Navigation with a GPS

 

 

Introduction

    As a continuation from last weeks exercise, this weeks exercise was to create a GPS navigation course that will be used by the next field methods class. In order to accomplish this task we are to plot points on the navigation map created in exercise 3, navigate to them using techniques learned in last weeks exercise, and enter the points into a Trimble Juno GPS device. Our goal was to make a course that will be difficult for next years class. In order to do this we navigated around the building on the Priory a few times. This makes keeping track of the pace count very inaccurate. However, if they use a map with a decent aerial image they should have no problem locating where to enter the woods to find each of the points.

Study Area

This Priory is located three miles south of the UW- Eau Claire campus. It is 112 acres of multipurpose land that is used as a dormitory for UW- Eau Claire students and a day care for the children of university employees. It contains areas of dense underbrush, steep valleys, and a section with rows of evergreen trees. There is also a few small ponds located in the northeastern corner of the grounds, near Highway 94.

Figure 1  The Priory is located 3 miles south of the UW- Eau Claire campus.

 

 

Methods

Originally, we plotted five points throughout the navigation boundary that we were to navigate to using the skills learned during the previous exercise. After locating our first point, we decided to move the location slightly to the north to make it more difficult for the next class. After finding a suitable location we collected a point using the Trimble Juno GPS unit. After the point was collected, we navigated to the next point. After finding a suitable location for the tree marker we collected another point. This process continued for all five locational points throughout the study area. As you can see below, the location of the actual GPS points is slightly different from original points we were going to collect (Figure 2). After returning to the Cartography lab, we imported the feature class of collected points back into the geodatabase.

Figure 2  The original location of the GPS points versus the actual location of collect points. Some points were moved slightly to make a more difficult course for next years class.

Figure 3  The first of the points marked for next years class. The four other trees will have similar markings to this.  

Results

The following table contains the points and the x,y coordinates in meters based on UTM Zone 15 N coordinate system (Figure 4). Each of the points was mapped in ArcMap and given an appropraite label (Figure 5). Due to time concerns we did not collect the points in the correct order that next years students will have to. We simply located the closest point and set the GPS point.

Figure 4  Table showing the point name, id, and the xy coordinates based on the UTM Zone 15 projection.

 

Figure 5  The location of the points collected overlaid on an aerial.

Conclusion

The location of the points was spread out over a very large area. This will make it difficult for next years students to find the locations accurately. One thing that benefits the students is that there is very little elevation change in this area compared to other areas of the Priory. This should make the process go a lot faster since they will not be required to climb up and down 50 degree slopes to get to their points.