Flight Mode Selection

A flight mode defines how the system operates. It can either be flown by the pilot or autopilot. In some flight modes, the autopilot and pilot share different responsibilities (e.g. holding altitude is controlled by the autopilot).

MANUAL

Fixed wing aircraft:

  • MANUAL: The pilot has direct control (via the safety coprocessor) if the ACRO switch is unmapped or off. This is the only mode which overrides the FMU and it provides a safety mechanism which allows full control of throttle, elevator, ailerons and rudder via RC in the event of an FMU firmware malfunction.
  • STABILIZED (aka fly-by-wire): If the ACRO switch is ON, the pilot's inputs are passed as roll and pitch angle commands and direct rudder control. If Sticks are released the Aircraft will level out. Drift from Wind or other sources will not be compensated. This mode requires the FMU to be operating properly. Also note that the ACRO switch has essentially the opposite effect for multirotors.

Multirotors:

Throttle Command is mapped direct to Motor Speed.

  • ACRO: The pilot's inputs are passed as roll, pitch, and yaw rate commands to the autopilot. The Aircraft will not level out after Sticks return to Center. This allows maneuvers like Loops.
  • RATTITUDE The pilot's inputs are passed as roll, pitch, and yaw rate commands to the autopilot at the extreme positions of the sticks. If not the inputs are passed as roll and pitch angle commands and a yaw rate command.
  • STABILIZED The pilot's inputs are passed as roll and pitch angle commands and a yaw rate command. If Sticks are released the Aircraft will level out. Drift from Wind or other sources will not be compensated.

ALTITUDE CONTROL

  • Fixed wing aircraft: When the roll, pitch and yaw inputs (RPY) are all centered, the aircraft will return to straight, level flight and keep its current altitude.
  • Multirotors: Roll, pitch and yaw inputs are as in MANUAL mode. Throttle inputs indicate climb or sink at a predetermined maximum rate. Throttle has a large deadzone.

POSITION CONTROL

  • Fixed wing aircraft: Neutral inputs provide a level flight and will crab against the wind if needed to maintain a straight line.
  • Multirotors Roll controls left-right speed, pitch controls front-back speed. When roll and pitch are all centered (inside deadzone) the multirotor will hold position. Yaw controls yaw rate as in MANUAL mode. Throttle controls climb/descent rate as in ALTCTL mode. WARNING: Do not Land in POSCTL Mode, use Manual Mode to Land.

AUTO

  • HOLD: Holds at the current position (hovers for copter, circles for fixed-wing)
  • RETURN TO LAUNCH (RTL): Return to the home position and land (copter) or circle (fixed-wing).
  • TAKEOFF: Take off and wait for further input.
  • LAND: Land at the location where the mode was engaged.
  • MISSION
    • All system types: All system types: The aircraft obeys the programmed mission sent by the ground control station (GCS). If no mission is received, aircraft will HOVER at current position instead.

OFFBOARD

  • OFFBOARD In this mode the position, velocity or attitude reference / target / setpoint is provided by a companion computer connected via serial cable and MAVLink. The offboard setpoint can be provided by APIs like MAVROS or Dronekit.
© PX4 Dev Team. License: CC BY 4.0           Updated: 2017-07-18 00:54:23

results matching ""

    No results matching ""