浅谈GPS_RTK在线路横断面测量的方法

2011年12月 第9卷第6期 地理空间信息 GEOSPATIAL INFORMATION Dec.,2011 Vol.9,No.6 浅谈 GPS-RTK在线路横断面测量的方法 杨 康 （湖北省国土测绘院，湖北 武汉 430010） 摘 要：介绍使用 GPS-RTK线路横断面测量的基本思路和操作方法，包括适用于 GPS-RTK作业的任意中桩点切线方位角 的计算和横断面线的确定，提高了横断面测量的工作效率和数据精度。 关键词：GPS-RTK；横断面测量；切线方位角 中图分类号：P258 文献标志码 : B 文章编号: 1672-4623 (2011) 06-0139-02 收稿日期：2011-09-30 线路横断面测量是线路勘测设计的一项重要内容， 是线路设计（线路及其配套设施）及确定土方工程量 的重要依据。常规横断面测量方法主要是全站仪法和 水准仪皮尺法，在实际应用中存在横断面方位和点位 偏差。通常用十字杆确定横断面方向，但在实际操作 中很难保证垂直于中心线，角度偏差产生的误差将随 着距离线型递增；在通视情况不佳且地形复杂的情况 下，作业员很难选取点位以致不能正确反映地形。GPS- RTK（载波相位动态实时差分测量）集众多优点于一 身，现在已经广泛应用于各个测量领域，且相应测量 规范 编程规范下载gsp规范下载钢格栅规范下载警徽规范下载建设厅规范下载 已经出台，使用RTK测量可以不受时间气候限制， 实时动态的获得 cm 级精度的三维坐标（一般平面 1 cm+1× 10-6，高程 2 cm+1× 10-6），在线路横断面测量 中利用RTK技术将大大提高作业效率并保证数据质量。 1 使用 GPS-RTK测量横断面思路 路线横断面测量即测定横断面方向线上各高程变 化点之间的水平距离和高差。用 RTK测量横断面首先 应确定每一个中桩点处得横断面方向线，将方向线文 件做成dxf格式通过底图方式导入手薄或采用线放样的 方法在横断面线上测出各高程变化点的三维坐标，通 过三维坐标计算出相邻点之间的水平距离和高差，最 后绘制横断面图。 2 横断面方向线的确定 2.1 曲线上任意一点切线方位角的确定 目前的路线设计中主要使用直线、圆曲线、缓和 曲线 3 种线型，线路中线是由这 3 种线型互相组合光 滑连接而成。其中直线的曲率 K=0，圆曲线的曲率 K=1/ R（R为设计半径），缓和曲线设计时遵循 RL=C (C为 常数) 原则，距起点 L处的曲率 K=1/R=L/C。 对于中线上任意曲线段，起点 A处曲率为 KA，桩 号（里程）为 LA，终点 B处曲率为 KB，桩号为 LB，则 位于 AB之间桩号为 Li的任意点曲率 Ki可由下式推导 出来： ， 则 （1） 很明显，式（1）对于直线、圆曲线、缓和曲线都 适用，但只是同一种曲线段，A, B通常是该曲线段与 其他曲线段的分界点。 图 1 曲线上任意一点切线方位角的确定 如图 1所示，在以 A点为原点，A点切线为 x轴， 与 x轴垂直且方向指向曲线内侧的坐标系中，i点切线 方位角求微分，有： （2） 则 （3） 将式（1）代入式（3）中求积分： （4） 地理空间信息140 第9卷第6期 在线路坐标系中 A 点切线方位角为 A，考虑到线 路有左偏和右偏 2种情况，则任意点 i在路线坐标系下 切线方位角为： （5） 式中，“ ”表示左偏时取“-”，右偏时取“+”，故， 若已知任意曲线起点和终点的曲率和起点方位角，则 可由弧长求出任意点的切线方位角。 2.2 横断面方向线的确定 方法一： 图 2 横断面方向线的确定 如图 2所示，根据设计坐标及任意点 P 桩号可以 求出过 P 点切线方位角 P，则横断面方向线方位角 ，其 中， , , 在线路地形图上根据实际需要确定横断面长度 d1，d2 之后则可以很据 P点坐标求出横断面线 2个端点 C, D 坐标。 同理可求得 C点坐标。由此可确定横断面方向线。 方法二：还有一种方法就是通过 CASS 里面的命 令来画出已知方位角的方向线。方位角又称地平经度 (Azimuth (angle) 缩写 Az)，是从某点的指北方向线起， 依顺时针方向到目标方向线之间的水平夹角。而 CASS 里的角度则是象限角，以水平向右为 0 °，顺时针为 负，逆时针为正。若方位角为 ，CASS 里的角度为 ， 则有 + =90°。求出了横断面中桩点切线方位角 i 之 后，其横断面方向线可以转换成在 cad里的角度。 通过命令“@直线长度< ”可画出方向线，方法 如下： ①先画直线的第一点；②然后输入：“@100<60”。 就可以画出长度为 100 m，方位角为 30°的横断面方 向线。 2.3 使用 GPS-RTK测横断面步骤 1）计算各中桩坐标，确定各中桩处横断面方位线。 通过线路设计原始数据根据上述各 公式 小学单位换算公式大全免费下载公式下载行测公式大全下载excel公式下载逻辑回归公式下载 计算各中桩及 加桩坐标和切线方位角，求出横断面方位角。 2）在设计图上绘制出各中桩位置和横断面线将数 据导入 GPS手薄。对于支持底图功能的手薄来说，可 以将中桩位置和横断面线绘制成 CAD图，保存呈底图 所需格式（如 .dxf等），在实地调出底图则可以沿设计 好的横断面线在各高程特征点测定三维坐标。 ①制作方向线 dxf文件。按步骤 2）里的方法画出 横断面方向线，保存为 autocad2000 /LT2000 dxf格式。② 将 GPS手簿（以中海达 V8手簿为例）连接上电脑，进 入测量模式，点击“底图”，选择 dxf 文件所在路径， 将文件导入手簿。 3）求定测区转换参数。搜集测区分布均匀控制点 的线路坐标和对应的 WGS-84 坐标，输入手簿求出转 换参数。 4）野外实测。选择离所测部分较近、视野开阔的 已知点上架设基站，基站实时发送坐标改正数据至移 动站，此时移动站接受基站数据可实时解算获得点三 维坐标。在测断面之前应先到另一已知点上，通过比 较已知点坐标和移动站所测坐标来验证转换参数正确 性以及基站架设的精度，确定误差在允许范围内（实 测坐标与已知坐标 XYZ 均在 2 cm 内）则可以开始按 步骤 2）测量。 5）数据处理。将野外测量数据导出 .dat格式，使 用南方 CASS 等软件进行横断面图的绘制。绘制完成 后应对断面图检查，查看有无飞点，与实际地形是否 一致等。 3 结 语 综上所述，使用 RTK测量横断面不受天气及通视 条件影响，减少了测量的工作量，有效提高了作业效 率，测量精度也得到提升，但在一些树林、高建筑物 下面等移动站接收不到差分信号的地方需配合全站仪 进行补测。 参考文献 [1] 李柏林.道路坐标测量技术［M］.重庆：重庆大学出版社，2007 [2] 徐绍铨，张华海，杨志强，等. GPS测量原理及应用［M］.武 汉：武汉大学出版社，2003 [3] 袁安存. 全球定位系统(GPS)原理与应用［M］.大连：大连海 事大学出版社，1999 [4] 唐杰军，赵欣.道路工程测量［M］.北京：人民交通出版社，2010 [5] 李全信.线路中线坐标计算的通用数学模型［J］.勘察科学技 术，2001（3）：43-47 [6] 刘伯莹，姚祖康 .公路设计工程师手册［M］.北京：人民交通 出版社，2005 [7] GB/T18314-2009.全球定位系统(GPS)测量规范［S］. 作者简介：杨康，助理工程师，主要从事工程测绘工作。 地理空间信息6 第9卷第6期Index(Vol.9,No.6)GEOSPATIAL INFORMATIONⅥ deformation in the application, which first introduced the definition of regression model, and then described the multiple regression equa- tions, the regression equation was significant and the regression coef- ficient was significant, the last light of the specific examples of the re- gression equation analysis, modeling, and forecast charts to show the true value of the curve, as well as the remnant of the margin curve on regression analysis model of the actual value. Key words regession analysis , deformation monitor, model （Page:136） Method of GPS-RTK Technique to Route Cross-section Survey by YANG Kang Abstract The paper introduced the basic ideas and operation method of measuring route cross-scetion with GPS-RTK, including how to fig- ure out tangent azimuth angle of random central stake points and cross-sectional line in the work with GPS-RTK. It would improve the ef- ficiency and data accuracy in the cross-section survey. Key words GPS-RTK technique，cross-section survey，tangent azi- muth angle （Page:139） Research on Short-distance Precise Trigonometric Leveling Instead of Second-class Leveling by Han Junsheng Abstract The traditional geometrical leveling is inconvenient in fluctu- ating area .This article discussed the viability of monitoring the vertical displacement in small area, using the common Total Station instead of second-class leveling. Base on the formula of precise trigonometric leveling, it discussed the error resources and accuracy in Short-dis- tance. Observed data were acquired by the common Total Station, and then verified the reliability of this method. At last it also gave out sev- eral precise measures, strengths and weaknesses. Key words Total Station，trigonometric leveling，short-distance，sec- ond-class leveling，precise leveling （Page:141） Transformation of Coordinate Axis between ITRF2008 and CGCS2000 by MIAO Long Abstract Based ITRF2008 reference frame on ITRF frame coordinate which is related to present precise ephemeris，and the achievement of CGCS2000 coordinate axis which is required in the basic mapping pro- ducing project about scale of one to a ten thousand, the thesis mainly discussed the conversion method of frame from ITRF2008 to CGCS2000 and the precision analysis after conversion. It also mainly analysed some key problems about transformation. Key words ITRF2008，CGCS2000，frame conversion，epoch con- version，speed field （Page:144） Research and Practice for the Independent Experimental Course of Re- mote Sensing by XU Yongming Abstract This paper analyzed the defects of traditional teaching mode which used in remote sensing experimental courses and the necessity of establishing independent experimental courses. Teaching reform and practice were carried out in the independent experimental course of Comprehensive Practice of Using Remote Sensing Software. The teaching reform of the course content, teaching method, teaching ma- terial and assessment model were clearly discussed, and the compre- hensiveness characteristic of the course was highlighted. Practices show that the teaching mode of this independent experimental course can effectively promote students' technology level and application ca- pability, and improve the teaching quality. Key words Remote Sensing，Comprehensive Practice，independent course，teaching practice （Page:146） Application of Project Study to Teaching of Remote Sensing Major Courses by SUN Deyong Abstract This paper takes ocean remote sensing as an example, and shows the application of project study in remote sensing major cour- ses. Teaching practice results demonstrate that this method can obtain good teaching effect. Students' learning interest can be stimulated, and their capability in problem analysis and solving can be greatly im- proved. Key words Project study; Remote sensing major courses; Teaching design; Practical ability （Page:148） Analysis of the Progress of Compelling《Atla of Republic of China Province District Border》's Examination and Receive by CHEN Zhongyuan Abstract This article introduced the progress of comparing《Datailed Atlas》's necessary and principle, examing and receieving the result of the work. Beside that, it also give us the details of main idea and im- plementation plan. Key words 《Datailed Atlas》, examing, receieving （Page:150） Research on Several Issues of Map Annotation Design by HE Lihua Abstract Map is marked by Annotation for identifying object. The choice of the font style and size is an important part of map design. The paper described the importance of Annotation on the map, and intro- duced the design of the font style, size and color etc. And the general design principles and the transform between several kinds of annota- tion sizes were summarized further. Finally, it investigated several fac- tors which had impact on the color design of annotations. Key words map, Annotation, design （Page:153） Data Conversion from MapGIS to ArcGIS Using FME by ZHENG Shike Abstract Through the analysis of data formats of MapGIS and ArcGIS and the discussion of traditional methods of data conversion, the paper proposed the technical route of using FME to achieve the transition from MapGIS data to ArcGIS data.Comparative analysed the differen- ces of point,line,surface elements in target data and source data.A lot of practice shows that by converting into Geodatabase (MDB) is the best way to achieve the transition from MapGIS data format to ArcGIS data format. Key words FME；MapGIS；ArcGIS；Data conversion （Page:155） Electronic Tachometer Eccentric Lofting New Method for Measuring and its Reliability by WU Wei Abstract Currently in engineering surveying, electronic tachometer has been widely used, based on electronic tachometer lofting applica- tions in engineering requirements for lofting points with measurement site must pass visual, however, in the actual work of these two points are often impassability visual. Therefore, this paper presents a new electronic tachometer lofting method, and a detailed discussion on the lofting principle, accuracy and reliability. At the same time, this paper based on the Datang crown close mountain GongSiJi units on the big power limited pressure small project main workshop of pile foundation A standard engineering projects, demonstrates the method of lofting results within and outside precision. It has been found that, this paper expounds the lofting method in different accuracy requirements engin- eering is feasible and reliable. Key words eccentric lofting; precision estimation; error analysis; mean square error of a point （Page:158）