org.orekit.propagation.semianalytical.dsst

Class DSSTHarvester

java.lang.Object

org.orekit.propagation.AbstractMatricesHarvester

org.orekit.propagation.semianalytical.dsst.DSSTHarvester

All Implemented Interfaces:

MatricesHarvester

public class DSSTHarvester
extends AbstractMatricesHarvester

Harvester between two-dimensional Jacobian matrices and one-dimensional additional state arrays.

Since:

11.1

Author:

Luc Maisonobe, Bryan Cazabonne

Field Summary

Fields inherited from class org.orekit.propagation.AbstractMatricesHarvester

STATE_DIMENSION

Method Summary

Modifier and Type	Method and Description
void	freezeColumnsNames() Freeze the names of the Jacobian columns.
RealMatrix	getB1() Get the Jacobian matrix B1 (B1 = ∂εη/∂Y).
RealMatrix	getB2(SpacecraftState state) Get the Jacobian matrix B2 (B2 = ∂Y/∂Y₀).
RealMatrix	getB3(SpacecraftState state) Get the Jacobian matrix B3 (B3 = ∂Y/∂P).
RealMatrix	getB4() Get the Jacobian matrix B4 (B4 = ∂εη/∂c).
List<String>	getJacobiansColumnsNames() Get the names of the parameters in the matrix returned by MatricesHarvester.getParametersJacobian(org.orekit.propagation.SpacecraftState).
RealMatrix	getParametersJacobian(SpacecraftState state) Get the Jacobian with respect to propagation parameters.
RealMatrix	getStateTransitionMatrix(SpacecraftState state) Extract state transition matrix from state.
void	initializeFieldShortPeriodTerms(SpacecraftState reference) Initialize the short periodic terms for the "field" elements.
void	setReferenceState(SpacecraftState reference) Set up reference state.
void	updateFieldShortPeriodTerms(SpacecraftState reference) Update the short periodic terms for the "field" elements.

Methods inherited from class org.orekit.propagation.AbstractMatricesHarvester

getConversionJacobian, getInitialJacobianColumn, getInitialStateTransitionMatrix, getStmName

Methods inherited from class java.lang.Object

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

Method Detail

getStateTransitionMatrix

public RealMatrix getStateTransitionMatrix(SpacecraftState state)

Extract state transition matrix from state.

Specified by:

getStateTransitionMatrix in interface MatricesHarvester

Overrides:

getStateTransitionMatrix in class AbstractMatricesHarvester

Parameters:

state - spacecraft state

Returns:

state transition matrix, with semantics consistent with propagation, or null if no state transition matrix is available orbit type.

getParametersJacobian

public RealMatrix getParametersJacobian(SpacecraftState state)

Get the Jacobian with respect to propagation parameters.

Specified by:

getParametersJacobian in interface MatricesHarvester

Overrides:

getParametersJacobian in class AbstractMatricesHarvester

Parameters:

state - spacecraft state

Returns:

Jacobian with respect to propagation parameters, or null if there are no parameters

getB1

public RealMatrix getB1()

Get the Jacobian matrix B1 (B1 = ∂εη/∂Y).

B1 represents the partial derivatives of the short period motion with respect to the mean equinoctial elements.

Returns:

the B1 jacobian matrix

getB2

public RealMatrix getB2(SpacecraftState state)

Get the Jacobian matrix B2 (B2 = ∂Y/∂Y₀).

B2 represents the partial derivatives of the mean equinoctial elements with respect to the initial ones.

Parameters:

state - spacecraft state

Returns:

the B2 jacobian matrix

getB3

public RealMatrix getB3(SpacecraftState state)

Get the Jacobian matrix B3 (B3 = ∂Y/∂P).

B3 represents the partial derivatives of the mean equinoctial elements with respect to the estimated propagation parameters.

Parameters:

state - spacecraft state

Returns:

the B3 jacobian matrix

getB4

public RealMatrix getB4()

Get the Jacobian matrix B4 (B4 = ∂εη/∂c).

B4 represents the partial derivatives of the short period motion with respect to the estimated propagation parameters.

Returns:

the B4 jacobian matrix

freezeColumnsNames

public void freezeColumnsNames()

Freeze the names of the Jacobian columns.

This method is called when proagation starts, i.e. when configuration is completed

Specified by:

freezeColumnsNames in class AbstractMatricesHarvester

getJacobiansColumnsNames

public List<String> getJacobiansColumnsNames()

Get the names of the parameters in the matrix returned by MatricesHarvester.getParametersJacobian(org.orekit.propagation.SpacecraftState).

Beware that the names of the parameters are fully known only once all force models have been set up and their parameters properly selected. Applications that retrieve the matrices harvester first and select the force model parameters to retrieve afterwards (but obviously before starting propagation) must take care to wait until the parameters have been set up before they call this method. Calling the method too early would return wrong results.

The names are returned in the Jacobians matrix columns order

Returns:

names of the parameters (i.e. columns) of the Jacobian matrix

initializeFieldShortPeriodTerms

public void initializeFieldShortPeriodTerms(SpacecraftState reference)

Initialize the short periodic terms for the "field" elements.

Parameters:

reference - current mean spacecraft state

updateFieldShortPeriodTerms

public void updateFieldShortPeriodTerms(SpacecraftState reference)

Update the short periodic terms for the "field" elements.

Parameters:

reference - current mean spacecraft state

setReferenceState

public void setReferenceState(SpacecraftState reference)

Set up reference state.

This method is called whenever the global propagation reference state changes. This corresponds to the start of propagation in batch least squares orbit determination or at prediction step for each measurement in Kalman filtering. Its goal is to allow the harvester to compute some internal data. Analytical models like TLE use it to compute analytical derivatives, semi-analytical models like DSST use it to compute short periodic terms, numerical models do not use it at all.

Specified by:

setReferenceState in interface MatricesHarvester

Overrides:

setReferenceState in class AbstractMatricesHarvester

Parameters:

reference - reference state to set