Flight logs

AstroNav Nano stores mission data as CSV files.

The easy way: AstroNav MC

AstroNav MC reads the logs from the Nano for you. Use Flight logs readout to import and export flights, Mission replay to look at the charts and flight phases, and Data overlay to put the data on your launch video. The rest of this page explains how to work with the CSV files directly.

Leaving USB mode

When using USB configuration mode:

1. Finish editing files.
2. Close applications that are using the drive.
3. Safely eject the AstroNav Nano drive.
4. Wait for the board to leave storage mode.

On Windows, use:

Safely Remove Hardware / Eject

Avoid disconnecting power while a write is active.

EXITUSB

The serial command:

EXITUSB

can also request that the board leave USB storage mode.

Retrieve a flight log

After a completed flight:

1. Confirm landing.
2. Follow your normal recovery procedure.
3. Remove power safely.
4. Disconnect hazardous loads.
5. Connect AstroNav Nano through USB.
6. Open the logs directory.
7. Copy the relevant CSV file.

Flight files use a format similar to:

Flight_XXXXXXXX.csv

Keep the original log unchanged.

Perform analysis on a copy.

Logged data

A flight log may contain:

• Sample counter
• Time in milliseconds
• Power mode
• Flight state
• Pyro state
• Acceleration
• Rotation
• Pressure
• Temperature
• Altitude
• Vertical velocity
• Roll
• Pitch
• Health bits

Reviewing a flight

Pay particular attention to state transitions:

Idle
↓
Boost
↓
Coast
↓
Descent
↓
Landed

The log header tells you what the board decided:

Field	Meaning
APOGEE_TRIGGER	How apogee was found. velocity, drop or peak_hold are normal; baro_descent is the backup for a tumbling or spinning rocket.
PYRO_BLOCKED_REASON	Why the pyro did not fire, or none. For example below_min_height or disabled.
LANDING_TRIGGER	How landing was confirmed, or timeout.
ESTIMATED_HEIGHT_M, HEIGHT_MARGIN_M, ESTIMATED_SPEED_MPS, SPEED_MARGIN_MPS	The flight estimates this flight used, as in Settings.ini. Firmware v1.2.3 and later.

Compare recorded flight behavior with independent mission information where possible.

Review any warnings or fault conditions before drawing conclusions from the data.