Week 7: GPS Navigation

Introduction:

This week in class we reprised the navigation activity from the week before with Garmin eTrex GPS units. Our group met up at the UWEC Priory and was given a new course to navigate in the woods, while other groups took the responsibility of navigating the two other courses. Our group’s only tools to navigate were the coordinates and the GPS unit provided for us.

Methods:

In preparation for the activity we had to obtain our GPS units from the University prior to going out to the Priory. When we arrived our group met in the building where we were given our course points. Before starting we were informed on how the GPS units work and how to read the UTM coordinates. The points were given to us in UTM coordinate pairs, for example (617866, 4957994) was our starting point. (Figure 7-1) We had to use the readings on our GPS units to direct us to the starting location and once there we started up our track logs. (Figure 7-2)The track log is a tool on the eTrex GPS unit that records your location once for every time period designated, my unit was set to record my location every 30 seconds.
Once the activity for the day was done we had to upload our groups points to a computer from the eTrex unit. The process was simple, plug it in, open the program, upload the track log and then save it as an ESRI Shapefile in our Priory geodatabase. The new shapefile was easily imported onto our previously made mapping session and there on the computer we could analyze our course. Our instructor created a geodatabase for each member of the class to import their tracklog so everyone could view each others courses. We were instructed to make a final map of each groups track log to see the courses that each group made, they are a bit cluttered but one can see where each group navigated to. (see Figure 7-4.)

Discussion:

Our group was able to navigate through the course with relative ease. We did have an issue at the start of the activity, if you look in Figure 7-X right after our start point 1B we began traversing to the West instead of the proper direction of East to point 2B. When we started we had a disagreement on the proper way to travel when we saw that our second point had a larger x-value in the coordinate pair. We did not immediately realize that the UTM zones increase as they go West, unlike West in values of longitude in other geographic coordinate systems. After navigating the wrong way for a few minutes we reversed our direction and went nearly straight to the second point.

We had no issues getting from one point to another so we decided to try a different approach for navigation; some legs of the expedition we would travel until we got to the proper longitude then traveled north or south, for example traveling from point 4B to 5B (see Figure 7-3). This was a slightly less efficient way to travel but it made for some variability in the activity. Otherwise this activity was done efficiently and successfully with no frost bites or bear sightings, of which there was a chance of both.

Conclusion:

This week’s activity was an enjoyable way to learn how to use a GPS unit with only the coordinates it reads out. With no map it made it more of a challenge to find each point for if we had one, I think it would have been much easier to get from point to point. Compared to last week the activity went by much quicker than using a compass and map. We didn’t need to go step by step with navigating from point to point, we just figured the proper direction to walk in and went that way.

Week 6: Navigation with Map and Compass

Introduction:
 Navigation is an overlooked concept these days, now we have smart phones with a map application that can tell us exactly where to go, where is the fun in that? The University of Wisconsin – Eau Claire Priory was the site for this week’s activity. We would be using the maps we made last week to navigate through the woods to 5 separate points. To begin we would have to learn how to use a compass and map as a method of navigation, after that it was out to the woods to get lost, whether it was literally or in the activity at hand.

Methods:
 Our class met at the UWEC Priory for the navigation activity. I sat with my two group members, Laurel and Phil, and we were each given a printed out copy of the double sided map we made in class the week before. Once the maps were in front of us, we were assigned six points to navigate to in the Priory that were arbitrarily placed by our professor Dr. Hupy we had the 6 points in Course #2. (see Figure 6-1) The objective was to start at the origin and navigate from one point to another using a compass, map and our walking pace.
 The first step in preparing for the navigation activity was to plot out the points provided to us on our maps. We used the UTM grid overlay to plot the points out; once that was done we used the compass to get the azimuth for each leg of our path. To help with finding the azimuth I drew a straight line from one point to the next and used the line as the path to calculate the azimuth. (see Figure 6-2) Our group double checked all the azimuths we measured and found them all to be quite similar, naturally there would be variability due to our individual plotting methods. We then measured the distance between each point to give our group a general idea of the number of paces to take before we would reach the point.
 With the points plotted our group was prepared to go and make our way through the unforgiving undergrowth of the Priory. When we stepped outside we had to pause and decide the proper way of navigating. Our group decided we would have one person stand at the origin point and get his/her azimuth in the proper direction, then send a group member to a temporary marker. We used either a tree or certain distance away which aligned with the proper azimuth. The third group member would then walk, while keeping track of their pace, directly from the origin to the temporary marker. Once the pace keeper reached the temporary marker we would complete the same process over and over again until we reached the destination point on the map. We deducted this method of navigating to do our best to ensure we were walking in a straight line. Once we paced far enough to know we were within 30 meters or so of the destination we would stop and see if we could see it. The destination points were numbered orange flags. To keep track of the flags we had a punch card and there was a puncher attached to each flag we found. As we found each flag we would punch the corresponding number. After we reached the first destination point we adjusted our compass to the proper azimuth and used the flag as the new origin and preformed our navigation method again to later arrive at the next flag. We used the same method for each leg of the navigation exercise and completed the course in due time. The snow was shaken off our boots, the compasses were turned in and we were done.

Discussion:
  At first I was skeptical of the navigation method we came up with as a group. I anticipated navigating very far off course and we would essentially get lost. I was very surprised when we found our first destination point, 6A, directly ahead of us on our first leg. Our pace count was far off what we expected, but the reasons why were very clear. We were ducking under and jumping over trees and bushes and at times had to deviate from our path a small amount to get around some obstructions, nonetheless we found the first destination point with ease. Navigating to the next point, 5A, was also a great success; we were right on course when we found it.
  The third point we had to travel to, 4A, was more of a challenge, it was the largest distance we had to navigate and there was a big problem on the way, a fenced off waste water area. (see Figure 6-2) Before we encountered the fenced off area our plan was to look across and try to find a locator across the way to use as a reference point so we could just walk around the fence and start navigating when we got to it. However the land inside the fence was elevated so we made a quick decision and I hopped the fence and stood atop the ridge and used me as our new reference point. Once atop the ridge I ran across the area, safely along the ridge separating the ponds, and once again stood in as a reference point. Unfortunately once we crossed the area we were thrown off a bit and finding the destination point became a game of hide and seek. As you can see best in Figure 6-3 the point 4A is on the slope, but not distinctly at the top or bottom. Unfortunately we ascended the hill looking for it and then later saw it was much further down the hill than we thought. We climbed that steep hill a few times too many through knee deep snow searching for the destination point. Once there we got back on track and navigated efficiently to the last two points. Unfortunately the tracks from previous groups gave us a path to the next points and spoiled the nature of the activity.

Conclusion:
  Overall I thought our group navigated very efficiently and enjoyed our time trudging through the snow. Once we had the hang of our navigation method it was easy to go about finding each point. Dr. Hupy tried to throw groups off by placing flags in close vicinity to each other, but our group found the right one each time. Next week I will be sure to bring warmer footwear, this week I wore old basketball shoes and a single pair of socks, a very poor choice. Somehow I did not anticipate untouched winter snow out in the woods, and my frozen feet taught me a good lesson. It was nice to stumble upon other group’s tracks at the end so I wasn’t trudging my own path any longer. Besides next week’s GPS usage at the Priory, I think an improvement to this lab would be to make each path the same distance and have groups race to finish. Otherwise I found this lab to be incredibly enjoyable, there is just something about being out with just a map and compass and no other technology to aid you in your navigation. Everybody should have a compass and know how to use it.

Week 5: Development of a Field Navigation Map

Introduction:
 Getting somewhere new to you can be quite difficult if your are without some sort of navigation tool. And a handful of tools are useless unless you have a map of some sort to work with. This week in class we created a map of the UW - Eau Claire Priory. The created map will be used in next weeks Field Methods class as we travel to the priory and are sent out with a list of way-points and their associated coordinates and are required to map them out on foot.

Methods:
 The activity of the week is finding our own pace while walking and making a proper and accurate navigation map. First was the finding of our pace, this included each person in the class to walk 100 meters and keep count of our steps. Being the tallest person in the class I had the smallest pace with 58 strides per 100 meters. This is important to know for when we are out navigating in the woods with no instruments but a compass and map.
 After we all were done determining the proper number for our pace we headed back inside to work on the maps we were tasked to create. We had a good choice of things to include on our maps, 2 ft contours, 5 ft contours, Raster images and DEM's. The map was to be printed off for use in the field so we had them fairly large at 11x17 inches. The map needed to include which way was north, the projection, the coordinate system, a UTM grid, list of data sources and a watermark with your name.
 After creating the map it was time to decide on the best maps for use in the field for the next weeks activity, our group concluded on using my map with the 2 ft contours and we used another members, Phil, for one with imagery and 5 ft contours. The maps were printed on both sides of the paper.

Discussion:
 When the data was brought into ArcGIS it wasn't as easy as choosing what parts you wanted to include in the map, projections were different for almost every shapefile and raster. However, we were given a Point Boundary polygon shapefile that was, well the title of it, the boundary of which we were working in at the Priory. The coordinate system was set to NAD 1983 UTM 15N which gave us a great projection for the Eau Claire area, this gave our map a slight tilt for the UTM coordinates. I would have guessed the gridlines for the map would have been straight up and down the paper but when it was shown in layout view in ArcGIS the gridlines were 'slanted'.
 The next portion of the map I included was the DEM file, it was obtained and used from the USGS seamless server. I laid the DEM on the bottom layer of the map and gave it a color scheme that showed the elevation changes across the priory, as one can see the terrain is sloped fairly heavily in some parts.
 After adding the DEM I chose the 5 ft contours to put onto the map. I thought I had a nice looking map, until I found the 2 ft contour file. The 2 ft contour put the 5 ft to shame with the amount of detail it gave to the contours of the terrain. But of course something had to go wrong, the 2 ft contour was a .dwg file and we were unable to project it properly into the UTM so when it was on the map it would not show up where it was supposed to be. I had mostly been doing 'on the fly' projections where everything essentially falls into place, but the 2 ft contour file was difficult to get into place. To work around this I brought the 2 ft contour into a blank ArcGIS map, then added. The other files with their proper UTM 15N projection. This left the 2 ft contour in the proper place and worked with the DEM in unison to give the map near 3D features. (see Figure 5-1)
 After making the 2 ft contour map I worked on another with the 5 ft contours and an aerial image of the Priory to help us with the navigation aspect of the activity for next week. (see Figure 5-2) This map was simple to make with only 3 files, there were no projection issues as it was pieced together.

Conclusion:
 This week was a good opportunity to give us a chance to create our own map for actual use, the first of which for me. Next week will be very interesting to see how well something that was made from scratch would work in the field. The week was built on the idea of preparing us for the task set forth for us for the next activity, we found our pace count to help prepare us for finding our distances with nothing but a map and compass and created a map to guide our way. The map is the most important piece to any navigation activity and we will see if it has been made accurately enough to keep us from getting lost.