发布时间 : 星期五 文章机械臂设计毕设计说明书更新完毕开始阅读32109976bb68a98270fefa6c
目 录
1 绪论 ························································································································ 1 1.1 前言 ······················································································································· 1 1.2 课题的来源与背景 ······························································································ 1 1.3 研究的目的和意义 ······························································································ 2 1.4 林业集材机的概述 ······························································································ 3 1.5 国内外研究现状及发展趋势 ············································································· 3 1.5.1 国内发展动态及研究现状 ············································································· 3 1.5.2 国外发展动态及研究现状 ············································································· 4 1.6 论文主要研究内容 ······························································································ 5 2 机械臂设计理论 ···································································································· 7 2.1 机械臂的组成及分类 ························································································· 7 2.1.1 机械臂的组成 ·································································································· 7 2.1.2 机械臂的分类 ·································································································· 7 2.2 机械臂的自由度及坐标形式 ············································································· 8 2.2.1 机械臂的自由度 ····························································································· 8 2.2.2 机械臂的坐标形式 ························································································· 8 3 集材机机械臂的总体设计 ················································································· 10 3.1 机械臂的设计参数 ···························································································· 10 3.2 机械臂的结构形式 ···························································································· 10 3.3 机械臂典型部件特点 ······················································································· 10 3.4 机械臂的工作范围 ···························································································· 11 4 集材机工作装置的受力分析 ············································································· 13 4.1 集材机机械臂的工况分析 ··············································································· 13 4.2 集材机机械臂的受力分析 ··············································································· 13 4.2.1 空载时各级臂架所受的弯矩 ······································································· 13 4.2.2 抓举活立木时各级臂架所受弯矩 ······························································ 14 4.3 机械臂连接处的受力分析 ··············································································· 15 4.3.1 主臂铰接处分析 ··························································································· 15 4.3.2 副臂铰接处分析 ··························································································· 15 5 基于SOLIDWORKS集材机机械臂的造型 ···················································· 17 5.1 参数化设计与SOLIDWORKS软件 ··································································· 17 5.1.1 参数化设计 ···································································································· 17
5.1.2 SolidWorks软件介绍 ··················································································· 17 5.2 集材机机械臂零部件造型 ··············································································· 18 5.2.1 旋转基座的造型 ··························································································· 18 5.2.2 其它零部件的造型 ······················································································· 21 5.3 集材机机械臂的虚拟装配 ··············································································· 22 6 集材机机械臂的有限元分析 ············································································· 24 6.1 SOLIDWORKS有限元分析模块及理论基础 ··················································· 24 6.1.1 有限元法理论基础 ······················································································· 24 6.1.2 SolidWorks的Simulation模块 ··································································· 24 6.2 机械臂零部件的有限元分析 ··········································································· 25 6.2.1 有限元分析过程 ··························································································· 25 6.2.2 主臂的有限元分析结果 ··············································································· 26 6.2.3 副臂的有限元分析结果 ··············································································· 28 6.2.4 主臂结构优化 ································································································ 29 6.2.5 副臂结构优化 ································································································ 31 结论 ····························································································································· 34 致谢 ····························································································································· 35 参考文献 ···················································································································· 36
中南林业科技大学本科毕业设计 基于Solidworks集材机机械臂的设计
1 绪论
1.1 前言
新中国成立以来，我们国家林业建设取得了巨大成就。尤其在是改革开放之后，党中央，国务院高度重视林业工作，采取了一系列政策和措施，有效地促进了林业的发展。全社会办林业，全民义务植树运动深入发展，全民搞绿化的局面正在形成。近年来，实施天然林保护工程，退更换林，荒漠化治理和其他重点项目进展顺利，部分地区的生态条件得到改进。森林，湿地和野生动物资源保护得到加强。
我国目前的生态状况整体恶化的趋势，还没有得到根本的扭转，土地沙化，湿地，生物多样性的破坏仍然呈加剧趋势。滥伐森林，乱过度占用林地，过度狩猎野生动物，无序开采，滥挖野生植物和其他现象屡禁不止，森林火灾和病虫害对林业仍然是非常严重的威胁。林业经营和管理体制不适应形势发展的需要。林业产业规模小、科技含量低、结构不合理、木材供需矛盾突出，林业职工和森林地区的人民的收入增长比较缓慢。总体上，我国森林资源不足，森林生态系统的整体功能仍然非常脆弱。所以现在林业要面临比以往的任何时候都要更重的改革和发展的任务。
在加快推进社会主义现代化全面建设小康社会的过程中，必须把林业建设放在更加突出的位置，我们必须高度重视并加强林业方面的工作，促使我国林业能有一个比较大的发展。在西部的发展中，我们要给予林业以基础地位；在可持续发展战略的实施过程中，我们需要给林业以重要地位；在林业生态建设中，我们要给予林业以领先地位。
1.2 课题的来源与背景
第七次全国森林资源清查结果表明，截至2008年，全国森林面积为19545.22万公顷，森林覆盖率20.36%，活立木蓄积量149.13亿立方米，森林蓄积量137.21亿立方米，人工林保存面积6168.84万公顷，人工林蓄积量19.61亿立方米，种植面积居世界第一。在第六次和第七次清查间隔的五年时间内，人工林面积快速增长，人工林面积净增843.11万公顷，人工林蓄积净增4.47亿立方米，幼林地面积1046.18万公顷，森林蓄积量大大增加，森林采伐逐步向人工林转移，林木
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中南林业科技大学本科毕业设计 基于Solidworks集材机机械臂的设计
蓄积年净生长量5.72亿立方米，年采伐消耗量3.79亿立方米，森林蓄积增长继续超过消耗，长消盈余进一步扩大，天然林采伐量减少，人工林采伐量增加，人工林采伐量占森林采伐量39.44%，提高12.27个百分点，现有人工林是一种速生丰产林的发展。近年来，速丰林建设充分依靠政府推动、市场导向、利益的驱动和企业带动等运作机制，大力推进速丰林基地建设。进入成熟林(采伐年龄段)面积成倍增长，依靠传统的人工抚育和采伐技术已经不能满足现代林业生产的需要。但是传统营林生产使用的轻型油锯、割灌机、手提式挖坑机、剪草机等便携式林业机械，不仅效率低，而且均由操作者直接手持或背负进行作业，操作者除了完成控制、操作等任务外，还必须承受在作业过程中机器产生的振动和噪声，导致操作者的身体功能一定程度上受到功能性障碍或不同程度的损伤。因此，对我国现有的大型商业人工林的抚育、采伐、造材等作业机械化、高效化以成为一个核心焦点，
未来的林业生产要由劳动力集约型向技术集约型转变，以增加单位劳动生产效率，增加林区人民的收入，这也是三农问题解决的一个方面。此外，人工林的抚育是季节性的，应急性的，要在最好的季节完成除草、修剪、细化和紧急控制害虫及运输，必须通过机械化作业来提高作业效率，对于大中径材的整枝抚育作业和抚育间伐材的搬运，只靠人工的话是没有办法做到高质、高效地完成有关作业的，需要用机械化装备来达到安全高效地作业。国家中长期科学和技术发展规划纲要和林业科学技术十一五发展规划也分别将开发现代农业(包括林业)装备技术列为我国近期林业科技重点发展目标之一。
1.3 研究的目的和意义
林业装备技术水平的高低，是衡量现代林业和林业产业发展水平的重要标志，只有现代化的机械操作，才能真正解放劳动生产力，降低劳动强度，降低生产成本，提高经济效益，。近年来由于林区的劳动成本的上升，对传统劳动密集型为主的林业生产造成很大的冲击，迫切需要开发新技术、新工艺、新装备，提高自主创新能力，提高机械化和智能化的林业装备水平，改善操作环境，以高效低耗林业生产系列装备来改变传统人力为主的落后生产模式。
目前国内现有的采育作业装备的运行现状均存在功能单一的缺点，这样在采育作业过程中，林业工人就要使用多种机械设备，降低了作业效率，多种机械设
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