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

Interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Type Parameters:

T - type of the field elements

All Known Implementing Classes:

FieldAbstractCartesianCost, FieldBoundedCartesianEnergy, FieldCartesianFlightDurationCost, FieldCartesianFuelCost, FieldLogarithmicBarrierCartesianFuel, FieldPenalizedCartesianFuelCost, FieldQuadraticPenaltyCartesianFuel, FieldUnboundedCartesianEnergy, FieldUnboundedCartesianEnergyNeglectingMass

public interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Interface to definite cost function in the frame of Pontryagin's Maximum Principle using Cartesian coordinates. It provides the link between the optimal control and the adjoint variables. This relationship is obtained by maximizing the Hamiltonian. The choice of control vector impacts on it.

Since:

13.0

Author:

Romain Serra

See Also:

• CartesianAdjointDerivativesProvider

Method Summary

Modifier and Type	Method	Description
int	getAdjointDimension()	Getter for adjoint vector dimension.
String	getAdjointName()	Getter for adjoint vector name.
default FieldAdditionalDerivativesProvider<T>	getCostDerivativeProvider(String name)	Get the derivatives provider to be able to integrate the cost function.
default 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.
T	getMassFlowRateFactor()	Getter for mass flow rate factor.
CartesianCost	toCartesianCost()	Method returning equivalent in non-Field.
void	updateFieldAdjointDerivatives(T[] adjointVariables, T mass, T[] adjointDerivatives)	Update the adjoint derivatives if necessary.

Method Details

getAdjointName

String getAdjointName()

Getter for adjoint vector name.

Returns:

adjoint vector name

getAdjointDimension

int getAdjointDimension()

Getter for adjoint vector dimension.

Returns:

adjoint dimension

getMassFlowRateFactor

T getMassFlowRateFactor()

Getter for mass flow rate factor. It is negated and multiplied by the thrust force magnitude to obtain the mass time derivative. The fact that it is a constant means that the exhaust speed is assumed to be independent of time.

Returns:

mass flow rate factor

getFieldThrustAccelerationVector

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

updateFieldAdjointDerivatives

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

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

getFieldEventDetectors

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

Get the detectors needed for propagation.

Parameters:

field - field

Returns:

event detectors

getCostDerivativeProvider

default FieldAdditionalDerivativesProvider<T> getCostDerivativeProvider(String name)

Get the derivatives provider to be able to integrate the cost function.

Parameters:

name - name of cost as additional state variable

Returns:

derivatives provider

Since:

13.0

toCartesianCost

CartesianCost toCartesianCost()

Method returning equivalent in non-Field.

Returns:

cost function for non-Field applications