Ezigrade (version 2)

Convert Agform-3D™  to Field Level ll file.

 
Ezigrade can import native data directly from an Agform_3D™ *.ag3 file. This allows you to use your favourite designer and use Ezigrade as a conduit to get the design easily to a none Topcon™ product. In this example we are going to show how we can get a design into the Field Level ll system. We have optimised the process as much as possible. The more we automate the process, the easier for the user and hopefully less support calls.
 
We have the following design in Agform_3D™:
 
 
 
It contains 6 sections. In this example the bench mark points also have latitude and longitude's associated with them. This makes it possible to georeference the job and Ezigrade can also extract this internal data.
 
Open up Ezigrade and click on the File -> New menu item. We have a blank job created. Under the File menu make sure we have the correct units being used. ie Meters, Feet or Survey Feet. The data in Agform is stored natively in meters and we need to be able to convert them on the fly when importing the data into Ezigrade. Click on the Import -> Topcon ag3 menu item. You are prompted for a file name - browse to the appropriate *.ag3 file.
 
Ezigrade imports as much data as it understands from the *.ag3 file. The file format is undocumented. At present Ezigrade imports points, triangles, bench marks with latitude/longitude, strings that it recognises. At present we don't try to understand sections, designs etc - only the finished surface etc. If you would like more data extracted please contact us with your requirements. After doing the import we get:
 
 
 
If we have latitude and longitude's defined for the bench marks then Ezigrade can use this data. We suggest you get your designer to set the latitude and longitude for the master bench or BM1 point. If we have a MB or BM1 point then we can use this directly in Ezigrade. To see if we have used any of this data click on File -> Geoid. In this example we have:
 
 
 
 
The Latitude/Longitude of the Master Bench will be filled in. If this is filled then Ezigrade can prefill directly some of the entries in the "Export Trimble GPS" dialog. Now click on Export -> Trimble GPS. Note that the "Lat Lon of MB" is used and the Lat and Lon are filled further down. If these are not prefilled, then close down the dialog. Make sure you have a "MB" point. Now click of File -> Geoid and enter a Lat/Lon value for the Master Bench. We have the following dialog:
 
 
 
Fill in the other values and click on "Create". A *.gps file will be created. We have shown the *.gps in our online viewer. ( http://www.foresoft.com/gpsviewer/browsefile.php )
 
 
 

Agform local data to WGS84 (ie UTM, Google Earth etc)

 
When you import the agform3d data we often seem to get the data in a local coordinate system. Normally a local coordinate system would use a "true north". The simple translation when going to Trimble Field Level2 appears to work. This makes sense as the FL2 system also uses a "true north". Often we want the data to go into a different system. For example Level Guide or Ditch Assist like there data in WGS84. In this case; apart from a translation we also have a rotation to correct for. Scale factor is not normally an issue for reasonable size grading sites!
 
We will show you how to convert the data to WGS84. Back in Agform-3d any benchmarks often have latitude and longitude set. If we have 2 or more bench marks with latitude and longitude then we can convert to WGS84. At present this is a manual process (We promise to automate this in the future).
 
Go back to the stage where we have read in the data from Agform-3d. Close Ezigrade and open the job in CDS3.
 
Now click on View -> Params. We want to display attributes. This is where the import ag3 places the latitude/longitude data. Tick the "Attributes" tick box.
 
 
 
Now display the job. You should be able to see the points that have an associated latitude and longitude.
 
 
 
If you right click on this point you have:
 
 
 
 
In our job we only have two points. If you have two or more points then use the two points that are furthest apart. Make a note of the two point numbers and the associated latitude and longitude. At present Ezigrade is lacking a calculator to show the conversion from latitude / longitude to WGS84. (It is added to the todo list)
 
To get the WGS84 coordinates,  I used the website earthpoint.us and go to the "convert coordinates" menu entry. Enter the latitude / longitude and make a note of the Easting and Northing. Repeat for your second point.
 
 
We can now do the conversion using CDS3. In CDS we need the original 2 points and 2 new points in the new coordinate system. OPen the job in CDS3 and click on Points->Add. We have added in a new point with WGS84 coordinates. Repeat for the second point.
 
 
Now in CDS. We need to select the points that we want to transform. Click on Points -> Select -> Select by Polygon. Draw polygon around all the original data and hit enter to finish the selection. Points should be selected. Now click on Points -> Transform. Fill in the two old points and the new equivalent points.
 
 
You should check the report first and check the scale and rotation makes sense. The job is now in WGS84 coordinates.
 
As mentioned previously we will work at automating this procedure and update this documentation when done.
TODO: Change the footer's content in Project Settings : HTML (CHM) Export : Setup HTML Template and Layout