Using GPS and GIS for Landscape Management Mike Binkley The Davey Tree Expert Company

Global Positioning System Global Navigation Satellite System (GNSS)Global Navigation Satellite System (GNSS) –NAVSTAR GPS - US Military –GLOSNASS – Russia; 2011 –Galileo – European Union; 2010

Global Positioning System NAVSTAR Global Positioning SystemNAVSTAR Global Positioning System –1978 –Multiple satellites –USAF 50 th Space Wing –$400 million/yr –Between low and high earth orbit Three Segments:Three Segments: 1.Space 2.Control 3.User

Global Positioning System Space SegmentSpace Segment –24 satellites in 6 orbits –12,000 miles up Control SegmentControl Segment –USAF tracking stations –Clock synchronization User SegmentUser Segment –GPS Receiver

625 Mi 690 Mi 625 Mi Global Positioning System How it WorksHow it Works –GPS Receiver measures time between transmission and reception of satellite signals 615 Mi 625 Mi 690 Mi –Time = Distance to satellites (b/c of fixed signal speed) –3 satellites for “trilateration”

Global Positioning System GPS ReceiversGPS Receivers –Antenna, signal processor, clock –Multiple-channels FunctionFunction 1.Listen for satellite signals 2.Compare time delay 3.Compute distances to satellites 4.Trilaterates position

Global Positioning System Sources of ErrorSources of Error –Atmosphere –Local EM sources –Nearby Reflection (“Multipath”) –Signal Blockage –Bad time of day

Global Positioning System AccuracyAccuracy – more $$$ = greater precision – sources of error –High-end equipment – sub-foot to 10 feet; roving –Consumer equipment – 1 to 25 feet; roving –Vehicle equipment – 1 to 25 feet; snapped to road Improving AccuracyImproving Accuracy –Base stations –“Post-Processing” How much accuracy do you need?

Global Positioning System EquipmentEquipment –Survey Grade ($$$$$) –Mapping Grade ($$$$) –Consumer ($) –Vehicle navigation –Vehicle tracking

Global Positioning System USESUSES –Where am I? –Where are my assets on the property? –Where is the (broken) valve (under the snow), –Where are my customers / crews / vehicles? –Where is my expensive spray tank / boom truck? –What are the best routing scenarios for my crews? –How many miles did I log last year? –How many were Federal Highway miles?

Geographic Information Systems Combination of:Combination of: –Hardware –Software –Training Map Data Fast Chip, lots of RAM, lots of Storage Used for:Used for: –Visualizing –Creating –Managing ESRI, MapInfo, Manifold WKSPs, classes, degrees, books “Geographic Database”“Geographic Database”

Geographic Information Systems Map DataMap Data –Organized into layers –Different types… Facilities Vegetation Soils

Geographic Information Systems Map DataMap Data –Features on separate map layers organized as: Points - trees - transmission towers Lines - roads - transmission wires Polygons - lakes -vegetation areas *Images -air photos

Geographic Information Systems Map DataMap Data –Each point, line,or polygon tied to one database record –Feature info stored in each record across separate fields. –Other tables linked to main table (work records) (work records)

Geographic Information Systems Map Data ChallengesMap Data Challenges –Variety of sources –Variable Costs –Projection, datum, units –Integration with CAD

Geographic Information Systems TheoryTheory

Geographic Information Systems ImplementationImplementation

Geographic Information Systems Mobile ImplementationMobile Implementation

Geographic Information Systems UsesUses Turf Analysis – enviro factors

Geographic Information Systems Turf Analysis – area calculations

Geographic Information Systems Asset Inventory and Management

Geographic Information Systems Map Production

Geographic Information Systems 3D Modeling

Geographic Information Systems CustomizationCustomization