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PropagationEulerianAxes Class

A PropagationStateElement representing the attitude (and angular velocity) of a rigid body with its angular acceleration represented by Euler's equations of motion. Body-fixed coordinates are used for the initial attitude, angular velocity, and moment of inertia matrix.
Inheritance Hierarchy

Namespace:  AGI.Foundation.Propagators
Assembly:  AGI.Foundation.OrbitPropagation (in AGI.Foundation.OrbitPropagation.dll) Version: 22.2.414.0 (22.2.414.0)
Syntax
public class PropagationEulerianAxes : PropagationStateElement

The PropagationEulerianAxes type exposes the following members.

Constructors
  NameDescription
Public methodPropagationEulerianAxes
Initializes a new instance. By default, Earth's inertial frame will be used as the propagation frame, the identity quaternion will be used as the initial attitude, the zero vector will be used as the initial angular velocity, and the identity matrix will be used as the inertia matrix.
Protected methodPropagationEulerianAxes(PropagationEulerianAxes, CopyContext)
Initializes a new instance as a copy of an existing instance.
Public methodPropagationEulerianAxes(String, ReferenceFrame, UnitQuaternion, Cartesian, Matrix3By3Symmetric)
Initializes a new instance.
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Properties
  NameDescription
Public propertyAppliedTorques
Gets a list of the torques applied on the IntegrationAxes. These torques will be converted to the body-fixed frame before they are evaluated.
Public propertyDimension
Gets the number of parameters (per Order) within this element.
(Overrides PropagationStateElementDimension.)
Public propertyIdentification
Gets or sets the string identifying this instance in the overall output.
(Inherited from PropagationStateElement.)
Public propertyIncludeHighestDerivativeInOutput
Gets or sets a value indicating whether to include the derivative computed at each step with the output. If this is true, the output converted from the raw state will contain the derivative associated with the Order of the differential equation.
(Inherited from PropagationStateElement.)
Public propertyInertiaMatrix
Gets or sets the 3x3 inertia matrix of the body on which the torques are applied. This must be defined in the same body-fixed frame that the angular velocity is defined.
Public propertyInitialAngularVelocity
Gets or sets the initial angular velocity expressed in body-fixed axes.
Public propertyInitialAttitudeQuaternion
Gets or sets the initial attitude quaternion that rotates from the IntegrationFrame to the body-fixed reference frame.
Public propertyIntegrationAxes
Gets a Axes which is parameterized on the attitude and angular velocity in the state during integration. This axes is only valid while the NumericalPropagator is running. For more general use, a AxesInterpolator or a RotationalMotionInterpolator should be created from the NumericalPropagationStateHistory produced by the propagator.
Public propertyIntegrationFrame
Gets or sets the inertial ReferenceFrame in which the attitude is defined. By default, the integration frame is set to the InertialFrame of the Earth.
Public propertyIsFrozen
Gets a value indicating whether this object is frozen. A frozen object cannot be modified and an ObjectFrozenException will be thrown if an attempt is made to do so.
(Inherited from DefinitionalObject.)
Public propertyOrder
Gets the order of the differential equation corresponding to this element.
(Overrides PropagationStateElementOrder.)
Public propertyStateParameter
Gets or sets a parameter which represents the state during propagation. In general, users should never need to explicitly set this property. It should only be set when multiple NumericalPropagator objects are running in the same EvaluatorGroup, such as when elements of a state require additional instances of a NumericalPropagator inside their implementation in order to produce their values. In such cases, it may be necessary to distinguish between the state of the exterior propagator and the state of the interior propagator. In these cases, it is up to the user to ensure that both the state and all of its elements are configured with the same parameter. Otherwise, the state will throw an exception when creating its propagator.
(Overrides PropagationStateElementStateParameter.)
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Methods
  NameDescription
Protected methodCheckForSameDefinition(DefinitionalObject)
Checks to determine if another instance has the same definition as this instance and returns if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IsSameDefinition(Object).
(Inherited from PropagationStateElement.)
Protected methodCheckForSameDefinition(PropagationEulerianAxes)
Checks to determine if another instance has the same definition as this instance and returns if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IsSameDefinition(Object).
Protected methodCheckForSameDefinition(PropagationStateElement)
Checks to determine if another instance has the same definition as this instance and returns if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IsSameDefinition(Object).
(Overrides PropagationStateElementCheckForSameDefinition(PropagationStateElement).)
Public methodClone
Clones this object using the specified context.
(Overrides DefinitionalObjectClone(CopyContext).)
Protected methodComputeCurrentDefinitionHashCode
Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the CheckForSameDefinition(DefinitionalObject) method.
(Overrides PropagationStateElementComputeCurrentDefinitionHashCode.)
Public methodEnumerateDependencies
Enumerates the dependencies of this object by calling EnumerateT(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.
(Overrides DefinitionalObjectEnumerateDependencies(DependencyEnumerator).)
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodFreeze
Freezes this object. Further attempts to modify it will result in an ObjectFrozenException.
(Inherited from DefinitionalObject.)
Protected methodFreezeAggregatedObjects
Called by Freeze to also freeze any objects that are considered to be a part of this object. Derived classes which contain additional aggregated objects MUST override this method, call the base implementation, and freeze aggregated objects introduced by the derived class. The objects that need to be frozen in this method are frequently created in this object's constructor and are not settable via properties.
(Overrides DefinitionalObjectFreezeAggregatedObjects.)
Public methodGetConverter
Gets an instance of an output type which can convert the output of propagation back into the native type of this state element. This method is also responsible for configuring the state parameter and the state input indices on any parameterized geometry types used by this element. Each parameterized geometry type will have a static configuration method which will allow it to configure itself in a particular EvaluatorGroup.
(Overrides PropagationStateElementGetConverter(EvaluatorGroup, MotionInt32).)
Public methodGetDefinitionHashCode
Gets a hash code representing the definition of this object.
(Inherited from DefinitionalObject.)
Public methodGetDerivatives
This is used by the NumericalPropagatorDefinition to obtain an instance of a state element evaluator that can compute the derivatives of this element of the state during propagation. It cannot be used outside of a NumericalPropagator as the geometry for the propagation state will be unavailable.
(Overrides PropagationStateElementGetDerivatives(EvaluatorGroup).)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetStateUpdater
Transforms the rotation vector that is used internally to propagate the attitude to avoid the singularity at rotation vector magnitudes near 2*pi radians. If R is the rotation vector and r is its current magnitude, the transformation is (r-2*pi)*R/r -> R and only occurs if r > pi. This transformation ensures that the rotation vector never approaches its singularity.
(Overrides PropagationStateElementGetStateUpdater(EvaluatorGroup).)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Public methodIsSameDefinition
Determines if this object has the same definition as another object.
(Inherited from DefinitionalObject.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Protected methodThrowIfFrozen
Throws ObjectFrozenException if this object IsFrozen. This method should be called from any method or property that modifies this object.
(Inherited from DefinitionalObject.)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
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Remarks
While this class is initialized using UnitQuaternion as an attitude parameterization, the rotation vector is used internally to propagate the attitude. Thus, the NumericalPropagationStateHistory created by propagating this state produces a DateMotionCollection<RotationVectorAngularVelocity> after GetDateMotionCollection<RotationVectorAngularVelocity> is called. This collection can be transformed into a DateMotionCollection<UnitQuaternion, Cartesian> using the static methods available in RotationVectorAngularVelocity. Finally, the DateMotionCollection<UnitQuaternion, Cartesian> can be used to initialize a RotationalMotionInterpolator or AxesInterpolator to provide smooth interpolation of the attitude results.
See Also