Computation Section
Subunit Vehicle Routing
 - Google Earth
When the location data is expressed in geographic coordinates, the add-in has an interface to Google Earth. The figure below shows the buttons on the Results worksheet. The Google Earth button appears at the lower right. A similar button appears on the Model worksheet.

google button


Clicking the button initiates a subroutine that creates a program that plots the current solution on a visual replica or the earth provided by the Google Earth application. The picture below shows the first few lines of the program. The program is entirely in column A of the Google worksheet. For the example on this page 649 rows are required for the program. Select the program lines in column A and copy the contents. The proper rows are already selected when the program is displayed. Open a text editor and paste the clip bound to an empty document. Save the document with a name reflecting the model with the suffix .kml. Then double click on the document icon. The Google Earth application automatically runs and displays the current routing solution. Of course the Google Earth application must be installed on your computer. I use version 5.5.

google program


Google Earth


The example illustrates a route through the state capitals in the continental United States (with Washington DC added). The depot for the single vehicle is Washington DC, indicated by a black pushpin. The red pushpins indicate the capital cities.

google map
  We ask Google Earth for a route from Little Rock, Arkansas to Oklahoma City, Oklahoma, and the route shown in purple below is traced. This route compares with the straight line of our Excel generated route because it follows real roads rather than the Great Circle route. Google Earth reports a distance of 336 miles rather than the 297 miles computed by the Great Circle function. Of course the straight line route is shorter than the driving distance along real roads


  Zooming into the Oklahoma City map we see the actual point for the coordinates specified by our data. Apparently the point does not represent the capital building. The balloon shows details of the visit reported by the Excel solution.
google oklahomaÇ
  The interface with Google Earth is an important extension of the Routing add-in. The add-in uses approximate distances to find the optimum sequence of visits. Google Earth displays the routes and uses real time data to find specific routes between pairs of locations.
Return to Top

tree roots

Operations Management / Industrial Engineering
by Paul A. Jensen
Copyright 2004 - All rights reserved