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Intro to Precision AgricultureIntro to Precision Agriculture
Students will be able to define/describe:Students will be able to define/describe:Precision Agriculture, GIS, GPS, DGPS, VRT, Remote Sensing, Precision Agriculture, GIS, GPS, DGPS, VRT, Remote Sensing, Pixel, Spatial Resolution, MultiPixel, Spatial Resolution, Multi--spectral, Data, Information, spectral, Data, Information, Knowledge, WisdomKnowledge, Wisdom
Students will be able to draw diagrams to describe the followingStudents will be able to draw diagrams to describe the followingtechnologies:technologies:
Yield MonitorYield MonitorVariable Rate PlantingVariable Rate PlantingVariable Rate Chemical ApplicationVariable Rate Chemical ApplicationRealReal--Time Differential GPSTime Differential GPS
Precision AgriculturePrecision Agriculture
AKA:AKA:Precision FarmingPrecision FarmingFarming by the InchFarming by the InchSiteSite--specific farming/agriculture/applicationspecific farming/agriculture/applicationPrescription FarmingPrescription FarmingSpatiallySpatially--Variable Crop ProductionVariable Crop Production
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SiteSite--Specific ProcessSpecific Process
VRT: Fertilizing
Site-Specific Scouting and Sampling
Yield Monitoring
Spraying
Seeding
TechnologiesTechnologies
Global Position System Global Position System –– GPS GPS –– Latitude and LongitudeLatitude and LongitudeYield MonitorYield MonitorGeographical Information Systems Geographical Information Systems –– GISGISDecision Support Systems Decision Support Systems –– DSSDSSSiteSite--Specific Sampling of Soil PropertiesSpecific Sampling of Soil PropertiesVariableVariable--Rate Application of Fertilizers and PesticidesRate Application of Fertilizers and Pesticides
The enabling technology for precision agricultureis position sensing, namely GPS.
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Global Position System: Global Position System: OverviewOverview
US DoD - GPS
US DoD - GPS US DoD - GPS
US DoD - GPS
US DoD - GPS US DoD - GPS
Latitude and Longitude CoordinatesLatitude and Longitude Coordinates
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Ag Mall, Lafayette, IndianaAg Mall, Lafayette, IndianaDecimal DegreesDecimal Degrees
Latitude: Latitude: 40.42233854Longitude: Longitude: -86.91510721
Degrees, Minutes, Seconds: DMSLatitude: 40° 25’ 20.4”Longitude: -86° 54’ 54.4”
Note the minus (-) sign indicates Longitudes which are West of the Prime Meridian.
GPS InformationGPS InformationABE local:http://danpatch.ecn.purdue.edu/~asm322/GPS/GPS.html
Trimble Tutorial: http://www.trimble.com/gps/US Army Tutorial: http://tsc.wes.army.mil/gps/gps.htmSmithsonian NASM Tutorial:http://www.nasm.si.edu/exhibitions/gps/index.htm
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GPS Precision GPS Precision -- UncertaintyUncertainty
GPS ReceiverGPS ReceiverNumber of satellites which can be receivedNumber of satellites which can be receivedAccuracy of clocksAccuracy of clocks
Satellite GeometrySatellite GeometryAtmospheric ConditionsAtmospheric ConditionsDifferential Correction SourceDifferential Correction Source
None None -- ~50 feet~50 feetWAAS (Wide Area Augmented Service) WAAS (Wide Area Augmented Service) –– ~10 feet~10 feetCoast Guard Beacon Coast Guard Beacon -- ~3 feet (distance to station ~3 feet (distance to station and weather)and weather)Satellite Subscription Satellite Subscription -- ~ 3 feet~ 3 feet
GPS Precision GPS Precision -- Uncertainty ReportingUncertainty Reporting
CEPCEP –– Circular Error Probability Circular Error Probability –– 50% are inside circle 50% are inside circle of this radius for stated time period of this radius for stated time period Trimble Ag 132 DGPS receiver Trimble Ag 132 DGPS receiver –– CEP of 1 meter for CEP of 1 meter for
24 hours24 hours
Pass to PassPass to Pass –– measured over a short time periodmeasured over a short time periodTrimble Ag 132 DGPS receiver Trimble Ag 132 DGPS receiver –– Pass to Pass Pass to Pass
uncertainty of less than 12 inches.uncertainty of less than 12 inches.
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GPS HardwareGPS Hardware
GPS ApplicationsGPS Applications
Position Logging:Position Logging:Boundaries Boundaries –– fields, crop areas, areas of interestfields, crop areas, areas of interestPoints Points –– locations of obstacles, sites of interestlocations of obstacles, sites of interestPaths Paths –– location of fence, watercourse, etc.location of fence, watercourse, etc.
GuidanceGuidanceNavigate to point for siteNavigate to point for site--specific samplingspecific samplingSwathSwath--width guidance, e.g. lightwidth guidance, e.g. light--barsbars
Controlled Steering Controlled Steering –– automatic, selfautomatic, self--guided vehiclesguided vehicles
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Position LoggingPosition Logging
FarmworksSiteMate
BlueTooth Airlink
Guidance to a Guidance to a Predetermined Predetermined
PointPoint
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Guidance: SwathGuidance: Swath--WidthWidth
AgleaderAgleader PF3000 + GPS + PF3000 + GPS + LightbarLightbar
LightbarLightbar (Trimble)(Trimble)
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Guidance: Guidance: Swath WidthSwath Width
120SETALeft Display Right Display
Cross Track Distance LED's
Steering Angle LED's
Turning Direction
Bearing
1Spray On
R 2.5Crosstrack Distance Swath Number
Guidance: Guidance: SwathSwath--WidthWidth
Pass to Pass Accuracy:~6 to 18”(10 minutes)
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Controlled Controlled Steering: Steering: AutoTracAutoTrac
Advertised Accuracies:~10 inches~1 inch with RTK
Base Station within ~10 miles
Hydraulic Control Valve on Power Steering
Controlled Steering: AutoControlled Steering: Auto--GuideGuide
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Global Global Position Position SystemSystem
Communications Satellite
Questions ????Questions ????