Aero.FixedWing Class

Namespace: Aero

Define fixed-wing aircraft

Since R2021a

Description

An object of the Aero.FixedWing class defines a fixed-wing aircraft. Use this object to model and analyze a fixed-wing aircraft. It contains the static data for the aircraft, such as reference values, coefficients, and deflection angles.

To perform static analysis of fixed-wing aircraft, use this object in conjunction with the Aero.FixedWing.State object. The Aero.FixedWing.State object contains the aircraft information at a particular aircraft state.

For more information on fixed-wing aircraft definitions, see More About.

Class Attributes

Sealed

true

For information on class attributes, see Class Attributes.

Creation

Description

fixedWing = Aero.FixedWing creates a single Aero.FixedWing object with default property values.

fixedWing = Aero.FixedWing(N) creates an N-by-N matrix of Aero.FixedWing objects with default property values.

fixedWing = Aero.FixedWing(M,N,P,...) or Aero.FixedWing([M N P ...]) create an M-by-N-by-P-by-... array of Aero.FixedWing objects with default property values.

fixedWing = Aero.FixedWing(size(A)) creates an Aero.FixedWing object that is the same size as A and all Aero.FixedWing objects.

fixedWing = Aero.FixedWing(__,property,propertyValue) creates an array of Aero.FixedWing objects with property, propertyValue pairs applied to each of the Aero.FixedWing array objects. For a list of properties, see Properties.

Input Arguments

N — Number of fixed-wing objects

scalar

Number of fixed-wing objects, specified as a scalar.

M — Number of fixed-wing objects

scalar

Number of fixed-wing objects, specified as a scalar.

P — Number of fixed-wing objects

scalar

Number of fixed-wing objects, specified as a scalar.

A — Size of fixed-wing object

scalar

Size of fixed-wing object, specified as a scalar.

Properties

Public Properties

UnitSystem — Unit system

'Metric' (default) | 'English (kts)' | 'English (ft/s)' | scalar string | character vector

Unit system, specified as a scalar string or character vector.

Attributes:

GetAccess	public
SetAccess	public

Data Types: string | char

AngleSystem — Angle system

'Radians' (default) | 'Degrees'

Angle system, specified as 'Radians' or 'Degrees'.

Attributes:

GetAccess	public
SetAccess	public

Data Types: string | char

TemperatureSystem — Temperature system

'Kelvin' (default) | 'Celsius' | 'Rankine' | 'Fahrenheit'

Temperature system, specified as 'Kelvin', 'Celsius', 'Rankine', or 'Fahrenheit'.

Attributes:

GetAccess	public
SetAccess	public

Data Types: string | char

ReferenceArea — Reference area

0 (default) | scalar numeric

Reference area, specified as a scalar numeric, commonly denoted as 'S', in units of:

Units	UnitSystem
meters squared (m2)	'Metric'
feet squared (ft2)	'English (kts)' or 'English (ft/s)'

Attributes:

GetAccess	public
SetAccess	public

Data Types: double

ReferenceSpan — Reference span

0 (default) | scalar numeric

Reference span, specified as a scalar numeric, commonly denoted as 'b', in units of:

Units	UnitSystem
meters squared (m)	'Metric'
feet squared (ft)	'English (kts)' or 'English (ft/s)'

Attributes:

GetAccess	public
SetAccess	public

Data Types: double

ReferenceLength — Reference length

0 (default) | scalar numeric

Reference length, specified as a scalar numeric, commonly denoted as 'c', in units of:

Units	UnitSystem
meters squared (m)	'Metric'
feet squared (ft)	'English (kts)' or 'English (ft/s)'

Attributes:

GetAccess	public
SetAccess	public

Data Types: double

Coefficients — Aero.FixedWing.Coefficients class instance

scalar

Aero.FixedWing.Coefficients class instance, specified as a scalar that contains the coefficients defining the fixed-wing aircraft. This object ignores this property if no value is set.

Attributes:

GetAccess	public
SetAccess	public

Data Types: double

DegreesOfFreedom — Degrees of freedom

'6DOF' (default) | '3DOF' | 'PM4' | 'PM6'

Degrees of freedom, specified as a string or character vector.

Degrees of Freedom	Description
'6DOF'	Six degrees of freedom. Describes translational and rotational movement in 3-D space.
'3DOF'	Three degrees of freedom. Describes translational and rotational movement in 2-D space.
'PM4'	Fourth order point-mass. Describes translational movement in 2-D space.
'PM6'	Sixth order point-mass. Describes translational movement in 3-D space.

Attributes:

GetAccess	public
SetAccess	public

Data Types: string | char

Surfaces — Aero.FixedWing.Surface definitions

vector

Aero.FixedWing.Surface definitions, specified as a vector that contains the definitions of the surfaces on the fixed-wing aircraft. The object ignores this property if no value is set.

Attributes:

GetAccess	public
SetAccess	public

Data Types: double

Thrusts — Aero.FixedWing.Thrust definitions

vector

Aero.FixedWing.Thrust definitions, specified as a vector that contains the definitions of the thrust on the fixed-wing aircraft. The object ignores this property if no value is set.

Attributes:

GetAccess	public
SetAccess	public

Data Types:

Protected Properties

AspectRatio — Aspect ratio

scalar numeric

Aspect ratio, specified as a scalar numeric, commonly denoted as 'AR'. This value depends on the values of ReferencedArea and ReferenceSpan, with this equation:

AspectRatio = ReferenceSpan²/ReferencedArea

The object ignores this property if no value is set.

Attributes:

GetAccess	Restricts access
SetAccess	protected

Data Types: double

Methods

Public Methods

analyzeFlyingQualities	Compare aircraft static and dynamic stability against requirement specification
criteriaTable	Construct criteria table for fixed-wing static stability analysis
datcomToFixedWing	Construct fixed-wing aircraft from Digital DATCOM structure
forcesAndMoments	Calculate forces and moments of fixed-wing aircraft
getCoefficient	Get coefficient value for Aero.FixedWing object
getControlStates	Get control states for Aero.FixedWing object
jsbsimToFixedWing	Construct aircraft from JSBSim aircraft configuration file
linearize	Return linear state-space model
nonlinearDynamics	Calculate dynamics of fixed-wing aircraft
saveFixedWingToScript	Save FixedWing aircraft definition to MATLAB script
setCoefficient	Set coefficient value for Aero.FixedWing object
staticStability	Calculate static stability of fixed-wing aircraft
update	Update Aero.FixedWing object

Examples

Create and Use Fixed-Wing Object

Create and set up dynamic behavior and the current state for the fixed-wing object aircraft.

Create a fixed-wing object.

aircraft = Aero.FixedWing()

aircraft = 
  FixedWing with properties:

        ReferenceArea: 0
        ReferenceSpan: 0
      ReferenceLength: 0
         Coefficients: [1×1 Aero.FixedWing.Coefficient]
     DegreesOfFreedom: "6DOF"
             Surfaces: [1×0 Aero.FixedWing.Surface]
              Thrusts: [1×0 Aero.FixedWing.Thrust]
          AspectRatio: NaN
           Properties: [1×1 Aero.Aircraft.Properties]
           UnitSystem: "Metric"
    TemperatureSystem: "Kelvin"
          AngleSystem: "Radians"

To define the aircraft dynamic behavior, set a coefficient for it.

aircraft = setCoefficient(aircraft, "CD", "Zero", 0.27)

aircraft = 
  FixedWing with properties:

        ReferenceArea: 0
        ReferenceSpan: 0
      ReferenceLength: 0
         Coefficients: [1×1 Aero.FixedWing.Coefficient]
     DegreesOfFreedom: "6DOF"
             Surfaces: [1×0 Aero.FixedWing.Surface]
              Thrusts: [1×0 Aero.FixedWing.Thrust]
          AspectRatio: NaN
           Properties: [1×1 Aero.Aircraft.Properties]
           UnitSystem: "Metric"
    TemperatureSystem: "Kelvin"
          AngleSystem: "Radians"

Define the aircraft's current state.

state = Aero.FixedWing.State("Mass", 500)

state = 
  State with properties:

                    Alpha: 0
                     Beta: 0
                 AlphaDot: 0
                  BetaDot: 0
                     Mass: 500
                  Inertia: [3×3 table]
          CenterOfGravity: [0 0 0]
         CenterOfPressure: [0 0 0]
              AltitudeMSL: 0
             GroundHeight: 0
                       XN: 0
                       XE: 0
                       XD: 0
                        U: 50
                        V: 0
                        W: 0
                      Phi: 0
                    Theta: 0
                      Psi: 0
                        P: 0
                        Q: 0
                        R: 0
                   Weight: 4905
              AltitudeAGL: 0
                 Airspeed: 50
              GroundSpeed: 50
               MachNumber: 0.1469
             BodyVelocity: [50 0 0]
           GroundVelocity: [50 0 0]
                       Ur: 50
                       Vr: 0
                       Wr: 0
          FlightPathAngle: 0
              CourseAngle: 0
     InertialToBodyMatrix: [3×3 double]
     BodyToInertialMatrix: [3×3 double]
         BodyToWindMatrix: [3×3 double]
         WindToBodyMatrix: [3×3 double]
    BodyToStabilityMatrix: [3×3 double]
    StabilityToBodyMatrix: [3×3 double]
          DynamicPressure: 1.5312e+03
              Environment: [1×1 Aero.Aircraft.Environment]
            ControlStates: [1×0 Aero.Aircraft.ControlState]
         OutOfRangeAction: "Limit"
         DiagnosticAction: "Warning"
               Properties: [1×1 Aero.Aircraft.Properties]
               UnitSystem: "Metric"
        TemperatureSystem: "Kelvin"
              AngleSystem: "Radians"

Calculate the forces and moments on the aircraft.

[F, M] = forcesAndMoments(aircraft, state)

F = 3×1

           0
           0
        4905

M = 3×1

     0
     0
     0

Limitations

You cannot subclass Aero.FixedWing.

More About

Fixed-Wing Definitions

The FixedWing object holds the main definition of a fixed-wing aircraft. The object has a main set of body coefficients defined by these tables:

Body Coefficients in Wind Frame

Body Coefficients	Wind Frame
	Zero	U	Alpha	AlphaRate	Theta	Beta	BetaRate	Phi	Psi
CD
CY
CL
CI
Cm
Cn

Body Coefficients in Body Frame

Body Coefficients	Wind Frame
	Zero	U	Alpha	AlphaRate	Theta	Beta	BetaRate	Phi	Psi
CX
CY
CZ
CI
Cm
Cn

Version History

Introduced in R2021a