测量学双语课件

1、Chap.4 Distance surveying and line orientation Highway school Changan universityChap.4 Distance surveying and Chap.4 Distance surveying and line orientationDistance: refers to length of the curve line between two projections of two points to the geoid along the plumb line.Main contents: 钢尺量距（steel t

2、ape distance surveying）； 视距测量（stadia surveying ）；光电测距（photoelectric surveying distance）卫星测距（Satellite ranging）；直线定向（line orientation）；1Chap.4 Distance surveying and Key content:坐标方位角（ coordinates azimuth calculation ）Classification: Direct measurement method - steel tape distance surveying;Optical m

3、easurement method - stadia distance surveying； Physical measurement method - photoelectric surveying distance; Key content:坐标方位角（ coordinates4-1 Steel tape distance surveying一、The tools 钢尺（Steel tape）, 标杆（benchmarking）, 测钎（measuring brazing） and 垂球（Metal ball ball）. 1. Steel tape Feet long ： 20 mete

4、rs, 30 meters, 50 meters； Specifications: plastic coated or not plastic coated. Scale and note: mm, cm, dm,m 刻线尺（compartmentalized rule） 端点尺（endpoint rule） Endpoint rule Compartmentalized rule 14-1 Steel tape distance surve4-1 Steel tape distance surveying一、The tools2. Flower stem: Fixed line forwar

5、d direction line 3. Measuring brazing: fix rule segment endpoint position. 二、直线定线（Fixing line）目测定线和经纬仪定线14-1 Steel tape distance surve4-1 Steel tape distance surveying三、 Steel tape distance surveyingThe basic requirements: “straight, level, accurate. 1. The distance surveying at flat ground Use the

6、equation: D=nl+q l - the the length of whole feet; n - the whole rule section number, q - zero rule section length. surveying error: D = D往-D返Distance average: D平= （D往-D返）The relative error: 14-1 Steel tape distance surve4-1 Steel tape distance surveying2. The distance surveying at the tilt ground(1

7、) flat surveying method: (2) inclined surveying method 14-1 Steel tape distance surve4-2 Stadia surveying Stadia surveying is indirect ranging method 它利用望远镜内十字丝分划板上的视距丝及刻有厘米分划的视距标尺(地形塔尺或普通水准尺)，根据光学原理可以同时测定两点间的水平距离和高差. The relative error is about 1/300, below the rule surveying distance, Determine th

8、e elevation precision is below level survey, Stadia measurement is widely used for measuring the details topography Measurement.14-2 Stadia surveying Stadia 4-2 Stadia surveying 一、Stadia formula when sight is horizontaln14-2 Stadia surveying 一、Stadi4-2 Stadia surveying 一、Stadia formula when sight is

9、 horizontalHorizontal distance formula: Height difference formula:nl14-2 Stadia surveying 一、Stadi4-2 Stadia surveying二、The stadia formula when sight is tiltingHorizontal distance D :Elementary height difference:The height difference between A and B:14-2 Stadia surveying二、The st4-2 Stadia surveying三、

10、 The steps of the stadia surveying1在测站上安置经纬仪，量取仪器高（桩顶至仪器横轴中心的距离），精确到cm；2瞄准竖直于测点上的标尺，并读取中丝读数值；3用上、下视距丝在标尺上读数，将两数相减得视距间隔；4使竖盘水准管气泡居中，读取竖盘读数，求出竖直角;5.根据视距公式，计算水平距离和高差及立尺点的高程。14-2 Stadia surveying三、 The s4-2 Stadia surveying四、Stadia measurement errors1. The stadia rule partition error 2. Constant K value

11、 error 3. Vertical Angle measurement errors 4. Stadia cross reading error 5. Influence of stadia rule tilting to stadia measurement 6. The influence of external meteorological conditions to stadia measurement (1) the influence of atmospheric refraction (2) the influence of atmospheric turbulence14-2

12、 Stadia surveying四、Stadia4-3 Electromagnetic rangefinder一、Ectromagnetic ranging overview 1. Principle To record the electromagnetic wave traveling time between two endpoints round-trip once time, using its propagation velocity in the atmosphere to calculate the distance between two points. 14-3 Elec

13、tromagnetic rangefind4-3 Electromagnetic rangefinder一、Ectromagnetic ranging overview 2. Rangefinder classification （1）carrier wave adapted Microwave rangefinder Photoelectric rangefinder 1.Laser rangefinder 2.Infrared rangefinder （2） method to calculate time Phase type rangefinder Pulsed rangefinder

14、 14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder (3) according to distance Remote range: tens of kilometers Medium-range : from several kilometers to 10 kilometers Short-range: below three kilometers(4) by carrier number Single carrier: visible light, Infrared light, microwave. Double

15、carrier: visible + visible light, Visible + infrared radiation Three carrier: visible + visible + microwave, Visible + infrared + microwave etc.14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder (5) By the reflection target Diffuse target (no cooperation target) Cooperation goal-flat mirr

16、or, prism Active reflector-same frequency carrier wave transponder； different frequency carrier transponder, etc 14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder二、Pulse photoelectric surveying distance 14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder三、Phase photoelectric ra

17、ngefinder 1.Basic principle14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder三、Phase photoelectric rangefinder 2Basic formula Modulation wave modulation frequency f, angular frequency t, period T,14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder三、Phase photoelectric rangefinde

18、r 2Basic formula Set modulated signal is sine signal, including the euploid of 2,2 N2, and terminal part less than 2, namely: 14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder三、Phase photoelectric rangefinder3The determination of N value14-3 Electromagnetic rangefind4-3 Electromagnetic r

19、angefinder三、Phase photoelectric rangefinder4The inner light path set 14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder四、Total reflecting prisms 由于光在玻璃中的折射率为1.51.6，而光在空气中的折射率近似等于1，也就是说光在玻璃中的传播要比空气中慢，因此光在棱镜中传播所用的超量时间会使所测距离增大某一数值，称为棱镜常数。 14-3 Electromagnetic rangefind4-3 Electromagnetic ran

20、gefinder五、Distance measurement steps 测距时，将测距仪和反射镜分别安置在测线的两端，仔细地对中。接通测距仪的电源，然后照准反射镜，检查经反射镜反射回的光强信号。合乎要求后即可开始测距。六、Distance measurement data process1Add constants correct14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder六、Distance measurement data process2Multiply constant corrections 3Meteo

21、rological correct 不同型号的测距仪，气象改正公式的系数也不同，在仪器使用说明书内给出了气象改正计算公式。4.Tilt correction 5To calculate to geoid corrections14-3 Electromagnetic rangefind4-3 Electromagnetic rangefinder七、Error sources of photoelectric rangingDistance error can be divided into two parts: The first part error of it is proportion

22、al to distance D, namely the speed of light value error, atmospheric refraction error and ranging frequency error; Another part is irrelevant with distance, namely phase error, to add constant error, plummet error, Generally rangefinder precision expression14-3 Electromagnetic rangefind14-4 Electrom

23、agnetic wave rangefinder inspection 一、OverviewInspection items mainly include: 1 function examines, 2 The correctness of calibration of three axis relationship 3 luminescence tubes phase uniformity (beadle error) measurement, 4 Amplitude phase error measurement, 5 period errors measurement, 6 determ

24、ination of add constants 7 by constant (including crystal frequency), 8 internal and external precision of the examination. 9 adaptive performance testing:10 measurement process detection 14-4 Electromagnetic wave ran4-4 Electromagnetic wave rangefinder inspection 一、OverviewInspection items mainly i

25、nclude: 功能检视;三轴关系正确性的检校;发光管相位均匀性（照准误差）的测定；幅相误差的测定；周期误差的测定；加常数的测定；乘常数（包括晶振频率）的测定；内部、外部符合精度的检验；适应性能的检测：测程的检测。14-4 Electromagnetic wave rang4-4 Electromagnetic wave rangefinder inspection二、The determination of the period errors1. What is the period errors Cycle repeated error according to certain dista

26、nce, mainly comes from internal fixed crosstalk signal. 14-4 Electromagnetic wave rang4-4 Electromagnetic wave rangefinder inspection二、The determination of the period errors 2The measurement method of the period errors 14-4 Electromagnetic wave rang4-4 Electromagnetic wave rangefinder inspection三、Th

27、e determination of surveying distance constant1. Simple measurement of add constant2.Fix add, by constant by 6 sections comparison. To get the observation value by comparison method ,to compare observation with the known baseline data to obtain constant K, by constant R. 14-4 Electromagnetic wave ra

28、ng4-5 Line orientationDetermine the horizontal angle between a straight line and a basic direction. 一、Basic direction1True north direction :过地面某点真子午线的切线北端所指示的方向。采用天文测量的方法测定。2Magnetic north direction ：磁针自由静止时其指北端所指的方向，称为磁北方向，可用罗盘仪测定。 3Coordinates north direction ：过O点的真子午线坐标纵轴（X轴）正向所指示的方向，称为坐标北方向。实用上常

29、取与高斯平面直角坐标系中X坐标轴平行的方向为坐标北方向。14-5 Line orientationDetermine4-5 Line orientation二、方位角（Azimuth ） An azimuth is the direction of a line as given by an angle measured clockwise from the north end of a meridian. It ranges in magnitude from 0360。1True azimuth (A): the direction of a line as given by an ang

30、le measured clockwise from the true north。2. Magnetic azimuth(Am)：the direction of a line as given by an angle measured clockwise from the magnetic north。3Grid azimuth()：the direction of a line as given by an angle measured clockwise from the Grid north。14-5 Line orientation二、方位角（Azi4-5 Line orienta

31、tion三、磁偏角（Magnetic declination） 子午线收敛角（meridian convergence）1Magnetic declination: The horizontal angle between the north of the compass and true north 。2meridian convergence： The horizontal angle between true and grid north。 and are positive when themagnetic north or grid north is in the east to true north, the otherwise are negative.过O点的真子午线14-5 Line orientation三、磁偏角（Mag4-5 Line orientation四、The relationship between three azimuths14-5 Line orientation四、The rel4-5 Line orientation五、Pros and cons grid azimuth 14-5 Line