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Monday, April 8, 2013

Field Activity #8: Navigation with a GPS Unit and Map

Introduction
 

This week’s field activity was a continuation of the last three weeks field activities, which involved creating a navigational map, learning to navigate using that map and a compass, and learning to navigate using only a GPS unit. The purpose of this week’s field activity was to learn how to navigate using a global positioning system (GPS) unit, with the ability to rely on the maps we created. To do this each team was provided with the landscape terrain maps they created (images 1 and 2). Our professor also provided each person with a sheet of paper that contained a series of points, which coincided with the points on our maps, which contained their latitude and longitude (lat/long) coordinate locations (image 3). Every person was also provided with GPS unit (image 4).
Image 1: Navigational map of landscape terrain created in a previous week’s lab
 
Image 2: Reference side of the navigation map created in a previous week’s lab
 
Image 3: Sheet provided to us by our professor with the point’s coordinate location
 
Image 4: GPS unit used for navigation
 
The catch with this week’s activity is that paintballing was incorporated into it. We had used all the methods in the previous week’s activities, and updated our maps to better assist us in the field. Because of this we were very familiar with the tools we had to navigate with, the pros and cons of each of them, and the landscape we were traversing. The purpose of the paintballing was to add a little fun into the mix, and also to encourage us to use our skills wisely and efficiently. The area we navigated had a total of 15 points we were instructed to locate. This time we didn’t have a specific course to navigate through; all six teams simply navigated the points as they felt was most efficient. Navigating from point to point involved matching the lat/long location on the sheet of paper to the lat/long on the GPS unit (image 5). Latitude measures your location north and south, while longitude measures location east and west. Because of this a compass provided in the GPS came in very handy (image 6). Navigating also involved reading the terrain of the landscape we were traversing using our map’s contour lines.
Image 5: Location of lat/long coordinates on the GPS unit
 
Image 6: Compass on GPS used for traversing from point to point
 
As mentioned in the last two week’s activities, as well as Field Activity #4: Distance and Azimuth Survey, before one can use a compass they need to check the magnetic declination of the place they are using it at. Magnetic declination is the angle between compass north and true north. Compass north is the direction the north end of a compass needle points, while true north is the direction along the earth's surface towards the geographic North Pole. Magnetic declination varies both from place to place and with time. In Field Activity #4 we established that the magnetic declination of Eau Claire, WI was 0ᵒ 59’ W. Since 0ᵒ is such a small declination no adjustments to the compass is necessary.
Location
The area where the navigation took place was located on the outskirts of Eau Claire, WI at a place called The Priory (image 7). This land parcel is owned by the University of Wisconsin Eau Claire. This space is used as the university day care center. Because of this restricted areas needed to be added to our navigational maps. We needed to stay a safe distance away from where the children utilize the area for safety reasons regarding them.
Image 7: Locational map of the The Priory in Eau Claire, WI where the navigational activities take place


 
Methods
            Updating Our Maps
Before we could actually begin the navigation part of this activity each group’s maps needed to be updated. This involved adding the course’s navigation points and numbering them, and adding the no shooting zones feature classes. We also needed to make corrections to our maps based on things that could be improved upon to allow for more efficient navigating. Our group was very happy with the first map we created so all we added was the labeled points and the no shooting areas (images 8 and 9).
Image 8: Navigation Map with the course’s navigation points labeled and the no shooting zones added

The red dots with a number and letter above them represent the course’s navigation points and the yellow zones represent the no shooting zones
Image 9: Reference Map with the course’s navigation points labeled and the no shooting zones added

The red dots with a number and letter above them represent the course’s navigation points and the yellow zones represent the no shooting zones
            Getting Ready For The Navigation
To begin this activity we had to haul all the equipment (image 10), which included paintball guns, safety masks, and snow shoes, out to The Priory. We then had to get all the equipment set up in an organized manner (image 11 and 12).  Getting the paintball guns set up involved screwing all the pieces of the gun together and filling the guns with paintballs (image 13).
Image 10: Truck used to haul all the equipment out to The Priory
 
Image 11: Getting all the paintball guns and safety glasses laid out in an organized manner
 
Image 12: Getting the snow shoes out for everyone to take a pair
 
Image 13: Filling the guns with paintballs
 
Each person then had to select a paintball gun, safety mask, and pair of snow shoes (snow shoes were optional for whoever wanted to use them) to use and get themselves prepared for the navigation (images 14 and 15).
Image 14: Getting snow shoes on for whoever chose to wear them
 
Image 15: Set to navigate with all the necessary equipment on
 
           The Navigation
Before beginning the navigation each person needed to turn on the track log on their GPS unit (image 16). Once the track log is turned on the GPS unit begins tracking the route you walk. It is very important to turn this on otherwise you will not end up with any data at the end of your navigation to see how well you traversed from point to point using the lat/long coordinates and your map.
Image 16: Location on the GPS where the track log is turned on and off
 
 
To begin the navigation we all had to start from the same starting point. At that time every team took a separate route of their choosing to get to the first point they were navigating to. We were instructed we needed to wait at least 5 minutes before any shooting began. This was intended for safety reasons and to give each group time to separate from other groups and actually focus on the navigation.
To locate the first point, our group agreed to traverse to, we matched the GPS unit’s lat/long to the lat/long on the sheet of paper (image 17). We also used the map. By using the map we were able to match the elevation we were starting at with the elevation of the first point we were navigating to and use the 2-ft contour lines to determine how far down the hill we needed to go. Using the map also useful because we were able to see which direction we needed to go.  By doing this we could match the compass on the GPS unit with that direction. This was also an efficient method because the lat/long and the compass are located on the same screen on the GPS so you don’t have to switch between screens while navigating (image 18).
Image 17: GPS unit used to navigate from point to point by matching the lat/long to the sheet of paper with lat/long coordinates for each point
 
Image 18: Lat/long coordinates and compass located on same screen for more efficient tracking of directional movement
 
Once a navigation point was reached (image 19) we used the hole punch provided to punch the number point sheets that were provided to us (images 20-22). We also took a way mark on our GPS unit’s.
Image 19: Point marking the navigation courses
 
Image 20: Sheet provided to us to punch with the hole punch once they were navigated to
 
Image 21: Sheet provided to us to punch with the hole punch once they were navigated to
 
Image 22: Sheet provided to us to punch with the hole punch once they were navigated to
 
We continued to navigate the course using this method until class time was over.  At this point we headed by to the starting pint and turned our track logs off. It was important to turn the track log off because otherwise anywhere you went after the navigation activity was over would be recorded. This would make it extremely difficult to know your course when the file was downloaded to the computer. 
          Downloading The Data
Following the navigation activity we needed to get our track logs and way points downloaded from our GPS units to a computer.
To do this I used a program called DNR GPS was that was already installed on the computers (image 23).
Image 23: The DNR GPS program used to download my track log points onto the computer
 
The following steps will lead you through the process that was executed to get the data from my GPS unit onto the computer.
1. First, the GPS unit needed to be connected to the computer with a USB port cord (image 24).
Image 24: GPS unit connected to the computer with a USB port cord
 
2. Then, the “Track” tab was selected (image 25).
Image 25 : “Track” tab selected
 
3. Next, the “Track” tab at the top of the screen was selected and “Download” was chosen (image 26).
Image 26: “Download” was chosen from the “Track” tab dropdown menu
 
4. Then, the computer downloaded the track log data from the GPS unit (image 27).
Image 27: Computer downloaded track log data from GPS unit
 
5. Next, the data was saved into my personal class folder on the W drive as a point shapefile (images 28 -30).
Image 28: “Save to” then “File” is chosen from the “File” dropdown menu
 
Image 29: Navigate to my class folder to save my data as an “ESRI Shapefile”
 
Image 30: Chose to save my data as a “point” shapefile

 
After the track log was downloaded into my class folder I created a geodatabase, in my class folder, using ArcCatalog. Here, I imported my shapefile as feature class. Next, I brought my track log into ArcMap (image 31).
Image 31: Track log brought into ArcMap as a point shapefile

 
After checking the projection of my track log I saw that is was in GCS_WGS_1984 (image 32). It was projected in this coordinate system because that’s what the GPS unit I was using was set up as.
Image 32: Track log downloaded in a GCS_WGS_1984 coordinate system
 
However, the professor instructed us to have our track logs projected in UTM Nad 83. So, I projected my track log into NAD 1983 UTM Zone 15N (images 33 and 34). This is because Eau Claire, WI is located in UTM Zone 15 North.
Image 33: Using the toolbox in ArcMap to project my track log feature class into the correct projection
 
Image 34: NAD 1983 UTM Zone 15N as the chosen projection for my track log

 
Finally, I was able to bring my track log into a new blank map in ArcMap (image 35). By doing this, the data frame for the map was set to this projection due to project on the fly.
Image 35: My track log after the projection
 
After getting my track log data download I needed to get my way point data downloaded. To do this I followed the same steps as outlined above, except selected the appropriate “Waypoint/s” tabs instead (image 36).
Image 36: “Waypoint/s” tabs to be selected to download way point data
 
Now I was able to create maps that depicted the navigation routes for myself, my group, and all groups combined.
Results
Map 1 depicts my individual track log. It shows that overall navigation from point to point was a little curvy. I didn’t walk in a straight line from point to point; however some were better than others. When comparing my final navigation, using both a GPS unit and a map, to my second navigation (map 2) of using only a GPS unit you can similarities in the curviness of my routes.
Map 1: My individual track route and way points from the final navigation activity using a GPS unit and a map
 
Map 2: My individual track route from the second navigation activity using only a GPS unit
 
Map 3 illustrates my groups track logs. Here we can see that overall we followed similar paths. When comparing it to map 4 we can see that this was also the same in comparison to our second navigation. However, there are certain areas in our routes that show times when we split up slightly from one another. This is most vivid in the patch of pine trees in the southwestern section of the map. This is due to our group coming in contact with another group and having a paintball war with one another.
Map 3: My groups track routes and way points in relation to one another’s from the final navigation activity using a GPS unit and a map
 
Map 4: My groups track routes and way points in relation to one another’s from the second navigation activity using only a GPS unit
 
Map 5 shows the routes for all 6 groups.  Team’s routes and way points are depicted through color coding. For example the same color genre from light to dark. Overall, we can see that teams typically followed similar paths. This is the same when compared to map 6.
Map 5: All six groups track routes and way points in relation to each other from the final navigation activity using a GPS unit and a map
 
Map 6: All six groups track routes and way points in relation to each other from the second navigation activity using only a GPS unit
 
Discussion
Overall, we can see similar patterns in how teams routes overlapped one another’s in most cases. Clearly map 5 shows very unstable routes in comparison to map 6. This is because there was no preset path or course to follow. In comparison to the previous weeks routes I didn’t think that the curviness of the paths differed too much. In all, we found the using the map was helpful and found that we rarely used our GPS units at all.
By taking way points on our GPS units we were able to compare them to the course navigation points that were given to us. By comparing how the two lined up in relation to one another we were able to see how technology is not always perfect. Needless to say we didn’t get to all of the points in the time we were for this activity.  Fifteen points was a lot to try to get to in the spread out area we were navigating in 2.5 hours we had to collect them all.
Conclusion
From this activity I learned several important aspects involving navigational skills, keys to success for future navigation, and the pros and cons of the tools involved. Throughout all the navigational activities we’ve conducted this semester I’ve learned the importance of team work. At first working on a team to some may just seems nice to have others around to visit with and make the time more enjoyable. To others who like working alone it may seem annoying and stressful. But what I’ve learned from all these experiences is that working in a team provided us with efficiency and success. Our team worked very well together and everyone brought different strengths to the board. This proved very helpful for certain aspects. For example, one of our team members had very long legs and was good at keeping pace counts in the deep snow. Another team member was very good at tacking locations using the lat/long on the compass.
I also learned that’s it’s very important to be familiar with the gear you are using in the field before going out and trying to accomplish an important task with it. For example, my protective face mask kept fogging up on me. This was extremely annoying, inefficient, and unsafe. I had to keep stopping to take off my mask and wipe the clear area off I looked through. This slowed us down and was very unsafe for in the event there may have been another group around who may have started shooting at us. I also found the snow shoes to pose difficulty. Overall, I thought walking through the snow in them was much easier. However, I kept stepping on the backs of my own snow shoes with the opposite foot and kept falling down. This slowed us down, tired me out, and I kept smacking my shins on branches laying down under the snow. They were also hard to maneuver quickly in. When another team was present and you were trying to get low, hide behind a tree to position yourself in a safe place to shoot at them it was very difficult to do because they were so large and clunky. Finally, I found that the gun got very heavy at by the middle of the navigation. Again, this made me tired and slowed me down. Next time I would choose to put a stack on my gun so I could carry it over my shoulders.
Finally, I learned the importance and pros and cons off all the navigational tools were used. I found that I liked using the map the best. However, I can’t say that the map alone is sufficient. For the last navigation activity we were pretty familiar with the landscape, since we had already navigated two courses in previous weeks. The area was also fairly small, not small in the sense that it was too small for this activity, just in the sense that we could determine our placement on the course in relation to the interstate and the day care center building. This made the last navigation easier than the first two because we could look at the map, determine our position, and remember the terrain of the landscape we were looking for to get to our next way point. Not only that, but the 2-ft contour lines made it very easy to determine ridges, valleys and flat areas. This was especially helpful in reading the landscape. I found that I liked the first method of azimuth and pace count, with the map the best. I thought using azimuth with the compass made the direction we needed to travel very straight forward, and the pace count worked well for determining distance. However, I do think that without having my team members for pace count that I would’ve done as good, or been as happy with the method. Again, this plays into the fact of the high snow and me having short legs. I think that pace count would be much easier when there is no snow on the ground. I also like the azimuth and pace count method because technology can always fail you. So if you started off using a GPS unit and the batteries died you could always rely on your never failing compass and pace count. Overall, I found the GPS unit to be difficult to use alone without a map. The second time we used it with the map it didn’t come in as handy as the first week because we were familiar with the landscape and had our map. I think the GPS unit and map together would complement one another very well in an unknown landscape.
   
 
 
 



 

 


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