Lab 2: Distance-Azimuth Surveys.

Introduction: Technology like rangefinders and total stations are used for surveying purposes. Total stations measure and collect the horizontal distance and azimuth data from one basepoint to another, with the goal of producing a distance-azimuth survey.

Problem/Statement: In this lab, the process of obtaining horizontal distance lines using a rangefinder will be addressed.

Data Collection: For this lab, a Trupluse rangerfinder (Figure 1) was used to collect horizontal distances and azimuths. Using three control points on the University of Wisconsin-Eau Claire campus, horizontal distance and azimuth was collected manually from various features (i.e. lightposts, trees).

Figure 1. The TruPulse Rangefinder

Data Processing: Coordinates on the control points were given to us already in an excel sheet, however we needed to add the data to ArcMap. Using Add XY Data, the excel sheet containing the control points were converted into points, then exported into a shapefile.

Once the horizontal distance and azimuth data was collected, they were entered excel sheets based upon the control point. Once the horizontal distance and azimuth data were entered, data on the XY coordinates were entered each control point’s spread sheet (spreadsheets found in Figure 2). Once the excel data was entered and imported into ArcMap, the Bearing Distance to Line tool was used to convert the excel sheet into line data. Once the line data was created, the Feature Vertices
to Points tool was used to add points at the end of the line data. 

Figure 2. An example of the tabulat data imported into excel. Each control point has its own excel table. 

Results: The data collection and processing yielded the results in Figure 3. In analyzing the accuracy of the lines, they didn’t seem that accurate. For example: the line farthest west at control point 103 was supposed to measure a duck in the stream, however the endpoint seems to be a tad south of the stream. Another line in point 103 yielded inaccurate results, the line moving southeast was supposed to point to a sign on campus north of the Davies Center, however it ends on the Davies Center. 

Figure 3. Distance-Azimuth survey of the UWEC campus. 

 Also, upon further analysis, the data for control points 101 and 102 were entered wrong, so the data for point 101 should be for point 102, and vise-versa. To fix that, one would enter the right coordinates into the appropriate excel sheet, then enter it into an excel sheet.