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Full Parameter PDF

Overview

The RAW parameter group (specifically RAW_DATA and RAW_LOG_OPT) configures the recording of unfiltered, low-level sensor information.

Key Concepts

1. GPS Raw Logging (RAW_DATA)

Normally, ArduPilot only logs the calculated Lat/Lon position. Enabling RAW_DATA tells the GPS driver to log the raw satellite measurements (pseudoranges).

  • Purpose: Required for PPK (Post-Processed Kinematics) mapping applications.

2. IMU Raw Logging (RAW_LOG_OPT)

Allows for logging raw IMU samples at very high frequencies (e.g., the full 1kHz or 8kHz rate).

  • Purpose: Used for high-fidelity vibration analysis and tuning the dynamic harmonic notch filters.

Developer Notes

  • Library: libraries/AP_GPS, libraries/AP_InertialSensor.
  • Performance: Enabling raw logging drastically increases the log file size and CPU load. Use only when troubleshooting or performing mapping missions.

RAW_DATA

Default 0
Range 0 5

RAW_DATA: Raw data logging

Description

This parameter enables the logging of raw GNSS satellite observations from the GPS module to the autopilot's DataFlash logs.

Values

Value Meaning
0 Ignore (Disabled)
1 Always log
2 Stop logging when disarmed (SBF/Septentrio only)
5 Only log every five samples (u-blox only)
  • Default: 0

Description

This parameter is essential for PPK (Post-Processing Kinematics).

  • How it works: Instead of just logging the calculated position, it logs the raw "carrier phase" and "pseudorange" data from the satellites.
  • Usage: After a flight, you can use software like RTKLIB or Emlid Studio to process this raw log against a base station log to achieve centimeter-level accuracy for photo geotagging or survey paths.
  • Warning: Enabling this generates much larger log files and increases CPU load. Use a high-speed SD card.

Source Code

ardupilot/libraries/AP_GPS/AP_GPS.cpp

View Source

Raw logging options

RAW_LOG_OPT: Raw logging options

Description

Raw logging options bitmask.

Values

  • Bitmask:

    • Bit 0: Log primary gyro only
    • Bit 1: Log all gyros
    • Bit 2: Post-filter (log data after the low-pass and notch filters)
    • Bit 3: Pre and post-filter (log both raw and filtered data)

  • Default: 0

Description

This parameter controls the high-speed "Raw IMU" logging, which is used for analyzing vibrations and tuning the Harmonic Notch Filter.

  • Usage: Set to 1 to see the raw noise on all gyros. Set to 3 (1 + 2) to see both raw noise and how well your filters are removing it.
  • Warning: High-rate logging creates extremely large log files. Only enable this during tuning flights, then set it back to 0 for regular operation to avoid wearing out your SD card and potentially causing CPU spikes.

Source Code

ardupilot/libraries/AP_InertialSensor/AP_InertialSensor.cpp

View Source
Rate Loop Configuration (RATE) RC Input Configuration (RC)