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Elevation Data and GPS
In
general, the GPS tracks you record may not be precisely what you want
in a bike ride. Most people take time to linger and chat at some point
in an outing, ride in circles at stop lights, or they answer the call
of nature, without remembering to turn off and on their GPS track
recorder. These behaviors introduce wandering, compact loops or wiggles
in the track data. Still others go hiking, perhaps rock climbing, and
want a bike ride made from the route, forgetting that it involved a few
perfect vertical transitions, staircases etc., which can't be recreated
on the CompuTrainer, of course. We use signal processing techniques to
eliminate discontinuities and undesirable "lingering" sections, and you
can even control the level of detail used in performing some of these
operations.
Most GPS units' elevation data is usually pretty inaccurate, or
"noisy". Small inaccuracies in altitude can lead to some pretty poor,
choppy recreations of the ride. We provide an elevation smoother that
uses signal processing to remove the measurement noise from your
altitude data. The diagram below compares the real GPS altimeter data
to the smoothed data. You can also edit the profile segment by segment,
without having to delete all of your course up to that point, like the
CompuTrainer course building tools do. You save your work to an .xyz
file so you can edit the data another time. Real3D never overwrites
your original GPS data files.
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