Drag Estimation

This tool estimates a forward drag function from an ArduCopter log file of a specific flight pattern.
It uses the XKF1 message, which is logged by default, so no changes are required on the drone side.

The flight pattern involves flying backward and forward at different pitch angles while maintaining a consistent altitude and yaw.
The flight should be conducted in low or consistent wind conditions and should be as symmetric as possible, for example;
Flying forward 50m at 5° pitch, flying backwards at -5° pitch, then repeating for the next pitch angle.
It is recommended to use the angle-based “AltHold” mode, but GPS-based modes like “Loiter” can also work.

If no log file is available, the “Load Example” button can be used. Otherwise, follow these steps:

1. Click “Browse” and upload an ArduCopter dataflash log file in .bin format.
2. Use start and end time to trim the data after takeoff and getting into position and before landing.
3. Optionally, configure a pitch offset to counteract imprecise gyro calibration.
4. Enter the drone’s mass and press “Estimate”.
5. To save plots as SVG vector files, right-click on them and select “Download SVG”.