PVBuilder.java
- /* Copyright 2002-2019 CS Systèmes d'Information
- * Licensed to CS Systèmes d'Information (CS) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * CS licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.orekit.estimation.measurements.generation;
- import org.hipparchus.geometry.euclidean.threed.Vector3D;
- import org.hipparchus.random.CorrelatedRandomVectorGenerator;
- import org.orekit.estimation.measurements.EstimationModifier;
- import org.orekit.estimation.measurements.ObservableSatellite;
- import org.orekit.estimation.measurements.PV;
- import org.orekit.propagation.SpacecraftState;
- import org.orekit.time.AbsoluteDate;
- import org.orekit.utils.ParameterDriver;
- /** Builder for {@link PV} measurements.
- * @author Luc Maisonobe
- * @since 9.3
- */
- public class PVBuilder extends AbstractMeasurementBuilder<PV> {
- /** Simple constructor.
- * @param noiseSource noise source, may be null for generating perfect measurements
- * @param sigmaPosition theoretical standard deviation on position components
- * @param sigmaVelocity theoretical standard deviation on velocity components
- * @param baseWeight base weight
- * @param satellite satellite related to this builder
- */
- public PVBuilder(final CorrelatedRandomVectorGenerator noiseSource,
- final double sigmaPosition, final double sigmaVelocity,
- final double baseWeight, final ObservableSatellite satellite) {
- super(noiseSource,
- new double[] {
- sigmaPosition, sigmaVelocity
- }, new double[] {
- baseWeight
- }, satellite);
- }
- /** {@inheritDoc} */
- @Override
- public PV build(final SpacecraftState[] states) {
- final ObservableSatellite satellite = getSatellites()[0];
- final double[] sigma = getTheoreticalStandardDeviation();
- final double baseWeight = getBaseWeight()[0];
- final SpacecraftState state = states[satellite.getPropagatorIndex()];
- // create a dummy measurement
- final PV dummy = new PV(state.getDate(), Vector3D.NaN, Vector3D.NaN,
- sigma[0], sigma[1], baseWeight, satellite);
- for (final EstimationModifier<PV> modifier : getModifiers()) {
- dummy.addModifier(modifier);
- }
- // set a reference date for parameters missing one
- for (final ParameterDriver driver : dummy.getParametersDrivers()) {
- if (driver.getReferenceDate() == null) {
- final AbsoluteDate start = getStart();
- final AbsoluteDate end = getEnd();
- driver.setReferenceDate(start.durationFrom(end) <= 0 ? start : end);
- }
- }
- // estimate the perfect value of the measurement
- final double[] pv = dummy.estimate(0, 0, states).getEstimatedValue();
- // add the noise
- final double[] noise = getNoise();
- if (noise != null) {
- pv[0] += noise[0];
- pv[1] += noise[1];
- pv[2] += noise[2];
- pv[3] += noise[3];
- pv[4] += noise[4];
- pv[5] += noise[5];
- }
- // generate measurement
- final PV measurement = new PV(state.getDate(),
- new Vector3D(pv[0], pv[1], pv[2]), new Vector3D(pv[3], pv[4], pv[5]),
- sigma[0], sigma[1], baseWeight, satellite);
- for (final EstimationModifier<PV> modifier : getModifiers()) {
- measurement.addModifier(modifier);
- }
- return measurement;
- }
- }