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

Class FieldPenalizedCartesianFuelCost<T extends CalculusFieldElement<T>>

java.lang.Object

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

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

All Implemented Interfaces:

FieldCartesianCost<T>

Direct Known Subclasses:

FieldLogarithmicBarrierCartesianFuel, FieldQuadraticPenaltyCartesianFuel

public abstract class FieldPenalizedCartesianFuelCost<T extends CalculusFieldElement<T>>
extends FieldAbstractCartesianCost<T>

Abstract class for fuel cost with a penalty term proportional to a weight parameter epsilon. This is typically used in a continuation method, starting from epsilon equal to 1 and going towards 0 where the fuel cost is recovered. The point is to enhance convergence. The control vector is the normalized (by the upper bound on magnitude) thrust force in propagation frame. See the following reference: BERTRAND, Régis et EPENOY, Richard. New smoothing techniques for solving bang–bang optimal control problems—numerical results and statistical interpretation. Optimal Control Applications and Methods, 2002, vol. 23, no 4, p. 171-197.

Since:

13.0

Author:

Romain Serra

See Also:

FieldCartesianFuelCost, PenalizedCartesianFuelCost

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	FieldPenalizedCartesianFuelCost(String name, T massFlowRateFactor, T maximumThrustMagnitude, T epsilon)	Constructor.

Method Summary

Modifier and Type	Method	Description
abstract T	evaluateFieldPenaltyFunction(T controlNorm)	Evaluate the penalty term (without the weight), assumed to be a function of the control norm.
T	getEpsilon()	Getter for the penalty weight epsilon.
T	getFieldHamiltonianContribution(T[] adjointVariables, T mass)	Computes the Hamiltonian contribution of the cost function.
protected FieldVector3D<T>	getFieldThrustDirection(T[] adjointVariables)	Computes the direction of thrust.
T	getMaximumThrustMagnitude()	Getter for maximum thrust magnitude.

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

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

getAdjointDimension, getFieldEventDetectors, getFieldThrustAccelerationVector, toCartesianCost, updateFieldAdjointDerivatives

Constructor Detail

FieldPenalizedCartesianFuelCost

protected FieldPenalizedCartesianFuelCost(String name,
                                          T massFlowRateFactor,
                                          T maximumThrustMagnitude,
                                          T epsilon)

Constructor.

Parameters:

name - adjoint name

massFlowRateFactor - mass flow rate factor

maximumThrustMagnitude - maximum thrust magnitude

epsilon - penalty weight

Method Detail

getEpsilon

public T getEpsilon()

Getter for the penalty weight epsilon.

Returns:

epsilon

getMaximumThrustMagnitude

public T getMaximumThrustMagnitude()

Getter for maximum thrust magnitude.

Returns:

maximum thrust

evaluateFieldPenaltyFunction

public abstract T evaluateFieldPenaltyFunction(T controlNorm)

Evaluate the penalty term (without the weight), assumed to be a function of the control norm.

Parameters:

controlNorm - Euclidean norm of control vector

Returns:

penalty function

getFieldThrustDirection

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

Computes the direction of thrust.

Parameters:

adjointVariables - adjoint vector

Returns:

thrust direction

getFieldHamiltonianContribution

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

Computes the Hamiltonian contribution of the cost function.

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

contribution to Hamiltonian