1. Advance Surveying Equipments RAGC Dahanu

2. Modern equipments EDM Electronic distance measurement eqp. Auto level. Digital level. Total station. GPS global positioning system. 3. EDM Now separate EDM are not very popular , instead Total Station which have in built EDM is being used . Measurement of distance is accomplished with a modulated microwave or infrared carrier signal, generated by a small solid-state emitter within the instrument's optical path, and bounced off of the object to be measured. The modulation pattern in the returning signal is read and interpreted by the onboard computer in the EDM. The distance is determined by emitting and receiving multiple frequencies, and determining the integer number of wavelengths to the target for each frequency. 4. Hand held EDM Very handy, Cheap, Can be used with accuracy of 10mm or so, Useful for remote measurements like contact wire etc., 5. AUTO LEVEL Now most commonly used levelling instruments are - Auto level. Auto level, as name sounds it has a auto level compensator and corrects automatically if instrument goes out of level within its range. 6. With auto level:- Survey work can be done fast, Less chances of error, Magnification available is more, Range is more, Image is erect so less chances of error. 7. Digital level They are not popular instead auto levels are more extensively used. The Trimble DiNi Digital Level : Determine accurate height information 60% faster than with automatic leveling Eliminate errors and reduce rework with digital readings Transfer data to the office easily Measure to a field of just 30 cm 8. DIGITAL LEVEL Recently electronic digital levels have evolved as a result of development in electronics and digital image processing. Digital levels use electronic image processing to evaluate the special bar-coded staff reading. This bar-coded pattern is converted into elevation and distance values using a digital image matching procedure within the instrument. 9. SALIENT FEATURES OF DIGITAL LEVEL Fatigue-free observation as visual staff reading by the observer is not required. User friendly menus with easy to read, digital display of results. Measurement of consistent precision and reliability due to automation. Automatic data storage eliminates booking and its associated errors. 10. Fast, economic surveys resulting in saving in time (up to 50% less effort has been claimed by manufacturers). Data on the storage medium of the level can be downloaded to a computer enabling quick data reduction for various purposes. 11. COMPONENTS OF DIGITAL LEVEL The following discussion on digital levels has been primarily taken from Schoffield (2002). Main components of digital level consist of two parts: Hardware (Digital level and levelling staff) and Software. Both digital level and associated staff are manufactured so that they can be used for both conventional and digital operations. 12. Typically digital level has the same optical and mechanical components as a normal automatic level. However, for the purpose of electronic staff reading a beam splitter is incorporated which transfers the bar code image to a detector diode array. The light, reflected from the white elements only of the bar code, is divided into infrared and visible light components by the beam splitter. 13. The visible light passes on to the observer, the infrared to diode array. The acquired bar code image is converted into an analogous video signal, which is then compared with a stored reference code within the instrument. 14. Various capabilities of digital levels are as follows: 1. measuring elevation. 2. measuring height difference. 3. measuring height difference with multiple instrument positions. 4. levelling 6. setting out with horizontal distance 7. levelling of ceilings 15. PRINCIPLE OF EDMI The general principle involves sending a modulated Electro-magnetic (EM) beam from one transmitter at the master station to a reflector at the remote station and receiving it back at the master station. The instrument measures slope distance between transmitter and receiver by modulating the continuous carrier wave at different frequencies, and then measuring the phase difference at the master station between the outgoing and the incoming signals. This establishes the following relationship for a double distance (2D): 16. The following photographs show different types of EDMIs. 17. OPERATION WITH EDMI Measurement with EDMI involves four basic steps: (a) Set up (b) Aim (c) Measure (d) Record Setting up: The instrument is centered over a station by means of tribrach. Reflector prisms are set over the remote station on tribrach. 18. Aiming: The instrument is aimed at prisms by using sighting devices or theodolite telescope. Slow motion screws are used to intersect the prism centre. Some kind of electronic sound or beeping signal helps the user to indicate the status of centering. Measurement: The operator presses the measure button to record the slope distance which is displayed on LCD panel. Recording: The information on LCD panel can be recorded manually or automatically. All meteorological parameters are also recorded. 19. ERROR IN MEASUREMENT WITH EDMI 1. Instrument errors : centering at the master and slave station. pointing/sighting of reflector. entry of correct values of prevailing atmospheric conditions. 20. 2. Atmospheric errors : Meteorological conditions (temperature, pressure, humidity, etc.) have to be taken into account to correct for the systematic error arising due to this. These errors can be removed by applying an appropriate atmospheric correction model that takes care of different meteorological parameters from the standard one. 3. Instrumental error : Consists of three components - scale error, zero error and cyclic error. These are systematic in nature 21. TOTAL STATION Basic Principle A total station integrates the functions of a theodolite for measuring angles, an EDM for measuring distances, digital data and a data recorder. Examples of total stations are the Sokkia Set4C and the Geodimeter 400 series. All total stations have similar constructional features regardless of their age or level of technology, and all perform basically the same functions. 22. Features:- Total solution for surveying work, Most accurate and user friendly, Gives position of a point (x, y and z) w. r. t. known point (base point), EDM is fitted inside the telescope, Digital display, 23. On board memory to store data, Compatibility with computers, Measures distance and angles and displays coordinates, Auto level compensator is available, Can work in lesser visibility also, Can measure distances even without prismatic target for lesser distances, Is water proof, On board software are available, Can be used for curve layout after feeding data. 24. USES:- Total Stations can be used for: General purpose angle measurement General purpose distance measurement Provision of control surveys Contour and detail mapping Setting out and construction work 25. STORAGE Most TS have on-board storage of records using PCMCIA memory cards of different capacity. The card memory unit can be connected to any external computer or to a special card reader for data transfer. The observations can also be downloaded directly into intelligent electronic data loggers. Both systems can be used in reverse to load information into the instruments. Some instruments and/or data loggers can be interfaced directly with a computer for immediate processing and plotting of the data (Kavanagh, 2003). 26. FIELD OPERATION WITH TS Various field operations in TS are in the form of wide variety of programs integrated with microprocessor and implemented with the help of data collector. All these programs need that the instrument station and at least one reference station be identified so that all subsequent stations can be identified in terms of (X, Y, Z). Typical programs include the following functions: 27. Point location Missing line measurement (MLM) Resection Remote distance and elevation measurement Offset measurements Layout or setting out operation Area computation For details on above functions, one can refer to the user manual of any TS. 28. Different Types of TS and accessories Trimble(5600IR) 29. Factors influencing the use of Total Stations: A clear line of sight between the instrument and the measured points is essential. The precision of the instrument is dependent on the raw repeatabilities of the direction and distance measurements. A well defined measurement point or target/prism is required to obtain optimal precision and accuracy. The accuracy of direction and distance measurement is subject to a number of instrumental errors and the correct field procedures. 30. Auxiliary Equipment Required Targets or Prisms to accurately define the target point of a direction measurement. A data recorder if one is not integrated into the total station. A download cable and software on a PC to capture and process the captured digital data to produce contour and detail maps. 31. ROBOTICTS Display at target also, No need of operator on station, Moves automatically to predetermined direction and focuses automatically at target at specified distance, Can be integrated with GPS also. 32. REMOTE SENSING Science and art of obtaining information about an object, area, or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under investigation 33. REMOTE SENSING SYESTEM A typical remote sensing system consists of the following sub-systems: (a) scene (b) sensor (c) processing (ground) segment Various stages in these sub-systems are indicated in the next figure. The electro-magnetic (EM) energy forms the fundamental component of a RS system 34. APPLICATION OF REMOTE SENSING Agriculture:- Crop condition assessment. Crop yield estimation Urban Planning:- Infrastructure mapping. Land use change detection. Future urban expansion planning 35. Hydrology Forestry And Ecosystem Ocean applications Disaster management 36. IN CYCLONE: MITIGATION PREPAREDNESS RESCUE RECOVERY SATELLITES USED: Risk modelling; vulnerability analysis. Early warning; long-range climate modelling Identifying escape routes; crisis mapping; impact assessment; cyclone monitoring; storm surge predictions. Damage assessment; spatial planning. KALPANA-1; INSAT-3A; QuikScat radar; Meteosat Cyclone Lehar by KALPANA 1 Cyclone Helen by Mangalayan Example: 37. IN EARTHQUAKES: MITIGATION PREPAREDNESS RESCUE RECOVERY SATELLITES USED Building stock assessment; hazard mapping. Measuring strain accumulation. Planning routes for search and rescue; damage assessment; evacuation planning; deformation mapping. Damage assessment; identifying sites for rehabilitation. PALSAR; IKONOS 2; InSAR; SPOT; IRS The World Agency of Planetary Monitoring and Earthquake Risk Reduction (WAPMERR) uses remote sensing to improve knowledge of building stocks for example the number and height of buildings. High resolution imagery can also help hazard mapping to guide building codes and disaster preparedness strategies. 38. IN FLOODS: MITIGATION PREPAREDNESS RESCUE RECOVERY SATELLITES USED Mapping flood-prone areas; delineating flood-plains; land-use mapping. Flood detection; early warning; rainfall mapping. Flood mapping; evacuation planning; damage assessment. Damage assessment; spatial planning. Tropical Rainfall Monitoring Mission; AMSR-E; KALPANA I; Sentinel Asia a team of 51 organisations from 18 countries delivers remote sensing data via the Internet as easy-to-interpret information for both early warning and flood damage assessment across Asia. It uses the Dartmouth Flood Observatory's (DFO's) River Watch flood detection and measurement system, based on AMSR-E data, to map flood hazards and warn disaster managers and residents in flood-prone areas when rivers are likely to burst their banks. Flood In Uttarakhand Flood In Assam 39. IN OTHER DISASTERS: DISASTER MITIGATION PREPAREDNESS RECOVERY RESCUE SATELLITES USED DROUGHT Risk modelling; vulnerability analysis; land and water management planning. Weather forecasting; vegetation monitoring; crop water requirement mapping; early warning. Monitoring vegetation; damage assessment. Informing drought mitigation. FEWS NET; AVHRR; MODIS; SPOT VOLCANO Risk modelling; hazard mapping; digital elevation models. Emissions monitoring; thermal alerts. Mapping lava flows; evacuation planning. Damage assessment; spatial planning. MODIS and AVHRR; Hyperion FIRE Mapping fire-prone areas; monitoring fuel load; risk modelling. Fire detection; predicting spread/direction of fire; early warning. Coordinating fire fighting efforts. Damage assessment. MODIS; SERVIR; Sentinel Asia; AFIS LANDSLIDE Risk modelling; hazard mapping; digital elevation models. Monitoring rainfall and slope stability. Mapping affected areas; Damage assessment; spatial planning; suggesting management practices. PALSAR; IKONOS 2; InSAR; SPOT; IRS 40. 8th October 10th October 11th October 7th October, 2013: Indian Meteorological Department received information from KALPANA I, OCEANSAT and INSAT 3A Doppler radars deployed at vulnerable places, with over- lap, sensors in the sea and through the ships, about a cyclone forming in the gulf between Andaman Nicobar and Thailand named PHAILIN. 12th October 41. 8th October, 2013: IMD confirmed cyclone formation and predicted it as severe cyclone and its effects would be felt from Kalingapatnam in Andhra Pradesh to Paradeep in Odisha, and that it would probably first strikethe port of Gopalpur in Ganjam district at about 5 pm on 12 October. The wind speed could touch 200(km/h). 10th October, 2013: IMD prediction of a severe cyclone was converted to a very severe cyclonic storm with wind speeds up to 220 kmph. the US Navys Joint Typhoon Warning Centre predicted it would have wind speeds up to 315 km/h. 12th October, 2013: The very severe cyclonic storm had its landfall at Gopalpur port at about 9 pm with a wind speed of 200 km/h. 42. What is GPS? The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. A global navigation satellite system consisting of positioning satellites and their associated ground stations. The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the US government and is freely accessible to anyone with a GPS receiver. 43. Development of GPS The GPS project was developed in 1973 to overcome the limitations of previous navigation systems, integrating ideas from several predecessors, including a number of classified engineering design studies from the 1960s. GPS was created and realized by the U.S. Department of Defense (DoD) and was originally run with 24 satellites. It became fully operational in 1995. Bradford Parkinson, Roger L. Easton, and Ivan A. Getting are credited with inventing it. Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS system and implement the next generation of GPS III satellites and Next Generation Operational Control System (OCX). Announcements from Vice President Al Gore and the White House in 1998 initiated these changes. In 2000, the U.S. Congress authorized the modernization effort, GPS III. In addition to GPS, other systems are in use or under development. The Russian Global Navigation Satellite System (GLONASS) was developed contemporaneously with GPS, but suffered from incomplete coverage of the globe until the mid-2000s. There are also the planned European Union Galileo positioning system, Chinese Compass navigation system, and Indian Regional Navigational Satellite System. 44. BASICs of GPS? Satellites are placed in Medium Earth Orbit (MEO) at an altitude of 12,552 miles Orbital periods of MEO satellites range from 2 - 12 hrs. Orbital period of GPS satellites is 12 hours (2 rotations/day) GPS Satellites travel at a speed of 7,000 mph Orbits are arranged so that at any time, anywhere on Earth, at least four satellites are visible in the sky 45. Orbiting Satellite A visual example of a 24 satellite GPS constellation in motion with the Earth rotating. About nine satellites are visible from any point on the ground at any one time, ensuring considerable redundancy over the minimum four satellites needed for a position. 46. Basic concept of GPS A GPS receiver calculates its position by precisely timing the signals sent by GPS satellites high above the Earth. Each satellite continually transmits messages that include- the time the message was transmitted satellite position at time of message transmission Differential time of arrival and triangulation are the methods used to determine location in a GPS system. 47. Differential Time of Arrival: Differential time of arrival is the method used to determine how far each satellite is from a GPS device. Although each satellite transmits its position and the time it was at that position, it takes time for that signal to reach the Earth. The receiver contains a very accurate clock, which can determine the difference in time between the current time and when the satellite sent the signal. With this differential time and the speed of radio waves, the distance from each of the three satellites can be determined using the simple formula: Rate x Time = Distance 48. Composition of Receivers GPS receivers are composed of an antenna, tuned to the frequencies transmitted by the satellites, receiver-processors, and a highly stable clock (often a crystal oscillator). They may also include a display for providing location and speed information to the user. A receiver is often described by its number of channels: this signifies how many satellites it can monitor simultaneously. Originally limited to four or five, this has progressively increased over the years so that, as of 2007, receivers typically have between 12 and 20 channels. 49. Application of GPS While originally a military project, GPS is considered a dual-use technology, meaning it has significant military and civilian applications. GPS has become a widely deployed and useful tool for commerce, scientific uses, tracking, and surveillance. GPS's accurate time facilitates everyday activities such as banking, mobile phone operations, and even the control of power grids by allowing well synchronized hand-off switching. 50. Contd Disaster relief/emergency services: depend upon GPS for location and timing capabilities. Meteorology-Upper Airs: measure and calculate the atmospheric pressure, wind speed and direction up to 27 km from the earth's surface Fleet Tracking: the use of GPS technology to identify, locate and maintain contact reports with one or more fleet vehicles in real-time. Geofencing: vehicle tracking systems, person tracking systems, and pet tracking systems use GPS to locate a vehicle, person, or pet. These devices are attached to the vehicle, person, or the pet collar. The application provides continuous tracking and mobile or Internet updates should the target leave a designated area.[72] Geotagging: applying location coordinates to digital objects such as photographs (in exif data) and other documents for purposes such as creating map overlays with devices like Nikon GP-1 51. Contd GPS Aircraft Tracking GPS for Mining: the use of RTK GPS has significantly improved several mining operations such as drilling, shoveling, vehicle tracking, and surveying. RTK GPS provides centimeter-level positioning accuracy. GPS tours: location determines what content to display; for instance, information about an approaching point of interest. Navigation: navigators value digitally precise velocity and orientation measurements. Phasor measurements: GPS enables highly accurate timestamping of power system measurements, making it possible to compute phasors. Recreation: for example, geocaching, geodashing, GPS drawing and waymarking. Robotics: self-navigating, autonomous robots using a GPS sensors, which calculate latitude, longitude, time, speed, and heading. Surveying: surveyors use absolute locations to make maps and determine property boundaries. Tectonics: GPS enables direct fault motion measurement in earthquakes. Telematics: GPS technology integrated with computers and mobile communications technology in automotive navigation systems 52. Finding the Mystery Location Your GPS receiver has been pre-programmed (by your instructor) with a mystery location. Now let's explore how the GPS receiver can be used to navigate to an unknown location. Randomly choose three-to-five different locations on the grounds. These locations should be fairly distant from each other (at least 500 feet apart). Remember to choose locations where the GPS receiver will have a good view of the sky. 53. Proceed to Point No. 1. Record the following information in the data table below: Use the Position Page (graphic compass) to acquire your current position. Record your latitude and longitude. Press the GOTO key. The Navigation Page (graphic highway) will appear with the waypoint field highlighted. Press the up or down arrow keys to scroll through the available waypoints until "MYSLOC" (short for "mystery location") is displayed. Press the ENTER key to confirm that you want to navigate to "MYSLOC". Record the bearing (in degrees) and distance (in kilometers) to the mystery location. Briefly describe the location. 54. Repeat Steps 1-3 until you have visited at least three different locations on the grounds. Do not actually go to the mystery location! Field Data Point No. Latitude (deg. N) Longitude (deg. W) Bearing (deg.) Distance (km) Brief Description 1 2 3 4 5 55. Steps to find mystery location Using your Field Data for Point No. 1 (latitude, longitude, and distance), draw Circle 1. Technique Hint: Use latitude and longitude to locate Point 1 on the map; use the map scale to measure the radius of Circle 1; draw the circle. Using your Field Data for Point No. 2, draw Circle 2. Using your Field Data for Point No. 3, draw Circle 3. You would discover that there is one and only one point where all three circles intersect. 56. Yield Monitoring Systems Yield monitoring systems typically utilize a mass flow sensor for continuous measuring of the harvested weight of the crop. The sensor is normally located at the top of the clean grain elevator. As the grain is conveyed into the grain tank, it strikes the sensor and the amount of force applied to the sensor represents the recorded yield. While this is happening, the grain is being tested for moisture to adjust the yield value accordingly. At the same time, a sensor is detecting header position to determine whether yield data should be recorded. Header width is normally entered manually into the monitor and a GPS, radar, or a wheel rotation sensor is used to determine travel speed. The data is displayed on a monitor located in the combine cab and stored on a computer card for transfer to an office computer for analysis. Yield monitors require regular calibration to account for varying conditions, crops, and test weights. Yield monitoring systems cost approximately $3,000 to $4,000, excluding the cost of the GPS unit. How Is GPS Used in Farming? 57. Field Mapping with GPS and GIS GPS technology is used to locate and map regions of fields, such as high weed, disease, and pest infestations. Rocks, potholes, power lines, tree rows, broken drain tile, poorly drained regions, and other landmarks can also be recorded for future reference. GPS is used to locate and map soil-sampling locations, allowing growers to develop contour maps showing fertility variations throughout fields. The various datasets are added as map layers in geographic information system (GIS) computer programs. GIS programs are used to analyze and correlate information between GIS layers. 58. GPS technology is used to vary crop inputs throughout a field based on GIS maps or real-time sensing of crop conditions. Variable rate technology requires a GPS receiver, a computer controller, and a regulated drive mechanism mounted on the applicator. Crop input equipment, such as planters or chemical applicators, can be equipped to vary one or several products simultaneously. Variable rate technology (VRT) is used to vary fertilizer, seed, herbicide, fungicide, and insecticide rates and for adjusting irrigation applications. The cost of all of the components necessary for variable rate application of several products is approximately $15,000, not including the cost of the GPS receiver. Technology capable of varying just one product costs approximately $4,000. PRECISION CROP INPUT APPLICATIONS 59. DRAWBACK of GPS The drawback to current GPS units is that they cannot track positions inside of buildings or other places that shield signals coming from satellites.