GPS 4H: USING THE GLOBAL POSITIONING SYSTEM IN 4H PROGRAMMING MIKE CLIFFORD

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GPS 4-HUSING THE GLOBAL POSITIONING SYSTEM IN
4-H PROGRAMMING MIKE CLIFFORD
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GPS WOULD HAVE SAVED HIM !!!
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Global Positioning System A network of
satellites that continuously transmit coded
information, which makes it possible to precisely
identify locations on earth by measuring distance
from the satellites.
THE GPS SATELLITE CONSTELLATION
From GPS Land Navigation by Michael Ferguson
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GPS and GIS DEFINITIONS
GPS is short for Global Positioning System is a
satellite system used to navigate. It enables
anyone on the planet who owns a GPS receiver to
know where they are 24 hours a day in any kind of
weather. GIS is short for Geographic Information
System(s). "In the strictest sense, a GIS is a
computer system capable of assembling, storing,
manipulating, and displaying geographically
referenced information , i.e. data identified
according to their locations. Practitioners also
regard the total GIS as including operating
personnel and the data that go into the system"
( from http//www.usgs.gov/research/gis/title.ht
ml ).
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The NAVSTAR System
24 Satellites 6 orbital plates 11,000
miles up 12 hour orbit
from GPS Land Navigation by Michael Ferguson
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THE EARTH Latitude Longitude
from GPS Land Navigation by Michael Ferguson
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ERROR SOURCES Multipath interference
Atmospheric Geometric DOP
Clock Ephemeris
S.A. (now turned off)
LINE OF SIGHT
from GPS Land Navigation by Michael Ferguson
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ACCURACY
STANDARD CIVILIAN RECEIVERS
(Selective Availability OFF)
HORIZONTAL ACCURACY TO 15 METERS (49.2) OR BETTER
VERTICAL ACCURACY (altitude) TO 100 METERS (328)
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WIDE AREA AUGMENTATION SYSTEM
WAAS is a collection of ground stations that use
differential GPS techniques to calculate the
amount of error in the GPS signals. With WAAS
enabled, GPS units are accurate within 3 m
horizontal and 6 m vertical compared to 15 m
horizontal and 19 m vertical without WAAS.
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Orange Without WAAS enabled Blue With WAAS
enabled
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SOME GPS APPLICATIONS
COMMERCE GOVERNMENT
RECREATIONAL

• HIKING
• HUNTING
• NATURE STUDY
• FISHING
• BOATING
• BIKING
• SKIING
• SNOWMOBILING
• GEOCACHING
• GOLF ! ETC.

• MILITARY
• MARITIME
• AUTOMOTIVE
• SURVEYING
• AVIATION
• FORESTRY
• ENVIRONMENTAL
• PUBLIC SAFETY
• ETC.

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HOW CAN WE UTILIZE GPS IN 4-H PROGRAMMING?
EDUCATIONAL OPERATIONAL USES
WILDLIFE MAPPING
HIGH ADVENTURE
LEADER TRAINING
SEARCH RESCUE
BIG TREE SEARCH
SCIENCE TECHNOLOGY
HUNTER EDUCATION
TRIP PLANNING SAFETY
FISHING CANOEING
ENVIRONMENTAL EDUCATION
AND LOTS MORE !
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NAVIGATION BASICS

• 1. KNOW YOUR POSITION
• 2. PLAN YOUR ROUTE
• 3. STAY ON YOUR ROUTE
• 4. RECOGNIZE YOUR DESTINATION

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• BASIC NAVIGATION INFORMATION
• PROVIDED BY GPS UNITS . . .
• YOUR CURRENT POSITION
• COORDINATES (LATITUDE LONGITUDE, UTM, MGRS,
  ETC.)
• ELEVATION (0R BETWEEN WAYPOINTS)
• DIRECTION TO SPECIFIED WAYPOINTS
• DISTANCE TO SPECIFIED WAYPOINTS
• (0R BETWEEN WAYPOINTS
• YOUR SPEED OF TRAVEL
• YOUR DIRECTION OF TRAVEL

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. . . AND OFTEN MUCH MORE MAPS TIME OF
DAY CROSS TRACK ERROR ESTIMATED TIME OF
ARRIVAL ESTIMATED TIME ENROUTE COORDINATES OF
CITIES TOWNS ETC.
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Map Datum

• Maps are drawn so every point is a known distance
  and height from a standard reference point called
  a datum. A grid is a series of lines on a map
  that helps you describe a location in reference
  to the datum.
• WGS84 World Geodetic System 1984 Default datum
  on Garmin and most other GPS receivers. Most
  accurate datum, but not yet in wide use on maps.
• NAD27 (NAD27CONUS) North American 1927 Older
  datum used on most USGS topographic maps. (We
  will be using this datum for the workshop)
• NAD83 North American Datum 1983 Very similar to
  WGS84. Used on newer USGS maps.
• and hundreds of others!

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Commonly Used Map Datums

• WGS84 World Geodetic System 1984 Default datum
  on Garmin and most other GPS receivers. Most
  accurate datum, but not yet in wide use on maps.
• NAD27 (NAD27CONUS) North American 1927 Older
  datum used on most USGS topographic maps. (We
  will be using this datum for the workshop)
• NAD83 North American Datum 1983 Very similar to
  WGS84. Used on newer USGS maps.
• and hundreds of others!

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Coordinate Systems

• LATITUDE / LONGITUDE (ANGULAR) DEGREES -
  MINUTES - SECONDS
• UTM / UPS (RECTANGULAR, METRIC)
  UNIVERSAL TRANSVERSE MERCATOR
  (WE WILL BE USING UTM IN OUR FIELD EXERCISES)
  UNIVERSAL POLAR STEREOGRAPHIC
• MGRS (UTM USING ALPHANUMERIC I.D.) MILITARY
  GRID REFERENCE SYSTEM
• OTHERS
• TOWNSHIP RANGE, STATE PLANE COORDINATE, ETC.

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THE END