Fun With MapSource

January 2009

by Marc Krouse

I recently led a ride from the RDU airport area to a restaurant in Southern Pines, NC. One of the riders in the group had trouble with a turn, so we doubled back to check out the delay. Nothing much more than disturbed loam and pine straw, but the next day the rider wanted to know where this tricky turn was located. I wasn't positive but I did notice that my Garmin GPS unit had recorded the route as something called a Track

This is a view in MapSource of the Track after I imported it from the GPS unit to my computer. Somewhere on the yellow track paralleling north of US15 was the area where the route went left when the rider was looking right.


A Track is a series of points similar to ‘dropped breadcrumbs' and as we doubled back to smooth out the scattered pine straw, the Track showed ‘double drops' along the way so I could figure out where we pulled over to assist.


The turn is just to the left of the T in Torchwood shown in the image below, and I was able to report back the exact location of the excitement.

While I was poking around Track Properties I noticed quite a bit of interesting data that is recorded during each ‘Index'. You can see this tabulation by double clicking on the Track ID found in the TRACKS Tab. Cool stuff like the clock time of the event, the altitude, the speed at that leg, and the direction traveled. It's fun to page down through the entire route and see the recorded speeds for the entire route.

Even cooler is to select a specific Index [e.g. 594 as shown above] and then check the box for CENTER MAP ON SELECTED ITEM[S] then click OK. It will then display the area of the route when this data point was recorded, highlighted in blue. Looks like I was going 67 mph just after turning onto Torchwood from Underwood. Probably accelerating as shown by indexes 595 and 596.

Another fun thing is to SELECT ALL of the Index points and then use the COPY function to paste the data into text application like Notebook, then import the text file into Excel.

Get rid of any column of data that doesn't make sense for your chart (how about just time and speed) and use the CHART function in Excel to create a nifty analysis of the speeds achieved over the length of the entire ride. Super cool.

It looks like we spent the fair amount of time in the 60 to 80 mph range. Except for a couple of false readings, a cool depiction of a lovely Fall day.

The 120 mph false reading at 9:43:09 seems to have been caused by the track showing an index in the middle of a boat trailer parking lot on Jordan Lake. I have no clue how that happened because we traveled straight along the highway without deviation. GPS mysteries.