# Modules Reference: System
# battery_simulator
Source: modules/simulation/battery_simulator (opens new window)
# Description
# Usage
battery_simulator <command> [arguments...]
Commands:
start
stop
status print status info
# battery_status
Source: modules/battery_status (opens new window)
# 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 (opens new window)
# Description
# Usage
camera_feedback <command> [arguments...]
Commands:
start
stop
status print status info
# commander
Source: modules/commander (opens new window)
# 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|auto:mission|auto:loiter|auto
:rtl|auto:takeoff|auto:land|auto:precland 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 (opens new window)
# 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. If multiple items need to be read/modified atomically, there is
an additional lock per item type via dm_lock.
DM_KEY_FENCE_POINTS and DM_KEY_SAFE_POINTS items: the first data element is a mission_stats_entry_s struct,
which stores the number of items for these types. These items are always updated atomically in one transaction (from
the mavlink mission manager). During that time, navigator will try to acquire the geofence item lock, fail, and will not
check for geofence violations.
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# Description
Simple online gyroscope calibration.
# Usage
gyro_calibration <command> [arguments...]
Commands:
start
stop
status print status info
# gyro_fft
Source: modules/gyro_fft (opens new window)
# Description
# Usage
gyro_fft <command> [arguments...]
Commands:
start
stop
status print status info
# heater
Source: drivers/heater (opens new window)
# 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
# land_detector
Source: modules/land_detector (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window)
# 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 (opens new window) 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 (opens new window)
# 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 (opens new window)
# Description
# Usage
sensor_arispeed_sim <command> [arguments...]
Commands:
start
stop
status print status info
# sensor_baro_sim
Source: modules/simulation/sensor_baro_sim (opens new window)
# Description
# Usage
sensor_baro_sim <command> [arguments...]
Commands:
start
stop
status print status info
# sensor_gps_sim
Source: modules/simulation/sensor_gps_sim (opens new window)
# Description
# Usage
sensor_gps_sim <command> [arguments...]
Commands:
start
stop
status print status info
# sensor_mag_sim
Source: modules/simulation/sensor_mag_sim (opens new window)
# Description
# Usage
sensor_mag_sim <command> [arguments...]
Commands:
start
stop
status print status info
# sensors
Source: modules/sensors (opens new window)
# 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 isSensorCombined, 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
sensorsis started. - Do sensor consistency checks and publish the
SensorsStatusImutopic.
# 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 (opens new window)
# 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 (opens new window)
# 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
[-g] calibrate the gyro
[-a] calibrate the accel
[-b] calibrate the baro (if none of these is given, all will be
calibrated)
stop
status print status info
# tune_control
Source: systemcmds/tune_control (opens new window)
# 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/release/1.14/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 (opens new window)
# 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
[-l] Restrict to localhost (use in combination with
ROS_LOCALHOST_ONLY=1)
[-c] Use custom participant config (profile_name="px4_participant")
[-n <val>] Client DDS namespace
stop
status print status info
# work_queue
Source: systemcmds/work_queue (opens new window)
# Description
Command-line tool to show work queue status.
# Usage
work_queue <command> [arguments...]
Commands:
start
stop
status print status info
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