Accuracy Assessment for 3-D Target Coordinates Estimation Using GPS & Total Station

Transcription

1 Madi et.al. Iraqi Journal of Science, Deceber 2012, Vol. 3, o. 4, Pp Accuracy Assessent for 3-D Target Coordinates Estiation Using GPS & Total Station Aala S. Madi, abeel J. Tawfiq, & Ali k. Hussein College of Science, University of Bagdad, Bagdad, Iraq yaoo.co Abstract Te Target coordinates estiation in te real world (3-D) was iportant applications in te geodesy and any reote sensing applications, for tis purpose, te GPS/DGPS, and te Total Station were used to create and estiate te new target coordinate. In tis paper, te Total Station Leica 1200 wit Garin navigator GPS were used to extract te 3-D coordinates of target fro te easureent of TS position. For six point for one station. Te Garine GPS navigator was use to find te coordinates for eac points and te total station position. Many ateatical process were used to evaluate te results of accuracy using written subroutines in Matlab (version R 2007a) environental. Keyword: Atosperic correction, te Total Station Leica 1200,GPS ( ). Garin TS1200..Matlab ( version ) R 2007a 930

2 Madi et.al. Iraqi Journal of Science, Deceber 2012, Vol. 3, o. 4, Pp Introduction Te Global Positioning Syste (GPS) navigation syste positioning is one of te ost popular topics in civilian applications. orally, GPS can be used to collect te land use cange inforation successfully and quickly. However, GPS doesn t work due to te overead obstructions, suc as in urban areas or under trees. Ten, all conventional terrestrial survey etods, suc as total station (TS), can be used to aid GPS Since te collected land use cange inforation using eiter GPS or total station syste will be entered to an existed land anageent syste. Hence, te land use cange styles of te interested region could be classified into a certain nuber of groups fro te point view of Geograpic Inforation Syste (GIS). In order to reduce te field surveying works of GPS and/or (TS), it is necessary to design an optiized and effective field surveying procedure by eans of analyzing te land use cange styles and environental caracteristics of te interested region.[1] [2]. Figure 1- Te Etrex Vista Gariavigator GPS Figure 2- Te Leica Total Station TPS120 2.Te Devices Used Te Etrex vista Garin avigator GPS and Total Station Leica TPS1200 ave been used in order to extract te coordinates of targets. Te GPS was used to navigate te total station coordinates as well as te easured point in te TS, were te TS used to estiate te target (reflector) coordinates. Tables 1 and 2, figures 2 and 3 sown te devises used and teir specifications. 3. Region of Interest Study area located in te iddle of Iraqi country (i.e. Bagdad University Copass), Latitude (33º 16'.6") to (33º 16' 4."), Longitude (44º 22' 11.8") to (44º 23' 20.4") E. Te project site is Deanery College of science, Te area of te site is 2 wide, 100 long and 8.71eigt, Te test site s scene is pictured wit a digital caera in Figure (3) Figure 3- Station-1 Location 931

3 Madi et.al. Iraqi Journal of Science, Deceber 2012, Vol. 3, o. 4, Pp Table 1- Specifications of te Etrex Vista Garin avigator GPS, [3] Accuracy Unit diensions, WxHxD: Display size, WxH: Display resolution, WxH: Display type: Weigt: Battery: Battery life: (about 1 to 100). 2.0" x 4.4" x 1.2" (.1 x 11.2 x 3.0 c) 1.1" x 2.1" (2.8 x.4 c) 160 x 288 pixels 4 level gray LCD.3 oz (10 g) wit batteries 2 AA batteries (not included) 12 ours Table 2- Specifications Of Te Total Station Leica TPS1200, [4] 1.Angle Measureent Accuracy Hz, V Display resolution (standard deviation, ISO ): Copensator Working range Setting accuracy (0.1 gon) 4 (0.07 gon) 0. (0.2 gon) 2.Distance Measureent (average atosperic conditions) Range Round pris (GPR1): Range 360 reflector (GRZ4): Range Mini pris (GMP101) Sortest easurable distance Measureent Tie Accuracy 3.Telescope Magnification Free objective aperture Field of view ~ 1. s 1 +1pp 30 x (1.66 gon) / 2.7 at Result And Discussion In tis paper te Total Station and GPS were used to estiate te coordinates syste for a one station, te station consist of 6 easureents points. Te table and figure represent te station 1 easureents and te figure. Te TS1 colun represents te estiated coordinates (UTM projection, WGS- 84 Datu) by TS for eac reflector point in te station. Te GPS colun represents te navigated coordinates by te GPS in te reflector position. Te accuracy colun represents te GPS accuracy at tat point during te navigation. Te Sat. o. colun represents te nuber of captured satellite at tat point. Finally, te last colun sow te point eigt in. Station -1 Specification Data: Heigt T.S Heigt ref on deanery. ref eigt of denary a Te station corr. E= , = H=33.24, A=6, uber of sat=, 932

4 Madi et.al. Iraqi Journal of Science, Deceber 2012, Vol. 3, o. 4, Pp Table 3- Te Coordinates Of TS And GPS For Station 1 TS1 GPS Accurac y 7 Sat. o. Heigt E E E E E E E E E E E E E E E E E E A subroutines written in atlab used to correct te easureents fro atosperic errors according to Leica Geosystes correction tools for infrared total station given as, [], * P 4.126*10 * H x D= * 10 (1) (1+ α t) (1+ α t) Were; D = atosperic correction [pp] for eac k p = air pressure [bar] t = air teperature [ C] H = relative uidity [%] α = 1 / * t x= t (2) Table 4, represents te weatering condition at te data of easureents, Table 4- Te Weatering Paraeters at Date of Measureents For Station -1 Max te. C 40 Min te. C 22 Pressure bs 00 Relativity uidity 3-40 According to available paraeters and fro applying equations 1 and 2, te weatering correction value D= witin te 1 k. Calculate te coordinates easureents difference between te TS1 and GPS values wit out correction. Te difference values for eac point given te table (). Table - Te Difference Values For Station -1 o E, , , After applying te atosperic correction to difference results te values for E, and, can be given in table (6), note tat te value of dose not corrected because te navigator easureents for was already ig error. Te distance between points and TS were ranged ( ), so, te correction value can be given as

5 Madi et.al. Iraqi Journal of Science, Deceber 2012, Vol. 3, o. 4, Pp Table 6- Te Difference Values After Atosperics Correction For Station -1 o E, , , Fro table 6, te error in orting coordinates was greater tan te error in te Easting direction. Tis was due to te GPS navigation errors wic was out of scope of tis paper. Te average error in Easting direction was Te error value was not sall tis was due to any factors influencing te easureents. References [1] Lin, L.S., 2003,Integrating of GPS and Total Station for Land Surveying of Urban Region. In: Te 1st Taipei International Conference on Digital Eart, Cinese Cultural University, Taipei, Taiwan, oveber 18-19, o. C1-12, pp1-10. [2] Wolf, P.R. & Gilani, 2002, C.D Eleentary Surveying An Introduction to Geoetrics. Prentice Hall, Upper Saddle River, ew Jersey, pp [3] Etrex Vista Garin avigator, 2007,User anual, Garin International, Inc.1200 East 11st,USA. [4] Canary Systes, 2006, Inc., TPS1200 Total Station USER S GUIDE, 7 ewport Road, Suite 211, ew London, H 0327 USA. [] Eleonora Bertaccini, Alessandro Capra, Cristina Castagnetti, Alessandro, 2008, "Atosperic corrections for topograpic onitoring systes in landslides", TS06G - GSS and Land Deforation (Flas),