KalmanModel.java
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package org.orekit.estimation.sequential;
import java.util.List;
import org.orekit.propagation.PropagationType;
import org.orekit.propagation.Propagator;
import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.conversion.OrbitDeterminationPropagatorBuilder;
import org.orekit.propagation.integration.AbstractJacobiansMapper;
import org.orekit.propagation.numerical.JacobiansMapper;
import org.orekit.propagation.numerical.NumericalPropagator;
import org.orekit.propagation.numerical.PartialDerivativesEquations;
import org.orekit.utils.ParameterDriversList;
/** Class defining the process model dynamics to use with a {@link KalmanEstimator}.
* @author Romain Gerbaud
* @author Maxime Journot
* @since 9.2
*/
public class KalmanModel extends AbstractKalmanModel {
/** Kalman process model constructor.
* @param propagatorBuilders propagators builders used to evaluate the orbits.
* @param covarianceMatricesProviders providers for covariance matrices
* @param estimatedMeasurementParameters measurement parameters to estimate
* @param measurementProcessNoiseMatrix provider for measurement process noise matrix
*/
public KalmanModel(final List<OrbitDeterminationPropagatorBuilder> propagatorBuilders,
final List<CovarianceMatrixProvider> covarianceMatricesProviders,
final ParameterDriversList estimatedMeasurementParameters,
final CovarianceMatrixProvider measurementProcessNoiseMatrix) {
// call super constructor
super(propagatorBuilders, covarianceMatricesProviders, estimatedMeasurementParameters,
measurementProcessNoiseMatrix, new JacobiansMapper[propagatorBuilders.size()]);
}
/** {@inheritDoc} */
@Override
protected void updateReferenceTrajectories(final Propagator[] propagators,
final PropagationType pType,
final PropagationType sType) {
// Update the reference trajectory propagator
setReferenceTrajectories(propagators);
// Jacobian mappers
final AbstractJacobiansMapper[] mappers = getMappers();
for (int k = 0; k < propagators.length; ++k) {
// Link the partial derivatives to this new propagator
final String equationName = KalmanEstimator.class.getName() + "-derivatives-" + k;
final PartialDerivativesEquations pde = new PartialDerivativesEquations(equationName, (NumericalPropagator) getReferenceTrajectories()[k]);
// Reset the Jacobians
final SpacecraftState rawState = getReferenceTrajectories()[k].getInitialState();
final SpacecraftState stateWithDerivatives = pde.setInitialJacobians(rawState);
getReferenceTrajectories()[k].resetInitialState(stateWithDerivatives);
mappers[k] = pde.getMapper();
}
// Update Jacobian mappers
setMappers(mappers);
}
/** {@inheritDoc} */
@Override
protected void analyticalDerivativeComputations(final AbstractJacobiansMapper mapper, final SpacecraftState state) {
// does nothing
// numerical method does not require analytical terms calculations
}
}