aeroworkbook
Glossary
FIT file data
Fit files have 3 types of data. For each type there will be multiple variables such as power, speed etc.Record
This is the time series data, recorded at 1Hz: one value per second.
Lap
One value per lap.
Session
One value for the entire FIT file.
Lap or Out-Back Summary Metrics
In the run data there are many columns. Some are self-explanatory but others are explained below.Dist revs
Lap distance in wheel revolutions.
Av speed
Average speed over the lap = lap distance / lap time.
Yaw
Average wind yaw angle.
Abs Yaw
Average of the absolute yaw angle, where negative values are treated as positive.
Yaw SD
Standard deviation of the 1Hz yaw data over the lap.
Indicator of how gusty the wind is.
Headwind
Headwind speed = wind speed resolved along direction of travel, minus wheel speed.
Headwind SD
Standard deviation of the 1Hz headwind data over the lap. Indicator of how gusty the wind is.
Pressure
Ambient air pressure.
Records
Number of 1Hz samples present in the lap.
Cal
Aero calibration value for the lap.
CdA
Lap CdA calcualted by aerosensor using the run parameters in the Garmin.
Head
Head position measured with aerobody.
Chest
Chest position measured with aerobody.
pXXXX
Average power values. Positive averages power in to the bike, negative is power out.
pRider
Average rider power.
pAero
Aero drag power
pGrav
Gravitational power (power used to propel up hill, or gained from going downhill).
pFric
Rolling resistance power
pKin
Kinetic power, i.e. if bike is accelerating then power is consumed by increase in kinetic energy.
pPdyn
Dynamic pressure power – this is basically average of speed x dynamic pressure. CdA = -pAero / pPdyn.
pXXXCor
_Cor suffix denotes values corrected for specified Used for calculation values under Run parameters.
CdAFinal
This is the CdA value corrected for specified run parameters and for the calculated aero calibration if Auto cal is set to true. If Auto cal is set to false then CdAFinal = CdACor.
Spd Mag Droprate
Aerosensor tries to detect where a magnet pass event is missed by the speed sensor. This is the rate of magnet pass “drops”. Should be zero.
Spd ANT Droprate
Proportion of ANT+ data packets not received by aerosensor from speed sensor. Generally not an issue but useful for debugging. There will always be some dropped packets.
Pwr ANT Droprate
Proportion of ANT+ data packets not received by aerosensor from power meter. Generally not an issue but useful for debugging. There will always be some dropped packets.
Run Data Metrics
These are the values shown near the top of the run worksheet.Laps
Number of laps used for run calculation.
Av Speed
Average speed of all laps.
pRiderCor
Average rider power for all laps.
CdA Final
Final corrected CdA with calculated calibration applied if using Auto cal.
Cal Cor
Corrected calibration factor
CdAF+/-
Maximum lap CdA Final variation from the average, in m2.
CdAF+/-%
Maximum lap CdA Final variation from the average, as percentage of average.
Cal+/-%
Maximum Calibration factor variation from the average, as percentage of average.
Head
Average head position.
Chest
Average chest position.
Yaw
Average wind yaw angle, treating negative values as negative.
Abs Yaw
Average wind yaw angle, treating negative values as positive.
Yaw SD
Wind yaw angle standard deviation.
Headwind
Average headwind speed.
Hwind SD
Headwind standard deviation.
CdA Cor
Corrected CdA but if Auto Cal is used, without calibration factor applied.
