In this section, it will be explained how to configure a whole mission for an airplane, in this case, “Mentor”. The typical phases will be detailed and the guidance for each one of them will be presented.

TAKEOFF

The takeoff phase will be the one where the aircraft goes from the initial to the lift off point.

phase-takeoffThe guidance for this phase will be a “Hold” of three variables: the pitch and roll angles will be kept to zero, while the yaw angle will be kept at the value that the aircraft has when is set on the runway.

Regarding the control loop, there are PIDs in the pitch, roll and yaw control channels, while the throttle has a ramp input as defined in the following figure.

thrust_takeoff1 is the initial value, 0 in this case because the aircraft starts from a standing point. During 0.3 seconds (2), the throttle is increased from the initial to the final value of 0.9 (3).

 CLIMBING

The climbing phase is used to make the airplane reach the cruise altitude after the takeoff.

climb-phaseLine attraction is a value related to how strongly the aircraft tries to reach a path (climb path in this case). This value is commonly between 20 and 40 for airplanes.

Set speed is the speed that will have the airplane during the climb.

Finally, in the “Route” options are configured the parameters that define the path during the climb phase.

  • Flight path angle: angle at which the aircraft climbs.
  • Radius of the circle trajectory made by the aircraft while is climbing.
  • Distance: length from the lift-off point to the beginning of the circular trajectory.
  • Altitude: height to be reached by aircraft during the circular climb.

The following figure is a representation of the climbing route parameters presented previously.

climbing-path

CRUISE

The cruise phase is where the aircraft follows a route marked by a set of waypoints, which are defined by the user in the “Mission” menu.

waypoint-phaseThe parameters are the same as the ones from the climbing phase. It is possible to set a cruise speed, limit the accelerations or set the line attraction parameter. Moreover, there is another option related to the gains used to recover the hover point in a multicopter flight. In this case, the platform configured is an airplane so this one will not be used.

Caution!! When using the Cruise phase, the aircraft will automatically follow the waypoint route. An automation has to be created to make the platform perform in a different way.

HOLD

This phase is used to keep the aircraft at a constant heading, for example, when the radio connection is lost.

hold

When this phase is active, the aircraft flies in a straight line, until another phase is commanded. The variables that are kept at a constant value are the pitch, the roll, and the IAS.

 

LANDING

The landing phase is used to make the aircraft land at a certain airport. Also, when the flight altitude is  too big, this phase contains the parameters which define the route performed by the platform to  descent until an altitude where it can line up with the runway.

landing

The route of the landing phase is shown in the following figure, where each one of the parameters that define it are explained.

landing_route

 

FLARE

The flare is a maneuver made by an aircraft just before the touchdown. Consists on a rise of the nose to decelerate the descent rate and set a proper attitude before touching the ground.

flare

Considering what is wanted in this phase, the guidance to command is a “Hold” of the roll and pitch angle which sets them to zero. Regarding the thrust in this phase, the engines are shut off, so the mode of the controller is “off”.