I am no longer sure that a Critical Power Test that I performed was done with the proper Crank Length. Is it possible to extract crank length data from the FIT file to confirm the crank length setting? I used a Garmin Vector 3 and Forerunner 945XT.
I am no longer sure that a Critical Power Test that I performed was done with the proper Crank Length. Is it possible to extract crank length data from the FIT file to confirm the crank length setting? I used a Garmin Vector 3 and Forerunner 945XT.
I unpacked the FIT file using the public FIT SDK from www.thisisant.com. There is a java program that will convert FIT files to CVS.
I then looked in the fit file at the device_info record to find which one was for you power meter. The power meter is device type 11. This is line 14 of the attached file.
antplus_device_type | 11 |
I then looked on that line for the ant_channel_id
ant_channel_id | 353086288 |
Next I moved down to the sensor_profile records to look for a matching ant_channel_id. Line 29. Then I looked along that line to find the crank length.
crank_length | 165 | mm |
Thank you so much.
thx for the tutorial
my SDK version dumps multiple unknows on that line
is crank_length represented as an index value ?
happy & safe sporting
the ANT+ bike power profile encodes the crank length value using the formula: cranklength = 110 + (value / 2).
In your case, 'value' = 110, giving cranklength = 110 + (110 / 2) = 165. The bike power profile encoding allows crank lengths from 110mm to 237 mm to be represented, with 0.5mm resolution.
Could you support me with the same ? I have tried everything but cannot find the cranklength in any of the files that I have converted. I just have 1 single file where I need to see the cranklength so I can get an idea of my history data
share your FIT file (in ZIP format or a direct link to a file sharing service) and i can do it (i think )
crank_length | 167.5 | mm |