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Modules Reference: System

battery_simulator

Source: modules/simulation/battery_simulator

Description

Usage

battery_simulator <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

battery_status

Source: modules/battery_status

Description

The provided functionality includes:

  • Read the output from the ADC driver (via ioctl interface) and publish battery_status.

Implementation

It runs in its own thread and polls on the currently selected gyro topic.

Usage

battery_status <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

camera_feedback

Source: modules/camera_feedback

Description

The camera_feedback module publishes CameraCapture UORB topics when image capture has been triggered.

If camera capture is enabled, then trigger information from the camera capture pin is published; otherwise trigger information at the point the camera was commanded to trigger is published (from the camera_trigger module).

The CAMERA_IMAGE_CAPTURED message is then emitted (by streaming code) following CameraCapture updates. CameraCapture topics are also logged and can be used for geotagging.

Implementation

CameraTrigger topics are published by the camera_trigger module (feedback field set false) when image capture is triggered, and may also be published by the camera_capture driver (with feedback field set true) if the camera capture pin is activated.

The camera_feedback module subscribes to CameraTrigger. It discards topics from the camera_trigger module if camera capture is enabled. For the topics that are not discarded it creates a CameraCapture topic with the timestamp information from the CameraTrigger and position information from the vehicle.

Usage

camera_feedback <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

cdcacm_autostart

Source: drivers/cdcacm_autostart

Description

This module listens on USB and auto-configures the protocol depending on the bytes received. The supported protocols are: MAVLink, nsh, and ublox serial passthrough. If the parameter SYS_USB_AUTO=2 the module will only try to start mavlink as long as the USB VBUS is detected. Otherwise it will spin and continue to check for VBUS and start mavlink once it is detected.

Usage

cdcacm_autostart <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

commander

Source: modules/commander

Description

The commander module contains the state machine for mode switching and failsafe behavior.

Usage

commander <command> [arguments...]
 Commands:
   start
     [-h]        Enable HIL mode

   calibrate     Run sensor calibration
     mag|baro|accel|gyro|level|esc|airspeed Calibration type
     quick       Quick calibration (accel only, not recommended)

   check         Run preflight checks

   arm
     [-f]        Force arming (do not run preflight checks)

   disarm
     [-f]        Force disarming (disarm in air)

   takeoff

   land

   transition    VTOL transition

   mode          Change flight mode
     manual|acro|offboard|stabilized|altctl|posctl|position:slow|auto:mission|au
                 to:loiter|auto:rtl|auto:takeoff|auto:land|auto:precland|ext1
                 Flight mode

   pair

   lockdown
     on|off      Turn lockdown on or off

   set_ekf_origin
     lat, lon, alt Origin Latitude, Longitude, Altitude

   lat|lon|alt   Origin latitude longitude altitude

   poweroff      Power off board (if supported)

   stop

   status        print status info

dataman

Source: modules/dataman

Description

Module to provide persistent storage for the rest of the system in form of a simple database through a C API. Multiple backends are supported:

  • a file (eg. on the SD card)
  • RAM (this is obviously not persistent)

It is used to store structured data of different types: mission waypoints, mission state and geofence polygons. Each type has a specific type and a fixed maximum amount of storage items, so that fast random access is possible.

Implementation

Reading and writing a single item is always atomic.

Usage

dataman <command> [arguments...]
 Commands:
   start
     [-f <val>]  Storage file
                 values: <file>
     [-r]        Use RAM backend (NOT persistent)

 The options -f and -r are mutually exclusive. If nothing is specified, a file
 'dataman' is used

   stop

   status        print status info

dmesg

Source: systemcmds/dmesg

Description

Command-line tool to show bootup console messages. Note that output from NuttX's work queues and syslog are not captured.

Examples

Keep printing all messages in the background:

dmesg -f &

Usage

dmesg <command> [arguments...]
 Commands:
     [-f]        Follow: wait for new messages

esc_battery

Source: modules/esc_battery

Description

This implements using information from the ESC status and publish it as battery status.

Usage

esc_battery <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

gyro_calibration

Source: modules/gyro_calibration

Description

Simple online gyroscope calibration.

Usage

gyro_calibration <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

gyro_fft

Source: modules/gyro_fft

Description

Usage

gyro_fft <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

heater

Source: drivers/heater

Description

Background process running periodically on the LP work queue to regulate IMU temperature at a setpoint.

This task can be started at boot from the startup scripts by setting SENS_EN_THERMAL or via CLI.

Usage

heater <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

i2c_launcher

Source: systemcmds/i2c_launcher

Description

Daemon that starts drivers based on found I2C devices.

Usage

i2c_launcher <command> [arguments...]
 Commands:
   start
     -b <val>    Bus number

   stop

   status        print status info

land_detector

Source: modules/land_detector

Description

Module to detect the freefall and landed state of the vehicle, and publishing the vehicle_land_detected topic. Each vehicle type (multirotor, fixedwing, vtol, ...) provides its own algorithm, taking into account various states, such as commanded thrust, arming state and vehicle motion.

Implementation

Every type is implemented in its own class with a common base class. The base class maintains a state (landed, maybe_landed, ground_contact). Each possible state is implemented in the derived classes. A hysteresis and a fixed priority of each internal state determines the actual land_detector state.

Multicopter Land Detector

ground_contact: thrust setpoint and velocity in z-direction must be below a defined threshold for time GROUND_CONTACT_TRIGGER_TIME_US. When ground_contact is detected, the position controller turns off the thrust setpoint in body x and y.

maybe_landed: it requires ground_contact together with a tighter thrust setpoint threshold and no velocity in the horizontal direction. The trigger time is defined by MAYBE_LAND_TRIGGER_TIME. When maybe_landed is detected, the position controller sets the thrust setpoint to zero.

landed: it requires maybe_landed to be true for time LAND_DETECTOR_TRIGGER_TIME_US.

The module runs periodically on the HP work queue.

Usage

land_detector <command> [arguments...]
 Commands:
   start         Start the background task
     fixedwing|multicopter|vtol|rover|airship Select vehicle type

   stop

   status        print status info

load_mon

Source: modules/load_mon

Description

Background process running periodically on the low priority work queue to calculate the CPU load and RAM usage and publish the cpuload topic.

On NuttX it also checks the stack usage of each process and if it falls below 300 bytes, a warning is output, which will also appear in the log file.

Usage

load_mon <command> [arguments...]
 Commands:
   start         Start the background task

   stop

   status        print status info

logger

Source: modules/logger

Description

System logger which logs a configurable set of uORB topics and system printf messages (PX4_WARN and PX4_ERR) to ULog files. These can be used for system and flight performance evaluation, tuning, replay and crash analysis.

It supports 2 backends:

  • Files: write ULog files to the file system (SD card)
  • MAVLink: stream ULog data via MAVLink to a client (the client must support this)

Both backends can be enabled and used at the same time.

The file backend supports 2 types of log files: full (the normal log) and a mission log. The mission log is a reduced ulog file and can be used for example for geotagging or vehicle management. It can be enabled and configured via SDLOG_MISSION parameter. The normal log is always a superset of the mission log.

Implementation

The implementation uses two threads:

  • The main thread, running at a fixed rate (or polling on a topic if started with -p) and checking for data updates
  • The writer thread, writing data to the file

In between there is a write buffer with configurable size (and another fixed-size buffer for the mission log). It should be large to avoid dropouts.

Examples

Typical usage to start logging immediately:

logger start -e -t

Or if already running:

logger on

Usage

logger <command> [arguments...]
 Commands:
   start
     [-m <val>]  Backend mode
                 values: file|mavlink|all, default: all
     [-x]        Enable/disable logging via Aux1 RC channel
     [-a]        Log 1st armed until shutdown
     [-e]        Enable logging right after start until disarm (otherwise only
                 when armed)
     [-f]        Log until shutdown (implies -e)
     [-t]        Use date/time for naming log directories and files
     [-r <val>]  Log rate in Hz, 0 means unlimited rate
                 default: 280
     [-b <val>]  Log buffer size in KiB
                 default: 12
     [-p <val>]  Poll on a topic instead of running with fixed rate (Log rate
                 and topic intervals are ignored if this is set)
                 values: <topic_name>
     [-c <val>]  Log rate factor (higher is faster)
                 default: 1.0

   on            start logging now, override arming (logger must be running)

   off           stop logging now, override arming (logger must be running)

   trigger_watchdog manually trigger the watchdog now

   stop

   status        print status info

mag_bias_estimator

Source: modules/mag_bias_estimator

Description

Online magnetometer bias estimator.

Usage

mag_bias_estimator <command> [arguments...]
 Commands:
   start         Start the background task

   stop

   status        print status info

manual_control

Source: modules/manual_control

Description

Module consuming manual_control_inputs publishing one manual_control_setpoint.

Usage

manual_control <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

netman

Source: systemcmds/netman

Description

Network configuration manager saves the network settings in non-volatile memory. On boot the update option will be run. If a network configuration does not exist. The default setting will be saved in non-volatile and the system rebooted.

update

netman update is run automatically by a startup script. When run, the update option will check for the existence of net.cfg in the root of the SD Card. It then saves the network settings from net.cfg in non-volatile memory, deletes the file and reboots the system.

save

The save option will save settings from non-volatile memory to a file named net.cfg on the SD Card filesystem for editing. Use this to edit the settings. Save does not immediately apply the network settings; the user must reboot the flight stack. By contrast, the update command is run by the start-up script, commits the settings to non-volatile memory, and reboots the flight controller (which will then use the new settings).

show

The show option will display the network settings in net.cfg to the console.

Examples

$ netman save # Save the parameters to the SD card. $ netman show # display current settings. $ netman update -i eth0 # do an update

Usage

netman <command> [arguments...]
 Commands:
   show          Display the current persistent network settings to the console.

   update        Check SD card for net.cfg and update network persistent network
                 settings.

   save          Save the current network parameters to the SD card.
     [-i <val>]  Set the interface name
                 default: eth0

pwm_input

Source: drivers/pwm_input

Description

Measures the PWM input on AUX5 (or MAIN5) via a timer capture ISR and publishes via the uORB 'pwm_input` message.

Usage

pwm_input <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

rc_update

Source: modules/rc_update

Description

The rc_update module handles RC channel mapping: read the raw input channels (input_rc), then apply the calibration, map the RC channels to the configured channels & mode switches and then publish as rc_channels and manual_control_input.

Implementation

To reduce control latency, the module is scheduled on input_rc publications.

Usage

rc_update <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

replay

Source: modules/replay

Description

This module is used to replay ULog files.

There are 2 environment variables used for configuration: replay, which must be set to an ULog file name - it's the log file to be replayed. The second is the mode, specified via replay_mode:

  • replay_mode=ekf2: specific EKF2 replay mode. It can only be used with the ekf2 module, but allows the replay to run as fast as possible.
  • Generic otherwise: this can be used to replay any module(s), but the replay will be done with the same speed as the log was recorded.

The module is typically used together with uORB publisher rules, to specify which messages should be replayed. The replay module will just publish all messages that are found in the log. It also applies the parameters from the log.

The replay procedure is documented on the System-wide Replay page.

Usage

replay <command> [arguments...]
 Commands:
   start         Start replay, using log file from ENV variable 'replay'

   trystart      Same as 'start', but silently exit if no log file given

   tryapplyparams Try to apply the parameters from the log file

   stop

   status        print status info

send_event

Source: modules/events

Description

Background process running periodically on the LP work queue to perform housekeeping tasks. It is currently only responsible for tone alarm on RC Loss.

The tasks can be started via CLI or uORB topics (vehicle_command from MAVLink, etc.).

Usage

send_event <command> [arguments...]
 Commands:
   start         Start the background task

   stop

   status        print status info

sensor_arispeed_sim

Source: modules/simulation/sensor_airspeed_sim

Description

Usage

sensor_arispeed_sim <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

sensor_baro_sim

Source: modules/simulation/sensor_baro_sim

Description

Usage

sensor_baro_sim <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

sensor_gps_sim

Source: modules/simulation/sensor_gps_sim

Description

Usage

sensor_gps_sim <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

sensor_mag_sim

Source: modules/simulation/sensor_mag_sim

Description

Usage

sensor_mag_sim <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

sensors

Source: modules/sensors

Description

The sensors module is central to the whole system. It takes low-level output from drivers, turns it into a more usable form, and publishes it for the rest of the system.

The provided functionality includes:

  • Read the output from the sensor drivers (SensorGyro, etc.). If there are multiple of the same type, do voting and failover handling. Then apply the board rotation and temperature calibration (if enabled). And finally publish the data; one of the topics is SensorCombined, used by many parts of the system.
  • Make sure the sensor drivers get the updated calibration parameters (scale & offset) when the parameters change or on startup. The sensor drivers use the ioctl interface for parameter updates. For this to work properly, the sensor drivers must already be running when sensors is started.
  • Do sensor consistency checks and publish the SensorsStatusImu topic.

Implementation

It runs in its own thread and polls on the currently selected gyro topic.

Usage

sensors <command> [arguments...]
 Commands:
   start
     [-h]        Start in HIL mode

   stop

   status        print status info

tattu_can

Source: drivers/tattu_can

Description

Driver for reading data from the Tattu 12S 16000mAh smart battery.

Usage

tattu_can <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

temperature_compensation

Source: modules/temperature_compensation

Description

The temperature compensation module allows all of the gyro(s), accel(s), and baro(s) in the system to be temperature compensated. The module monitors the data coming from the sensors and updates the associated sensor_correction topic whenever a change in temperature is detected. The module can also be configured to perform the coeffecient calculation routine at next boot, which allows the thermal calibration coeffecients to be calculated while the vehicle undergoes a temperature cycle.

Usage

temperature_compensation <command> [arguments...]
 Commands:
   start         Start the module, which monitors the sensors and updates the
                 sensor_correction topic

   calibrate     Run temperature calibration process
     [-a]        calibrate the accel
     [-g]        calibrate the gyro
     [-m]        calibrate the mag
     [-b]        calibrate the baro (if none of these is given, all will be
                 calibrated)

   stop

   status        print status info

time_persistor

Source: modules/time_persistor

Description

Writes the RTC time cyclically to a file and reloads this value on startup. This allows monotonic time on systems that only have a software RTC (that is not battery powered). Explicitly setting the time backwards (e.g. via system_time) is still possible.

Usage

time_persistor <command> [arguments...]
 Commands:
   start

   stop

   status        print status info

tune_control

Source: systemcmds/tune_control

Description

Command-line tool to control & test the (external) tunes.

Tunes are used to provide audible notification and warnings (e.g. when the system arms, gets position lock, etc.). The tool requires that a driver is running that can handle the tune_control uorb topic.

Information about the tune format and predefined system tunes can be found here: https://github.com/PX4/PX4-Autopilot/blob/main/src/lib/tunes/tune_definition.desc

Examples

Play system tune #2:

tune_control play -t 2

Usage

tune_control <command> [arguments...]
 Commands:
   play          Play system tune or single note.
     error       Play error tune
     [-t <val>]  Play predefined system tune
                 default: 1
     [-f <val>]  Frequency of note in Hz (0-22kHz)
     [-d <val>]  Duration of note in us
     [-s <val>]  Volume level (loudness) of the note (0-100)
                 default: 40
     [-m <val>]  Melody in string form
                 values: <string> - e.g. "MFT200e8a8a"

   libtest       Test library

   stop          Stop playback (use for repeated tunes)

uxrce_dds_client

Source: modules/uxrce_dds_client

Description

UXRCE-DDS Client used to communicate uORB topics with an Agent over serial or UDP.

Examples

uxrce_dds_client start -t serial -d /dev/ttyS3 -b 921600
uxrce_dds_client start -t udp -h 127.0.0.1 -p 15555

Usage

uxrce_dds_client <command> [arguments...]
 Commands:
   start
     [-t <val>]  Transport protocol
                 values: serial|udp, default: udp
     [-d <val>]  serial device
                 values: <file:dev>
     [-b <val>]  Baudrate (can also be p:<param_name>)
                 default: 0
     [-h <val>]  Agent IP. If not provided, defaults to UXRCE_DDS_AG_IP
                 values: <IP>
     [-p <val>]  Agent listening port. If not provided, defaults to
                 UXRCE_DDS_PRT
     [-n <val>]  Client DDS namespace

   stop

   status        print status info

work_queue

Source: systemcmds/work_queue

Description

Command-line tool to show work queue status.

Usage

work_queue <command> [arguments...]
 Commands:
   start

   stop

   status        print status info