大学毕业论文—工程测量学.doc

工程测量学毕业论文 题目：数字测图技术 目 录 绪 论······································································3 一. 数字测图原理与方法··················································4 二.任务实施····················································4 1.已有资料利用与分析················································4 2.主要精度指标··························································4 3.平面控制测量··························································4 3.1野外实地堪踏选点·················································4 3.2导线数据观测························································4 3.3控制网数据处理····················································4 4.高程控制测量······························································4 4.1仪器设备及施测方法·············································4 4.2四等水准测量技术要求··········································4 5.碎步测量采集数据···················································4 6.内业数字化成图······················································4 6.1成图软件选择及应用·············································4 6.2内业成图······························································4 7.上交成果·································································4 结束语 致谢 绪 论 数字测图(Digital Surveying and Mapping，DSM)系统是以计算机及其软件为核心在外接输入输出设备的支持下，对地形空间数据进行采集、输入、成图、绘图、输出、管理的测绘系统数字地图(Digital Map)以数字形式存贮在磁盘、磁带、光盘等介质上的地图。主要作业过程三个步骤：数据采集、数据处理及地形图的数据输出（打印图纸、提供软盘等）随着电子全站仪及电子计算机的普及，地形图的成图方法正在逐步地由传统的白纸法成图向数字测图方向发展。特别是在我国的东部沿海发达地区，数字测图几乎已占据了大部分的地形图测绘市场。数字化测图以其成图精度高、成图周期短、即用即测快速建立城市大比例尺基础地理信息数据库点，已被一些城市建设规划管理的领导所青睐和引用全数字GIS提供空间数据。 数字测图原理与方法 一、比例尺的概念及比例尺的分类 比例尺：图上长度与相应的实地水平长度之比，称为该图的比例尺。 比例尺的分类 ①小比例尺：1:25万、1:50万、1:100万 ②中比例尺：1:2.5万、1:5万、1:10万 ③大比例尺：1:500、1:1000、1:2000、1:5000、1:1万 二、白纸测图与数字测图的基本概念 (1)白纸测图：传统的地形测量是利用测量仪器对地球表面局部区域内的各种地物、地貌（总称地形）的空间位置和几何形状进行测定，以一定的比例尺并按图式符号绘制在图纸上，即通常所称的白纸测图。 (2)数字测图：广义地讲，生产数字地图的方法和过程就是数字测图。数字测图实质上是一种全解析机助测图方法。它以计算机为核心，在相关输入输出设备的支持下，对地形空间数据进行采集、存贮、处理、输出和管理。 三、大比例尺数字地图定义 贮存在数据载体(磁带、磁盘或光盘)上的数字形式的大比例尺地图。 四、大比例尺数字地图的特点 （1）大比例尺数字地图以数