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GPS devices can be found everywhere Basic GPS for Field Course Mingzhi Qu Ph.D. candidate, Dept. of Biology { Queen’s University July 2015

When we talk about GPS “GPS” is not the only position system in the world… - What is the Global Positioning System?

Global Positioning System Ñ Brief history of GPS (GPS) Ô Started development in 1973 Ô First four satellites launched in 1978 Ô Full Operational Capacity (FOC) reached on July 17, 1995 Galileo Positioning System Ô System cost of $12 billion(eq to 55 B) (Galileo) Ô GPS provides both civilian and military positioning globally Ô GPS comprised of three “segments” Global Navigation Satellite System Ò Space Segment (24 satellites plus (GLONASS) spares) Ò Ground Segment (the ground control network) BeiDou Navigation System Ò User Segment (GPS receivers and (COMPASS) their users)

How Does GPS work? How Accurate is it? Ñ Depends on the type of receiver, and terrain. If the distance to: Ñ Average handheld receiver: Ó 3 satellites is know n—a 2- Ó 10 to 15 meters – old handheld devices dimensional position can be Ó With Wide Area Augmentation System(WAAS), determined (Longitude & latitude). newer models accuracy up to 3 meters Ó 4 satellites is know n—a 3- Ó Accuracy to about 10cm with Differential GPS dimensional position can be determined (Longitude, latitude, altitude) (Note: this is what you always want to have.)

More satellites—more accurate position. Graphic of person Common handheld Differential GPS devices standing in a 10 m circle devices

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Establish Understand Positioning Positioning A geographic coordinate system is a coordinate system Ñ When we discuss our ‘position’, we always use some form that enables every location on the earth to be specified by of reference frame. a set of numbers or letters. (e.g. Lat/long)

I’m about 10 Meters in front of He lives next to you I’m at North 31 the City Park degree 32 minute 53 seconds and East 120 minute 22 minute

I’m at the center of universe

We need a “common language” to communicate.

The good and bad of the geographic coordinate system Projected Coordinate System

Good: Covers every spot on the earth

Bad: Not a linear unit. You cannot measure the distance through this system.

Defined on a flat, two-dimensional surface, has constant Fair race? lengths, angles, and areas across the two dimensions Walk from 80°N 55 °E à 80 °N 60 °E vs Walk from 0°N 55 °E à 0°N 60 °E

Projected Coordinate System Is this a Projection? Transform three-dimensional surface to create a flat map sheet. This mathematical transformation is commonly referred to as a map projection.

• visualize shining a light through the earth onto a surface, called the projection surface. • Imagine the earth's surface is clear with the graticule drawn on it. • Wrap a piece of paper around the earth. • A light at the center of the earth will cast the shadows of the graticule onto Flatten an orange peel — it will tear. the piece of paper. • You can now unwrap the paper and Representing the earth's surface in two dimensions causes distortion in lay it flat. the shape, area, distance, or direction of the data.

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There are infinite number of Projected coordinate system vs projected coordinate system Geographic (lat/long) coordinate system.

66° 63°60° 84°N 10,000,000m 75°N

60°N 8,000,000m

45°N 6,000,000m

30°N 4,000,000m

15°N 2,000,000m

0°N (Equator) 0m 10,000,000m

Different projections cause different 15°S 8,000,000m

types of distortions. Some projections 30°S 6,000,000m are designed to minimize the distortion of one or two of the data's 45°S 4,000,000m characteristics. 60°S 2,000,000m e.g. A projection could maintain the 75°S area of a feature but alter its shape. 80°S 0m 0m 500,000m 1,000,000m

UTM coordinate UTM coordinate One of the most used coordinate systems

One of the most used coordinate systems

The UTM system divides the Earth between 80°S and 84°N latitude into 60 zones, each 6° of longitude in width.

• Horizontal lines measure Northing • Vertical lines measure Easting. • UTM positions are read Easting first, Easting then Northing. UTM Value Zone No. 18T 395000 4936000

UTM Latitude Band Letter Northing Value

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Question:

18T 395000 4936000 Diving board:

18T 394800 4935400

Boat house:

18T 394920 4935500 meters

What’s the direct distance between Main lounge and Diving board? 493600

0 395000 meters

All those things to set ?

Ó Why do we care about all these numbers? Ô Because all GPS units are configured to work Northing with multiple reference frames, anywhere in differences (100) the world. They give far more information than is required for local navigation. What’s the direct distance between Easting differences(120) Ô Practically, this means YOU must be able to Main lounge and Diving board? configure a GPS to work correctly in YOUR Diving board: zone (with your maps) and be able to extract the important numbers from a position Pythagorean equation 18T 394800 4935400 screen. (UTMs are not single projection) Boat house:

18T 394920 4935500 C=156m

Take home message

Ñ Global Positioning System is a system name, and is not the only position system in the world Basic operation of Ñ 3 satellites gives you a 2-dimensional position, while 4 satellites gives you a a 3-dimensional position. Ñ Unproje cte d coordinate system: handheld GPS unit Ó e.g. Geographic coordinate system Ó based on spherical coordinates, degrees of latitude and lonitude. Mingzhi Qu Not linear unit. Ph.D. candidate, Dept. of Biology Ñ Projected coordinate system: { Queen’s University July 2015 Ó e.g. UTM coordinate Ó Coverts spherical coordinates to flat, planar coordinates, Uses linear units Ñ Projection is the process transform three-dimensional surface to create a flat map sheet. Ñ UTM positions are read UTM Zone No. and Band Letter first, then start with Easting, and Northing.

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What can a GPS unit do for field biologist? What the GPS unit will NOT do? Ñ Provide your current position—anywhere, anytime.

Ñ Ñ Display a line of past positions (a track) and store them. Will not: Ó Give much useful data without a map. Ó Ñ Store a large number of known locations—waypoints. Replace map and compass. Ó Necessarily give an accurate indication of magnetic north or current heading. Ñ Give you real-time estimates on your travel progress. Ó Assist you in getting “home” unless you can tell it where home is. Ó Be accurate over short distances—less than 15m. Ó Be of any use without batteries or a clear view of sky.

Why handheld GPS NOT smartphone Install/Change batteries

Ñ Software and maps Ó Maps for navigation vs Topographic map 1. Remove the battery cover Ñ Accuracy by turning the D-ring 1/4 Ó Better antenna for GPS handheld devices turn counter- clockwise Ñ Durability and battery life and pulling up. 2. Insert the batteries, Ó Water proof observing polarity. Ó AA ba ttery 3. Replace the battery cover. Ó heavy duty button

Turning the Device On or Off Record GPS coordinate

Press and hold on the right of the device to turn device on/off • Number and ID of satellites Quickly press to turn on/off the backlight received. • Indication of signal quality. • Estimated position accuracy. Acquiring Satellite Signals This is a key item for accurate navigating. • It may take 30 to 60 seconds to acquire signals. • Go outdoors to an open area. • Press PAGE (on top of the • Wait while the device searches for satellites. • press PAGE -> power button) • A question mark flashes while the device determines • choose MAIN MENU -> • Until you see this screen appears your location. • use ARROW key -> • find SATELLITE -> • press ENTER

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Setup Position Format, Map Datum Setting Waypoints(航点) Waypoints are locations you record and store in the device.

1.(GPSmap 62s): From any page, press MARK.

(eTrex): go to Menu-> MARK Main Menu Setup Units(eTrex) position format/Heading(gpsmap 62s) 2.Edit with STICK/ARROW if needed Always check POSITION FORMAT 3. Select DONE/OK. for the first time to use new device

------Editing Waypoint------• Edit attribute when MARK (select attribute with ARROW button-> ENTER-> DONE) • 2.From the main menu, select Always mark your HOME WAYPOINT MANAGER. (eTrex):main Menu->Find->waypoint- position before you travel >press PAGE-> • Select a waypoint. Select an attribute (such as the name or location). Enter the new information. Select DONE.

GOTO Waypoint Navigating to Waypoint FIND WAYPOINT GOTO • Navigating to a waypoint: – Gives compass bearing, – Distance to point, – Estimated time to get there, based on current rate of travel. Heading: • Once you have a waypoint, you can navigate to it using the – Your moving direction. Bearing: “Goto” command. – The direction from your current • press FIND -> select WAYPOINT -> locat ion t o a dest inat ion. • select GOTO/GO.

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Be Careful with “GOTO” Tracks（航迹） Handheld GPS records a track log while you are moving. You can save these tracks and navigate to them later or go back • Normally directs you in a when you getting lost. straight line—”as-the-crow- flies”. • GPS tells you to go 3.8km at a bearing of 248° true. • Have to look at the map to see what terrain is between the “start” and “end” position.

Managing Track Log Recording A Point About Accuracy Make sure Track Log set to on.

GPSmap 62： Page->Main Menu->Setup->tracks->ENTER Check “track Log” –> Record, Show On Map Check “colour” ->don’t leave as “transparent” eTrex Unit: Page->Main Menu->tracks-> setup->

Do not leave this as “transparent” or no •When you walk into the woods, the sky is covered by trees, results track will show on in not enou gh satellites to get an accurate fix screen. •This is why you ALWAYS need your compass, map, and know where you are on the map. 39

If you get lost…save your track - use Tracback Always Remember!

1. Allow unit to lock on to 4 or more satellites. 2. ALWAYS save your starting point as a waypoint (let’s call it “home”)—write it in your field notebook. 3. Clear the track log & old waypoints before starting a task. 4. Set the odometer/trip to zero. 5. Keep extra batteries and keep GPS warm. 6. Does NOT replace map & compass. Take map & compass with you. 7. Always check/set (according to map reference): Ó Position format Ó Map datum Ó North reference

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The only way to ….. Ñ Always carry a small notebook and pencil (it works in the rain) when you travel in the field. Ñ Mark down your: be comfortable with your GPS Ó bearings, … is to practice, (on your sofa) Ó current position waypoint before you go. …………..practice, (out for a walk) A Notebook and Pencil are always useful…

------What my friends think I do What my mom thinks I do What society thinks I do

What my wife think I do What I think I do What I actually do

Geotag & Geotagging

Ñ What is geotagging Geotagged pictures Ó Geotagging is the process of adding geographical Mingzhi Qu identification metadata to pictures, etc Ph.D. candidate, Dept. of Biology Ó These data usually consist of latitude and { Queen’s University July 2015 longitude coordinates, they can also include altitude, bearing, distance, accuracy data, and place names

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What can Geotag do for field biologist? What Geotag will NOT do? Ñ Provide positions information for your pictures – don ’t need to record coordinator from GPS Ñ Will not:

Ñ Help to document an place or a sample Ó Replace GPS. Ñ Playback your pictures in computer with track/waypoint information Ó Be of any use without a working GPS or a clear view of sky.

Ó Cannot use as marking waypoint Ñ Provide what we call “GPS verification”—proof that work in the field was indeed perf ormed…�

A standard camera with GPS Unit These camera and smartphone Camera GPS Receiver come with GPS too

geographical identification metadata

Make sure your “location service” is ON

Example - iPhone: turn on Location services for your Camera to allow your iPhone to save that data along with your photos. Tap into Settings, and then tap on Privacy. Next, tap on Location Services and make sure they are on. If they are already on, swipe down to the Camera app icon and toggle that switch to ON as well.

Tap into your Photos app, and navigate to the Years, Collections, or Moments views. You’ll see a heading above each section with where those photos were taken. Tap on the location header, and all the pictures from that section will appear on a map.

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If you don’t have a new camera with you…

Record: • Save your picture on your computer Record: Picture, Time • (mac) right click, “get info” Latitude, longitude, SYNC! • (windows)Right click, “properties. Time, and Altitude • Check Latitude and longitude information. • Type these information in google maps, you will Using appropriate software, The latitude and longitude rec orded by your GPS unit see the location of your picture are linked and saved to your photos!

Using Google Earth Pro to measure your wetland Using Google Earth Pro to measure your wetland Mingzhi Qu Ph.D. candidate, Dept. of Biology { Queen’s University July 2015

1. Turn on Track Log Recording 2.Walk along the shoreline GPSmap 62： Page->Main Menu->Setup->tracks->ENTER of the wetland Check “track Log” –> Record, Show On Map Check “colour” ->don’t leave as “transparent” 1. Allow unit to lock on to 4 or more satellites. eTrex Unit: 2. Mark important waypoints Page->Main Menu->tracks-> setup->

Clear the track log & old waypoints before starting a task.

Do not leave this as “transparent” or no track will show on screen.

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3.Download tracks from GPS 6. Open gpx file on Google Earth Pro and measure Devices a. Open “garmin bas em ap ” software b. Connect your Garmin GPS device to your computer c. Click “download from device” d. Click File -> “Save as gpx”

Google Earth Pro is now free for download.

Using your Practice Time smartphone as GPS alterative

Waypoint + track log + geotagged pictures + proper software

= you may use your smartphone Valuable Data and apps to record trails and waypoints. Here’s an example using iPhone apps

Step 1: Download & Run app Step 2: get waypoint

Ñ Giving enough time to get satellite, you Ñ .Download “trail will see your location in Latitude and tracker GPS” from Longitude. app store (free use for a week) Ñ Start recording, you will see waypoint button on top right, but it is gray. Just walk for several meters, you will able to add Ñ Open app, allow app waypoint. to get your current Ñ Once done, click “finish” button - choose location, then tap "save & Quit” “start new trail”

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Step 3: save your trail Step 4: Using google earth pro to analysis your data (1)

Ñ Click results, you will see your recent trail, tap the trail to go full screen Ñ Downloa d google earth pro, after installed, open .kml file with google earth pro, choose preference -> show la t/long ->Universal Transverse Ñ Click export button, choose “.kml” format. now you can sent trail to Mercator(UTM) your email address

Step 4: Using google earth pro to analysis your data (2)

Ñ Right click any waypoint, choose “get info” and you will see you waypoint in UTM format.

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