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Participatory use of GIS using mobile GIS. Jeroen Verplanke. Using GPS and PDA in Practice. About PDA the Personal Digital Assistant. The HP-iPAQ pocket PC 64 Mb RAM memory - no HDD 16Mb – 256Mb optional SD memory 400 Mhz processor running MS-Windows-CE 4 – 8 hours operating time
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Participatory use of GISusing mobile GIS Jeroen Verplanke
About PDAthe Personal Digital Assistant • The HP-iPAQ pocket PC • 64 Mb RAM memory - no HDD • 16Mb – 256Mb optional SD memory • 400 Mhz processor • running MS-Windows-CE • 4 – 8 hours operating time • Highly portable but small screen
Tablet PC • Full PC (Windows XP & all software) • Pentium M 1 GHz processor • 512 Mb RAM • 30 GB hard disk • Large screen • (only) 4 hours operating time
Compaq 3950 256Mb flash About Pocket PC (PDA) • Easy installation of software • Easy synchronization of files
About ArcPad™ • Convert GPS readings ‘on-the-fly’ to the coordinate system in use. • Any image, GT-Sheet, or shapefile can be displayed in Arc-Pad. • The user can save the GPS-Track log (as points), or prepare new shape files. • The software also allows to prepare forms
SID IMG About ArcPad™ By using MrSID data compression Images can be compressed by a factor 25!!! Example: compressed from 25 to 1 MB.
Field Connecting Hardware GPS physical connection A GPS serial connector wire needs to be linked to a serial connector wire attached to the iPaq. Both ends are female and need to be connected through a null-modem connector in which pins 2 and 3 are reversed (home made…).
Field Connecting Hardware-2 GPS physical connection A GPS serial connector wire needs to be linked to a serial connector wire attached to the iPaq. Both ends are female and need to be connected through a null-modem connector in which pins 2 and 3 are reversed (home made…).
Field Connecting Hardware-3 Connection precaution Use tape to provide the required solid ‘fix’. Connectors are not built to support much weight.
Fully integrated solution Hardware alternatives • “Jacket” GPS • Bluetooth GPS • Comparable accuracy • Less options (black box) • All in one ruggedized GPS
Hardware settings: ArcPad • Arc-Pad settings • GPS: NMEA protocal, WGS84 Datum • GPS Port: port com1, Baud 4800, Parity none, Data bits 8, Stop bits 1, Break 0.
Hardware settings: GPS • GPS settings • units’ settings: position format: hddd.dddddo, map datum: WGS 84, and units: metric • ‘interface’ settings: i/o format: NMEA out, and baud rate: 4800.
Accuracy Performance under trees Cycling to work during a cloudy morning provided the yellow line. It is projected on AP’s, an Ikonos image and the Top-10 of Enschede. Where high trees were present, tracking with the GPS give visible errors. ArcPad can provide accuracy warnings !!!
GPS-iPaq Warnings • Not for GIS amateurs • Requires user to know facts on projection systems ‘properly’ • Requires proper preparation: • of geo-referencing images • of compressing images • of converting shapefiles • of preparing symbologies • of preparing forms • Requires proper GPS-ArcPad software settings