《数字测图》课件-3.1.2碎部点坐标测算原理与方法认识

数字测图DigitalMappingFragmentPointCoordinateMeasurementPrincipleandMethodRecognition碎部点坐标测算原理与方法认识原理：通过输入测站点坐标、定向点坐标，通过仪器计算功能（坐标反算）计算出两个已知点所构成的直线对应的坐标方位角和距离，同时仪器安置于测站点，盘左瞄准定向点，这样仪器视线方向同直线的坐标方位角保持一致，完成全站仪定向。Principles:Inputthecoordinatesofthemeasuringstationandtheorientationpoint,calculatethecoordinatesofthedirectionanddistanceofthestraightlineformedbythetwoknownpointsthroughtheinstrumentcalculationfunction(coordinateinversecalculation),andaligntheinstrumentatthemeasuringstationwiththeleftsideoftheinstrumentaimingattheorientationpointsothatthedirectionoftheinstrument'ssightlineisconsistentwiththecoordinatedirectionangleofthestraightline,completingthetotalstationorientation.andautomaticallystoreit.全站仪碎部点数据采集TotalStationDataCollectionforDetailPoints观测碎部点时，以该方向为起始，顺时针转动仪器瞄准碎部点，仪器会记录下转动的水平角，并根据起始边的坐标方位角加上转动的水平角从而推算出仪器到碎部点的视线所对应的坐标方位角，并利用仪器的距离测量功能，实测出仪器到碎部点的距离，并根据坐标正算方法，从而推算出仪器到碎部点的坐标增量和高差，并根据测站点的坐标加上坐标增量和高差自动计算出碎部点的位置信息（X、Y、H）并自动存储。Whenobservingfragmentpoints,startfromthisdirection,turntheinstrumentclockwisetoaimatthefragmentpoints.Theinstrumentrecordsthehorizontalangleoftherotation,calculatesthecorrespondingcoordinatedirectionangleoftheinstrumentsightlinetothefragmentpointbasedontheinitialside'scoordinatedirectionangleplusthehorizontalangleoftherotation,andmeasurestheactualdistancebetweentheinstrumentandthefragmentpointusingtheinstrumentdistancemeasurementfunction.Then,theinstrumenttothefragmentpoint'scoordinateincrementandheightdifferencearecalculatedaccordingtothecoordinateforwardcalculationmethod,andthepositioninformation(X,Y,H)ofthefragmentpointisautomaticallycalculatedandstoredbasedonthecoordinateofthemeasuringstation,thecoordinateincrement,andtheheightdifference.全站仪碎部点数据采集TotalStationDataCollectionforDetailPointsTotalStationSettings全站仪设置1观测开始前一定要对仪器进行基本参数的设置：温度气压改正、棱镜常数设置、观测模式设置、仪器补偿器设置。

Beforeobservation,itisnecessarytosetbasicparametersoftheinstrument,includingtemperatureandpressurecorrection,prismconstantsetting,observationmodesetting,andinstrumentcompensatorsetting.TotalStationSettings全站仪设置2已知点数据的准确性检查。Checkingtheaccuracyofknownpointdata.TotalStationSettings全站仪设置3保证测站点、定向点坐标输入无误，并准确瞄准定向点，从而让仪器视线与已知边方位角一致。Ensuringthatthecoordinatesofthemeasuringstationandorientationpointareinputcorrectlyandaccuratelyaimingtheorientationpoint,sothattheinstrumentsightlineisconsistentwiththeknownsideazimuth.TotalStationSettings全站仪设置4同时要准确量取仪器高和目标高，从而保证高差的准确性。Atthesametime,itisnecessarytoaccuratelymeasuretheinstrumentheightandtargetheighttoensuretheaccuracyoftheheightdifference.TotalStationSettings全站仪设置5盘左定向、盘左观测，观测过程中不要变换盘位。Orienttotheleftandobservetotheleft,anddonotchangethepositionduringtheobservationprocess.

原理：通过架设基准站和移动站，同步接收卫星信号进行定位，同时基准站把接收后的定位信息发送给移动站，移动站在接受卫星信号的同时还接受到基站信号进行差分计算，从而实现精度达到厘米级的定位。GNSSRTK碎部点数据采集GNSSRTKFragmentPointDataCollectionPrinciples:Bysettingupareferencestationandamobilestationtosynchronouslyreceivesatellitesignalsforpositioning.Thebasestationsendsthepositioninginformationafterreceivingsatellitesignalstotheroverstation.Theroverstationreceivesbothsatellitesignalsandbasestationsignalsandperformsdifferentialcalculationstoachievehigh-precisionpositioning.GNSSRTKcoordinateconversionGNSSRTK坐标转换WGS-84coordinatesAtleastthreecommonpointsneedtobeusedforcalculatingseven-parameterstransformations,whicharecommonlyusedinlarge-scaleplanarcoordinatesystemconversions.至少需要3个公共点计算转换七参数，适用于大范围空间坐标系转换。Atleasttwocommonpointsneedtobeusedforcalculatingfour-parametertransformations,whicharecommonlyusedinsmall-scaleplanarcoordinatesystemconversions.至少需要2个公共点计算转换四参数，适用于小范围平面坐标系转换。WGS-84坐标WGS-84coordinates四参数转换Thefour-parametertransformation七参数转换Theseven-parametertransformationGNSSRTKoperationprecautionsGNSSRTK操作注意事项移动站的观测设置Observationsettingsforthemobilestation已知点的分布Thedistributionofknownpoints已知点可靠性检查Reliabilitycheckforknownpoints减弱已知点的观测误差Reducetheobservationerrorsoftheknownpoints目标坐标系取决于已知点坐标系Thetargetcoordinatesystemdependsonthecoordinatesystemoftheknownpoints.钢尺量距进行碎部点采集SteelTapeMeasurementforCollectingFragmentPoints原理：利用全站仪、RTK采集地物外围特征点为基准点、基准线，使用钢尺量距的方法来进行细部碎部点的位置确定。Principle:UsingatotalstationorRTK,measuringperipheralcharacteristicpointsofanobjectasreferencepointsandreferencelines,thenusingasteeltapemeasuretodeterminethepositionsofdetailpointsiseffective.钢尺量距作业方法TheSteelTapeMeasureMethod定向直角法：量距以基准线垂直。Directionalrightanglemethod:Themeasurementdistanceisperpendiculartothereferenceline.钢尺量距作业方法TheSteelTapeMeasureMethod距离交会法：通过以基准点为圆心，量距为半径作圆，不同半径圆的交点即为碎部点位置。Distanceintersectionmethod:Throughthecenterofthebenchmarkpoint,withthedistanceastheradiustodrawacircle,theintersectionpointofthecirclewithdifferentradiiisthelocationofthefragmentarypoint.钢尺量距作业方法TheSteelTapeMeasureMethod内插、延长线法：以基准线为依据，在基准线内部量距内插或者量距延长确定碎部点位置。Interpolationandextensionmethod:Basedonthebaseline,measurethedistanceandinterpolateorextendtodeterminethelocationofthefragmenta