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

Class FieldUnboundedCartesianEnergyNeglectingMass<T extends CalculusFieldElement<T>>

java.lang.Object

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

Type Parameters:

T - field type

All Implemented Interfaces:

FieldCartesianCost<T>

public class FieldUnboundedCartesianEnergyNeglectingMass<T extends CalculusFieldElement<T>>
extends Object
implements FieldCartesianCost<T>

Class for unbounded energy cost with Cartesian coordinates neglecting the mass consumption. Under this assumption, the mass is constant and there is no need to consider the corresponding adjoint variable. Here, the control vector is chosen as the acceleration given by thrusting, expressed in the propagation frame. This leads to the optimal thrust force being equal to the adjoint velocity vector times the mass.

Since:

13.0

Author:

Romain Serra

Constructor Summary

Constructors

Constructor	Description
FieldUnboundedCartesianEnergyNeglectingMass(String name, Field<T> field)	Constructor.

Method Summary

Modifier and Type	Method	Description
int	getAdjointDimension()	Getter for adjoint vector dimension.
String	getAdjointName()	Getter for adjoint vector name.
T	getFieldHamiltonianContribution(T[] adjointVariables, T mass)	Computes the Hamiltonian contribution of 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.
UnboundedCartesianEnergyNeglectingMass	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 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

getFieldEventDetectors

Constructor Detail

FieldUnboundedCartesianEnergyNeglectingMass

public FieldUnboundedCartesianEnergyNeglectingMass(String name,
                                                   Field<T> field)

Constructor.

Parameters:

name - name

field - field

Method Detail

getAdjointName

public String getAdjointName()

Getter for adjoint vector name.

Specified by:

getAdjointName in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Returns:

name

getAdjointDimension

public int getAdjointDimension()

Getter for adjoint vector dimension. Default is 7 (six for Cartesian coordinates and one for mass).

Specified by:

getAdjointDimension in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Returns:

adjoint dimension

getMassFlowRateFactor

public 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.

Specified by:

getMassFlowRateFactor in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Returns:

mass flow rate factor

getFieldThrustAccelerationVector

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

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

Specified by:

getFieldThrustAccelerationVector in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

thrust vector

updateFieldAdjointDerivatives

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

Update the adjoint derivatives if necessary.

Specified by:

updateFieldAdjointDerivatives in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Parameters:

adjointVariables - adjoint vector

mass - mass

adjointDerivatives - derivatives to update

getFieldHamiltonianContribution

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

Computes the Hamiltonian contribution of the cost function.

Specified by:

getFieldHamiltonianContribution in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Parameters:

adjointVariables - adjoint vector

mass - mass

Returns:

contribution to Hamiltonian

toCartesianCost

public UnboundedCartesianEnergyNeglectingMass toCartesianCost()

Method returning equivalent in non-Field.

Specified by:

toCartesianCost in interface FieldCartesianCost<T extends CalculusFieldElement<T>>

Returns:

cost function for non-Field applications