Presentation on theme: "GPS Handhelds Erin Miller Suzette Stone. Introduction At one time all GPS units attempted to cater to everyone. Currently more specialized units are available."— Presentation transcript:
GPS Handhelds Erin Miller Suzette Stone
Introduction At one time all GPS units attempted to cater to everyone. Currently more specialized units are available. You need to understand exactly what you intend to do with a GPS unit before you buy one. It is a good idea to explore a few features beyond the basics. Today we are focusing on lower-end GPS handhelds with an accuracy generally less than 15 m. These can be used for outdoor recreation, navigation, the marking of landmarks or other points, but not for survey grade applications.
Things to Consider The many uses of GPS Computer interface to be able to download data. Uploading maps of areas you intend to visit. A unit with an interface that you are comfortable with. What is most important to you? Are the datums you require available? Which paper maps, if any, will you be using along with your unit? What type of interface? Do you need additional software and cables? Do you want internal maps? What uploading capabilities and amount of space is available? Battery life? Waterproof? Available accessories how accurate do your downloadable maps need to be? Need DGPS? WAAS?
Keep in Mind A navigation receiver is not a survey device but it more accurate than most of the digitized maps you use it with. Remember many of these maps were digitized using paper maps.
The Comparisons Garmin Etrex Series Other Garmin units Thales Navigation units (formerly Magellan)
ManufacturerGarmin Model LegendVentureVista Size (WxHxD)4.4”x2.0”x1.2” Weight5.3 oz Batteries/life2AA / 18 hrs2AA / 20 hrs2AA / 12 hrs Waypoints500 Routes20 / 50 ea Display Size2.1” x 1.1” Upload memory8MB1MB24 MB O.Ext.antennaeN/A Basemap Worldwide city Db Basemap Map optionsMapSource CDPts of Interest CDMapSource CD WAAS enabledYes Compass/AltimeterNo / No Yes / Yes Accuracy<15 m <3mWAAS List Price$268$194$375
ManufacturerGarmin ModelEmapGPS 12 MapGPSMap 76 Size (WxHxD)5.5”x2.4”x0.8”5.8”x2.1”x1.2”6.2”x2.7x1.2” Weight6.7 oz9 oz<16 oz Batteries/life2AA / 12 hrs4AA / 36 hrs2AA / 16 hrs Waypoints500 Routes50 / 50 ea20 / 30 ea50 Display Size2.2” x 1.7”2.2” x 1.5”1.6" x 2.2" Upload memoryOnly w/ card1.44 MB8 MB O.Ext.antennaeYes BasemapBasemap ** Detailed b.m*** Map optionsMetroSourceMapSource CDs WAAS enabledNo Yes Compass/AltimeterNo / No Accuracy<15 m <3m WAAS List Price$242$364$400
The Potential of WAAS Wide Area Augmentation System 100 meters:Accuracy of the original GPS system under Selective Availability (SA) program. 15 meters:Typical GPS position accuracy without SA. 3-5 meters:Typical differential GPS (DGPS) position accuracy. < 3 meters:Typical WAAS position accuracy.
ManufacturerGarmin Thales Navigation Model Vista GPSMap 76Meridian GPS Size (WxHxD)4.4”x2.0”x1.2”6.2”x2.7x1.2”6.5”x2.9”x1.3” Weight5.3 oz<16 oz8 oz Batteries/life2AA / 12 hrs2AA / 16 hrs2AA / 14 hours Waypoints500 Routes20 / 50 ea5020 Display Size2.1” x 1.1”1.6" x 2.2"1.75”x2.2” Upload memory24 MB8 MBOpt card 8MB $34 O.Ext.antennaeN/AYes Basemap Detailed b.m***US Cities, airport Map optionsMapSource CDMapSource CDsMapSend CD WAAS enabledYes Compass/AltimeterYes / YesNo / No Accuracy<15 m <3mWAAS <15 m <3m WAAS <15m <3m WAAS List Price$375$400$210 ($244)
Costs for Map Add-ons Garmin Metroguide$ Garmin Waterways$65.00 Garmin Road & Recreation $ MapSend for Meridian – Streets & Destinations $80.00
In closing For the types of uses we were searching for Basic functions for primarily recreational use Ability to contain some basic street information as well as uploading features The accuracy that is possible with WAAS technology The Meridian GPS by Thales Navigation seems to be the best choice.
References Garmin Thales Navigation Yahoo Shopping (for prices not listed on corporate sites) Trimble “Receiver Survey” GPS World January 2001