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Geomatics (CE304) (2-1-2-4-3) Course Evaluation Plan PERCENTAGE Lab Report with VIVA 30% Mid-Semester Exam 20% 2 Class Tests (one before Mid-term 10% (5% each) & one before End-term) E...

Geomatics (CE304) (2-1-2-4-3) Course Evaluation Plan PERCENTAGE Lab Report with VIVA 30% Mid-Semester Exam 20% 2 Class Tests (one before Mid-term 10% (5% each) & one before End-term) End-Semester Exam 40% Course contents 1. Introduction to Geomatics (2 Lecture + 0 Lab Hours): History of Surveying and Mapping, Importance of Geomatics Engineering, Maps and Maps Numbering System. 2. Concept of Datum and Map Projection System (3 Lecture + 2 Lab Hours): Coordinate System in Two and Three Dimensions, Datums, Geodetic Coordinate System, Coordinate Transformation, and Map Projection Systems. 3. Conventional Field Survey (4 Lecture + 2 Lab Hours): Introduction to Conventional Surveying Instruments and their Working Principles. The concept of Distance and Angular Measurements in Surveying. Sources of Errors in Conventional Surveying. 4. Modern Field Survey Systems (6 Lecture + 8 Lab Hours): Introduction and Development in the field of surveying. Working Principles of Instruments - Total Station, Global Positioning Systems, LASER based instruments. Sources of Error in the Measurements and their removal. 5. Space Technology for Surveying (8 Lecture + 8 Lab Hours): Remote Sensing and Photogrammetry - Fundamentals. Types of Photographs, Stereoscopy, Geometry of Photographs, Concept of Relief and Tilt Displacements, Digital Photogrammetry, Digital Image Processing. 6. Geographic Information System (3 Lecture + 4 Lab Hours): Introduction to Geographic Information System, Types of Data, Generation of Database, Concepts of Digital Maps, Integration of Information and Analysis. 7. Applications of Geomatics Engineering (2 Lecture + 4 Lab Hours): Topographic Mapping, Digital elevation models, Deformation Studies, Engineering Surveys, Land Use and Land Cover Mapping. Practical 1. Introduction to the traditional surveying instruments and measurement techniques. 2. Surveying using total station: Establishment of reference and collection of data using different methods, corrections and preparation of deliverables. 3. GPS survey for mapping and other engineering applications. 4. Introduction to satellite data and practical digital photogrammetry. 5. Preparation of base map for engineering sites in GIS environment. 6. Site suitability analysis using geomatics techniques. Suggested texts and reference materials 1. Arora, M. K. and Badjatia, R. C, Introduction to Geomatics Engineering, Nem Chand & Bros., Roorkee, India. (2011). 2. Duggal, S. K., "Surveying", Vol. I and II, McGraw Hill publication, Third Edition (2011). 3. Lillesand, T.L., and Kiefer, R.W., “Remote Sensing and Image Interpretation”, 4th Ed., John Wiley and Sons. (2005) Introduction to Geomatics The term ‘Geoinformatics’ a modern discipline, which integrates acquisition, modelling, analysis, and management of information about the natural environment and man-made structures with some established reference. Introduction to Geomatics  History of Surveying Role 2900 B.C. / Egypt For Great Pyramids 1400 B.C./ Egypt/China/India Land Division for Taxation 120 B.C. Diopter was developed for land survey 1570 A.D. First book on Surveying/Theodolite 1631 A.D. Vernier Theodolite 1800 A.D. More instrument were developed/ Concept of Plane and geodetic survey 1879 USGS was established 1931 Aerial Photogrammetry started which lead to development of Modern surveying. After 1980 use of GPS and other electronic devices started. Introduction to Geomatics Introduction to Geomatics Classification of Surveying Primary Classification Secondary Classification 1. Plane surveying 1. Based on Chain Survey instrument Compass survey Curvature of the earth is not Plane table survey taken into account. Theodolite survey Total station Survey Photographic survey 2. Geodetic surveying 2. Based on Triangulation survey methods Traverse survey Curvature of the earth is taken 3. Based on Topographic survey Land into account. purpose of the Geological survey surveying survey Mine survey Archeological Engineering survey survey Military survey Control surveying 4. Based on Land Survey nature of field Marine survey Astronomical survey Steel tape Chain Level ( stadia principle ) Total station Theodolite GPS Introduction to Geomatics Introduction to Geomatics Introduction to Geomatics Introduction to Geomatics Introduction to Geomatics Remote sensing the science and technique of acquisition of information without coming in contact with the any natural or man-made structures. It has three major divisions: Ground based remote sensing Aerial remote sensing Satellite remote sensing Ground based remote sensing Aerial remote sensing Satellite remote sensing Introduction to Geomatics Introduction to Geomatics  Navigation System There are 32 satellites in the GPS constellation, 31 of which are in use. Most common navigation and positioning system is Navstar GPS. Other systems are GLONASS, Galileo, Beidou, IRNSS (NAVIC) and QZSS Geographic Information System (GIS) GIS is a system designed to capture, store, manipulate, analyze, manage, and present spatial or geographical data. GIS applications are tools that allow users to create interactive queries (user-created searches), analyze spatial information, edit data in maps, and present the results of all these operations.  Google Maps, Google Earth and Bhuvan are the best examples of everyday used GIS system. A GIS system Showing IIT Ropar and places nearby (Google Maps) Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Surveying Maps What is Map? A map is a 2D representation of the 3D space. It can be defined as two dimensional representation of features present on or below the earth surface at a certain scale using symbols or/and colours schemes.  Elements or essential components of map includes: Projection Scale Legend Title of the map Symbolism Attributes Location map showing Lahul-Spiti valley. Example:  The scale here means 1 cm on a map is equal to 250 m on ground or 25000 cm on ground, therefore, RF for same is 1/25000.  Note: Larger is the denominator of the RF smaller is the scale.  For example: If the scale of the map is 1:10000 Smallest object which can be plotted in a map is.25 x 10000 mm or 2500 mm or 2.5 m. Note: Important features which are smaller in size than the minimum plotting accuracy are represented by proper symbols and colors. Map Numbering System To cover a large country or the world many map sheets will be required. For indexing the large volume of map sheets a proper naming or numbering scheme must be adopted so as to facilitate the user for referencing and cataloguing. I and AC Series SOI Map Numbering System India and Adjacent Country Series (I and AC Series) International map of the World Series or Carte International-du- Monde series) or CIM series. All base maps are in 1:1 Million Scale. These maps are further divided to large scale maps at the scale of 1:250,000, 1:50,000 and 1:25,000. I and AC Series Each 1: 1 M sheets covers 40 of latitude and 40 of longitude. Entire series covers a belt of 40 N latitude to 400 N latitude and from 440 E longitude to 1240 E longitude. India is covered in sheet no 39 to 92. I and AC Series 1:1,000,000 1:250,000 1:25,000 1:50,000 Ground Distance = (18 cm) / Scale CIM series CIM series Each sheet covers 40 of latitude and 60 of longitude. Sheets north of equator are prefixed N and that south of it by S. Each belt of 40 latitude starting from equator is labelled as A,B,C…..to V. Then, each belt of longitude starting from 1800 at 60 interval is numbered as 1,2,3,….till 60 in anticlockwise. 1:1,000,000 1:250,000 1:50,000 Coordinate System and Map Projections Where is my position? The position of any feature can be known only if we define a reference system. For making a map or to define a location it is important to define the position of any feature with a common frame of reference. This frame of reference is called coordinate system.  The coordinate systems that constitute the frames of reference allow us to specify position in terms of the distances or directions from fixed points, lines or surfaces. It is required for mapping, searching and indexing geographical information. Types The coordinate systems are of two type and are selected based on the type of survey. 1. Two dimensional coordinate systems. 2. Three dimensional coordinate systems. Two Dimensional Coordinate Systems  There are two plane coordinate systems: i. Rectangular coordinate system. ii. Polar coordinate system. It is used during the plane survey. It is a local coordinate system i.e. defined for a specific work. Rectangular Coordinate System  Defined by intersection of two straight lines called X and Y axes.  The point of intersection is know as origin (O).  x and y distance from origin is together know as x and y coordinates. Polar Coordinate System  Location of any point is given by distance and angle from a fixed point or origin subtended by a fixed line.  Origin (O) is known as pole.  Line OX is fixed line and is referred as polar axis. ᵨ is radius vector and angle ᶿ is taken + ve in anticlockwise direction.  The polar coordinates can be transformed to rectangular coordinates and vice versa. Three Dimensional Coordinate Systems  2D coordinate system define the position of a point in a plane surface but to represent any point in a space we need three dimensional coordinate system. There are two coordinate systems: i. Rectangular coordinate system. ii. Spherical coordinate system. Rectangular Coordinate System  Defined by intersection of three coordinate axes x, y and z or three coordinate planes.  The point of intersection is know as origin (O). Spherical Coordinate System Defined by:  Length of radius vector ρ.  The angle φ which the radius vector makes with X-Y plane.  The angle λ from the projection of radius vector on X-Y plane to x axis.  It can also be converted to rectangular coordinates as X= ρ cos φ cos λ Y= ρ cos φ sin λ Z= ρ sin φ  Now, here in the spherical coordinate system we have seen that the coordinates of any point is defined in term of the radius vector. This is by considering the earth as a sphere. But is the earth really sphere? If no, than this radius vector would be different at every place and the calculation for distance and height would be almost impossible to do. So what do we do now? We define a surface which could be used to compute all coordinates. Highest spot on earth?  Which is the tallest peak on earth? Mount Everest, at 8,850 meters above MSL  Which is the highest spot on earth where you are the closest to the outer space? Mount Chimborazo, in the Andes, 6,100 meters above MSL which is sitting on a bulge making it 2,400 meters taller than Everest. Everest is sitting down on the lower side of the same bulge. Datum It is the reference surface which is used for defining the coordinates. Since the earth is not a perfect sphere due to the terrain undulations reference surfaces are needed to define all coordinates (i.e. x, y and z). Shape of the Earth- Oblate spheroid We think of the... when it is actually an earth as a sphere... ellipsoid/Spheroid, slightly larger in radius at the equator than at the poles. Type of Datum To define x and y coordinates we need a surface which can be mathematically modelled such as an ellipsoid/spheroid. But is it sufficient to measure elevation? NO Why? As the earth's surface is not perfectly symmetrical, so the semi-major and semi-minor axes that fit one geographical region do not necessarily fit another. Therefore to define perfect location we need different ellipsoidal model.  Moreover, to define height as a constant value for a fixed object we needed something more. We also know that on the surface of earth water flows from higher elevation to lower elevation. Therefore, a surface to be flat or our reference plane we have to define a plane where the gravity is same at all points.  Can it be an ellipsoid or a spheroid. Yes if!! But there is a big ‘if’ in that. And what it is? The distribution of mass on earth surface. Our earth has different distribution of mass and the mass is responsible for the gravity. So when we define a surface which is equipotential in gravity it will not be a perfect ellipsoid or a spheroid. This surface is know as Geoid. A Geoid A Geoid as you see is am irregular surface so it is not mathematically definable. For a position to be fixed we need to define x and y coordinate which is mathematically definable. Type of Datum Therefore we need two datum: Horizontal Datum (Ellipsoid): To define location i.e. x and y coordinates. Vertical Datum (Geoid): To define z coordinates of any location. Horizontal Datum To define a horizontal datum we need eight parameters: i. Three parameters to represent origin of the coordinate system. ii. Three parameters to specify orientation of the coordinate system. iii. Two parameters to represent the reference ellipsoid. An ellipsoid is defined by two quantities, flattening (f) and eccentricity (e). Where a is the semi-major axis and b is the semi-minor axis of the ellipsoid. In astronomy reference ellipsoid is represented by the semi-major axis (a) and inverse of flattening (1/f). Vertical Datum The geoid (best approximate sea level) is our vertical datum. The relationship between the geoidal height (orthometic height; H) and the ellipsoidal height (h) is shown in the figure. H= h-N Deviations (undulations) between the Geoid and the WGS84 ellipsoid Projections Projected Coordinate System 2D representation of Earth based on some projection. Real-world features must be projected with minimum distortion from a round earth to a flat map; and given a grid system of coordinates. A map projection transforms latitude and longitude locations to x, y coordinates. What is a Projection? Mathematical transformation of 3D objects in a 2D space with minimal distortion. This two-dimensional surface would be the basis for your map. Types of Projections Conic (Albers Equal Area, Lambert Conformal Conic) - good for East- West land areas. Cylindrical (Transverse Mercator) - good for North-South land areas Azimuthal (Lambert Azimuthal Equal Area) - good for global views  Normal Transverse Oblique Azimuthal Cylindrical Conical Map Distortions Shape (conformal) - If a map preserves shape, then feature outlines (like country boundaries) look the same on the map as they do on the earth. Area (equal-area) - If a map preserves area, then the size of a feature on a map is the same relative to its size on the earth. On an equal-area map each country would take up the same percentage of map space that actual country takes up on the earth. Distance (equidistant) - An equidistant map is one that preserves true scale for all straight lines passing through a single, specified point. If a line from a to b on a map is the same distance that it is on the earth, then the map line has true scale. No map has true scale everywhere. Direction/Azimuth (azimuthal) – An azimuthal projection is one that preserves direction for all straight lines passing through a single, specified point. No map has true direction everywhere. Universal Transverse Mercator (UTM)  Universal Transverse Mercator (UTM) Uses the Transverse Mercator projection. 60 six-degree-wide zones cover the earth from East to West starting at 180° West. Extending from 80 degrees South latitude to 84 degrees North latitude. Each zone has a Central Meridian (λ). Reference Latitude (φ) is the equator. Units are meters.