Project IIa GPS Jeff Houston Jeff Filson Tim Culbreth Jennifer Martin

Project Deux: In this project you will: Learn how GPS works Learn how to use a handheld GPS unit Locate places using GPS Enter locations into the GPS device Import GPS data into ArcView Create a map with GPS data Experience fun

How GPS Works 24 US GPS Satellites Broadcast precise time signals GPS receiver compares received time signals with actual time to determine distance from satellite 3 satellites need to triangulate a 2D position, 4 or more to get a 3D position (altitude). Garmin, 2006

Other Information the GPS Unit can calculate: Speed Direction Sunrise, sunset times Track a path Distance traveled Distance and direction to set waypoints

Waypoints Waypoints are set by the user manually, entering long. and lat. or importing from a database or entering by marking a location in the field. Can be use to set paths or find locations. This GPS unit can hold up to 500 waypoints with specific names and/or symbols.

404: LOCATION NOT FOUND Sources of error Atmospheric disturbances Reflection off of objects (trees, buildings, etc…) Clock errors Errors in a satellite’s orbit Too few satellites Satellites at bad angles (ex: too close together)

More information For more information on how GPS works, check out these sites:

Using The Hand Unit GPS in the Field

Getting Started Press the “ON” button, it has an image of a red light bulb. Let it get a satellite signal (need to be outside) Press “Quit” once to bring up the main menu Press “Enter” on the waypoint menu option

Changing Lat/Long Display If your coordinates are in a non-decimal format go to the “Main Menu” screen by pressing the “Page” button. Go into the “Setup Menu”, go into “Navigation” Highlight “Position Frmt” press “Enter” to select it and scroll through the options until you land on “hddd.ddddd” select this so all your coordinates will be set to decimal format.

Entering Mystery Waypoint Press “Up” Press “Enter” Scroll through letters with the arrow pad to make the name “Point 1” Press “Down” twice to highlight coordinates, Press “Enter” and use arrow keys to scroll through numbers and enter your desired coordinates. Once your coordinates are entered press “Done”

Finding Mystery Waypoint Press “Quit” button twice to arrive at the map. Highlight the upper left corner with the map size on it using the side arrow. Press “Enter” to increase size of map use “Up Arrow.” Highlight point “P” and start walking toward your waypoint.

Making Your Waypoints Pick 4 locations on campus, go to those locations Press “Mark” button Highlight the “Waypoint” (actually a number until you name it). Press “Enter” and enter a name for your waypoint by scrolling through the letters. Press “Enter” and Save (bottom of screen)

GEOG 121 Project 2b: Integrating GPS and GIS

Review of GIS Part B of this project requires you to put together both data from the GPS and the GIS to make a usable map product Recall that GIS, or Geographic Information Systems, is a decision making tool used to make geographical data into geographic information

Step 1: Downloading GPS Points with Waypoint To start, plug your GPS unit into the back of your computer Open Waypoint under All Programs and Geog 121 Go to GPS tab and download from GPS and then to Waypoint

Step 2: Formatting Points Next you need to specify the coordinate system and datum This is important because without a coordinate system and datum specified, the GIS software can’t re-project the points correctly from the GPS –To specify the coordinate system go to Configure, and click on Decimal Degrees and Meters –To specify the datum go to File, Datum and click on WGS84 Then save the file by going to File, Save

Step 3: Using Excel Open Excel, click file open and select the Waypoint text file Select delimited and click next Set delimiters as only comma and click finish Reformat the newly opened file into 3 columns: Waypoint, Latitude, and Longitude as shown below Save as a text file

Step 4: ArcView 9.1 Download map of campus from Angel –Note that it’s a zip file, and will need to be extracted Open ArcMap, go to File, add data. Look under Campus Shapefiles and open campus_spc_nad83.lyr Next you have to manually re-link all the layers –Right click psu_bldg, go to properties, click source tab, set data source button. Find psu_bldg.shp and add –Repeat for next two layers

Step 5: Re-project Map The Campus Map was created using State Plane Coordinate System But this needs be re-projected to WGS 1984 so that it matches the GPS data Right click on layers, go to properties, click on coordinate system tab Go to Predefined, Geographic coordinate systems, world, WGS 1984.

Step 6: Importing GPS data Go to tools, add XY data. Click on browse button and find the saved waypoint text file Set X field as longitude and Y field as latitude Click edit to set coordinate system, select, geographic coordinate systems, world, WGS84

Step 7: Saving Map Image Go to file, export map, save file as a jpeg, set resolution to 72. Click Save. The END…..

Citations DiBlase, David; Understanding Geographic Data, ESRI Virtual Campus Module 1: What Are Geographic Data?, Accessed Oct 12http://training.esri.com/