Introduction to Control Network PDF

Geodetic Control Network  Introduction to Geodetic Control Network OUTLINE Definitions Components of a Geodetic Control Network History and Technological Advancement of...

Geodetic Control Network  Introduction to Geodetic Control Network OUTLINE Definitions Components of a Geodetic Control Network History and Technological Advancement of Geodetic Surveying International Frameworks and Geoid Models The Luzon Datum of 1911 and the Philippine Reference System (PRS92) Order, Accuracy Standards, and Specifications of Geodetic Control Network Monitoring and Maintaining the Geodetic Control Network Technical Manuals and Guidelines UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Geodetic Control Surveys performed to establish an accurate positional framework (i.e. geodetic control network) from which nationwide supplemental surveying and mapping are referred is the determination of the precise position of a number of stations distributed over an area, taking into account the curvature of the earth, to serve as primary reference or as check points for other subsequent surveys to be used in engineering projects UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Geodetic Control Surveys performed to far more rigorous accuracy and quality assurance standards than those for local control surveys (project control) distinguished by use of redundant, interconnected, permanently monumented control points used also to effectively and efficiently monitor and evaluate external deformations in large structures such as dams UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Relevance of Geodetic Network Tenure and value records Resources Other records Administrative Other parcel- records related records records related records Other Identifiers Parcel id Cadastral Other Data-exchange boundary overlays Conventions overlay Base maps GEODETIC REFERENCE FRAMEWORK Source: National Research Council 1980 UP Department of Geodetic Engineering GE 155: Geodetic Control Network Components of a Geodetic Control Network HORIZONTAL CONTROL provided by two or more points in the ground, permanently or semi-permanently monumented, and precisely fixed in position horizontally by distance and direction, or coordinates established by performing triangulation, trilateration, traversing, or by the use of GNSS UP Department of Geodetic Engineering GE 155: Geodetic Control Network Components of a Geodetic Control Network VERTICAL CONTROL provided by benchmarks in or near the track to be surveyed, and it becomes the basis for all elevations and in portraying the relief of the area usually established by running lines of differential levels GPS surveying may also be used, but elevations must be converted to orthometric heights first in order to be acceptable UP Department of Geodetic Engineering GE 155: Geodetic Control Network History of Geodetic Surveying HISTORY OF GEODETIC SURVEYING IN THE PHILIPPINES Americans took over the Philippines from the Spaniards 1898-1900 Discovered inaccurate maps and charts Appeal to have the island surveyed and charted Dec. 1900 CGSD was established in Manila Start of actual fieldwork, only in the vicinity of the garrisoned places Jan. 1901 UP Department of Geodetic Engineering GE 155: Geodetic Control Network History of Geodetic Surveying HISTORY OF GEODETIC SURVEYING IN THE PHILIPPINES System of military telegraph and cable lines used to establish a large number of astronomical stations well scattered throughout the islands The precise latitude and longitude 1901-1906 of these stations were determined, and eventually connected by a triangulation net More surveys to meet the demands of the military and the local commerce About 90 charts already produced UP Department of Geodetic Engineering GE 155: Geodetic Control Network History of Geodetic Surveying HISTORY OF GEODETIC SURVEYING IN THE PHILIPPINES Five vessels doing hydrographic and topographic surveys Computers and draftsmen sent to Manila office engaged in compiling charts from 1907 the new surveys About 153 catalogued charts produced First printing plant in Manila (all previous 1920 maps were printed in Washington) Until Expansion of surveys to whole Philippines 1942 UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Technological Advancement in Geodetic Control Establishment INTRUMENTATION Direction Theodolite Steel Measuring Bands Geodimeter UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Technological Advancement in Geodetic Control Establishment INTRUMENTATION Total Station Gravimeter GNSS UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Technological Advancement in Geodetic Control Establishment TRADITIONAL SURVEY POSITIONING TECHNIQUES Horizontal Positioning 1. Astronomical techniques 2. Triangulation 3. Trilateration 4. Traversing UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Technological Advancement in Geodetic Control Establishment TRADITIONAL SURVEY POSITIONING TECHNIQUES Vertical Positioning 1. Precise or geodetic leveling 2. Trigonometric leveling 3. Barometric leveling UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models WHY DO WE HAVE MANY FRAMEWORKS? ????? Numerous reference ellipsoids/datum Various geoid models Many countries Advancing technologies Global vs. Global Global vs. Local UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models The Global and the Local Geodetic Reference Frame Global Reference Frame Looking at the definition of a reference frame, there should be only one truly global reference frame Local Reference Frames Since each country/area in the surface of the earth uses a frame that is appropriate to the local surface, there are infinite number of local frames. UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models World Geodetic System of 1984 (WGS84) The WGS84 coordinate system is a conventional terrestrial reference system (CTRS) The definition of this coordinate system outlined by the International Earth Rotation Service (IERS) as follows: It is geocentric, the center of mass being defined for the whole earth including oceans and atmosphere. Its scale is that of the local earth frame Its orientation was given initially by BIH on 1984 UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models World Geodetic System of 1984 (WGS84) WGS84 is maintained by the US DoD for its military purposes It was initially established using different terrestrial and extraterrestrial positioning methods such as the Doppler systems The most recent WGS84 realization adopted by the US DoD is the WGS84 (G1150) UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models International Terrestrial Reference Framework (ITRF) The ITRF is established by the Terrestrial Reference Frame Section of the Central Bureau (CB) of the International Earth Rotation Service (IERS) The implementation of the ITRF is based on the combination of Sets of Station coordinates (SSC) and velocities derived from observations of space-geodetic techniques The global solutions are: ITRF88, 89, 90, 91, 92, 93, 94, 96, 97, 00, 05 , 08 UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models Relationship of ITRF and WGS84 WGS84 and ITRF94 are practically identical (with respect to its parameters and definition) The positions that can be derived from WGS84 and ITRF conforms up to about ±2 cm accuracy UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models Geoid Models: EGM Earth Gravitational Model Developed in a collaborative effort of: NASA Goddard Space Flight Center; National Imagery and Mapping Agency (NIMA); Ohio State University UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models Geoid Models: EGM predecessor models: OSU-91A model JGM-2 model based on: surface gravity data; altimeter-derived gravity anomalies; extensive satellite tracking data (GPS, TDRSS, DORIS, TRANET); direct altimeter ranges UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models Geoid Models: EGM EGM2008 This gravitational model is complete to spherical harmonic degree and order 2159, and contains additional coefficients extending to degree 2190 and order 2159 Can compute geoid undulations accurate to better than one meter Can be used with the WGS 84 reference ellipsoid using a set of pre- computed constants UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models Geoid Models: Others EGM96 Gpm3e97a (1997) GPM98A, B and C (1998) Other national geoid models UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models The Philippine Geoid Model Based on “The Evaluation of the Geoid in the Philippines” by A.H.W. Kearsley Part of the 1st order geodetic control survey component of the Natural Resources Management and Development Project (NRMDP) Describes the investigation into the detailed geoid for the Philippines UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models The Philippine Geoid Model Based on: Altimetrically-derived gravity data Terrestrially observed gravity data Gravity profiles in Northern Luzon (mountainous; 170 km) and Eastern Mindanao (flat; 75 km) Geopotential Models - OSU86 E and OSU89A DEM - ETOPO5 world data of 5’ mesh of heights - From digitized topographic maps of 1:250,000 scale by CERTEZA GPS Control over BM with known MSL Heights UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models The Philippine Geoid Model Problems with the data: Low density of gravity data Satellite altimeter data contains free-air anomalies over land areas Some observed terrestrial data over the oceans are in conflict with those from satellite altimetry Data file appears to contain large errors The gravity profiles and DEM show very little correlation hence no high-frequency information can be derived DEM was derived from a weak mathematical method and is not reliable for deriving terrain corrections Both OSU86E and OSU89A fit the terrain equally (and poorly) UP Department of Geodetic Engineering GE 155: Geodetic Control Network  International Frameworks and Geoid Models The Philippine Geoid Model Tests show that the geoid heights have a precision of better than 10ppm The gravimetric N against those from GPS/leveling identified a number of doubtful control stations which may be attributed to the errors in the orthometric heights Better solutions of N were derived using smaller ring sizes Certain biases exist for the N values near the gravity profiles UP Department of Geodetic Engineering GE 155: Geodetic Control Network International Frameworks and Geoid Models The Philippine Geoid Model UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 The Original Network Local datums were established at “Astro stations” that include Bancalan Island, Cagayan Sulu Island, Davao, Iligan, Misamis Oriental, and Zamboanga on Mindanao Island,Legaspi and Vigan on Luzon Island, Ormoc and Tacloban on Leyte Island and Iloilo on Panay Island. However, the extent of coverage became limited due to physical configuration of the country w/c rendered development of network especially inland not feasible by conventional surveying techniques. Stations were established along the coasts. UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Luzon Datum of 1911 Can be defined by the origin near San Andres point on Marinduque Island in the Southern Tagalog Region, stationed at Balanacan. Established in 1911 and is defined in terms of position of station Balanacan: Latitude= 13-33-41 Longitude= 121-52-03 Azimuth to Station Baltazar= 9-12-37 UP Department of Geodetic Engineering GE 155: Geodetic Control Network Luzon Datum Origin: Balanacan UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  Balanacan Station (May 2007) UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Luzon Datum of 1911 The reference ellipsoid used was Clarke Spheroid of 1866 where: a=6378206.4 m 1/f=294.9786982m The original survey was second order or lower, controlled by 98 measured base lines, 52 observed azimuths and 49 latitude and telegraphic longitude stations Geoid and ellipsoid were assumed to coincide at the datum origin, i.e., deflection of the vertical and geoid- ellipsoid separation were defined as zero UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 The Natural Resources Management and Development Project (NRMDP) The proliferation of geographic information projects necessitates the establishment of standards and coordination mechanisms in order to ensure compatibility of geographic information systems, facilitate data exchange, and optimize use of resources The NRMDP (1989-1992) of DENR recommended the use of National Statistical Coordination Board’s (NSCB) coordinative set up in addressing the problems besetting the system UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 The Natural Resources Management and Development Project (NRMDP) An Inter-Agency Task Force on Geographic Information was created to promote and coordinate the efficient development, management and utilization of geographic information in the country NAMRIA, NSCB, HLURB, NSO, NCC, DPWH, DOST, BSWM, NEDA 330 first-order stations, 101 second- order, 36 third-order UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 Established by NAMRIA in 1992 thru DENR-NRMDP in collaboration with the Government of Australia By law, it is the Philippines’ standard survey and mapping reference frame/system A set of coordinates of all stations in the new network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 PRS 92 is not a new datum but an adjustment of the Luzon datum The original datum observations from Luzon 1911, used in PRS 92, were not recomputed NAMRIA has published transformation parameters for PRS 92 to WGS 84 UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 The horizontal datum component was undertaken using GPS using the guidelines based on recognized Australian specifications and practices and standards of the Hydrography Department (then, CGSD) of NAMRIA A national geoid model for the vertical component was developed for the Philippines with relative accuracy of 5 ppm and 8 ppm based on OSU89 geoid model, supplemented by local gravity data, where gravity surveys were taken in Northern Luzon in San Fernando, La Union to Cauyan, Isabela and in eastern Mindanao in Surigao City UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Geodetic Control Network PHILIPPINE ACTIVE GEODETIC NETWORK (PageNET) the country’s new positioning infrastructure which utilizes signals from global navigation satellite systems (GNSS) a network of continuously operating reference stations that provide real-time, high-precision geographic position data via the Internet data generated by the network may be used for surveying and mapping, aviation, navigation, military, scientific research and monitoring, and agriculture, among others UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 modernization Further densification efforts by NAMRIA Zero-order network Issues: WGS84 refinement Effect of plate tectonics UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 Modernization WGS84(original) WGS84(G1150) UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 Philippine Reference System of 1992 Modernization WGS84 refinement WGS84 (original) → PRS92 WGS84 (G730) – 1994 WGS84 (G873) – 1996 WGS84 (G1150)- 2002 “G” – for GPS 730, 873, 1150 – number of weeks reckoned from date of GPS full implementation UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 The Philippine Geocentric Datum of 2020 Different datums give different coordinates UP Department of Geodetic Engineering GE 155: Geodetic Control Network  The Luzon Datum of 1911 and the PRS92 The Philippine Geocentric Datum of 2020 Effect of plate tectonics Philippine plate moving NW with velocity of 2-7mm per year (NIGS/Phivolcs) Effect on PRS92 GPS stations not monitored UP Department of Geodetic Engineering GE 155: Geodetic Control Network Thank you