Geoinformatics Dieter Fritsch, Institute for Photogrammetry, University of tuttgart Copyright: Institut fuer Photogrammetrie, Univ tutgart 1 Geoinformatics Every Tuesday, 6-8pm Labs & Assignments Prof. Dr. Dieter Fritsch Institute for Photogrammetry () Geschwister-choll-tr. 24D 70174 tuttgart dieter.fritsch@.uni-stuttgart.de 1
Geoinformatics, GI-Monographs, Books D. Ian Heywood, arah Cornelius, teve Carver, Ian Heywood: An Introduction to Geographical Information ystems, 2nd Edition 2002, Prentice Hall. Christopher Jones: Geographical Information ystems and Computer Cartography, Addison Wesley Longman Ltd., Harlow, 1997. Michael Worboys: GI A Computing Perspective, Taylor and Francis, 1995.. Aronoff: Geographic Information ystems: A Management Perspective, WDL Publications, Ottawa, Canada, 1991. 1. Introduction - What about Geodata? Geodata: data elements which are referenced to a part of the earth satellite data aerial data (here combined with laser data) 2
1. Introduction - What about Geodata? topographic maps in different scales street network data 1. Introduction - Car Navigation 3
1. Introduction - Geodata Thematic Maps 1. Introduction Geodata: 3D ielmingen (before planned add-in) Institute for Photogrammetry, Univ. tuttgart 4
1. Introduction Geodata: 3D ielmingen (after planned add-in) Institute for Photogrammetry, Univ. tuttgart 2. Geospatial Data Collection GI data acquisition - disciplines and techniques primary and secondary data acquisition Data sources Manual data acquisition (emi) automatic data acquisition Geospatial Infrastructures (Internet, Cloud ervices, Apps, etc.) 5
2. Geospatial Data Collection Disciplines & Techniques Primary data acquisition: acquisition directly from the object or an image Geodesy: GN/GP observations, leveling, angles, distances, theodolites and tachymeters, laser scanners, Photogrammetry: Monoplotting, stereoplotting, tructure-from- Motion, Dense Image Matching, Airborne Laser canning, L, Mobile Mapping, PA/UA etc emote ensing: classification, Georelated and specific sensors, field inspections, other disciplines econdary data acquisition: acquisition of already interpreted data Cartography: Map digitizing, map scanning Modern Cartography: Automated and/or semi-automated feature extraction 2.1 GN/GP An Introduction GN Global Navigation atellite ystem GP more precise NAVTA - GP : Navigation ystem with Time and anging - Global Positioning ystem Content: Intro Historical developments ystem definition GP positioning GP observation methods Coordinate transforms GI1 12 6
2.1 GN/GP - Global Positioning ystem ystem data: 24 satellites (at present 27 active) 6 orbits with inclination 55 orbit distance ca. 20200km 1 cycle ca. 12 h availability worldwide, 24 h accuracy P horizontal <30m (95%) vertikal < 60m (95%) Copyright: Institute for Photogrammetry, Univ tuttgart 13 2.1 GN/GP - Historical Developments I tart atellite Geodesy: October 4th, 1957 (putnik) 1958 tart development TANIT Navy Navigation atellite ystem (NN) of U Marine ervice with up to 8 satellites in polar orbits (~1000km distance). Observations: Dopplerhifts. TANIT was used till 1964 for military purposes, from 1967 public apps - in the 1980s geodetic positioning with TANIT ab 1973 Design of NAVTA-GP: more satellites in higher orbits, systematic and sufficient controlled orbits, very stable und structured satellite signals for TOF measurements 1978-1985 up to 7 Block I GP satellites 28.01.1986 T Challenger exploded 1989-3/1994 24 operationel GP satelliten Block II/IIA > 1994 Block II -GP satelliten Copyright: Institute for Photogrammetry, Univ. tuttgart 14 7
2.1 GN/GP - Historical Developments II Initial Operational Capability (IOC): Operation guaranteed till 01.01.2005 tandard Positioning ervice (P): (Navigation) Accuracy ~100[m] Differential Positioning ervice (DGP) ange : Pseudoranges, Accuracy~2-5[m] Differential Positioning ervice (DGP) ange+phase : Pseudoranges und Phasen, Acc. ~1-10[cm] GP pace egment GP Control egment GP User egment 1994 ready-to-go improves continously Broadcast Ephemerids GP eceiver Technology, continously improved Copyright: Institute for Photogrammetry, Univ. tuttgart 15 The GP principle: 2.1 GN/GP The Principle The distance between receiver and satellite is measured using the principles of electronic distance measurement 2 pseudo range 1 3 c( t t i i ) p 1 ~ 1 t x c t i t i Pseudo range between receiver and satellite Velocity of Light eceiver clock epoch i atellite clock epoche i 4. satellite has to be observed Why? Copyright: Institute for Photogrammetry, Univ. tuttgart 16 8
1 2.1 GN/GP The Principle Base lines and error reductions: Z C Y X 2 1 x x x 1 x b 2 Dominant, system-dependent error sources, e.g. wrong orbit parameters have the same impact onto neighbored terrestrial points elative accuracy > absolute accuracy geodetic apps: simultaneous obs with at least 2 receivers Also distances of 10 km are neighbored - there is no direct view between 1 and 2 necessary Copyright: Institute for Photogrammetry, Univ. tuttgart 17 9