Traverse Adjustment with LDT Using the Geodimeter 600 & Geotools

Traverse Adjustment with LDT using the Geodimeter 600 & Geotools

The following Geodometer Activity Codes for the traverse points must be used. These codes can be edited in a raw file if needed.

Occupied Stations are 61=0

backsight are 61=1,

foresights are 61=2

side shots are 61=3.

1. Using Geotools create a RAW file from the projects JOB file.

2. Convert the JOB file to a fieldbook (.fbk) file.

3. Remove all Remarks/Comments from the begining of the fieldbook file so it starts like the following

NEZ 3 2268.3979 6496.5433 212.85 "TR3"

UNITS USFOOT DMS

NEZ 2 1985.2209 6374.7458 221.57 "TR2"

STN 3 5.20

BS 2 0

PRISM 5.100

AD VA 1000 0.0005 308.38 88.2351 "TR2"

AD VA 50 158.2955 117.54 90.5723 "TR50"

4. Import the Fieldbook into LDT from the Data Collection/Input menu (AutoDesk Survey must be installed and the Survey Workspace must be active to get this menu option).

5. Open the Survey Toolspace from the Data Collection/Input menu and confirm that the network is populated similar to Figure 1.

Figure 1

This is a closed loop,so field measurements should be made to the begining traverse point. In our work, it started at TR3 and we backsigted TR2.We closed on TR2 with a foresight to TR3.

6. In the Analysis/Figures Menu of the Survey module, Choose, Traverse Loops and then Define Loop. In the Define Loop Dialog box enter the appropriate data for the traverse. Our example is shown in Figure 2.

Note if the dialog box is populated with data, confirm that all required points are listed and that the initial BS & Final FS points are also entered as Occupied Points.

Figure 2

7. Under Analysis/Figures menu, choose Traverse Loops, Adjustment Settings and make sure the loop will be adjusted with the methods you prefer. Conklin uses the settings a shown in Figure 3 as default. These value will vary depending on the required accuracy.

Figure 3

8.Under Analysis/Figures menu, choose Traverse Loops, Check Adjust Loop and the calculation will SIMULATE (You can skip simulation by going directly to Adjust Loop if desired. NOTE THAT ADJUSTING THE LOOP, SIDESHOTS AND FIGURES WILL MOVE AEC POINTS AND UPDATE THE POINT DATABASE). You will be prompted to confirm the Traverse Loop Adjustment Settings. You will thenbe given the error of closure in a text file and you will then decide whether you need the points(sideshots) adjusted. Close the text file to let LDT continue and a new text file will be opened showing the horizontal calculation results. Review & close this text file and LDT will display the vertical results in a 3rd text file. Once the 3 text files are closed you will be prompted to accept, cancel or select a new adjustment.

Figure 4

If the simulation executed without error and the results are not acceptable select cancel and confirm all the loop definition, traverse points and Adjustment settings. You can also click Select Another if you just want to change the Adjustment Settings and rerun the simulation.

It the results are acceptable hit Cancel & Go to the Analysis/Figures menu, choose Traverse Loops and click Adjust loop. The process will repeat and at the end you will be prompted at the command line to Adjust Side shots and Figures. Answer Yes to both. The Survey Toolspace should now display the adjusted data similar to Figure 5. The AEC Points will be adjusted and the Point datatbase will be updated.

Figure 5

!0. Smile when it works like a charm –it’s temperamental sometimes.