Evolution of Global Positioning System Guidance Technology Dustin Holden 4-21-2006

Topics of Discussion What is GPS and how does it work? Where did GPS come from? When did Ag GPS become available? How is Ag GPS used today? How will Ag GPS be used in the future?

What is GPS and how does it work? GPS in general How does it work

What is GPS and how does it work? GPS in General 24 Rockwell International Navstar Satellites Altitude: 12,550 miles Weight: 1900 lbs (in orbit) Orbital Period: 12 hours Planned Lifespan: 7.5 years 5 Ground Based Monitoring Stations United States: Hawaii, Colorado South Atlantic: Ascension Island Indian Ocean: Diego Garcia Marshall Islands: Kwajalein

What is GPS and how does it work? How it works Triangulation Measure distance using travel time of radio signals Timing Location of the satellites Delay error correction

Where did GPS come from? Child of Cold War Department of Defense Navstar system developed in early 1970’s First six Navstar satellites launched 1978 - 1980 Balance of 24 NAVSTAR satellites were launched in 1980’s First civilian products appeared in mid 1980’s In 1995 the system reached full operational capability

When did Ag GPS become available? 1992 First agricultural aerial guidance system 1993 First compact light bar 1995 First USCG Beacon DGPS receiver targeting agriculture 1997 First GPS receiver for agriculture with choice of correction 1999 First Real-Time Kinematic (RTK) receiver for agriculture 2003 First non-laser automated leveling system for agriculture

How is Ag GPS used today? Precision Tillage / Planting Spraying Harvesting Leveling

How is Ag GPS used today? Precision Tillage / Planting Light Bar Guidance Auto Steer Terrain Correction

How is Ag GPS used today? Spraying Green Seeker Swath Control Pro

How is Ag GPS used today? Harvesting Yield Monitoring

How is Ag GPS used today? Leveling Differential GPS Real Time Kinematics GPS

How will Ag GPS be used in the future? Fully automated farming?

References http://www.trimble.com/index.aspx http://stellarsupport.deere.com/en_US/ http://www.emory.edu/BUSINESS/et/552fall2002/locationdevices/gps_-_history.htm http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html http://www.cmtinc.com/gpsbook/index.htm