Package org.orekit.control.indirect.adjoint.cost

Class FieldBoundedCartesianEnergy<T extends CalculusFieldElement<T>>

java.lang.Object

org.orekit.control.indirect.adjoint.cost.FieldAbstractCartesianCost<T>

org.orekit.control.indirect.adjoint.cost.FieldBoundedCartesianEnergy<T>

Type Parameters:

T - field type

All Implemented Interfaces:

FieldCartesianCost<T>

public class FieldBoundedCartesianEnergy<T extends CalculusFieldElement<T>>
extends FieldAbstractCartesianCost<T>

Class for bounded energy cost with Cartesian coordinates. An energy cost is proportional to the integral over time of the squared Euclidean norm of the control vector, often scaled with 1/2. This type of cost is not optimal in terms of mass consumption, however its solutions showcase a smoother behavior favorable for convergence in shooting techniques. Here, the control vector is chosen as the thrust force divided by the maximum thrust magnitude and expressed in the propagation frame.

Since:

13.0

Author:

Romain Serra

See Also:

FieldUnboundedCartesianEnergy, BoundedCartesianEnergy

Constructor Summary

Constructors

Constructor	Description
FieldBoundedCartesianEnergy(String name, T massFlowRateFactor, T maximumThrustMagnitude)	Constructor.
FieldBoundedCartesianEnergy(String name, T massFlowRateFactor, T maximumThrustMagnitude, FieldEventDetectionSettings<T> eventDetectionSettings)	Constructor.

Method Summary

Modifier and Type	Method	Description
FieldEventDetectionSettings<T>	getEventDetectionSettings()	Getter for event detection settings.
Stream<FieldEventDetector<T>>	getFieldEventDetectors(Field<T> field)	Get the detectors needed for propagation.
T	getFieldHamiltonianContribution(T[] adjointVariables, T mass)	Computes the Hamiltonian contribution to the cost function.
FieldVector3D<T>	getFieldThrustAccelerationVector(T[] adjointVariables, T mass)	Computes the thrust acceleration vector in propagation frame from the adjoint variables and the mass.
protected FieldVector3D<T>	getFieldThrustDirection(T[] adjointVariables)	Computes the direction of thrust.
protected T	getFieldThrustForceNorm(T[] adjointVariables, T mass)	Computes the Euclidean norm of the thrust force.
T	getMaximumThrustMagnitude()	Getter for maximum thrust magnitude.
BoundedCartesianEnergy	toCartesianCost()	Method returning equivalent in non-Field.
void	updateFieldAdjointDerivatives(T[] adjointVariables, T mass, T[] adjointDerivatives)	Update the adjoint derivatives if necessary.

Methods inherited from class org.orekit.control.indirect.adjoint.cost.FieldAbstractCartesianCost

getAdjointDimension, getAdjointName, getFieldAdjointVelocityNorm, getMassFlowRateFactor

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.orekit.control.indirect.adjoint.cost.FieldCartesianCost

getCostDerivativeProvider

Constructor Detail

FieldBoundedCartesianEnergy

public FieldBoundedCartesianEnergy(String name,
                                   T massFlowRateFactor,
                                   T maximumThrustMagnitude,
                                   FieldEventDetectionSettings<T> eventDetectionSettings)

Constructor.

Parameters:

name - name

massFlowRateFactor - mass flow rate factor

maximumThrustMagnitude - maximum thrust magnitude

eventDetectionSettings - singularity event detection settings

FieldBoundedCartesianEnergy

public FieldBoundedCartesianEnergy(String name,
                                   T massFlowRateFactor,
                                   T maximumThrustMagnitude)

Constructor.

Parameters:

name - name

massFlowRateFactor - mass flow rate factor

maximumThrustMagnitude - maximum thrust magnitude

Method Detail

getMaximumThrustMagnitude

public T getMaximumThrustMagnitude()

Getter for maximum thrust magnitude.

Returns:

maximum thrust

getFieldThrustForceNorm

protected T getFieldThrustForceNorm(T[] adjointVariables,
                                    T mass)

Computes the Euclidean norm of the thrust force.

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

norm of thrust

getFieldEventDetectors

public Stream<FieldEventDetector<T>> getFieldEventDetectors(Field<T> field)

Get the detectors needed for propagation.

Parameters:

field - field

Returns:

event detectors

toCartesianCost

public BoundedCartesianEnergy toCartesianCost()

Method returning equivalent in non-Field.

Returns:

cost function for non-Field applications

getEventDetectionSettings

public FieldEventDetectionSettings<T> getEventDetectionSettings()

Getter for event detection settings.

Returns:

detection settings.

getFieldThrustAccelerationVector

public FieldVector3D<T> getFieldThrustAccelerationVector(T[] adjointVariables,
                                                         T mass)

Computes the thrust acceleration vector in propagation frame from the adjoint variables and the mass.

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

thrust vector

getFieldThrustDirection

protected FieldVector3D<T> getFieldThrustDirection(T[] adjointVariables)

Computes the direction of thrust.

Parameters:

adjointVariables - adjoint vector

Returns:

thrust direction

updateFieldAdjointDerivatives

public void updateFieldAdjointDerivatives(T[] adjointVariables,
                                          T mass,
                                          T[] adjointDerivatives)

Update the adjoint derivatives if necessary.

Parameters:

adjointVariables - adjoint vector

mass - mass

adjointDerivatives - derivatives to update

getFieldHamiltonianContribution

public T getFieldHamiltonianContribution(T[] adjointVariables,
                                         T mass)

Computes the Hamiltonian contribution to the cost function. It equals the Lagrange-form integrand multiplied by -1.

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

contribution to Hamiltonian