Saturday, March 21, 2009

Redwing19 IBA route planning -- GPS track & way points

Way points:
Using the lat,lon coordinates stored in the Google spreadsheet, I created a Google "my map" for each way point by entering its coordinates into the search field.

View Larger Map

After all of the way points were entered, I clicked the "View in Google Earth" link and saved the resulting KML file on my computer. Then, I went to GPS Visualizer to create a GPX file--the format my Garmin Zumo 450 GPS unit understands. I uploaded the KML file to GPS Visualizer and clicked the "Convert" button. I downloaded the resulting GPX file with my way points and transferred it to my Zumo.

For a 1000-mile-in-24-hours endurance ride, I imagine minimizing the need to use my brain to make turn decisions will be desirable, especially in the early morning hours. So, in addition to the way points, I want to have the IBA route also entered into my GPS unit. Most GPS units, certainly all Garmin units I have and seen, will automatically calculate a route between way points. GPS units determine the "best route" based on minimizing distance or time, which is generally what most folks want when going from point A to point B. However, when trying to follow a predetermined route, it can be difficult and time consuming with most GPS units to include necessary intermediate "via-points" to stay on the predetermined track.

So, in addition to the way points, I want to have the IBA route shown on my Zumo. Again, Google to the rescue. Using the same procedure for determining the 120 mile distances between way points, I created a map that begins and ends at the starting point with intermediate points (the white circles) placed along the IBA route. This essentially duplicates the map on the Redwing19 web site.

View Larger Map
Now, using the nifty GMAPtoGPX "bookmarklet" (you can get it here), I created another GPX file that has the track shown on the Google map. I transferred this to my GPS unit allowing me to display both way points and the IBA route.

I can do this.


In previous blog posts, I outlined the procedure for creating way points and tracks in a bit more detail. Click here, here, and here if you'd like to read them.

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