DGPS ased Naionwide Highway Suveying in China Pengfei CHENG, Xiyin LI, Li ZHANG Yanhui CAI, Xiuuan WU and Jingbin LIU, China Key wods: DGPS, Highway Newok SUMMAY The highway newoks a naional and povinial levels in China abou 3,km lengh had been suessfully suveyed based on he vehile bone DGPS mehod poposed by his pape. In his pape he auhos pesen deailed woking flow ha in apidly olleing geomei daa and aibues of highway feaues, algoihms used fo poessing DGPS daa, and a sofwae pakage developed fo his appliaion. Though lage sale highway daa olleion i poves he developed sysem an damaially impove he effiieny and auay in field daa olleion. Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 1/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24
DGPS ased Naionwide Highway Suveying in China Pengfei CHENG, Xiyin LI, Li ZHANG Yanhui CAI, Xiuuan WU, Jingbin LIU, China 1. INTODUCTION The highway mileage in China had eahed abou 1.7 million kilomees by he end of 21. Fo suh lage sale suveying wok, wo mehods ae onsideed, i.e. saellie image suveying and vehile aied DGPS suveying. The elaive advanage of he DGPS mehod exiss as Highe Auay The auay of DGPS is bee han 5 mees 1 while he esoluion of SPOT-4 image is only 1 mees. Fuhe Infomaion Muh moe eesial obes suh as gas saions, bidges and hei aibues an be olleed unde vehile aied DGPS ondiion. Lowe Cos The expense on he saellie image puhase and image poessing is muh moe han DGPS way. Fo insane, a 6km 6km SPOT-4 image oss abou CN 1, while he expense of vehile aied DGPS fo 6km 6km is less han CN 2,. Consideing hose faos, he Sae ueau of Suveying and Mapping of China adops he DGPS mehod fo he developmen of anspo laye in he 1:5, sale naional fundamenal geogaphi daabase. The flow ha of he vehile aied DGPS highway suveying is given as Fig. 1. GPS obsevable Field daa olleion DGPS poessing Obe/Aibue Coodinae seam Obe mahing Mapping/D Obes: Coodinaes Aibue 1 Wih SA poliy uning off Fig. 1: Flow ha of he vehile aied DGPS highway suveying Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 2/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24
2. FIELD DATA COLLECTION Many eams oined he field wok. Eah field eam is onfigued wih one base saion and one o moe oves. Suveying eeives ae equipped on boh base saions and oves. Lapops wih speial designed eoding sofwae ae also needed fo he oves. The main puposes of he eoding sofwae ae 1 o eod he eesial obes and hei aibue, and 2 o eod he peise epohs of he obes. This leads o wo key poblems, he oganizaion of diffeen kinds of obes and he synhonizaion of eoding ime wih GPS ime. 2.1 Obe Daa Suue An obe/aibue able file is used in he sofwae wih he following basi suue idge 432 MPA 7 Name CH 3 Maeial CH 2 Widh FLT 1.2 Lengh FLT 1.2 Using C obe oiened pogamming, diffeen kinds of obes an be aessed in he simila way. 2.2 Time synhonizaion The ime on he lapop is synhonized o he GPS eeive wih he NMEA inefae. The diagam is shown as blow Communiaion head eoding head GPS Time? N Even? N GPS v Y Y Even Inpu eive Compue Time eive Compue Time GPS COMP GPS COMP Fig. 2: Time synhonizaion beween Compue and GPS Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 3/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24
Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24 4/7 3. DGPS POCESSING Loal Aea Diffeenial GPS LADGPS pos poessing model is used in his poe. 3.1 Algoihm Aoding o he LADGPS model, he base saion is se up on a sie wih known oodinaes, and he obsevaion equaion fo saellie is given as 1 whee is he pseudoange obsevable fo saellie, is he geomey disane fom saellie o sie, is he bias of obsevable aused by he popagaion oue, is he bias of obsevable aused by he saellie and is he bias of obsevable aused by he eeive and is gound envionmen. As an be alulaed fom he known oodinae of saellie and sie, he oeion fo he pseudoange, namely PC, an be alulaed by PC 2 Is deivaive wih espe o ime is alled C, PC C d d 3 So PC a ime an be alulaed as fomula C PC PC 4 Obseve equaion on he ove is given as 5 Afe applying he oeion deived fom PC and C C PC o 6 Duing a limied em, PC an be onsideed as ime-invaian, so o & 7
Wihin a limied aea, due o he song oelaion beween and, o & 8 I shows ha he biases aused by saellie and popagaion ae mainly emoved. Caiephase aided ode smoohing is also adoped o impove he auay. 3.2 Auay Tes Compaison wih sai GPS poin an give he DGPS poining auay. Two expeimens have been done, one in he Xi an-aoi expess way, whih is 17km s long in wes-eas dieion and anohe on he Xi an-linong highway, whih is 12km s long in noh-souh dieion. The esul he hose ess is give as blow ias 2 ~2.5 2.5~5. 5.~7.5 7.5~1 >1 Maximum Poin Num. 16 14 8 5 1 Peen 36.4 31.8 18.2 11.4 2.2 12.2 4. OJECT-COODINATE MATCHING Fom one eesial obe s sa and end epoh eoding in field, he oesponding oodinaes of he obe an be eieved. The Diagam is shown as blow Obe eod TYP, S/E EPOCHS, ECC GPS esul Time/CD Seam Oienaion Inepolaion ECC Coeion Final Obe Fig. 3:Diagam of Obe-Coodinae Mahing 2 The expeimen is implemened befoe he SA uning off Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 5/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24
1,X,X 2,X,X X X T x T,y T X T x T,y Fig. 4: Diagam of eeniiy oeion Fo hose ae no igh on he ae of vehile, as illusaed in Fig.4, an eeniiy oeion should be implemened. The oeion elies on dieion of he vehile s speed and he quaniy of eeniiy. The fomula of oeion is given as 1 xt x osan dy / dx π / 2 9 1 y y sinan dy / dx π / 2 5. CONCLUSION T The highway newoks a naional and povinial levels in China abou 3,km lengh had been suessfully suveyed based on he vehile bone DGPS mehod. Now highways a he ouny and ownship level ae being suveyed. The whole poe was ompleed a he end of 23. EFEENCES Junyong Chen, eal Time Posiioning Tehnique of GPS: Developmen in Suveying Tehnologies, Vol.97, 1996.2 Jingnan Liu, Junyong Chen, e al., Piniple and mehod of Wide Aea Diffeenial GPS, Pess of Suveying and Mapping, 1998 Pengfei Cheng, Xiyin Li, e al., Key Tehnologies of DGPS in 1:5, Highway Suveying, Siene of Suveying & Mapping, 2, No.1, P34-36..Hofmann-Wellenhof, e al., GPS Theoy and Paie Fouh ediion, Spinge,1997 Pengfei Cheng, Invesigaions on he Esablishmen of DGPS Sevies in China, PhD Thesis, Tehnial Univesiy of Gaz, 1998. U. Hugenoble, e al., enese GPS Sofwae Vesion 4.2, Asonomial Insiue Univesiy Of ene, 21. Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 6/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24
CONTACTS Pofesso, D Pengfei Cheng Chinese Aademy of Suveying and Mapping 16 eiaiping oad, 139 eiing CHINA Tel. 86 1 8822 9385 Fax 86 1 6821 8654 Email:pfheng@publi.ba.ne.n Web sie: hp://www.asm.a.n/ Session 9 - Suveying Duing Consuion and Planning Pengfei Cheng, Xiyin Li, Li Zhang, Yanhui Cai, Xiuuan Wu and Jingbin Liu TS9.4 DGPS ased Naionwide Highway Suveying in China 7/7 1 s FIG Inenaional Symposium on Engineeing Suveys fo Consuion Woks and Suual Engineeing Noingham, Unied Kingdom, 28 June 1 July 24