INTRODUCTION TO TOTAL STATION & GLOBAL POSITIONING SYSTEM (GPS)

1. Presentation on MODERN SURVEYING INSTRUMENTS INTRODUCTION TO TOTAL STATION & GLOBAL POSITIONING SYSTEM (GPS)

2. Electronic Total Station (ETS)

3. Electronic Total Station The Total Stations are recent and most common types of electronic surveying instruments comprising of mainly an EDM, an EDT and a limited capability micro processor in a single compact and mobile unit which can be setup on tripod at field during survey to collect essential distance - direction data to define the positions of points with respect to each other.

4. What Is Total Station • COMBINATION OF EDT + EDM + Computer • ON BOARD MEMORY SYSTEM • INCLUDING DOWNLOAD & UPLOAD FACILITY • IN BUILT PROGRAMME FOR CO-ORDINATE • CALCULATION, AREA CALCULATION, • STAKE-OUT etc.

5. Principal Features Of ETS • Measures Direction & Distance Simultaneously • Effortless Levelling Through Electronic Digital Bubble • Effortless Centering Through Laser Plummet • Automatic Correction For Temperature, Pressure, Curvature and Refraction • Multi Axis Compensator • Data Storage Facility • Data Downloading and Uploading Facility • On Board Computer

6. Principal Features • Effortless Levelling Through Electronic Digital Bubble • Automatic Correction For • i) Temperature • ii) Pressure • iii) Curvature

7. WATER AND DUST RESISTANT The rain cannot come into the inside of the instrument in unexpected rainfall and it is specially designed for the bad site conditions the machine is completely dustproof

8. LUMI GUIDE OPERATION

9. REFLECTORLESS MEASUREMENT REMOTE CONTROL SYSTEM WITH THIS FEATURE YOU CAN DETERMINE POINTS AND MEASURE DISTANCES WITHOUT USEING ANY REFLECTOR.

10. TRI-AXIAL COMPENSATOR Tri axis compensator performs fine leveling and error which occurs where the vertical and horizontal axis intersect

11. AUTOMATIC ATMOSPHERE SENSOR The built in automatic atmospheric sensors, measures the temperature and pressure in real time, and initiates ppm correction .thus, the user no longer needs to bother with inputting these data

12. LASER PLUMMET The machine enables easy to center over a setup point thanks to the laser plummet. The intensity of the laser point can be adjusted step-by-step to maintain visibility even in critical lighting conditions

13. MEASUREMENT OF DISTANCES, DIRECTIONS AND ELEVATION

14. Basic Common Inbuilt Programmes • Reduction of co-ordinates • Area & Perimeter Calculation • Remote Elevation Measurement • Missing Line Measurements • Offset Measurements • Resection • COGO (Co-ordinate Geometry) • Setting Out

15. CARTESION & POLAR FRAME Of REFERANCE CARTESION Easting of p = r * Sin q Northing of p = r * Cos q POLAR p = r q

16. AREA MEASURMENT Area In sq.Mtr. And Hector

17. REMOTE ELEVATION MEASURMENT ent

18. MISSING LINE MEASURMENT

19. OFFSET MEASURMENT

20. RESECTION

21. Co-ordinate Geometry Line – Line Intersection Line – Circle Intersection Circle – Circle Intersection Reference Line Calculation Bearing & Distance Point & Point

22. SETTING OUT

23. ADVANTAGES OF USING TOTAL STATION • ACURACY IN DISTANCE MEASURMENTS AND • ANGLE MEASURMENTS • ELIMINATION OF MANUAL ERRORS • ELIMINATION OF MATHEMATICAL CALCULATION • GENERATION OF DATA IN DIGITAL FORMAT • ZERO PLOTTABLE ERROR • REDUCTION OF TIME AND COST • PROFESSIONAL OUTPUT AND QUALITY PRODUCT

24. NETWORK Total Station Survey Field Sketches Downloading Cad Drafting Digitisation of Records Superimposition Multi size and Multicolour Tracing / Paper output Digital Output Reports

25. DXF DATA RECEIVED FROM TOTAL STATION

26. DOWNLOADED DATA ALONGWITH DESCRIPTION AND POINT NUMBERS

27. PROCESSING OF DATA AND VECTERISATION USING AUTO-CAD SOFTWARE

28. DEVELOPMENT OF CO-ORDINATE SYSTEM ARBITARY CO-ORDINATES N-1000 , E-1000 TAKEN AT TRAVERSE STATION NO.1

29. FINAL OUTPUT INITIAL RAW DATA

30. GPS

31. Global Positioning System (GPS)

32. What is GPS? GPS is a space based all weather radio navigation system.

33. GPS Provides Position (geographic), Velocity & Time (PVT) Quickly, Economically And Precisely 24 hours a day, anywhere in the world under the sky

34. GPS Consists of Three Segments

35. Salient steps The receiver picks up the signals from the satellites; Uses signal travel time to calculate distance to the satellites Using Analytical Principle, position of the receiver gets calculated.

36. Space Segment Constellation of 24 navigational satellites. Four satellites are placed in each of six orbital planes with an inclination of about 55° to the equator. With this constellation 4 to 10 GPS satellites are always available above the horizon anywhere in the world.

37. Space segment • 24 satellites • Orbit every 12 hours at 20,200 kms • 4 satellites in each of 6 orbital planes • Transmit a uniquely coded radio signal • Equipped with onboard atomic standard

38. What is so special about an 20200 km orbit? • ‘Orbits’ twice per day • Large ‘viewable’ area

39. Control segment Worldwide network of tracking stations, with a master control station located in United States. The primary task of the control segment is to track GPS satellites in order to determine and predict some information and upload into the GPS satellite

40. Control segment • Ground-based monitoring and upload stations • Control orbit and timing information

41. USER • It includes all GPS users. User can receive the GPS signals through antenna connected to the receiver and can determine its position on the surface of the earth

42. User segment • GPS Receivers; • Compatible software for Planning, Downloading and Processing of GPS receiver data;

43. Navigation • capable of about 12 meter accuracy • light-weight, cheap! • navigation applications GPS Receivers (contd.)

44. Different modes of GPS positioning Point positioning It involves only one GPS receiver that simultaneously receives signals from at least four satellites to determine its own co-ordinates with respect to the center of the earth.

45. Differential positioning It is a relative positioning which involves two receivers, one called as a base and the other called as a rover, simultaneously tracking the same satellites to determine their relative co-ordinates. The base whose co-ordinates are known precisely remains stationary at a site and the rover may or may not be stationary

46. S2(x2,y2,z2) S1(x1,y1,z1) S3(x3,y3,z3) S4(x4,y4,z4) GPS Receiver (X,Y,Z) 1 = {(x1-x)2+(y1-y)2+(z1-z)2} + c.Δt 2 = {(x2-x)2+(y2-y)2+(z2-z)2} + c.Δt 3 = {(x3-x)2+(y3-y)2+(z3-z)2} + c.Δt 4 = {(x4-x)2+(y4-y)2+(z4-z)2} + c.Δt Principle of GPS Positioning

47. Positioning With Satellite • Satellites are reference points to locations on earth (their location are known) • A location of a point on earth is identified by “triangulation” • Travel time of each signal is determined • Signals travel at Speed of light • Distance = Travel Time * Speed of Light

48. RTK GPS This method is used when the co-ordinates of unknown points are to be known in real time The base receiver is attached to the radio transmitter. The rover which is normally carried in a backpack and also attached to the radio receiver. The co-ordinates and measurement data transmitted to the rover through the radio. The built-in software in a rover process the measurement collected at both the receivers to obtain it’s own co-ordinates.

49. Sea surface Ellipsoid Earth surface Geoid A smooth mathematical surface required approximating the irregular shape of the earth is called as reference surface. This reference ellipsoid is known as the geodetic datum. The World Geodetic System of 1984 (WGS 84) is an example of such geodetic datum.

50. Map ProjectionMap projection is defined as the transformation of geodetic co-ordinates (,) obtained from GPS in to rectangular co-ordinate system called as easting & northing.