SpacecraftState.java
- /* Copyright 2002-2020 CS GROUP
- * Licensed to CS GROUP (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.propagation;
- import java.io.Serializable;
- import java.util.ArrayList;
- import java.util.Collections;
- import java.util.HashMap;
- import java.util.List;
- import java.util.Map;
- import java.util.stream.Stream;
- import org.hipparchus.analysis.interpolation.HermiteInterpolator;
- import org.hipparchus.exception.LocalizedCoreFormats;
- import org.hipparchus.exception.MathIllegalStateException;
- import org.hipparchus.geometry.euclidean.threed.Rotation;
- import org.hipparchus.geometry.euclidean.threed.Vector3D;
- import org.hipparchus.util.FastMath;
- import org.orekit.attitudes.Attitude;
- import org.orekit.attitudes.LofOffset;
- import org.orekit.errors.OrekitException;
- import org.orekit.errors.OrekitIllegalArgumentException;
- import org.orekit.errors.OrekitIllegalStateException;
- import org.orekit.errors.OrekitMessages;
- import org.orekit.frames.Frame;
- import org.orekit.frames.LOFType;
- import org.orekit.frames.Transform;
- import org.orekit.orbits.Orbit;
- import org.orekit.time.AbsoluteDate;
- import org.orekit.time.TimeInterpolable;
- import org.orekit.time.TimeShiftable;
- import org.orekit.time.TimeStamped;
- import org.orekit.utils.AbsolutePVCoordinates;
- import org.orekit.utils.TimeStampedAngularCoordinates;
- import org.orekit.utils.TimeStampedPVCoordinates;
- /** This class is the representation of a complete state holding orbit, attitude
- * and mass information at a given date.
- *
- * <p>It contains an {@link Orbit orbital state} at a current
- * {@link AbsoluteDate} both handled by an {@link Orbit}, plus the current
- * mass and attitude. Orbit and state are guaranteed to be consistent in terms
- * of date and reference frame. The spacecraft state may also contain additional
- * states, which are simply named double arrays which can hold any user-defined
- * data.
- * </p>
- * <p>
- * The state can be slightly shifted to close dates. This shift is based on
- * a simple Keplerian model for orbit, a linear extrapolation for attitude
- * taking the spin rate into account and no mass change. It is <em>not</em>
- * intended as a replacement for proper orbit and attitude propagation but
- * should be sufficient for either small time shifts or coarse accuracy.
- * </p>
- * <p>
- * The instance <code>SpacecraftState</code> is guaranteed to be immutable.
- * </p>
- * @see org.orekit.propagation.numerical.NumericalPropagator
- * @author Fabien Maussion
- * @author Véronique Pommier-Maurussane
- * @author Luc Maisonobe
- */
- public class SpacecraftState
- implements TimeStamped, TimeShiftable<SpacecraftState>, TimeInterpolable<SpacecraftState>, Serializable {
- /** Serializable UID. */
- private static final long serialVersionUID = 20130407L;
- /** Default mass. */
- private static final double DEFAULT_MASS = 1000.0;
- /**
- * tolerance on date comparison in {@link #checkConsistency(Orbit, Attitude)}. 100 ns
- * corresponds to sub-mm accuracy at LEO orbital velocities.
- */
- private static final double DATE_INCONSISTENCY_THRESHOLD = 100e-9;
- /** Orbital state. */
- private final Orbit orbit;
- /** Trajectory state, when it is not an orbit. */
- private final AbsolutePVCoordinates absPva;
- /** Attitude. */
- private final Attitude attitude;
- /** Current mass (kg). */
- private final double mass;
- /** Additional states. */
- private final Map<String, double[]> additional;
- /** Build a spacecraft state from orbit only.
- * <p>Attitude and mass are set to unspecified non-null arbitrary values.</p>
- * @param orbit the orbit
- */
- public SpacecraftState(final Orbit orbit) {
- this(orbit,
- new LofOffset(orbit.getFrame(), LOFType.VVLH).getAttitude(orbit, orbit.getDate(), orbit.getFrame()),
- DEFAULT_MASS, null);
- }
- /** Build a spacecraft state from orbit and attitude provider.
- * <p>Mass is set to an unspecified non-null arbitrary value.</p>
- * @param orbit the orbit
- * @param attitude attitude
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final Orbit orbit, final Attitude attitude)
- throws IllegalArgumentException {
- this(orbit, attitude, DEFAULT_MASS, null);
- }
- /** Create a new instance from orbit and mass.
- * <p>Attitude law is set to an unspecified default attitude.</p>
- * @param orbit the orbit
- * @param mass the mass (kg)
- */
- public SpacecraftState(final Orbit orbit, final double mass) {
- this(orbit,
- new LofOffset(orbit.getFrame(), LOFType.VVLH).getAttitude(orbit, orbit.getDate(), orbit.getFrame()),
- mass, null);
- }
- /** Build a spacecraft state from orbit, attitude provider and mass.
- * @param orbit the orbit
- * @param attitude attitude
- * @param mass the mass (kg)
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final Orbit orbit, final Attitude attitude, final double mass)
- throws IllegalArgumentException {
- this(orbit, attitude, mass, null);
- }
- /** Build a spacecraft state from orbit only.
- * <p>Attitude and mass are set to unspecified non-null arbitrary values.</p>
- * @param orbit the orbit
- * @param additional additional states
- */
- public SpacecraftState(final Orbit orbit, final Map<String, double[]> additional) {
- this(orbit,
- new LofOffset(orbit.getFrame(), LOFType.VVLH).getAttitude(orbit, orbit.getDate(), orbit.getFrame()),
- DEFAULT_MASS, additional);
- }
- /** Build a spacecraft state from orbit and attitude provider.
- * <p>Mass is set to an unspecified non-null arbitrary value.</p>
- * @param orbit the orbit
- * @param attitude attitude
- * @param additional additional states
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final Orbit orbit, final Attitude attitude, final Map<String, double[]> additional)
- throws IllegalArgumentException {
- this(orbit, attitude, DEFAULT_MASS, additional);
- }
- /** Create a new instance from orbit and mass.
- * <p>Attitude law is set to an unspecified default attitude.</p>
- * @param orbit the orbit
- * @param mass the mass (kg)
- * @param additional additional states
- */
- public SpacecraftState(final Orbit orbit, final double mass, final Map<String, double[]> additional) {
- this(orbit,
- new LofOffset(orbit.getFrame(), LOFType.VVLH).getAttitude(orbit, orbit.getDate(), orbit.getFrame()),
- mass, additional);
- }
- /** Build a spacecraft state from orbit, attitude provider and mass.
- * @param orbit the orbit
- * @param attitude attitude
- * @param mass the mass (kg)
- * @param additional additional states (may be null if no additional states are available)
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final Orbit orbit, final Attitude attitude,
- final double mass, final Map<String, double[]> additional)
- throws IllegalArgumentException {
- checkConsistency(orbit, attitude);
- this.orbit = orbit;
- this.absPva = null;
- this.attitude = attitude;
- this.mass = mass;
- if (additional == null) {
- this.additional = Collections.emptyMap();
- } else {
- this.additional = new HashMap<String, double[]>(additional.size());
- for (final Map.Entry<String, double[]> entry : additional.entrySet()) {
- this.additional.put(entry.getKey(), entry.getValue().clone());
- }
- }
- }
- /** Build a spacecraft state from orbit only.
- * <p>Attitude and mass are set to unspecified non-null arbitrary values.</p>
- * @param absPva position-velocity-acceleration
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva) {
- this(absPva,
- new LofOffset(absPva.getFrame(), LOFType.VVLH).getAttitude(absPva, absPva.getDate(), absPva.getFrame()),
- DEFAULT_MASS, null);
- }
- /** Build a spacecraft state from orbit and attitude provider.
- * <p>Mass is set to an unspecified non-null arbitrary value.</p>
- * @param absPva position-velocity-acceleration
- * @param attitude attitude
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final Attitude attitude)
- throws IllegalArgumentException {
- this(absPva, attitude, DEFAULT_MASS, null);
- }
- /** Create a new instance from orbit and mass.
- * <p>Attitude law is set to an unspecified default attitude.</p>
- * @param absPva position-velocity-acceleration
- * @param mass the mass (kg)
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final double mass) {
- this(absPva,
- new LofOffset(absPva.getFrame(), LOFType.VVLH).getAttitude(absPva, absPva.getDate(), absPva.getFrame()),
- mass, null);
- }
- /** Build a spacecraft state from orbit, attitude provider and mass.
- * @param absPva position-velocity-acceleration
- * @param attitude attitude
- * @param mass the mass (kg)
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final Attitude attitude, final double mass)
- throws IllegalArgumentException {
- this(absPva, attitude, mass, null);
- }
- /** Build a spacecraft state from orbit only.
- * <p>Attitude and mass are set to unspecified non-null arbitrary values.</p>
- * @param absPva position-velocity-acceleration
- * @param additional additional states
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final Map<String, double[]> additional) {
- this(absPva,
- new LofOffset(absPva.getFrame(), LOFType.VVLH).getAttitude(absPva, absPva.getDate(), absPva.getFrame()),
- DEFAULT_MASS, additional);
- }
- /** Build a spacecraft state from orbit and attitude provider.
- * <p>Mass is set to an unspecified non-null arbitrary value.</p>
- * @param absPva position-velocity-acceleration
- * @param attitude attitude
- * @param additional additional states
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final Attitude attitude, final Map<String, double[]> additional)
- throws IllegalArgumentException {
- this(absPva, attitude, DEFAULT_MASS, additional);
- }
- /** Create a new instance from orbit and mass.
- * <p>Attitude law is set to an unspecified default attitude.</p>
- * @param absPva position-velocity-acceleration
- * @param mass the mass (kg)
- * @param additional additional states
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final double mass, final Map<String, double[]> additional) {
- this(absPva,
- new LofOffset(absPva.getFrame(), LOFType.VVLH).getAttitude(absPva, absPva.getDate(), absPva.getFrame()),
- mass, additional);
- }
- /** Build a spacecraft state from orbit, attitude provider and mass.
- * @param absPva position-velocity-acceleration
- * @param attitude attitude
- * @param mass the mass (kg)
- * @param additional additional states (may be null if no additional states are available)
- * @exception IllegalArgumentException if orbit and attitude dates
- * or frames are not equal
- */
- public SpacecraftState(final AbsolutePVCoordinates absPva, final Attitude attitude,
- final double mass, final Map<String, double[]> additional)
- throws IllegalArgumentException {
- checkConsistency(absPva, attitude);
- this.orbit = null;
- this.absPva = absPva;
- this.attitude = attitude;
- this.mass = mass;
- if (additional == null) {
- this.additional = Collections.emptyMap();
- } else {
- this.additional = new HashMap<String, double[]>(additional.size());
- for (final Map.Entry<String, double[]> entry : additional.entrySet()) {
- this.additional.put(entry.getKey(), entry.getValue().clone());
- }
- }
- }
- /** Add an additional state.
- * <p>
- * {@link SpacecraftState SpacecraftState} instances are immutable,
- * so this method does <em>not</em> change the instance, but rather
- * creates a new instance, which has the same orbit, attitude, mass
- * and additional states as the original instance, except it also
- * has the specified state. If the original instance already had an
- * additional state with the same name, it will be overridden. If it
- * did not have any additional state with that name, the new instance
- * will have one more additional state than the original instance.
- * </p>
- * @param name name of the additional state
- * @param value value of the additional state
- * @return a new instance, with the additional state added
- * @see #hasAdditionalState(String)
- * @see #getAdditionalState(String)
- * @see #getAdditionalStates()
- */
- public SpacecraftState addAdditionalState(final String name, final double... value) {
- final Map<String, double[]> newMap = new HashMap<String, double[]>(additional.size() + 1);
- newMap.putAll(additional);
- newMap.put(name, value.clone());
- if (absPva == null) {
- return new SpacecraftState(orbit, attitude, mass, newMap);
- } else {
- return new SpacecraftState(absPva, attitude, mass, newMap);
- }
- }
- /** Check orbit and attitude dates are equal.
- * @param orbit the orbit
- * @param attitude attitude
- * @exception IllegalArgumentException if orbit and attitude dates
- * are not equal
- */
- private static void checkConsistency(final Orbit orbit, final Attitude attitude)
- throws IllegalArgumentException {
- if (FastMath.abs(orbit.getDate().durationFrom(attitude.getDate())) >
- DATE_INCONSISTENCY_THRESHOLD) {
- throw new OrekitIllegalArgumentException(OrekitMessages.ORBIT_AND_ATTITUDE_DATES_MISMATCH,
- orbit.getDate(), attitude.getDate());
- }
- if (orbit.getFrame() != attitude.getReferenceFrame()) {
- throw new OrekitIllegalArgumentException(OrekitMessages.FRAMES_MISMATCH,
- orbit.getFrame().getName(),
- attitude.getReferenceFrame().getName());
- }
- }
- /** Check if the state contains an orbit part.
- * <p>
- * A state contains either an {@link AbsolutePVCoordinates absolute
- * position-velocity-acceleration} or an {@link Orbit orbit}.
- * </p>
- * @return true if state contains an orbit (in which case {@link #getOrbit()}
- * will not throw an exception), or false if the state contains an
- * absolut position-velocity-acceleration (in which case {@link #getAbsPVA()}
- * will not throw an exception)
- */
- public boolean isOrbitDefined() {
- return orbit != null;
- }
- /** Check AbsolutePVCoordinates and attitude dates are equal.
- * @param absPva position-velocity-acceleration
- * @param attitude attitude
- * @exception IllegalArgumentException if orbit and attitude dates
- * are not equal
- */
- private static void checkConsistency(final AbsolutePVCoordinates absPva, final Attitude attitude)
- throws IllegalArgumentException {
- if (FastMath.abs(absPva.getDate().durationFrom(attitude.getDate())) >
- DATE_INCONSISTENCY_THRESHOLD) {
- throw new OrekitIllegalArgumentException(OrekitMessages.ORBIT_AND_ATTITUDE_DATES_MISMATCH,
- absPva.getDate(), attitude.getDate());
- }
- if (absPva.getFrame() != attitude.getReferenceFrame()) {
- throw new OrekitIllegalArgumentException(OrekitMessages.FRAMES_MISMATCH,
- absPva.getFrame().getName(),
- attitude.getReferenceFrame().getName());
- }
- }
- /** Get a time-shifted state.
- * <p>
- * The state can be slightly shifted to close dates. This shift is based on
- * simple models. For orbits, the model is a Keplerian one if no derivatives
- * are available in the orbit, or Keplerian plus quadratic effect of the
- * non-Keplerian acceleration if derivatives are available. For attitude,
- * a polynomial model is used. Neither mass nor additional states change.
- * Shifting is <em>not</em> intended as a replacement for proper orbit
- * and attitude propagation but should be sufficient for small time shifts
- * or coarse accuracy.
- * </p>
- * <p>
- * As a rough order of magnitude, the following table shows the extrapolation
- * errors obtained between this simple shift method and an {@link
- * org.orekit.propagation.numerical.NumericalPropagator numerical
- * propagator} for a low Earth Sun Synchronous Orbit, with a 20x20 gravity field,
- * Sun and Moon third bodies attractions, drag and solar radiation pressure.
- * Beware that these results will be different for other orbits.
- * </p>
- * <table border="1">
- * <caption>Extrapolation Error</caption>
- * <tr style="background-color: #ccccff"><th>interpolation time (s)</th>
- * <th>position error without derivatives (m)</th><th>position error with derivatives (m)</th></tr>
- * <tr><td style="background-color: #eeeeff; padding:5px"> 60</td><td> 18</td><td> 1.1</td></tr>
- * <tr><td style="background-color: #eeeeff; padding:5px">120</td><td> 72</td><td> 9.1</td></tr>
- * <tr><td style="background-color: #eeeeff; padding:5px">300</td><td> 447</td><td> 140</td></tr>
- * <tr><td style="background-color: #eeeeff; padding:5px">600</td><td>1601</td><td>1067</td></tr>
- * <tr><td style="background-color: #eeeeff; padding:5px">900</td><td>3141</td><td>3307</td></tr>
- * </table>
- * @param dt time shift in seconds
- * @return a new state, shifted with respect to the instance (which is immutable)
- * except for the mass and additional states which stay unchanged
- */
- public SpacecraftState shiftedBy(final double dt) {
- if (absPva == null) {
- return new SpacecraftState(orbit.shiftedBy(dt), attitude.shiftedBy(dt),
- mass, additional);
- } else {
- return new SpacecraftState(absPva.shiftedBy(dt), attitude.shiftedBy(dt),
- mass, additional);
- }
- }
- /** {@inheritDoc}
- * <p>
- * The additional states that are interpolated are the ones already present
- * in the instance. The sample instances must therefore have at least the same
- * additional states has the instance. They may have more additional states,
- * but the extra ones will be ignored.
- * </p>
- * <p>
- * The instance and all the sample instances <em>must</em> be based on similar
- * trajectory data, i.e. they must either all be based on orbits or all be based
- * on absolute position-velocity-acceleration. Any inconsistency will trigger
- * an {@link OrekitIllegalStateException}.
- * </p>
- * <p>
- * As this implementation of interpolation is polynomial, it should be used only
- * with small samples (about 10-20 points) in order to avoid <a
- * href="http://en.wikipedia.org/wiki/Runge%27s_phenomenon">Runge's phenomenon</a>
- * and numerical problems (including NaN appearing).
- * </p>
- * @exception OrekitIllegalStateException if some instances are not based on
- * similar trajectory data
- */
- public SpacecraftState interpolate(final AbsoluteDate date,
- final Stream<SpacecraftState> sample) {
- // prepare interpolators
- final List<Orbit> orbits;
- final List<AbsolutePVCoordinates> absPvas;
- if (isOrbitDefined()) {
- orbits = new ArrayList<Orbit>();
- absPvas = null;
- } else {
- orbits = null;
- absPvas = new ArrayList<AbsolutePVCoordinates>();
- }
- final List<Attitude> attitudes = new ArrayList<Attitude>();
- final HermiteInterpolator massInterpolator = new HermiteInterpolator();
- final Map<String, HermiteInterpolator> additionalInterpolators =
- new HashMap<String, HermiteInterpolator>(additional.size());
- for (final String name : additional.keySet()) {
- additionalInterpolators.put(name, new HermiteInterpolator());
- }
- // extract sample data
- sample.forEach(state -> {
- final double deltaT = state.getDate().durationFrom(date);
- if (isOrbitDefined()) {
- orbits.add(state.getOrbit());
- } else {
- absPvas.add(state.getAbsPVA());
- }
- attitudes.add(state.getAttitude());
- massInterpolator.addSamplePoint(deltaT,
- new double[] {
- state.getMass()
- });
- for (final Map.Entry<String, HermiteInterpolator> entry : additionalInterpolators.entrySet()) {
- entry.getValue().addSamplePoint(deltaT, state.getAdditionalState(entry.getKey()));
- }
- });
- // perform interpolations
- final Orbit interpolatedOrbit;
- final AbsolutePVCoordinates interpolatedAbsPva;
- if (isOrbitDefined()) {
- interpolatedOrbit = orbit.interpolate(date, orbits);
- interpolatedAbsPva = null;
- } else {
- interpolatedOrbit = null;
- interpolatedAbsPva = absPva.interpolate(date, absPvas);
- }
- final Attitude interpolatedAttitude = attitude.interpolate(date, attitudes);
- final double interpolatedMass = massInterpolator.value(0)[0];
- final Map<String, double[]> interpolatedAdditional;
- if (additional.isEmpty()) {
- interpolatedAdditional = null;
- } else {
- interpolatedAdditional = new HashMap<String, double[]>(additional.size());
- for (final Map.Entry<String, HermiteInterpolator> entry : additionalInterpolators.entrySet()) {
- interpolatedAdditional.put(entry.getKey(), entry.getValue().value(0));
- }
- }
- // create the complete interpolated state
- if (isOrbitDefined()) {
- return new SpacecraftState(interpolatedOrbit, interpolatedAttitude,
- interpolatedMass, interpolatedAdditional);
- } else {
- return new SpacecraftState(interpolatedAbsPva, interpolatedAttitude,
- interpolatedMass, interpolatedAdditional);
- }
- }
- /** Get the absolute position-velocity-acceleration.
- * <p>
- * A state contains either an {@link AbsolutePVCoordinates absolute
- * position-velocity-acceleration} or an {@link Orbit orbit}. Which
- * one is present can be checked using {@link #isOrbitDefined()}.
- * </p>
- * @return absolute position-velocity-acceleration
- * @exception OrekitIllegalStateException if position-velocity-acceleration is null,
- * which mean the state rather contains an {@link Orbit}
- * @see #isOrbitDefined()
- * @see #getOrbit()
- */
- public AbsolutePVCoordinates getAbsPVA() throws OrekitIllegalStateException {
- if (absPva == null) {
- throw new OrekitIllegalStateException(OrekitMessages.UNDEFINED_ABSOLUTE_PVCOORDINATES);
- }
- return absPva;
- }
- /** Get the current orbit.
- * <p>
- * A state contains either an {@link AbsolutePVCoordinates absolute
- * position-velocity-acceleration} or an {@link Orbit orbit}. Which
- * one is present can be checked using {@link #isOrbitDefined()}.
- * </p>
- * @return the orbit
- * @exception OrekitIllegalStateException if orbit is null,
- * which means the state rather contains an {@link AbsolutePVCoordinates absolute
- * position-velocity-acceleration}
- * @see #isOrbitDefined()
- * @see #getAbsPVA()
- */
- public Orbit getOrbit() throws OrekitIllegalStateException {
- if (orbit == null) {
- throw new OrekitIllegalStateException(OrekitMessages.UNDEFINED_ORBIT);
- }
- return orbit;
- }
- /** Get the date.
- * @return date
- */
- public AbsoluteDate getDate() {
- return (absPva == null) ? orbit.getDate() : absPva.getDate();
- }
- /** Get the defining frame.
- * @return the frame in which state is defined
- */
- public Frame getFrame() {
- return (absPva == null) ? orbit.getFrame() : absPva.getFrame();
- }
- /** Check if an additional state is available.
- * @param name name of the additional state
- * @return true if the additional state is available
- * @see #addAdditionalState(String, double[])
- * @see #getAdditionalState(String)
- * @see #getAdditionalStates()
- */
- public boolean hasAdditionalState(final String name) {
- return additional.containsKey(name);
- }
- /** Check if two instances have the same set of additional states available.
- * <p>
- * Only the names and dimensions of the additional states are compared,
- * not their values.
- * </p>
- * @param state state to compare to instance
- * @exception MathIllegalStateException if an additional state does not have
- * the same dimension in both states
- */
- public void ensureCompatibleAdditionalStates(final SpacecraftState state)
- throws MathIllegalStateException {
- // check instance additional states is a subset of the other one
- for (final Map.Entry<String, double[]> entry : additional.entrySet()) {
- final double[] other = state.additional.get(entry.getKey());
- if (other == null) {
- throw new OrekitException(OrekitMessages.UNKNOWN_ADDITIONAL_STATE,
- entry.getKey());
- }
- if (other.length != entry.getValue().length) {
- throw new MathIllegalStateException(LocalizedCoreFormats.DIMENSIONS_MISMATCH,
- other.length, entry.getValue().length);
- }
- }
- if (state.additional.size() > additional.size()) {
- // the other state has more additional states
- for (final String name : state.additional.keySet()) {
- if (!additional.containsKey(name)) {
- throw new OrekitException(OrekitMessages.UNKNOWN_ADDITIONAL_STATE,
- name);
- }
- }
- }
- }
- /** Get an additional state.
- * @param name name of the additional state
- * @return value of the additional state
- * @see #addAdditionalState(String, double[])
- * @see #hasAdditionalState(String)
- * @see #getAdditionalStates()
- */
- public double[] getAdditionalState(final String name) {
- if (!additional.containsKey(name)) {
- throw new OrekitException(OrekitMessages.UNKNOWN_ADDITIONAL_STATE, name);
- }
- return additional.get(name).clone();
- }
- /** Get an unmodifiable map of additional states.
- * @return unmodifiable map of additional states
- * @see #addAdditionalState(String, double[])
- * @see #hasAdditionalState(String)
- * @see #getAdditionalState(String)
- */
- public Map<String, double[]> getAdditionalStates() {
- return Collections.unmodifiableMap(additional);
- }
- /** Compute the transform from state defining frame to spacecraft frame.
- * <p>The spacecraft frame origin is at the point defined by the orbit
- * (or absolute position-velocity-acceleration), and its orientation is
- * defined by the attitude.</p>
- * @return transform from specified frame to current spacecraft frame
- */
- public Transform toTransform() {
- final TimeStampedPVCoordinates pv = getPVCoordinates();
- return new Transform(pv.getDate(),
- new Transform(pv.getDate(), pv.negate()),
- new Transform(pv.getDate(), attitude.getOrientation()));
- }
- /** Get the central attraction coefficient.
- * @return mu central attraction coefficient (m^3/s^2), or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather than an orbit
- */
- public double getMu() {
- return (absPva == null) ? orbit.getMu() : Double.NaN;
- }
- /** Get the Keplerian period.
- * <p>The Keplerian period is computed directly from semi major axis
- * and central acceleration constant.</p>
- * @return keplerian period in seconds, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- */
- public double getKeplerianPeriod() {
- return (absPva == null) ? orbit.getKeplerianPeriod() : Double.NaN;
- }
- /** Get the Keplerian mean motion.
- * <p>The Keplerian mean motion is computed directly from semi major axis
- * and central acceleration constant.</p>
- * @return keplerian mean motion in radians per second, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- */
- public double getKeplerianMeanMotion() {
- return (absPva == null) ? orbit.getKeplerianMeanMotion() : Double.NaN;
- }
- /** Get the semi-major axis.
- * @return semi-major axis (m), or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- */
- public double getA() {
- return (absPva == null) ? orbit.getA() : Double.NaN;
- }
- /** Get the first component of the eccentricity vector (as per equinoctial parameters).
- * @return e cos(ω + Ω), first component of eccentricity vector, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getE()
- */
- public double getEquinoctialEx() {
- return (absPva == null) ? orbit.getEquinoctialEx() : Double.NaN;
- }
- /** Get the second component of the eccentricity vector (as per equinoctial parameters).
- * @return e sin(ω + Ω), second component of the eccentricity vector, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getE()
- */
- public double getEquinoctialEy() {
- return (absPva == null) ? orbit.getEquinoctialEy() : Double.NaN;
- }
- /** Get the first component of the inclination vector (as per equinoctial parameters).
- * @return tan(i/2) cos(Ω), first component of the inclination vector, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getI()
- */
- public double getHx() {
- return (absPva == null) ? orbit.getHx() : Double.NaN;
- }
- /** Get the second component of the inclination vector (as per equinoctial parameters).
- * @return tan(i/2) sin(Ω), second component of the inclination vector, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getI()
- */
- public double getHy() {
- return (absPva == null) ? orbit.getHy() : Double.NaN;
- }
- /** Get the true latitude argument (as per equinoctial parameters).
- * @return v + ω + Ω true longitude argument (rad), or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getLE()
- * @see #getLM()
- */
- public double getLv() {
- return (absPva == null) ? orbit.getLv() : Double.NaN;
- }
- /** Get the eccentric latitude argument (as per equinoctial parameters).
- * @return E + ω + Ω eccentric longitude argument (rad), or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getLv()
- * @see #getLM()
- */
- public double getLE() {
- return (absPva == null) ? orbit.getLE() : Double.NaN;
- }
- /** Get the mean longitude argument (as per equinoctial parameters).
- * @return M + ω + Ω mean latitude argument (rad), or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getLv()
- * @see #getLE()
- */
- public double getLM() {
- return (absPva == null) ? orbit.getLM() : Double.NaN;
- }
- // Additional orbital elements
- /** Get the eccentricity.
- * @return eccentricity, or {code Double.NaN} if the
- * state is contains an absolute position-velocity-acceleration rather
- * than an orbit
- * @see #getEquinoctialEx()
- * @see #getEquinoctialEy()
- */
- public double getE() {
- return (absPva == null) ? orbit.getE() : Double.NaN;
- }
- /** Get the inclination.
- * @return inclination (rad)
- * @see #getHx()
- * @see #getHy()
- */
- public double getI() {
- return (absPva == null) ? orbit.getI() : Double.NaN;
- }
- /** Get the {@link TimeStampedPVCoordinates} in orbit definition frame.
- * <p>
- * Compute the position and velocity of the satellite. This method caches its
- * results, and recompute them only when the method is called with a new value
- * for mu. The result is provided as a reference to the internally cached
- * {@link TimeStampedPVCoordinates}, so the caller is responsible to copy it in a separate
- * {@link TimeStampedPVCoordinates} if it needs to keep the value for a while.
- * </p>
- * @return pvCoordinates in orbit definition frame
- */
- public TimeStampedPVCoordinates getPVCoordinates() {
- return (absPva == null) ? orbit.getPVCoordinates() : absPva.getPVCoordinates();
- }
- /** Get the {@link TimeStampedPVCoordinates} in given output frame.
- * <p>
- * Compute the position and velocity of the satellite. This method caches its
- * results, and recompute them only when the method is called with a new value
- * for mu. The result is provided as a reference to the internally cached
- * {@link TimeStampedPVCoordinates}, so the caller is responsible to copy it in a separate
- * {@link TimeStampedPVCoordinates} if it needs to keep the value for a while.
- * </p>
- * @param outputFrame frame in which coordinates should be defined
- * @return pvCoordinates in orbit definition frame
- */
- public TimeStampedPVCoordinates getPVCoordinates(final Frame outputFrame) {
- return (absPva == null) ? orbit.getPVCoordinates(outputFrame) : absPva.getPVCoordinates(outputFrame);
- }
- /** Get the attitude.
- * @return the attitude.
- */
- public Attitude getAttitude() {
- return attitude;
- }
- /** Gets the current mass.
- * @return the mass (kg)
- */
- public double getMass() {
- return mass;
- }
- /** Replace the instance with a data transfer object for serialization.
- * @return data transfer object that will be serialized
- */
- private Object writeReplace() {
- return isOrbitDefined() ? new DTOO(this) : new DTOA(this);
- }
- /** Internal class used only for serialization. */
- private static class DTOO implements Serializable {
- /** Serializable UID. */
- private static final long serialVersionUID = 20150916L;
- /** Orbit. */
- private final Orbit orbit;
- /** Attitude and mass double values. */
- private double[] d;
- /** Additional states. */
- private final Map<String, double[]> additional;
- /** Simple constructor.
- * @param state instance to serialize
- */
- private DTOO(final SpacecraftState state) {
- this.orbit = state.orbit;
- this.additional = state.additional.isEmpty() ? null : state.additional;
- final Rotation rotation = state.attitude.getRotation();
- final Vector3D spin = state.attitude.getSpin();
- final Vector3D rotationAcceleration = state.attitude.getRotationAcceleration();
- this.d = new double[] {
- rotation.getQ0(), rotation.getQ1(), rotation.getQ2(), rotation.getQ3(),
- spin.getX(), spin.getY(), spin.getZ(),
- rotationAcceleration.getX(), rotationAcceleration.getY(), rotationAcceleration.getZ(),
- state.mass
- };
- }
- /** Replace the de-serialized data transfer object with a {@link SpacecraftState}.
- * @return replacement {@link SpacecraftState}
- */
- private Object readResolve() {
- return new SpacecraftState(orbit,
- new Attitude(orbit.getFrame(),
- new TimeStampedAngularCoordinates(orbit.getDate(),
- new Rotation(d[0], d[1], d[2], d[3], false),
- new Vector3D(d[4], d[5], d[6]),
- new Vector3D(d[7], d[8], d[9]))),
- d[10], additional);
- }
- }
- /** Internal class used only for serialization. */
- private static class DTOA implements Serializable {
- /** Serializable UID. */
- private static final long serialVersionUID = 20150916L;
- /** Absolute position-velocity-acceleration. */
- private final AbsolutePVCoordinates absPva;
- /** Attitude and mass double values. */
- private double[] d;
- /** Additional states. */
- private final Map<String, double[]> additional;
- /** Simple constructor.
- * @param state instance to serialize
- */
- private DTOA(final SpacecraftState state) {
- this.absPva = state.absPva;
- this.additional = state.additional.isEmpty() ? null : state.additional;
- final Rotation rotation = state.attitude.getRotation();
- final Vector3D spin = state.attitude.getSpin();
- final Vector3D rotationAcceleration = state.attitude.getRotationAcceleration();
- this.d = new double[] {
- rotation.getQ0(), rotation.getQ1(), rotation.getQ2(), rotation.getQ3(),
- spin.getX(), spin.getY(), spin.getZ(),
- rotationAcceleration.getX(), rotationAcceleration.getY(), rotationAcceleration.getZ(),
- state.mass
- };
- }
- /** Replace the deserialized data transfer object with a {@link SpacecraftState}.
- * @return replacement {@link SpacecraftState}
- */
- private Object readResolve() {
- return new SpacecraftState(absPva,
- new Attitude(absPva.getFrame(),
- new TimeStampedAngularCoordinates(absPva.getDate(),
- new Rotation(d[0], d[1], d[2], d[3], false),
- new Vector3D(d[4], d[5], d[6]),
- new Vector3D(d[7], d[8], d[9]))),
- d[10], additional);
- }
- }
- @Override
- public String toString() {
- return "SpacecraftState{" +
- "orbit=" + orbit +
- ", attitude=" + attitude +
- ", mass=" + mass +
- ", additional=" + additional +
- '}';
- }
- }