
ng efficie
ncy, steadier tra
nsmissio
n a
nd lessvibratio
n tha
n existi
ng mecha
nism. 2. Theworki
ng pri
nciple a
nd structural features of this automaticvegetable plug seedli
ng pick-up mecha
nism has bee
n discussed a
nd the ki
nematic mathematical model of this mecha
nism has bee
n established. 3.Based o
n the established ki
nematic mathematical model a
nd Visual Basic 6.0, develop the ki
nematic aided a
nalytical a
nd optimal software of thisvegetable plug seedli
ng pick-up mecha
nism(Register Number: 2011SR030044). I
ntroduce the huma
n-computer i
nteractive i
nterface a
nd fu
nctio
ns of this software. By this software, the difficulty of optimizatio
nwith multiple ki
nematic objects of this mecha
nism ca
n be solved. 4. Accordi
ng to the agricultural requireme
nts i
n our cou
ntry, put forward the parametric optimal objects a
nd methods of thevegetable plug seedli
ng pick-up mecha
nism. A
nalyze the i
nflue
nce of parametervitiatio
n o
n ki
nematic characteristics of thisvegetable plug seedli
ng pick-up mecha
nism. Take adva
ntage of the developed software, use the optimizatio
n method of huma
n-computer i
nteractive, a
nd obtai
n the structural parameterswhich ca
n satisfy theworki
ng requireme
nts of automaticvegetable pot seedli
ng tra
nspla
nti
ng. 5. I
n accorda
ncewith the obtai
ned structural parameters, desig
n the e
nsemble of thevegetable plug seedli
ng pick-up mecha
nism; discuss the problemswhich should be
noticed i
n the process of desig
ni
ng. Fi
nally fi
nish the desig
n of parts a
nd the assembly drawi
ng basi
ng o
n ProE a
nd CAD. 6. Establish the solid model of all parts of thisvegetable plug seedli
ng pick-up mecha
nism i
n UG6.0 a
nd the
n carry out thevirtual assemble. Keywords: Vegetable plug seedli
ng; Pick-up mecha
nism; Work pri
nciple; Parameters optimizatio
n; Test study 目录 Abstract 6 第1章绪论9 1.1前言9 1.2国内外蔬菜钵苗取苗机构的发展概述11 1.2.1我国蔬菜钵苗移栽机械化发展概况11 1.2.2我国蔬菜钵苗移栽机存在的问题12 1.2.3我国蔬菜钵苗移栽机存在问题解决途径分析12 1.2.4国外蔬菜钵苗自动移栽机的发展和研究成果13 1.2.5蔬菜钵苗移栽机发展方向14 1.3国内取苗机构存在的主要问题和发展方向15 1.3.1国内取苗机构发展存在的主要问题15 1.3.2国内蔬菜取苗机构的发展方向15 1.4本文的研究目标16 1.5本文的主要工作及内容安排17 1.6本章小结17 第2章蔬菜钵苗取苗机构的运动学分析18 2.1取苗爪工作要求的实现18 2.2蔬菜钵苗取苗机械手的机构组成与工作原理19 2.3椭圆齿轮传动的运动分析21 2.3.1椭圆齿轮的啮合特性及优点21 2.3.2椭圆齿轮的角位移、角速度和传动比分析22 2.4蔬菜钵苗取苗机械手运动学模型的建立24 2.4.1运动学分析符合的说明24 2.4.2蔬菜钵苗取苗机械手位移分析25 2.4.3机械手上各点位移方程和各构件角位移方程26 2.4.4机构上各点的速度方程和各构件角速度方程28 2.4.5机械手上各点的加度方程和各构件角加速度方程29 2.5本章小结31 第3章蔬菜钵体苗自动移栽机取苗机构的参数优化32 3.1优化目标与变量32 3.2辅助分析优化软件32 3.2.1人机交互简介33 3.2.2本课题人机交互软件介绍34 3.2.3椭圆齿轮参数计算35 3.2.4取苗机构参数优化步骤35 3.2.5取苗爪尖点的速度分析36 3.3本章小结38 第4章蔬菜钵苗自动移栽机取苗机构的结构设计38 4.1蔬菜钵体自动移栽机取苗机构的整体结构设计38 4.2取苗臂机构设计40 4.3 CAD软件介绍41 4.3.1 CAD二维取苗机构零件图41 4.4 Proe软件介绍43 4.4.1三维Proe取苗机构零件图44 4.5总装配图45 4.6本章小结46 第5章总结与展望47 5.1总结47 5.2进一步的展望48 致谢49 参考文献50 附录52