Vehicle limits

Nodes: nav sim | Module: vehicle | Parameters: Vehicle

The module holds parameters, related to physical limits of the vehicle.

Configuration parameters

  • Vehicle

    Vehicle parameters

    • type Type of vehicle option [CTOL,VTOL]
    • init

      Initial values. Upon power-on procedure, the vehicle will set the corresponding binded mandala fields to defined values. Useful for applying brakes or ignition power on reboot.

      • bind bind
      • value real
    • speed


      • VC Cruise real [m/s] 30

        Airspeed with the maximum LD ratio. Used as cruise airspeed in mission, and in landing procedure as mid-point for speed control for precise landing.

      • VSO Stall with flaps real [m/s] 20

        Minimum allowed airspeed.

      • VSI Stall with no flaps real [m/s]

        This airspeed is used by the auto flaps regulator to apply flaps when the airspeed is close to the parameter value.

      • VFE Max with flaps real [m/s]

        When set, will retract flaps on high speeds to avoid airframe damage.

      • VY Max climbing rate real [m/s]

        When set, used by takeoff procedure to set the commanded airspeed on climbing phase.

      • VNO Normal operation real [m/s]

        Used by landing procedure to limit the maximum airspeed when performing maneuvers.

      • VNE Never exceed real [m/s] 50

        Used as a limit for maximum commanded airspeed.

      • GS Taxi ground speed real [m/s] 1

        Safe ground speed to make maneuvers. Used by taxi procedure for safe taxi speed and by bearing estimator as the minimum ground speed to use velocity rather than yaw angle for bearing.

    • altitude Safe altitude word [m] 100

      The altitude, where it is safe for the vehicle to perform maneuvers. Used by the landing procedure to select the best altitude to start the maneuver.

    • radius Loiter radius word [m] 200

      The default loitering radius. Also used by landing procedure to estimate the landing pattern for precise landing. Should be set to the minimum radius of turn, capable to be performed by vehicle, with the margin of 10%.

    • ld Glide ratio real

      The expected glide ratio of the vehicle. The actual (immediate) LD will be estimated, based on this starting point.

    • climb Maximum climb rate real [m/s] 4.0

      This is the best climb rate that the aircraft can achieve with the max throttle. Used as the limit of climbing rate of the vehicle, used by the TECS controls.

    • sink Maximum descent rate real [m/s] 5.0

      This sets the maximum descent rate that the controller will use. If this value is too large, the aircraft can over-speed on descent. This should be set to a value that can be achieved without exceeding the lower pitch angle limit and without over-speeding the aircraft.

    • acc Maximum acceleration real [m/s^2] 7.0

      This is the maximum vertical acceleration, either up or down, that the controller will use to correct speed or height errors. The controller will limit the slew rate of commanded pitch angle to not to exceed this limit.

    • mtow Max weight word [kg]

      Used by some control loops gains. Although, gain coefficients are estimated, based on the fuel weight. This parameter should reflect the maximum weight of the vehicle, when the fuel capacity is full.

    • fuel

      Vehicle fuel capacity

      • weight Fuel weight word [kg]

        When set, will affect the estimated vehicle weight, used for control loops gains. When equals to zero - means EV (battery powered).

      • endurance Maximum endurance word [min]

        Maximum flight time. Autopilot estimates range and TTL when fuel level sensor is not available. Critical for some built-in safety procedures.

      • thr Throttle to endurance factor real

        Used when the fuel level or fuel rate sensor is not available. The endurance will be estimated based on fuel level, and the fuel rate will be estimated with the throttle control divided by this factor. I.e., cruise throttle, or the endurance parameter value is correct, when the throttle is equal to this parameter value. F.ex., when set to 1 - flying with full throttle will not affect the endurance and low throttle will increase endurance, or when set to 0.5 - the endurance is half the value, when the throttle is full.