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.

Week 4: Distance and Azimuth Survey

Introduction:
 One cannot always rely on technology to always be functioning perfectly. A backup device or plan is usually a good idea, for example when the first version of apple maps came out I'm sure those iPhone users wish they had a highway map instead. When out surveying landscapes the device you are using may not pick up a signal or just plain run out of battery, without use of that technology it could end up being more effective to go back to the bronze age of geographic surveying, a compass and ruler. For this week's activity we went out and surveyed a 1/4 hectacre plot of land using a TruPulse 360 azimuth, distance and elevation laser and we also used a compass and distance finder.

Methods:
 The study area my group chose to work with was based on the goal of surveying for 50 nodes. We chose a plot of land on 'upper campus' of University of Wisconsin - Eau Claire with a good amount of trees, Frisbee Golf holes, and other miscellaneous items found on a college campus.(Figure 4-1) Our geographical selection was a generally flat surface so we found our origin and got to surveying.
 The TruPulse 360 (Figure 4-2) is capable of emitting an invisible infrared energy pulse that determines the distance by measuring the time it takes for each pulse to travel to the target and back to the TruPulse. Once the measurement is complete, it is displayed on the viewing screen inside of the view hole. The readings can come back as slope distance, azimuth, inclination, horizontal distance and vertical distance. Our group made use of the horizontal distance and azimuth tools the TruPulse provided.  The other method we used was a compass and electronic distance finder. The distance finder was a two piece instrument that sent out a radio signal to the counterpart and returned and measured out the distance, much like the TruPulse, but with only one function and not nearly as fascinating.
 The compass we used was very accurate once adjusted for the declination. Magnetic declination is the angle between the compass north and the true north. Figure 4-3 shows and example of magnetic declination with a positive variation from geographic north. When the declination is affecting your measurements it is important to adjust the compass, there is usually a small screw to fix the issue. Luckily in Eau Claire, WI our declination is very minimal, 0 degrees and 59 min West, so we had only the slightest adjustment to make. The readings off the compass were made while holding the slit in the side of the compass up to one eye, while there you can see both your target and the reading of azimuth.
 Once we decided on the point of origin, just off the corner of Horan Hall, we began surveying points. I used the TruPulse while my partner recorded the measurements I was reading off. We had another group of colleagues alongside of us, they used the compass and distance finder and we later collaborated our efforts in completion of the activity. I used the TruPulse's capabilities to measure the azimuth and horizontal distance to each tree as we recorded across our 1/4 hectacre. Our group only found so many trees, and so we began recording readings to other features, garbage cans, emergency posts, signs, Frisbee Golf holes, and even a sign post.
 Once the surveying was done we entered the data into an Excel file. We had to make a field for the distance, azimuth, point data, and point number. (Figure4-4) Once the file was brought into ArcMap I set up a Geodatabase to house all the data. The table was exported and before I could run the Bearing Distance to Line tool I realized it was necessary to give each data point the point of origin for the surveying. Unfortunately we did not have a definite location for the survey location, as a result I went into ArcMap and opened the Bing Basemap and created a point feature class and created a point at the survey origin. Once the point was created I took the (x,y) data from the origin point and entered it into the Excel file for each point. When the new table was brought into the geodatabase the tool was completed. I ran the tool for each of the surveying that was done, the TruPulse and the compass with the distance finder.

Discussion:
 The accuracy of the results were difficult to compare, as our groups measured together we didn't stand in the same place of origin. This clearly threw our data off by a few degrees and meters here and there, we stood close together but the difference of a foot or two certainly had its toll on the results. (Figure 4-5) When I plotted the points there were issues with making the Bearing Distance to Line tool produce the results in the proper place. The original point of origin I made was done outside of a geodatabase with a non-defined spatial reference. The displacement of the result was close to the proper origin, but not close enough to call accurate to any measure. (Figure4-6)
 When viewing the results of the tool I took into question the accuracy of the entire methodology that we used. As you can see from Figure 4-4 the view that I had for the points on the bottom right corner of the image was not possible, how could I measure through the corner of the building. The other readings, red points, were done closer to the building and they had no issue getting measurements of the points in the bottom right corner of the image. Though none of the points are where they are supposed to be, (Figure 4-7) it is strange to see such a glaring inaccuracy with the TruPulse measurement methodology. The main issue is that the points are not where they are supposed to be, the blue points represent the actual location we were attempting to measure for, the Compass (red) are fairly close to where they are supposed to be considering the distance away from the origin they are. But the TruPulse points (green) are very far off from where they are supposed to be. However, from looking at these maps it is harder to detect the issue that arose, possibly it was measurement communication error, it could be error in the spatial reference. There are a handful of things it could have been.

Conclusion:
  Unfortunately our group was stifled with not enough nodes to measure, we got up to 32 but were unable to get accurate measurements of many others due to interference from previously measured nodes. Also another issue that I had was the inaccuracy of the data at the end of the activity, as I said before I would like to find the origin of this error. This activity was very useful in learning how to use surveying equipment and deducting the best way to record data that is taken. My only wish is that these few labs could be done when it is warm outside, I'm sure that would decrease all error that is arising.

Week 3: Construction of Balloon Mapping Equipment

Introduction:
 Nothing great comes without planning. Michael Jordan planned to be the best and worked harder than anyone else in basketball and succeeded. Man landing on the moon was years in the making. And filling a balloon with a camera apparatus attached to photograph campus is a process that took a few hours with 18 people working on it. The plan this week was to analyze schematics from multiple sources and come up with the best functioning apparatus to capture images of campus from a few hundred feet above ground.

Methods:
 The preparation for the balloon mapping project has gone hand in hand with the high altitude balloon launch (HABL). This week the class separated into separate groups to start producing and planning each necessary step for the launch date, which is still tentative at this point. People in the class split up for tasks such as:

• Construction of the mapping rig
• Construction of the HABL rig
• Parachute testing
• Payload weights of both HABL and mapping rig
• Design of implementing continuous shot on the cameras (for mapping rig)
• Implementation and testing of the tracking device
• Filling the balloon and securing it to each rig

 I was a part of a few of the tasks, there was a fair amount of people doing each one so I was able to help with each one for a fair amount of time. The mapping rig construction was created using a few 2-liter soda bottles. The plans we obtained from multiple online sources, here is one:

http://archive.publiclaboratory.org/download/Grassroots_Mapping_English_2_0.pdf

 This site shows all of the items you will need, along with the steps for creating the rig. The soda bottles were cut in half, keeping the neck and bottle cap section, so we could drop string through the top and have it hold the camera. The camera in the rig is only held by the string, so it dangles in the cut open soda bottle.(Figure 3-4) After completing the rig to hold the camera, we had to find a way to make the camera stay in continuous shot mode. My colleagues created a way to hold down the capture button on the camera with a tight rubber band and a piece of plastic on the top of the capture button. (Figure 3-1)
  While a group was working on the mapping rig there was another weighing each item that could or would be used. The group took weights of each individual item and recorded them into a table in excel. (Figure 3-2) It is important to have a precise weight of the payload so we know how much helium to pump into the balloon that will hold up the mapping rig, or the balloon that will take our camera to the top of our atmosphere.
  The parachute test consisted of a bait tackle box with a 2 lb weight inside of it, the projected weight of our payload. Our group went up to the fourth floor of Phillips Science Building and threw the tackle box out the window. (Figure 3-3) after doing the test three times we were pleased to find out the parachute worked properly.
  While the parachute test was being done another group went out and tested the tracking device. The PocketFinder gps device can send out its coordinates at different settings, every second, four seconds, 30 minutes or hour, we decided it would be best to do it every four seconds. The group went out for a walk and we could keep track of his location using the online application that maps out each point for you. This will be used in the HABL rig to help us find it once it lands.
  The HABL rig is still in development as we are going to wait until closer to the launch date to complete the project. We are planning on using a bait tackle box with a view hole cut into the bottom of it for a clear camera view. The camera will more than likely be in video mode as the pictures would be a little less exciting. The rig will consist of a sealed area with hand warmers which is where the camera will be situated in. The tackle box will be attached by a carabiner and string to the parachute and balloon as it rises. Once the balloon pops the payload will fall and it will be supported by the parachute.
Discussion:
 The project for the day was a good way to observe how well our class worked together on multiple different goals. While some were left with nothing to do because of the size of our class, they were being helpful as they documented the processes and took photos for those who were concentrated on their task at hand.
 I was with the group who did the parachute test and as you can see from the video, the payload picked up speed quickly and hit the ground with some force. I am worried that with the lengthy fall, from hopefully above the troposphere, the payload will reach a relatively high velocity and damage the camera as it hits the ground. If that happens hopefully we can recover the memory card and use that for viewing the video, otherwise it would be devastating if we couldn't.
 The mapping rig is created with a slight surprise, the camera just dangles from the balloon. I understand these plans have been refined and tested a handful of times, but it just seems like the camera will be swaying back and forth in the wind and possibly give us blurry pictures, or possibly some of the horizon and not the ground directly beneath. I wonder if there should be a weight to try and stabilize it as we walk around with the balloon 500 to 1000 ft above ground.

Conclusion:
 I am quite excited to be able to create a mosaic of our campus from a pocket camera. The images will hopefully have a high enough resolution that we can use it for other purposes in class. Our class did a great job of working together and splitting into groups to finish each task. In the class period we completed a mapping rig prototype and set up for the completion of the HABL rig. With all the weights and other testing done we should be ready any day to set our project into action. Later posts will have the results of each project.

Week 2: New and Improved Sandbox Exercise

Introduction:

 Last week was an introduction to the world of 3D modeling; we had the opportunity to go out and create our own terrain and find our own way of surveying the carefully crafted model. The group met, refined, and re-did the previous exercise. We used various interpolation methods to analyze the survey we completed and decided the best way to show what we created.

Methods:

 We started this activity by placing our original data into ArcMap. We did this by using the Add X, Y tool and imported the coordinate pairs and displayed it as a point based feature class. ArcMap is a handy software that provided us with many ways of representing our data by using interpolation methods. We entered our point feature class into 5 different 3D analyst tools; Inverse Distance Weighted (IDW), Natural Neighbors, Kriging, Spline and Triangular Irregular Network (TIN). (see Figures 2-1 through 2-4 on the Photos Page) These methods use our point feature class and form an estimated surface from the points using the z-values. They essentially use the points around each other to form a value, and when in 3D a slope, to satisfy the elevation variations of the points in the feature class. After creating all of these rasters it was possible to bring them into ArcScene and view them in 3D. The best interpolation method was chosen to represent our first survey of the terrain we created, Figure 2-4.

 After analyzing the models that were created it was plain to see there were not enough points collected to properly show all of the terrain's features. This brought an opportunity to go back out to the sandbox and create a new survey method to collect sufficient data to help display the created terrain. After reforming the terrain's features the group concluded on a larger resolution, 5x5 cm. We set up the grid similarily to our first exercise, but this time we stretched a string across the length of the sandbox at intervals of 5 cm. (see Figure 2-5) After pinning down the string across the sandbox we marked up the side walls every 5 cm and used those markings to lay a meter stick across the width of the sandbox. Using that meter stick we took measurements every 5 cm to come out with 22 measurements for each Y coordinate. (see Figure 2-6.) After the completion of our survey we had a total of 1056 points, quite the amount to type into a data table. Once the data was placed into a Microsoft Excel file we brought that table into ArcMap 10, and ran the Add X, Y tool once again, giving our data a spatial extent. The point shapefile was ready to use for running the 3D analyst tools once again.

Discussion:

 Our first survey got the designated job done, however it did not have nearly enough points gathered to give a proper visual representation of our terrain. After running the interpolations for our first survey it was interesting to see the results of each method. The method that best projected our terrain was Spline (see Figure 2-?); it gave our features the most realistic edges and projected the most properly. IDW gave very interesting results, the method works in such that it works as a function of inverse distance, the point measures out a distance and is influenced by certain points in the immediate vicinity. This gives the IDW method a circular look to each point location; (see Figure 2-4) this does not work well if you are looking for a realistic visual representation of the terrain that is surveyed. Though the 3D models worked very well for the points we collected we noticed some bad errors, we created a river in the southern part of the sandbox and as you can see from Figure 2-2 you can barely tell it is there. Also there is a ridge across the northern part of the map that was not meant to be located there, you can compare the photos of our terrain from Figure 1-6 and see there is no ridge in the northern part of the terrain. These errors would not have happened had we known to make smaller measurements; luckily this assignment allowed us to go back and recreate our terrain and make more accurate survey points.

 The second time around we decided to make measurements closer together as stated above, the results were significantly more accurate to what we created. Once the point feature class and the interpolations were done it was fascinating to compare the results. The maps do not look much alike, the new ones were significantly more accurate and when compared to the final product photos you can actually see what we created in our sandbox. Once again I chose the Spline method to represent our terrain as it worked very nicely to give shape to our features created as seen in Figure 2-7.

 If this lab was done again I would bring very fine string to create a full grid on the sandbox to help minimize the error of figuring the location of each measurement. Another adjustment would be to make sure all features do not break the top of the sandbox because it would help alleviate error once again by adjusting measurement methods by having to switch from measuring down and up from the string level. Otherwise the group was able to make the best adjustments for completion of the exercise the second time through.

Conclusion:

 This exercise was a great opportunity to produce a 3D rendition of a real life landscape, look at what you did wrong, and go back, refine, and redo the entire process. The chances to go back and clean up the errors you produced or adjust the surveying techniques you thought were good enough was critical for the success of what we had to accomplish. We didn't know what we were getting into the first time around and essentially 'winged it' so it was great to go back and do it the right way. The group performed very well together, we had no issues distributing the work load and discussing the best way to accomplish what needed to be done. I learned that there is always room for adjustment when doing something and that one way is never the best way of doing it. This activity would be best if it wasn't below freezing outside; otherwise I thought it was a great opportunity to form our own methods of completing the exercise.