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Garmin Foot Pod Calibration

89 bytes removed, 22:19, 13 August 2012
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This is a pair of small Windows utilities that analyzes a run and calculates the appropriate recalibration for your [[Best Running Watch|Garmin Foot Pod]] [[FootPod]]. The software is available as a GUI and a Command Line Interface. Note, this is open source and released under [http://www.gnu.org/licenses/gpl.html GPL].
==Device Support==
'''Notes'''
|-
|'''Garmin 310XT'''
|Supported
|
|-|'''Garmin 310XT910XT'''|Supported
|
Supported
 
|
 
 
|-
|'''Garmin 610''' |Supported  |The speed source must be set to footpod, not GPS 
|-
|'''Garmin 405''' |Unsupported |Does not write any speed or distance information from the footpod to the TCX file. 
|-
|'''Garmin 410''' |Unsupported |Does not write any speed or distance information from the footpod to the TCX file. 
|-
|'''Garmin 305''' |Unsupported |Exports from [[Garmin Connect]] contain what looks like speed data from the footpod, but it matches the GPS signal perfectly. 
|}
==How does it work?==
The Garmin devices record your position along with other data such as heart rate every few seconds. If the footpod [[Footpod]] is active, then the speed according to the footpod [[Footpod]] is also recorded. By looking at each position that is recorded, you can work out how far you've traveled and how long it took. That should be the same as the foodpod speed if the GPS is accurate and footpod [[Footpod]] is calibrated.
===Is this different to a Garmin calibration run?===
This is using the same principle as the Garmin calibration run, where you tell the Garmin to calibrate and then run about 1 Kilometer. The calibration run is comparing the GPS distance covered with the footpod [[Footpod]] reported speed. The advantage of this utility is that you can use any run to check the calibration and you can run much further.
===Flaws in the approach===
The biggest flaw in the approach is that it relies on the GPS signal, and GPS is not that accurate itself. If you do not have a GPS signal, such as a treadmill run, then there is no calibration possible and this utility will show that no calibration can be automatically performed. That is because the Garmin recorded data is based on the footpod[[Footpod]], so it's calibrating the footpod [[Footpod]] against itself.
===Getting the best data===
The best run to use for calibration is a run that has the most accurate GPS data. That will be a run that is reasonably straight, as twists and turns tend to reduce the GPS accuracy. A good view of a clear sky can also help a little.
 
===Is there a better way?===
A better approach would be to run a known distance, either on a track or using a known course and calibrate against that known value. The GUI version allows this type of adjustment.
 
===Supported Garmin Devices===
This utility works with the 310XT. The 305 and 405 do not seem to record the data required for calibration.
 
==Installation==
* Download the command line executable from http://fellrnr.com//Utilities/CalibrateFootPod/GarminFootpodCalibrationCLI.exe
* Run the executable ParseTCX.exe passing the full path to the TCX file as a parameter.
** Open a windows explorer window and navigate to the folder with the TCX file.
** Right click on the TCX file and select "Open With…With..." then "Choose Program…Program..."** Click on "Browse…Browse..." and navigate to where you downloaded ParseTCX.exe from.** I would recommend checking the box “Always "Always use the selected program to open this kind of file" so that you can just double click on the TCX file in the future.
** Click OK
* A command window should open and print out a lot of data. At the end you should have a line that says "Multiply your current calibration factor by N" where N is the scaling factor.

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