K-12 Education: Integrating GIS and GPS

April 1, 2008

Global Positioning Systems

• GPS is a revolutionary navigation systemo 24 satellites orbiting the

eartho Provide location within

metres or less anywhere on the globe.

o Now available in many cars as an option

o Created and operated by the US Department of Defense

More about GPS satellites

• Constellation of 27 satelliteso (24 active + 3 spare)

• Orbit 12,600 miles above eartho (10,900 nautical miles)

• Satellites in 12 hour orbit• First satellite launched in 1978, 24th became

operational in 1994• Selective availability was removed in May,

2000o Handheld receivers are now much more accurate

How does GPS work?

• Measuring distance by measuring time• Satellites send coded signals indicating their

position in space and the exact time the signals are being sent

• Receivers use the time it takes signal to travel from satellite to receiver to determine distance from satellite to receiver

• Information from multiple satellites is used to determine position through ‘triangulation’

How does GPS work?

More about GPS receivers

• A GPS receiver's job is to locate four or more satellites, figure out the distance to each, and use this information to deduce its own location. o Hand-held receivers for recreational

use with accuracy of 10-15 metreso Vehicle mounted receivers for

navigation or agricultural use with accuracy of < 1 metre

o Backpack or tripod mounted receivers for surveying use with accuracy of 5 – 10 centimetres

More about GPS receivers

• Receivers require clear line-of-sight; thus, they will not work indoors or where tall objects obscure the sky

What’s so cool about GPS?

• GPS unitso Can be used as a digital compasso Can be used to determine ground speedo Can store landmarks (locations)o Can be used for dynamic routingo Can be used for mapping applications

Applications of GPS

• In-vehicle Navigation (car, boat, airplane)• Asset Management• Construction• Geologic Research & Mining• Military Navigation and Operations• Mapping & Surveying• Precision Agriculture• Public Health • Public Safety• Wireless Communications

GPS in the classroom

Integrating GIS and GPS

• Collect a series of latitude and longitude points using GPS receiverso add them into an existing digital map

• Skills in o data collection/creationo GPS readingo observation

• Digital photos

Geocaching

• A great way to introduce students to GPSo Teach latitude/longitudeo Take advantage of the wonderful features and

capability of your GPS unit• An entertaining adventure for GPS users

o Individuals and organizations all over the world have set up caches and shared the locations of these caches on the Internet

o Participate in a cache hunt to find an existing cache or create your own

• www.geocaching.com

Classroom projects

• There are many ways you can incorporate GPS data collection into your classroom

• Possibilities includeo a virtual trail in your areao mapping the locations of litter and garbage cans to

determine if there is a relationship, and if more garbage cans are necessary

o collecting data about tree types and locations on school grounds and beyond

o gathering water samples from a local stream and taking GPS readings at each location

o orienteering/navigating (hiking, boating, biking, driving)

Getting started

• GPS units - Garmin eTrexo perfect for introducing students to field

data collection and the power of GPSo industry's smallest and lightest

handheld GPS receivero sleek waterproof housing will fit in your

shirt pocket and weighs only 5.3 ounces

o a 12 channel parallel receiver, differential ready, with a built-in patch antenna

o runs for 22 hours on just two AA batteries

• Pencil, clipboard, paper

Getting started - additions

• Connection cables for your GPS unitso Allow you to download data from your GPS unit to

your computero Free extension available to convert to shapefile

• Local datao Create a base map for viewing the data you have

collectedo Provides context and other features for GIS

analysis with ArcView• Digital camera

Collecting data

• Collect data in the field using GPSo Write down point coordinates and additional

data observations - OR - o Use tracking function of your unit to store

points, lines, or polygons, and write down additional observations

Using the data you collect

• Manually enter the coordinates and observations into a table (Excel, etc.)o Save as a .dbf fileo Add to ArcViewo Use “Add X,Y” or “Add Event Theme” to

create points on your map - OR -

• Use your GPS unit cable to download the data from the unit to your computer

For more information…

• Books from ESRI Presso Integrating GIS and the Global Positioning

System Karen Steede-Terry

o Fun with GPS Donald Cooke

o Community Geography: GIS in Action Kim Zanelli English and Laura S. Feaster

For more information…

• Lessons on the ESRI Canada websiteo http://k12.esricanada.como Integrating GIS and GPS (ArcView 3.x)o Exploring Pukaskwa National Park (ArcView

8.x/9.x)• Garmin website

o http://www.garmin.com/• Trimble GPS

o www.trimble.com/gps• How stuff works

o www.howstuffworks.com