LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator.java
/*
* Copyright (C) 2020 Alberto Irurueta Carro (alberto@irurueta.com)
*
* Licensed 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 com.irurueta.navigation.inertial.calibration.magnetometer;
import com.irurueta.algebra.Matrix;
import com.irurueta.navigation.LockedException;
import com.irurueta.navigation.NotReadyException;
import com.irurueta.navigation.frames.ECEFPosition;
import com.irurueta.navigation.frames.NEDPosition;
import com.irurueta.navigation.inertial.calibration.CalibrationException;
import com.irurueta.navigation.inertial.calibration.StandardDeviationBodyMagneticFluxDensity;
import com.irurueta.navigation.inertial.wmm.WorldMagneticModel;
import com.irurueta.numerical.robust.LMedSRobustEstimator;
import com.irurueta.numerical.robust.LMedSRobustEstimatorListener;
import com.irurueta.numerical.robust.RobustEstimator;
import com.irurueta.numerical.robust.RobustEstimatorException;
import com.irurueta.numerical.robust.RobustEstimatorMethod;
import java.io.IOException;
import java.util.List;
/**
* Robustly estimates magnetometer soft-iron cross couplings and
* scaling factors using LMedS algorithm.
* <p>
* To use this calibrator at least 7 measurements taken at a single known
* position and instant must be taken at 7 different unknown orientations and
* zero velocity when common z-axis is assumed, otherwise at least 10
* measurements are required.
* <p>
* Measured magnetic flux density is assumed to follow the model shown below:
* <pre>
* mBmeas = bm + (I + Mm) * mBtrue + w
* </pre>
* Where:
* - mBmeas is the measured magnetic flux density. This is a 3x1 vector.
* - bm is magnetometer hard-iron bias. Ideally, on a perfect magnetometer,
* this should be a 3x1 zero vector.
* - I is the 3x3 identity matrix.
* - Mm is the 3x3 soft-iron matrix containing cross-couplings and scaling
* factors. Ideally, on a perfect magnetometer, this should be a 3x3 zero
* matrix.
* - mBtrue is ground-truth magnetic flux density. This is a 3x1 vector.
* - w is measurement noise. This is a 3x1 vector.
* Notice that this calibrator assumes that all measurements are taken in
* a short span of time, where Earth magnetic field can be assumed to be
* constant at provided location and instant.
*/
public class LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator extends
RobustKnownHardIronPositionAndInstantMagnetometerCalibrator {
/**
* Default value to be used for stop threshold. Stop threshold can be used to
* avoid keeping the algorithm unnecessarily iterating in case that best
* estimated threshold using median of residuals is not small enough. Once a
* solution is found that generates a threshold below this value, the
* algorithm will stop.
* The stop threshold can be used to prevent the LMedS algorithm iterating
* too many times in cases where samples have a very similar accuracy.
* For instance, in cases where proportion of outliers is very small (close
* to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would
* iterate for a long time trying to find the best solution when indeed
* there is no need to do that if a reasonable threshold has already been
* reached.
* Because of this behaviour the stop threshold can be set to a value much
* lower than the one typically used in LMedS, and yet the algorithm could
* still produce even smaller thresholds in estimated results.
*/
public static final double DEFAULT_STOP_THRESHOLD = 1e-9;
/**
* Minimum allowed stop threshold value.
*/
public static final double MIN_STOP_THRESHOLD = 0.0;
/**
* Threshold to be used to keep the algorithm iterating in case that best
* estimated threshold using median of residuals is not small enough. Once
* a solution is found that generates a threshold below this value, the
* algorithm will stop.
* The stop threshold can be used to prevent the LMedS algorithm iterating
* too many times in cases where samples have a very similar accuracy.
* For instance, in cases where proportion of outliers is very small (close
* to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would
* iterate for a long time trying to find the best solution when indeed
* there is no need to do that if a reasonable threshold has already been
* reached.
* Because of this behaviour the stop threshold can be set to a value much
* lower than the one typically used in LMedS, and yet the algorithm could
* still produce even smaller thresholds in estimated results.
*/
private double stopThreshold = DEFAULT_STOP_THRESHOLD;
/**
* Constructor.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator() {
super();
}
/**
* Constructor.
*
* @param listener listener to handle events raised by this calibrator.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(listener);
}
/**
* Constructor.
*
* @param measurements list of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final List<StandardDeviationBodyMagneticFluxDensity> measurements) {
super(measurements);
}
/**
* Constructor.
*
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final boolean commonAxisUsed) {
super(commonAxisUsed);
}
/**
* Constructor.
*
* @param magneticModel Earth's magnetic model. If null, a default model
* will be used instead.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final WorldMagneticModel magneticModel) {
super(magneticModel);
}
/**
* Constructor.
*
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final double[] hardIron) {
super(hardIron);
}
/**
* Constructor.
*
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final Matrix hardIron) {
super(hardIron);
}
/**
* Constructor.
*
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final Matrix hardIron, final Matrix initialMm) {
super(hardIron, initialMm);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final NEDPosition position) {
super(position);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements) {
super(position, measurements);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param listener listener to handle events raised by this calibrator.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed) {
super(position, measurements, commonAxisUsed);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param listener listener to handle events raised by this calibrator.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final double[] hardIron) {
super(position, measurements, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final double[] hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final double[] hardIron) {
super(position, measurements, commonAxisUsed, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final double[] hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron) {
super(position, measurements, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron) {
super(position, measurements, commonAxisUsed, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final Matrix initialMm) {
super(position, measurements, hardIron, initialMm);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final Matrix initialMm,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, initialMm, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron, final Matrix initialMm) {
super(position, measurements, commonAxisUsed, hardIron, initialMm);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final NEDPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron, final Matrix initialMm,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, initialMm, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(final ECEFPosition position) {
super(position);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements) {
super(position, measurements);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param listener listener to handle events raised by this calibrator.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed) {
super(position, measurements, commonAxisUsed);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param listener listener to handle events raised by this calibrator.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final double[] hardIron) {
super(position, measurements, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final double[] hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final double[] hardIron) {
super(position, measurements, commonAxisUsed, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron array does
* not have length 3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final double[] hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron) {
super(position, measurements, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron) {
super(position, measurements, commonAxisUsed, hardIron);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final Matrix initialMm) {
super(position, measurements, hardIron, initialMm);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final Matrix hardIron, final Matrix initialMm,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, hardIron, initialMm, listener);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron, final Matrix initialMm) {
super(position, measurements, commonAxisUsed, hardIron, initialMm);
}
/**
* Constructor.
*
* @param position position where body magnetic flux density measurements
* have been taken.
* @param measurements collection of body magnetic flux density
* measurements with standard deviation of
* magnetometer measurements taken at the same
* position with zero velocity and unknown different
* orientations.
* @param commonAxisUsed indicates whether z-axis is assumed to be common
* for the accelerometer, gyroscope and magnetometer.
* @param hardIron known hard-iron.
* @param initialMm initial soft-iron matrix containing scale factors
* and cross coupling errors.
* @param listener listener to handle events raised by this calibrator.
* @throws IllegalArgumentException if provided hard-iron matrix is not
* 3x1 or if soft-iron matrix is not
* 3x3.
*/
public LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator(
final ECEFPosition position, final List<StandardDeviationBodyMagneticFluxDensity> measurements,
final boolean commonAxisUsed, final Matrix hardIron, final Matrix initialMm,
final RobustKnownHardIronPositionAndInstantMagnetometerCalibratorListener listener) {
super(position, measurements, commonAxisUsed, hardIron, initialMm, listener);
}
/**
* Returns threshold to be used to keep the algorithm iterating in case that
* best estimated threshold using median of residuals is not small enough.
* Once a solution is found that generates a threshold below this value, the
* algorithm will stop.
* The stop threshold can be used to prevent the LMedS algorithm to iterate
* too many times in cases where samples have a very similar accuracy.
* For instance, in cases where proportion of outliers is very small (close
* to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would
* iterate for a long time trying to find the best solution when indeed
* there is no need to do that if a reasonable threshold has already been
* reached.
* Because of this behaviour the stop threshold can be set to a value much
* lower than the one typically used in RANSAC, and yet the algorithm could
* still produce even smaller thresholds in estimated results.
*
* @return stop threshold to stop the algorithm prematurely when a certain
* accuracy has been reached.
*/
public double getStopThreshold() {
return stopThreshold;
}
/**
* Sets threshold to be used to keep the algorithm iterating in case that
* best estimated threshold using median of residuals is not small enough.
* Once a solution is found that generates a threshold below this value,
* the algorithm will stop.
* The stop threshold can be used to prevent the LMedS algorithm to iterate
* too many times in cases where samples have a very similar accuracy.
* For instance, in cases where proportion of outliers is very small (close
* to 0%), and samples are very accurate (i.e. 1e-6), the algorithm would
* iterate for a long time trying to find the best solution when indeed
* there is no need to do that if a reasonable threshold has already been
* reached.
* Because of this behaviour the stop threshold can be set to a value much
* lower than the one typically used in RANSAC, and yet the algorithm could
* still produce even smaller thresholds in estimated results.
*
* @param stopThreshold stop threshold to stop the algorithm prematurely
* when a certain accuracy has been reached.
* @throws IllegalArgumentException if provided value is zero or negative.
* @throws LockedException if calibrator is currently running.
*/
public void setStopThreshold(final double stopThreshold) throws LockedException {
if (running) {
throw new LockedException();
}
if (stopThreshold <= MIN_STOP_THRESHOLD) {
throw new IllegalArgumentException();
}
this.stopThreshold = stopThreshold;
}
/**
* Estimates magnetometer calibration parameters containing soft-iron
* scale factors and cross-coupling errors.
*
* @throws LockedException if calibrator is currently running.
* @throws NotReadyException if calibrator is not ready.
* @throws CalibrationException if estimation fails for numerical reasons.
*/
@SuppressWarnings("DuplicatedCode")
@Override
public void calibrate() throws LockedException, NotReadyException, CalibrationException {
if (running) {
throw new LockedException();
}
if (!isReady()) {
throw new NotReadyException();
}
final var innerEstimator = new LMedSRobustEstimator<>(new LMedSRobustEstimatorListener<Matrix>() {
@Override
public int getTotalSamples() {
return measurements.size();
}
@Override
public int getSubsetSize() {
return preliminarySubsetSize;
}
@Override
public void estimatePreliminarSolutions(final int[] samplesIndices, final List<Matrix> solutions) {
computePreliminarySolutions(samplesIndices, solutions);
}
@Override
public double computeResidual(final Matrix currentEstimation, final int i) {
return computeError(measurements.get(i), currentEstimation);
}
@Override
public boolean isReady() {
return LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator.this.isReady();
}
@Override
public void onEstimateStart(final RobustEstimator<Matrix> estimator) {
// no action needed
}
@Override
public void onEstimateEnd(final RobustEstimator<Matrix> estimator) {
// no action needed
}
@Override
public void onEstimateNextIteration(final RobustEstimator<Matrix> estimator, final int iteration) {
if (listener != null) {
listener.onCalibrateNextIteration(
LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator.this,
iteration);
}
}
@Override
public void onEstimateProgressChange(final RobustEstimator<Matrix> estimator, final float progress) {
if (listener != null) {
listener.onCalibrateProgressChange(
LMedSRobustKnownHardIronPositionAndInstantMagnetometerCalibrator.this,
progress);
}
}
});
try {
running = true;
if (listener != null) {
listener.onCalibrateStart(this);
}
inliersData = null;
initialize();
innerEstimator.setConfidence(confidence);
innerEstimator.setMaxIterations(maxIterations);
innerEstimator.setProgressDelta(progressDelta);
innerEstimator.setStopThreshold(stopThreshold);
final var preliminaryResult = innerEstimator.estimate();
inliersData = innerEstimator.getInliersData();
attemptRefine(preliminaryResult);
if (listener != null) {
listener.onCalibrateEnd(this);
}
} catch (final com.irurueta.numerical.LockedException e) {
throw new LockedException(e);
} catch (final com.irurueta.numerical.NotReadyException e) {
throw new NotReadyException(e);
} catch (final RobustEstimatorException | IOException e) {
throw new CalibrationException(e);
} finally {
running = false;
}
}
/**
* Returns method being used for robust estimation.
*
* @return method being used for robust estimation.
*/
@Override
public RobustEstimatorMethod getMethod() {
return RobustEstimatorMethod.LMEDS;
}
/**
* Indicates whether this calibrator requires quality scores for each
* measurement or not.
*
* @return true if quality scores are required, false otherwise.
*/
@Override
public boolean isQualityScoresRequired() {
return false;
}
}