Recent Advances in GPS/GIS/Remote Sensing
TechnologiesEGUG Conference
Galveston, TX
October 15, 2003
By: Ashok Wadwani
Applied Field Data Systems, Inc.
Houston, Texas
Phone No.: 281-579-0492
e-mail: [email protected]
ADVANCES IN GPS/GIS/REMOTE SENSING TECHNOLGY
Ease of use-Minimal training
Economical
Hardware-Lighter
AREAS OF ADVANCEMENTS
GPS RECEIVERSDATA COLLECTORSFIELD DATA COLLECTION SOFTWARELASER RANGE FINDERDIGITAL CAMERAS AND GISAVLREMOTE SENSING ARC GIS EXTENSIONS
GPS RECEIVERS
SmallerCheaperGPS AccuracyWith the elimination of SA, autonomous accuracy is much better. Stand alone accuracy of about 10 meters.Availability of Coast Guard Beacons and WAAS for DGPSReal time differential service available throughout the world at reasonable cost
COAST GUARD BEACONS
Available in several areas of the country and plans are to have the entire USA covered.Download coverage areas from the National Atmospheric Administration web site.
DGPS CORRECTION-WAAS
WAAS-WIDE AREA AUGMENTATION SYSTEMFAA is developing this system to help commercial aircraft use GPS as means of navigationNet work of reference stations monitoring and calculating standard GPS errors and broadcasting through geostationary satellite
DGPS CORRECTION-WAAS CON’T
Correction method similar to Coast Guard Beacon except beacon broadcasts corrections from ground stations at low frequency which are more susceptible to weather interference and has limited rangeWAAS provides extensive coverage which is less susceptible to weather, signal interference
DGPS CORRECTION-WAAS CON’T
Provides about 3 meter accuracy 95% of the timeBetter accuracy is experienced in lower latitudes. Accuracy worsens as you head north and is worse along northern most areas from Seattle through Chicago and BostonAs more satellites are launched this will change & entire U.S. is expected to be covered
DATA COLLECTORS
TRADITIONAL UNITS FOR DATA COLLECTION
For data collection, traditional GPS units use either:
On board memory orExternal data loggers
DISADVANTAGES OF TRADITIONAL DATA
COLLECTORS
In most cases, software is difficult to learnUnits are vendor specific to GPS enginesCannot be used for anything else.Proprietary operating systemSlow processor - difficult to manipulate dataSmall screen sizeLow battery lifeReplacement units expensive
NEW GENERATION DATA COLLECTORS
Hand held Personal Digital Assistant (PDA) and ruggedized PC’s.
Palm PilotsUnits with Windows Pocket PC operating systems -PDARuggedized PC’sTablet PC’s
MANUFACTURERS
DAPSHARPHP/COMPAQTRIPOD DATA SYSTEMSVIA
WALKABOUTPANASONICFUJITSUJUNIPER SYSTEMSPSION
Panasonic Toughbook 07
Hammerhead TDS Ranger
TDS ReconPanasonic Toughbook 01
AllegroCompaq iPaq
Compaq iPaq Rugged Case
Enhance the durability of your iPaq Pocket PC without sacrificing style.
The Rugged Case provides:
•Increased durability of the iPaq Pocket PC and drops from up to four feet
•Compliance w/ IP54 standards for water and dust resistance
•Access to ipaq Pocket PC jacks, ports, and Expansion Pack slots
•A clear, hard plastic window that prevents screen damage and allows use of touchscreen and buttons
•Removable belt clip
Pretec Compact Flash GPS Card
Specifications•CompactFlash size card: 36.4mm X 42.8mm X 3.3mm •Product Application: Windows CE, Pocket PC, Automotive applications, Marine Navigation, Aviation, & Timing applications:Time Mark: Once per second•Reacquisition: Hot Start = 8 sec., Warm Start = 38 +/- 5 sec.,Cold Start = 48 +/- 5 sec.•Navigation Update Rate: Once per second• Serial Data Output Protocol: SirF binary serial I/O messages or NMEA-0183 serial I/O messages•Power Consumption: Operation Current = 190mA +/-10%, Power: = 0.63W +/- 10%•Environment Conditions:Operating temperature: 0 degrees C to 50 degrees CHumidity: 95%
ADVANTAGES OF NEW GENERATION DATA COLLECTORS
Economical - $300-6,000 (?) Easy to use - most of the users are already familiar with the Palm, Pocket PC operating systems, and Windows O/S.Can be used with or without GPSCan be used for other applicationsLong battery lifeLight WeightColor DisplayVoice Recording systemsPen-based 2 serial portsMemory cards
FIELD DATA COLLECTION SOFTWARE
TRADITIONAL FIELD DATA COLLECTON SOFTWARE
Difficult to learnVendor specific to their GPS enginesExpensiveOperate only on Windows platform
NEW SOFTWARE
FIELDWORKER
SOLO ARCPAD LANDMARK OTHERS
ADVANTAGES OF NEW SOFTWARE
Economical - $500 - $1,000Have capability to add background maps or digital orthophotosWill run with MR. SIDNot vendor specific to GPS engineRecreational to survey gradeEasy to useCan edit data dictionary in the fieldMost of them have a similar version running on the PC, so learning and training is easier.Accept two serial inputs simultaneouslyDigital camera input
EXAMPLE SCREENS
RASTER IMAGES
IMAGE
FEATURE PROPERTIES
LOGGING DATA
OFFSETS
EXPORTING
EXAMPLES OF DATA DICTIONARY
Poles- Material: wood/metal-Diameter-Asset no.- Manufacturer- Number of conductors-Location
EXAMPLES OF DATA DICTIONARY (CON’T)
Transformer- Location- Rating: -Accessible: Y/N-Inventory Number-Manufacturer
LASER RANGE FINDERS
Data acquisition challenge #1 “You can’t get there from here”
Terrain separates you from the feature you want to map.
Data collection challenge #2“You can get there ... but don’t want to”
Also known among field mapping technicians and postal delivery personnel as the Doberman factor.
Data collection challenge #3“You can get there ... but the satellite can’t”
Data collection challenge # 4“You can get there, and there, and there .....”
To address these challenges, consider using laser mapping systems
The key to laser mapping is ...
You don’t have to get there from here!Instead, just shoot it with the laser.
What makes a laser mapping system work?
Eye-safe diode pulse laser measures distance without reflectors.Digital flux-gate compass or angle encoder (not affected by magnetic fields)Electronic tilt sensor determines vertical angle.
General range finding specifications
Multiple pulse averaging gives better accuracy.Mapping grade lasers vary in accuracy from about 5 cm. up to 1.5 meters.Maximum range varies from 1000 ft... up to 2500 ft.
Direct GPS Integration
Data loggingdevice
GPS
CRITERION
Laser gun
Indirect laser / GPS integration
GPS
Laser
Features
Independent laser mapping
Laser with data collection hardware and software.Base map coordinates or survey markers provide reference points.Features are accurate to base map and to each other.Can be geo-referenced again when more accurate base maps become available.Requires origin coordinates.
TYPICAL APPLICATIONS FOR LASER RANGE FINDERS IN UTILITIES
Light pole inventory to determine horizontal distance, height and slopesMeasurement of line pulls, line sag, bridge spansLine clearancesLay out surveys for transmission tower planningTree conductor clearanceMapping of large number of features eg poles and which are hard to reach
DIGITAL CAMERA AND GIS
MediaMapper
A desktop mapping software that links pictures and other files to GIS map layers.Creates “media maps” that can be used in Arcview GIS, MapInfo Professional, or on the web.The mapping solution for GIS users wanting a fast, easy way to link photographs or other multimedia files to map locations.
How MediaMapper Works With Digital Still Pictures
Take digital pictures while recording GPS data.Media Mapperdownloads the pictures and the GPS data file.Click the map to view the pictures of location.
Get the Picture … Make the Map
Take Pictures and Collect GPS data
Pictures Link to Map Via GPS
Metadata
Download to MediaMapper
Customize the Map
Environmental Application
Pollution MonitoringEnvironmental Assessment ProgramsHazardous SpillsPublic Education and OutreachMandatory ReportingWaste Contamination PointsCleanup AreasEnvironmental Data CollectionWater ManagementWetlands
Benefits
Works with Off-the-Shelf ComponentsSmall, Lightweight for Individual UsersNo Need for Expensive Outside ProgramsSimple to OperateFast Turnaround from the Field to the InternetQuick Association of Images with MapsCreates .shp, .tab, or html maps
AVL
Economical AVL units available for monitoring location of field crews in real time.Dispatch center can locate every individual truck in real time.End of day reports with information on miles traveled, stop time, drive time, places visited etc. Data transfer via radio, satellite, cell phones etc.2-way communications
REMOTE SENSING
Due to launching of new satellites, and improved digital aerial sensors quality and quantity of aerial data has improved several folds
ArcGIS SOFTWARE EXTENSIONS
IMAGE ANALYSISSTEREO ANALYST
IMAGE ANALYSIS
Operates on ESRI ARCGIS 8.3Facilitates extraction of ImageryCreation of GIS ready imageryLand cover classificationChange detectionImage re projectionMosaicking
STEREO ANALYST
Operates on ESRI ARCGIS 8.3Performs 3D stereo feature collection in Geodatabase2D TO 3D feature conversion tools for updating feature data set.Supports CAD formats
Change Detection
Example – Damage Assessment
Image Analysis
Example – Damage Assessment
Image Analysis
Example – Damage Assessment
Image Analysis
Future developments -Feature Updating – Roads