PX4 logs detailed aircraft performance data once the system has been armed until it is disarmed. These flight logs can also be used to analyze performance issues.
Keeping flight logs is a legal requirement in some jurisdictions.
Downloading Logs from the Flight Controller
Analyzing the Logs
Log Analysis using Flight Review explains how to interpret the plots, and can help you to verify/reject the causes of common problems: excessive vibration, poor PID tuning, saturated controllers, imbalanced vehicles, GPS noise, etc.
Flight Log Analysis contains links to information about many other useful logging tools.
Sharing the Log Files for Review by PX4 Developers
The logging system is configured by default to collect sensible logs for use with Flight Review.
Logging may further be configured using the SD Logging parameters. The parameters you are most likely to change are listed below.
|SDLOG_MODE||Logging Mode defines when logging starts and stops.
|SDLOG_PROFILE||Logging profile. Use this to enable less common logging/analysis (e.g. for EKF2 replay, high rate logging for PID & filter tuning, thermal temperature calibration).|
|SDLOG_MISSION||Create very small additional "Mission Log".
This log can not be used with Flight Review, but is useful when you need a small log for geotagging or regulatory compliance.