1 / 54

Bill Henning Senior Geodesist, PLS. 301-713-3196 x 111, william.henning@noaa

GREAT LAKES REGION HEIGHT MODERNIZATION CONSORTIUM BACKGROUND ON REAL TIME POSITIONING. Bill Henning Senior Geodesist, PLS. 301-713-3196 x 111, william.henning@noaa.gov. ftp://ftp.ngs.noaa.gov/dist/whenning/GLRHMC/. THE CHANGE FROM LABOR INTENSIVE TO TECHNOLOGY!. CHANGE……. 2000+/-.

ruby
Download Presentation

Bill Henning Senior Geodesist, PLS. 301-713-3196 x 111, william.henning@noaa

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. GREAT LAKES REGION HEIGHT MODERNIZATION CONSORTIUM BACKGROUND ON REAL TIME POSITIONING Bill Henning Senior Geodesist, PLS. 301-713-3196 x 111, william.henning@noaa.gov ftp://ftp.ngs.noaa.gov/dist/whenning/GLRHMC/

  2. THE CHANGE FROM LABOR INTENSIVE TO TECHNOLOGY!

  3. CHANGE……. 2000+/- 23 YEARS 1977

  4. A CONFLUENCE OF TECHNOLOGY- USE OF RTK • INTERNET DATA VIA CELL TECHNOLOGY • SOFTWARE/FIRMWARE ALGORITHMS • GNSS HARDWARE • SATELLITE CONSTELLATIONS • SATELLITE CODES/FREQUENCIES

  5. CHANGE……. GLOBAL NAVIGATION SATELLITE SYSTEMS (GNSS) • POTENTIAL FUTURE DEVELOPMENTS • (2005 – 2017?) • GPS MODERNIZATION – BLOCK IIF & III • GLONASS ENHANCEMENTS (K & M) • EUROPEAN UNION - GALILEO • CHINA - COMPASS • 115+ Satellites • Second and Third Civil Frequency - GPS • No Signal Encryption - GLONASS & GALILEO • More Robust Signal Transmissions • Real-Time Unaugmented 1 Meter (or better!) Accuracy

  6. 1-3 m CHANGE……. STANDALONE POSITIONING: BY 2017? • L2C • L5 CARRIER • New Code on L5 • L1C 10-15 cm??? 2000 ERROR BUDGET (POST S/A) BETTER RESISTANCE TO INTERFERENCE FASTER AMBIGUITY RESOLUTION AUGMENTED CODE APPLICATIONS GET USED TO ACCELERATED CHANGE-PREPARE TO ADAPT

  7. II. INS & OUTS OF REAL-TIME NETWORKS

  8. NEW PLAYERS IN ”HIGH-ACCURACY” REAL-TIME POSITIONING • √GIS – INFRASTRUCTURE, SIGNAGE, ENVIRONMENTAL, PHOTO CONTROL • √AGRICULTURE • √MACHINE CONTROL • DEFORMATION MONITORING • TECTONIC/SEISMIC STUDIES • NAVIGATION TO/FROM PORTS • REMOTE SENSING/MAPPING – LIDAR • FAA – NAVIGATION, LANDING, TAXIING • (WEATHER SCIENTISTS – CO-LOCATED RT IONO/TROPO SENSORS)

  9. GIS – INFRASTRUCTURE, SIGNAGE, • ENVIRONMENTAL, PHOTO CONTROL

  10. Real Time for Agriculture • AGRICULTURE DUAL FREQUENCY CARRIER RTK – NOT CODE

  11. GRADE STAKES ARE BECOMING A RARITY ON LARGE SITES AND ROAD PROJECTS…. • MACHINE CONTROL Machine Control CONTROL IS MOVING FROM SINGLE-BASE ON SITE TOWARD RTN Slide by Jim Waters, TNDOT Graphics Courtesy of Caterpiller Inc.

  12. RT DEFORMATION MONITORING- BRIDGES, BUILDINGS, DAMS, LEVEES, SUPPORT WALLS TRIPLE DIFFERENCING & KALMAN FILTERING

  13. NAVIGATION TO/FROM PORTS- • ELLIPSOID HEIGHTS • Representatives of the maritime industry unofficially estimate that NDGPS reference stations near ports and harbors would cause an annual increase of $16 billion in cargo value in domestic waters, and an annual increase of $640 million in tax revenue, or a $9.6 billion benefit over the projected15-year life of the NDGPS. • SOURCE: National Height Modernization Study Report to Congress U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service National Geodetic Survey June 1998

  14. DEM - Digital Elevation Model Flood Zone Boundary Red –Original Blue – Improved with LIDAR Height Modernization OLD FIRMS – SCALED HORIZONTAL LIDAR and Derivative Products CONTROLLED FROM RTN (Light Detection and Ranging ) REMOTE SENSING/MAPPING – LIDAR (currently around an order of magnitude less precise than classical RTK, ie. .1 – .4 m) OLD REMOTE SENSING Slide by Gary Thompson, NC Geodetic Survey

  15. FAA – NAVIGATION, LANDING, TAXIING Aviation User Requirements – GPS / Nav • Hazards • Signal effect (Ionospheric delay) • Scintillation (ADS-B impacts) • Radio bursts • Satellite effects • Need information on real-time GPS errors (horizontal, vertical) • WAAS, LAAS office input on requirements • NextGen requirements NATIONAL WEATHER SERVICE/SPACE WEATHER PREDICTION CENTER Mike StillsCaptain Bryn JonesJoe Kunches United Airlines, USA SolarMetrics Limited, UK Space Weather Services Branch NOAA Space Weather Prediction Center Boulder, Colorado, USA Aviation Workshop NOAA SWPC Space Weather Workshop Boulder, Colorado April 28, 2008

  16. WHO IS RUNNING RTN IN THE USA?PUBLIC/PRIVATE COOPERATIVES ARE EMERGING • ACADEMIC/SCIENTIFIC • SPATIAL REFERENCE CENTERS • VARIOUS DOTS • COUNTY • CITY • GEODETIC SURVEYS (NC, SC) • MANUFACTURERS • VENDOR NETWORKS • AGRICULTURE • MA & PA NETWORKS RAPIDLY GROWING

  17. RTK vs. RTN RTN RTK

  18. WHY NETWORK RTK (RTN)? Because the requirement for a user base station is removed: • No reconnaissance/recovery of passive control • No time lost setting up and breaking down a base • No base baby sitting, therefore labor cost is reduced No base means with two rovers the project is completed in half the time OR the user would only need one rover • = $$$ savings

  19. WHY NETWORK RTK (RTN)? NO (1ST ORDER)DISTANCE CORRELATED ERROR - Atmospheric, ephemeris corrections for the site of survey Data degrade gracefully outside of the network or if a reference station is down RTNS CAN BE SEAMLESSLY CONNECTED TO THE NSRS – This means: Regional inter-GIS compatibility Continual accuracy and integrity monitoring Easy datum adjustment/change updates for the user In other words - “Everything fits together” NSRS

  20. ALL RTN SOLUTIONS END IN A SINGLE BASELINE SOLUTION, I.E., A DIFFERENTIAL VECTOR FROM A “KNOWN” POINT RTN FLAVORS • NON-PHYSICAL RS – DUPLEX COMMS • MAC – DUPLEX OR BROADCAST COMMS • FKP – BROADCAST COMMS

  21. ALL IN ROVER • No control center or “master” station • All observables from all reference stations are sent to rover • Rover does all modeling of corrections and processes baseline • Major horsepower is needed at the rover, but eliminates the possibility of errors from differing modeling methods by different hardware. CLOSEST STATION Rover uses broadcast from closest reference station Single baseline, no network modeled corrections Typically a Ma & Pa network of “antennas on the roofs” Back to accounting for 1 PPM error REVERSE PROCESSING Rover sends observables to Server Server processes data and returns position to Rover

  22. RTN BIG PICTURE ISSUES • PASSIVE / ACTIVE – WHAT IS ‘TRUTH’? • GEOID + ELLIPSOID / LOCALIZE – QUALITY OF GEOID MODELS LOCALLY. ORTHOMETRIC HEIGHTS ON CORS? • NATIONAL DATUMS / LOCAL DATUMS / ADJUSTMENTS- DIFFERENT WAYS RTN GET THEIR COORDINATES-VARIOUS OPUS, OPUS-DB, CORS ADJUSTED, PASSIVE MARKS. VELOCITIES - NEW DATUMS, “4 -D” POSITIONS • GNSS / GPS • ACCURACY / PRECISION- IMPORTANCE OF METADATA • SINGLE SHOT / REDUNDANCY • RTK / RTN • GRID / GROUND – LOW DISTORTION PROJECTIONS- SHOULD NGS PLAY?

  23. CHANGE IN ACCESSING THE NSRS BY PASSIVE TO ACTIVE MONUMENTATION EXAMPLE: GNSS DERIVED HEIGHTS 5 1/2 HOURS - HARN 30-45 MINUTES NETWORK PASSIVE • NOS-NGS 58 WITH DRAFT ORTHO GUIDELINES-0.05 m TO NSRS, 0.02 m LOCAL • DGPS – 15 SECONDS, 0.5 TO 2 m • OPUS > 4 HRS = 0.02 M (h), 0.05 (H) • CORS- SAME AS OPUS • OPUS-RS 15 MINUTES =0.10 m • SINGLE BASE RTK- “IT DEPENDS!” 5 SECONDS (better than 0.03 m expected) • RTN – “IT DEPENDS!” 5 SECONDS ( better than 0.04 m expected) STATIC ACTIVE 2-4 HOURS STATIC 10-30 MINUTES REAL-TIME 5 SECONDS - 3 MINUTES

  24. PASSIVE vs. ACTIVE MONUMENTS SOME CONSIDERATIONS: • NAD 83 IS REALIZED BY THE NATIONAL CORS • NAVD 88 IS REALIZED BY HIGH ACCURACY & STABLE PASSIVE MARKS(DIFFICULT TO MAINTAIN) • PASSIVE MARKS ARE A SNAPSHOT IN TIME • ACTIVE STATIONS ARE 4-D • PASSIVE MARKS CAN BE MANDATED IN STATE ANNOTATED CODES • RTN CAN ENCOMPASS MANY STATES AND RUN ACROSS MANY CLASSICAL & GPS CAMPAIGNS OF VARYING TIME AND ACCURACY. • PASSIVE MARKS USED IN DESIGN ARE PROJECT “TRUTH” • DIFFERENT RTN CAN BE REALIZED IN DIFFERENT DATUMS AND ADJUSTMENTS

  25. HARD TO ACCESS PASSIVE MONUMENTS

  26. Monumented Points Deterioration Disturbed Geodetic Control Coordinates/Elevations Questionable! Destroyed Geodetic Control No Coordinates/Elevation

  27. MISSING MARKS- TYPICAL EXAMPLE DAVE ZILKOSKI’S BASEMENT

  28. WHEN WAS THE MONUMENT LAST LEVELED? 1957 1991

  29. NEW JERSEY ANNOTATED CODE-PASSIVE MARKS

  30. Movement from passive monumentation towards Active monumentation and from traditional positioning and traversing towards RT positioning via GNSS RTN is a movement from 3-D positioning towards 4-D Positioning in most of the conterminous USA.This necessitates the recordation of metadata: source of coordinates, datum, datum epoch, alignment to the NSRS, grid/ground, date of field survey, antennas, GNSS gear, etc.

  31. SANTA CRUZ, CA NAD 83 VELOCITIES (GOLD) ITRF 2000 VELOCITIES (BLUE)

  32. ORTHO HEIGHTS - LOCALIZE OR NOT? • PASSIVE MARKS ARE A SNAP SHOT OF WHEN THEY WERE LEVELED OR DERIVED FROM GPS • IF YOU BUILD FROM A MONUMENTED BM AND THE DESIGN WAS DONE REFERENCED TO IT, IT IS “THE TRUTH”, UNLESS IN GROSS ERROR. • LOCALIZATIONS ARE A GOOD WAY TO NOT ONLY LOCK TO THE SURROUNDING PASSIVE MARKS, BUT ALSO TO EVALUATE HOW THE CONTROL FITS TOGETHER. • HOW GOOD IS THE NGS HYBRID GEOID MODEL IN YOUR AREA? GEOID 09 IS THE CURRENT MODEL

  33. ELLIPSOID, GEOID & ORTHO HEIGHTS EACH COMPONENT HAS ERRORS H88 = h83 – N09

  34. NGS Data Sheet - GEOID03 Published NAVD88 to GPS Derived GEOID96 = 0.17 m GEOID99 = 0.11 m GEOID03 = 0.05 m GEOID09 = 0.017 m h - N H = -(-32.60) 69.78 102.431 = 102.431102.38

  35. RT DERIVED ELEVATION CHOICES • “INCLINED PLANE”“LOCALIZATION” = PROPER TIE TO PASSIVE CONTROL (IMPROPER HINGED LOCALIZATION) • “GEOID XX” (MODELED + ELLIPSOID) • “ELLIPSOID ONLY” (GNSS VERTICAL DIFFERENCE ONLY) • LOCALIZATION + GEOID = METHOD OF CHOICE!

  36. BEST FIT PLANAR PROJECTION TO PASSIVE MARKS (CALIBRATIONS/LOCALIZATIONS)

  37. PASSIVE/ACTIVE ORTHOS

  38. GNSS TO ANY DATUM • GNSS ECEF X,Y,Z (WGS 84 & PZ90) NAD 83(,,h) SPC N,E,h + GEOID XX = SPC N,E,H OR CALIBRATE TO 4-5 SITE POINTS IN THE DESIRED DATUM. THIS IS USED TO LOCK TO PASSIVE MONUMENTATION IN THE PROJECT AREA.

  39. PROJECT SURFACE VS. GRIDIS YOUR DATA COLLECTOR CONFIGURED TO HANDLE THE TRANSFORMATION? • FEATURES AND WORK ARE REFERENCED TO THE GROUND • CONTROL MONUMENTATION IS USUALLY REFERENCED TO THE GRID • THERE ARE DIFFERENT WAYS TO RESOLVE THIS:1. MODIFIED SPC 2. LDP 3. LOCALIZATION TO PASSIVE MONUMENTATION4. ASSUMED (TANGENT PLANE)RTN CAN ENCOMPASS LARGE REGIONS COMPOSSED OF MANY STATES!

  40. EXAMPLE 1 DATA COLLECTORS MUST HAVE CORRECT PROJECTION PARAMETERS- EG., UTM, SPC, LDP, ASSUMED

  41. EXAMPLE 2 MESA COUNTY RTN & LOCAL COORDINATE ZONES

  42. LOYOLA SPATIAL SYSTEMS- RTKNET WILL OVERLAPPING RTN PRODUCE THE SAME COORDINATES?

  43. KEYSTONE - KEYNET

  44. CARON EAST -

  45. WHAT ABOUT GLONASS? NO OBSTRUCTIONS

  46. Dilution Of Precision - DOP

  47. NHUN-DOP/ NO OBSTRUCTIONS

  48. NHUN – SATELLITES/ WITH OBSTRUCTIONS

More Related