Wednesday, April 16, 2014

GIS 1 Lab 3: Introduction to GPS

The purpose of this lab was to become familiar with the basics of using a GPS unit and importing collected data into ArcGIS so it can be displayed in the form of a map. There were multiple objectives to this lab including, creating a geodatabase, placing that geodatabase onto a Trimble Juno GPS unit, learning the basics of the GPS unit, collect point, line and polygon features with the GPS, and finally put that data into ArcGIS to be mapped.
The goal is that at the end of this lab I would be able to use a GPS unit proficiently for collecting data. I would also be able to take that data that I collect and be able to display it in an easily understandable way. This is a very important skill in my opinion and one which I am sure I will use quite a bit in my field of work.
            The first step of the lab was creating the geodatabase. I did this so that when I went out to collect my data the data was placed right into the correct feature class and not just stored as a bunch of random points. The database included point, line and polygon feature classes. I also included an aerial photo of lower campus as my base map. The database is pretty much the base map of campus and the feature classes which are where the point, line, and polygon data will be stored when I use the GPS to collect data.
The next step after I built the database is to put it on the Trimble Juno unit. This is fairly easy to do. I have a folder that includes all of my geodatabase information that I created in step one and I just have to copy that and place it into the memory card of the GPS unit. I did this by connecting the GPS to a computer with USB and then using the Arcpad data manager I copied out my geodatabase files into a folder. Once I have those files all in a folder I just copy and paste that folder onto the GPS unit memory card and then my database is ready to use on the GPS.
The next step was to collect my data. For this lab I was required to collect 3 points of trees and light poles, 1 line feature, and 4 polygons. In the GPS unit I selected which kind of feature I want to collect point, line or polygon and then turn on the satellite so the GPS can read my position. For points I would select my point feature and then go stand where the tree or light pole was and have the GPS record my coordinates and place a vertex. For the polygon I selected the polygon feature and then I started at one corner of the triangle and placed a vertex. I would then walk to the next corner and do the same. I did this 3 times and while I walked it recorded my path between the vertexes. You can do this with any shape area you want. You just have the GPS collect vertexes at corners or ever so often if you are doing a circle and then it will trace where you walk between those points. For the line feature you do the same thing as the polygon feature, you place a vertex where you want the line to start and one where you want to stop and it records the path in between giving you a line.
The final step was to take this data that I collected and make a map of it. This is quite simple to do. All I did is copy the folder from the GPS memory that I had earlier pasted there and paste it back into my folder on the computer. I then used the Arcpad data manager again and check my data back in. I then selected the point, line and polygon files as the files to check back in and when I do this they appear in ArcGIS as points, lines and polygons. They are in the exact same spot on my campus base map as they are in the real world. What you see below in my map, is the data I collected, displayed on a basemap of campus.
Knowing how to do this is very important and a very useful tool. This can be used to display where just about anything is. It can be used for recreational purposes like hunting and fishing or more important things like planning road networks or keeping track of the health of plants. 

Sources: GPS data collected by Michael Bomber 4/16/14

 
Lab 3 map GPS Data of UW-Eau Claire

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