GroundRefining.java

/* Copyright 2013-2017 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 RefiningPleiades;

import java.io.File;
import java.util.List;
import java.util.Locale;

import org.hipparchus.geometry.euclidean.threed.Vector3D;
import org.hipparchus.util.FastMath;
import org.orekit.bodies.BodyShape;
import org.orekit.bodies.GeodeticPoint;
import org.orekit.data.DataProvidersManager;
import org.orekit.data.DirectoryCrawler;
import org.orekit.errors.OrekitException;
import org.orekit.forces.gravity.potential.NormalizedSphericalHarmonicsProvider;
import org.orekit.orbits.Orbit;
import org.orekit.rugged.api.AlgorithmId;
import org.orekit.rugged.api.BodyRotatingFrameId;
import org.orekit.rugged.api.EllipsoidId;
import org.orekit.rugged.api.InertialFrameId;
import org.orekit.rugged.api.Rugged;
import org.orekit.rugged.api.RuggedBuilder;
import org.orekit.rugged.errors.RuggedException;
import org.orekit.rugged.linesensor.LineSensor;
import org.orekit.rugged.refining.generators.GroundMeasureGenerator;
import org.orekit.rugged.refining.measures.Noise;
import org.orekit.rugged.refining.measures.SensorToGroundMapping;
import org.orekit.rugged.refining.metrics.DistanceTools;
import org.orekit.rugged.refining.models.OrbitModel;
import org.orekit.rugged.refining.models.PleiadesViewingModel;
import org.orekit.time.AbsoluteDate;
import org.orekit.utils.AngularDerivativesFilter;
import org.orekit.utils.CartesianDerivativesFilter;
import org.orekit.utils.PVCoordinates;
import org.orekit.utils.TimeStampedAngularCoordinates;
import org.orekit.utils.TimeStampedPVCoordinates;

/**
 * Class for testing refining (fulcrum points study)
 * with or without noisy measurements
 * @author Jonathan Guinet
 * @author Lucie Labat-Allee
 * @author Guylaine Prat
 * @see SensorToGroundMapping
 * @see GroundMeasureGenerator
 * @since 2.0
 */
public class GroundRefining extends Refining {

    /** Pleiades viewing model */
    PleiadesViewingModel pleiadesViewingModel;

    /** Orbit model */
    OrbitModel orbitmodel;

    /** Sensor name */
    String sensorName;

    /** Rugged instance */
    Rugged rugged;

    /** Ground measurements */
    GroundMeasureGenerator measures;

    /** Main function
     */
    public static void main(String[] args) {
    	
    	try {
    		
            // Initialize Orekit, assuming an orekit-data folder is in user home directory
            // ---------------------------------------------------------------------------
            File home       = new File(System.getProperty("user.home"));
            File orekitData = new File(home, "COTS/orekit-data");
            DataProvidersManager.getInstance().addProvider(new DirectoryCrawler(orekitData));

            // Initialize refining context
            // ---------------------------
            GroundRefining refining = new GroundRefining();

            // Sensor's definition: create Pleiades viewing model
            // --------------------------------------------------
            System.out.format("**** Build Pleiades viewing model and orbit definition **** %n");
            PleiadesViewingModel pleiadesViewingModel = refining.getPleiadesViewingModel();
            AbsoluteDate minDate =  pleiadesViewingModel.getMinDate();
            AbsoluteDate maxDate =  pleiadesViewingModel.getMaxDate();
            AbsoluteDate refDate = pleiadesViewingModel.getDatationReference();
            LineSensor lineSensor =  pleiadesViewingModel.getLineSensor();

            // Satellite position, velocity and attitude: create an orbit model
            // ----------------------------------------------------------------
            OrbitModel orbitmodel = refining.getOrbitmodel();
            BodyShape earth = orbitmodel.createEarth();
            NormalizedSphericalHarmonicsProvider gravityField = orbitmodel.createGravityField();
            Orbit orbit = orbitmodel.createOrbit(gravityField.getMu(), refDate);

            // Nadir's pointing
            final double [] rollPoly = {0.0,0.0,0.0};
            double[] pitchPoly = {0.0,0.0};
            double[] yawPoly = {0.0,0.0,0.0};
            orbitmodel.setLOFTransform(rollPoly, pitchPoly, yawPoly, minDate);

            // Satellite attitude
            List<TimeStampedAngularCoordinates> satelliteQList = 
            		orbitmodel.orbitToQ(orbit, earth, minDate.shiftedBy(-0.0), maxDate.shiftedBy(+0.0), 0.25);
            int nbQPoints = 2;

            // Position and velocities
            PVCoordinates PV = orbit.getPVCoordinates(earth.getBodyFrame());
            List<TimeStampedPVCoordinates> satellitePVList = 
            		orbitmodel.orbitToPV(orbit, earth, minDate.shiftedBy(-0.0), maxDate.shiftedBy(+0.0), 0.25);
            int nbPVPoints = 8;

            // Convert frame and coordinates type in one call
            GeodeticPoint gp = earth.transform(PV.getPosition(), earth.getBodyFrame(), orbit.getDate());

            System.out.format(Locale.US, "Geodetic Point at date %s : φ = %8.10f °, λ = %8.10f %n",
                              orbit.getDate().toString(),
                              FastMath.toDegrees(gp.getLatitude()),
                              FastMath.toDegrees(gp.getLongitude()));

            // Rugged initialization
            // ---------------------
            System.out.format("\n**** Rugged initialization **** %n");
            RuggedBuilder ruggedBuilder = new RuggedBuilder();

            ruggedBuilder.addLineSensor(lineSensor);
            ruggedBuilder.setAlgorithm(AlgorithmId.IGNORE_DEM_USE_ELLIPSOID);
            ruggedBuilder.setEllipsoid(EllipsoidId.WGS84, BodyRotatingFrameId.ITRF);
            ruggedBuilder.setTimeSpan(minDate,maxDate, 0.001, 5.0);
            ruggedBuilder.setTrajectory(InertialFrameId.EME2000, satellitePVList,nbPVPoints, 
            		                    CartesianDerivativesFilter.USE_PV, satelliteQList,
            		                    nbQPoints, AngularDerivativesFilter.USE_R);
            
            ruggedBuilder.setName("Rugged_refining");

            refining.setRugged(ruggedBuilder.build());

            // Compute ground sample distance (GSD)
            // ------------------------------------
            double [] gsd = refining.computeGSD(lineSensor);
            System.out.format("GSD - X: %2.2f Y: %2.2f **** %n", gsd[0], gsd[1]);

            // Initialize disruptions:
            // -----------------------
            // Introduce rotations around instrument axes (roll and pitch translations, scale factor)
            System.out.format("\n**** Add disruptions: roll and pitch rotations, scale factor **** %n");
            double rollValue =  FastMath.toRadians(-0.01);
            double pitchValue = FastMath.toRadians(0.02);
            double factorValue = 1.05;
            System.out.format("roll: %3.5f \tpitch: %3.5f \tfactor: %3.5f \n",rollValue, pitchValue, factorValue);

            // Apply disruptions on physical model
            refining.applyDisruptions(refining.getRugged(), refining.getSensorName(),
                                      rollValue, pitchValue, factorValue);

            // Generate measures (observations) from physical model disrupted
            // --------------------------------------------------------------
            int lineSampling = 1000;
            int pixelSampling = 1000;

            // Noise definition
            final Noise noise = new Noise(0,3); /* distribution: gaussian(0), vector dimension:3 */
            final double[] mean = {0.0,0.0,0.0};                /* {lat mean, long mean, alt mean} */
            final double[] standardDeviation = {0.0,0.0,0.0};   /* {lat std, long std, alt std} */
            noise.setMean(mean);
            noise.setStandardDeviation(standardDeviation);

            GroundMeasureGenerator measures = refining.generateNoisyPoints(lineSampling, pixelSampling,
                                                                           refining.getRugged(), refining.getSensorName(),
                                                                           refining.getPleiadesViewingModel().getDimension(),
                                                                           noise);
            refining.setMeasures(measures);

            // Compute ground truth residues
            // -----------------------------
            System.out.format("\n**** Ground truth residuals **** %n");
            refining.computeMetrics(measures.getGroundMapping(), refining.getRugged(), false);

            // Initialize physical model without disruptions
            // ---------------------------------------------
            System.out.format("\n**** Initialize physical model without disruptions: reset Roll/Pitch/Factor **** %n");
            refining.resetModel(refining.getRugged(), refining.getSensorName(), true);

            // Compute initial residues
            // ------------------------
            System.out.format("\n**** Initial Residuals  **** %n");
            refining.computeMetrics(measures.getGroundMapping(), refining.getRugged(), false);

            // Start optimization
            // ------------------
            System.out.format("\n**** Start optimization  **** %n");

            int maxIterations = 100;
            double convergenceThreshold =  1e-14;

            refining.optimization(maxIterations, convergenceThreshold, measures.getObservables(), refining.getRugged());

            // Check estimated values
            // ----------------------
            System.out.format("\n**** Check parameters ajustement **** %n");
            refining.paramsEstimation(refining.getRugged(), refining.getSensorName(),
                                      rollValue, pitchValue, factorValue);

            // Compute statistics
            // ------------------
            System.out.format("\n**** Compute Statistics **** %n");

            // Residues computed in meters
            refining.computeMetrics(measures.getGroundMapping(), refining.getRugged(), false);

            // Residues computed in degrees
            refining.computeMetrics(measures.getGroundMapping(), refining.getRugged(), true);

        } catch (OrekitException oe) {
            System.err.println(oe.getLocalizedMessage());
            System.exit(1);
        } catch (RuggedException re) {
            System.err.println(re.getLocalizedMessage());
            System.exit(1);
        }
    }

    /** Constructor */
    public GroundRefining() throws RuggedException, OrekitException {

        sensorName = "line";
        pleiadesViewingModel = new PleiadesViewingModel(sensorName);
        orbitmodel =  new OrbitModel();
    }

     /** Estimate ground sample distance (GSD)
     * @param LineSensor line sensor
     * @return the GSD
     */
    private double[] computeGSD(final LineSensor lineSensor) throws RuggedException {

        // Get position
        Vector3D position = lineSensor.getPosition(); // This returns a zero vector since we set the relative position of the sensor w.r.T the satellite to 0.

        // Get upper left geodetic point
        AbsoluteDate firstLineDate = lineSensor.getDate(0);
        Vector3D los = lineSensor.getLOS(firstLineDate,0);
        GeodeticPoint upLeftPoint = rugged.directLocation(firstLineDate, position, los);
        los = lineSensor.getLOS(firstLineDate,pleiadesViewingModel.dimension-1);

        // Get center geodetic point
        AbsoluteDate lineDate = lineSensor.getDate(pleiadesViewingModel.dimension/2);
        los = lineSensor.getLOS(lineDate,pleiadesViewingModel.dimension/2);

        // Get upper right geodetic point
        int pixelPosition = pleiadesViewingModel.dimension-1;
        los = lineSensor.getLOS(firstLineDate,pixelPosition);
        GeodeticPoint upperRight = rugged.directLocation(firstLineDate, position, los);

        // Get lower left geodetic point
        AbsoluteDate lineDate_y = lineSensor.getDate(pleiadesViewingModel.dimension-1);
        los = lineSensor.getLOS(lineDate_y,0);
        GeodeticPoint lowerLeft = rugged.directLocation(lineDate_y, position, los);

        double gsdX = DistanceTools.computeDistanceInMeter(upLeftPoint.getLongitude(), upLeftPoint.getLatitude(),
        		                    upperRight.getLongitude() , upperRight.getLatitude())/pleiadesViewingModel.dimension;
        double gsdY = DistanceTools.computeDistanceInMeter(upLeftPoint.getLongitude(), upLeftPoint.getLatitude(),
        		                    lowerLeft.getLongitude() , lowerLeft.getLatitude())/pleiadesViewingModel.dimension;

        double [] gsd = {gsdX, gsdY};
        return gsd;
    }
    
    /**
     * Get the Pleiades viewing model
     * @return the Pleiades viewing model
     */
    public PleiadesViewingModel getPleiadesViewingModel() {
        return pleiadesViewingModel;
    }

    /**
     * Set the Pleiades viewing model
     * @param pleiadesViewingModel Pleiades viewing model to set
     */
    public void setPleiadesViewingModel(PleiadesViewingModel pleiadesViewingModel) {
        this.pleiadesViewingModel = pleiadesViewingModel;
    }

    /**
     * Get the orbit model
     * @return the orbit model
     */
    public OrbitModel getOrbitmodel() {
        return orbitmodel;
    }

    /**
     * Set the orbit model
     * @param orbitmodel the orbit model to set
     */
    public void setOrbitmodel(OrbitModel orbitmodel) {
        this.orbitmodel = orbitmodel;
    }

    /**
     * Get the sensor name
     * @return the sensor name
     */
    public String getSensorName() {
        return sensorName;
    }

    /**
     * Get the Rugged instance
     * @return the rugged instance
     */
    public Rugged getRugged() {
        return rugged;
    }

    /**
     * Set the Rugged instance
     * @param rugged the Rugged instance to set
     */
    public void setRugged(Rugged rugged) {
        this.rugged = rugged;
    }

    /**
     * Set the measures
     * @param measures the measures to set
     */
    public void setMeasures(GroundMeasureGenerator measures) {
        this.measures = measures;
    }
}