Package com.irurueta.navigation.inertial.calibration.magnetometer

Class RobustKnownHardIronAndFrameMagnetometerCalibrator

java.lang.Object

com.irurueta.navigation.inertial.calibration.magnetometer.RobustKnownHardIronAndFrameMagnetometerCalibrator

All Implemented Interfaces:

KnownHardIronMagnetometerCalibrator, MagnetometerCalibrator, MagnetometerNonLinearCalibrator, OrderedStandardDeviationFrameBodyMagneticFluxDensityMagnetometerCalibrator, QualityScoredMagnetometerCalibrator

Direct Known Subclasses:

LMedSRobustKnownHardIronAndFrameMagnetometerCalibrator, MSACRobustKnownHardIronAndFrameMagnetometerCalibrator, PROMedSRobustKnownHardIronAndFrameMagnetometerCalibrator, PROSACRobustKnownHardIronAndFrameMagnetometerCalibrator, RANSACRobustKnownHardIronAndFrameMagnetometerCalibrator

public abstract class RobustKnownHardIronAndFrameMagnetometerCalibrator
extends Object
implements MagnetometerNonLinearCalibrator, KnownHardIronMagnetometerCalibrator, OrderedStandardDeviationFrameBodyMagneticFluxDensityMagnetometerCalibrator, QualityScoredMagnetometerCalibrator

This is an abstract class to robustly estimate magnetometer soft-iron cross couplings and scaling factors.

To use this calibrator at least 3 measurements at different known frames must be provided. In other words, magnetometer samples must be obtained at 3 different positions or orientations. Notice that frame velocities are ignored by this calibrator.

Measured magnetic flux density is assumed to follow the model shown below:

     mBmeas = bm + (I + Mm) * mBtrue + w
 

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.

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	commonAxisUsed	This flag indicates whether z-axis is assumed to be common for accelerometer, gyroscope and magnetometer.
protected double	confidence	Amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%).
static final double	DEFAULT_CONFIDENCE	Constant defining default confidence of the estimated result, which is 99%.
static final boolean	DEFAULT_KEEP_COVARIANCE	Indicates that covariance is kept by default after refining result.
static final int	DEFAULT_MAX_ITERATIONS	Default maximum allowed number of iterations.
static final float	DEFAULT_PROGRESS_DELTA	Default amount of progress variation before notifying a change in estimation progress.
static final boolean	DEFAULT_REFINE_PRELIMINARY_SOLUTIONS	Indicates that by default preliminary solutions are refined.
static final boolean	DEFAULT_REFINE_RESULT	Indicates that result is refined by default using a non-linear calibrator (which uses a Levenberg-Marquardt fitter).
static final com.irurueta.numerical.robust.RobustEstimatorMethod	DEFAULT_ROBUST_METHOD	Default robust estimator method when none is provided.
static final boolean	DEFAULT_USE_COMMON_Z_AXIS	Indicates whether by default a common z-axis is assumed for the accelerometer, gyroscope and magnetometer.
static final boolean	DEFAULT_USE_LINEAR_CALIBRATOR	Indicates that by default a linear calibrator is used for preliminary solution estimation.
private double	estimatedChiSq	Estimated chi square value.
private int	estimatedChiSqDegreesOfFreedom	Estimated degrees of freedom of chi square value.
private com.irurueta.algebra.Matrix	estimatedCovariance	Estimated covariance matrix for estimated parameters.
private com.irurueta.algebra.Matrix	estimatedMm	Estimated magnetometer soft-iron matrix containing scale factors and cross coupling errors.
private double	estimatedMse	Estimated mean square error respect to provided measurements.
private double	estimatedP	Estimated probability of finding a smaller chi square value expressed as a value between 0.0 and 1.0.
private double	estimatedQ	Estimated measure of quality of estimated fit as a value between 0.0 and 1.0.
private double	estimatedReducedChiSq	Estimated reduced chi square value.
private double	hardIronX	X-coordinate of known hard-iron bias.
private double	hardIronY	Y-coordinate of known hard-iron bias.
private double	hardIronZ	Z-coordinate of known hard-iron bias.
private double	initialMxy	Initial x-y cross coupling error.
private double	initialMxz	Initial x-z cross coupling error.
private double	initialMyx	Initial y-x cross coupling error.
private double	initialMyz	Initial y-z cross coupling error.
private double	initialMzx	Initial z-x cross coupling error.
private double	initialMzy	Initial z-y cross coupling error.
private double	initialSx	Initial x scaling factor.
private double	initialSy	Initial y scaling factor.
private double	initialSz	Initial z scaling factor.
protected com.irurueta.numerical.robust.InliersData	inliersData	Data related to inlier found after calibration.
private boolean	keepCovariance	Indicates whether covariance must be kept after refining result.
private final KnownHardIronAndFrameMagnetometerLinearLeastSquaresCalibrator	linearCalibrator	A linear least squares calibrator.
protected RobustKnownHardIronAndFrameMagnetometerCalibratorListener	listener	Listener to be notified of events such as when calibration starts, ends or its progress significantly changes.
private WorldMagneticModel	magneticModel	Contains Earth's magnetic model.
static final double	MAX_CONFIDENCE	Maximum allowed confidence value.
static final float	MAX_PROGRESS_DELTA	Maximum allowed value for progress delta.
protected int	maxIterations	Maximum allowed number of iterations.
protected List<StandardDeviationFrameBodyMagneticFluxDensity>	measurements	Contains a list of body magnetic flux density measurements taken at different frames (positions and orientations) and containing the standard deviation of magnetometer measurements.
static final double	MIN_CONFIDENCE	Minimum allowed confidence value.
static final int	MIN_ITERATIONS	Minimum allowed number of iterations.
static final float	MIN_PROGRESS_DELTA	Minimum allowed value for progress delta.
static final int	MINIMUM_MEASUREMENTS	Required minimum number of measurements.
private final KnownHardIronAndFrameMagnetometerNonLinearLeastSquaresCalibrator	nonLinearCalibrator	A non-linear least squares calibrator.
protected int	preliminarySubsetSize	Size of subsets to be checked during robust estimation.
protected float	progressDelta	Amount of progress variation before notifying a progress change during calibration.
private boolean	refinePreliminarySolutions	Indicates whether preliminary solutions must be refined after an initial linear solution is found.
protected boolean	refineResult	Indicates whether result must be refined using a non linear calibrator over found inliers.
protected boolean	running	Indicates whether estimator is running.
private boolean	useLinearCalibrator	Indicates whether a linear calibrator is used or not for preliminary solutions.
private WMMEarthMagneticFluxDensityEstimator	wmmEstimator	World Magnetic Model estimator.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator()	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(boolean commonAxisUsed)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Constructor.
protected	RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected void	attemptRefine(com.irurueta.algebra.Matrix preliminaryResult)	Attempts to refine calibration parameters if refinement is requested.
protected double	computeError(StandardDeviationFrameBodyMagneticFluxDensity measurement, com.irurueta.algebra.Matrix preliminaryResult)	Computes error of a preliminary result respect a given measurement.
protected void	computePreliminarySolutions(int[] samplesIndices, List<com.irurueta.algebra.Matrix> solutions)	Computes a preliminary solution for a subset of samples picked by a robust estimator.
private static double	convertMagneticFluxDensity(double value, com.irurueta.units.MagneticFluxDensityUnit unit)	Converts magnetic flux density value and unit to Teslas.
private static double	convertMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity magneticFluxDensity)	Converts magnetic flux density instance to Teslas.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create()	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(boolean commonAxisUsed)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(boolean commonAxisUsed, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, boolean commonAxisUsed, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Creates a robust known frame magnetometer calibrator using default robust method.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
static RobustKnownHardIronAndFrameMagnetometerCalibrator	create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, com.irurueta.numerical.robust.RobustEstimatorMethod method)	Creates a robust known frame magnetometer calibrator.
double	getConfidence()	Returns amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%).
double	getEstimatedChiSq()	Gets estimated chi square value.
int	getEstimatedChiSqDegreesOfFreedom()	Gets estimated chi square degrees of freedom.
com.irurueta.algebra.Matrix	getEstimatedCovariance()	Gets estimated covariance matrix for estimated calibration parameters.
com.irurueta.algebra.Matrix	getEstimatedMm()	Gets estimated magnetometer soft-iron matrix containing scale factors and cross coupling errors.
double	getEstimatedMse()	Gets estimated mean square error respect to provided measurements.
Double	getEstimatedMxy()	Gets estimated x-y cross-coupling error.
Double	getEstimatedMxz()	Gets estimated x-z cross-coupling error.
Double	getEstimatedMyx()	Gets estimated y-x cross-coupling error.
Double	getEstimatedMyz()	Gets estimated y-z cross-coupling error.
Double	getEstimatedMzx()	Gets estimated z-x cross-coupling error.
Double	getEstimatedMzy()	Gets estimated z-y cross-coupling error.
double	getEstimatedP()	Gets estimated probability of finding a smaller chi square value expressed as a value between 0.0 and 1.0.
double	getEstimatedQ()	Gets estimated measure of quality of estimated fit as a value between 0.0 and 1.0.
double	getEstimatedReducedChiSq()	Gets estimated reduced chi square value.
Double	getEstimatedSx()	Gets estimated x-axis scale factor.
Double	getEstimatedSy()	Gets estimated y-axis scale factor.
Double	getEstimatedSz()	Gets estimated z-axis scale factor.
double[]	getHardIron()	Gets known hard-iron bias as an array.
void	getHardIron(double[] result)	Gets known hard-iron bias as an array.
MagneticFluxDensityTriad	getHardIronAsTriad()	Gets known hard-iron.
void	getHardIronAsTriad(MagneticFluxDensityTriad result)	Gets known hard-iron.
com.irurueta.algebra.Matrix	getHardIronMatrix()	Gets known hard-iron bias as a column matrix.
void	getHardIronMatrix(com.irurueta.algebra.Matrix result)	Gets known hard-iron bias as a column matrix.
double	getHardIronX()	Gets x-coordinate of known magnetometer hard-iron bias.
com.irurueta.units.MagneticFluxDensity	getHardIronXAsMagneticFluxDensity()	Gets known x coordinate of magnetometer hard-iron.
void	getHardIronXAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)	Gets known x coordinate of magnetometer hard-iron.
double	getHardIronY()	Gets y-coordinate of known magnetometer hard-iron bias.
com.irurueta.units.MagneticFluxDensity	getHardIronYAsMagneticFluxDensity()	Gets known y coordinate of magnetometer hard-iron.
void	getHardIronYAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)	Gets known y coordinate of magnetometer hard-iron.
double	getHardIronZ()	Gets z-coordinate of known magnetometer hard-iron bias.
com.irurueta.units.MagneticFluxDensity	getHardIronZAsMagneticFluxDensity()	Gets known z coordinate of magnetometer hard-iron.
void	getHardIronZAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)	Gets known z coordinate of magnetometer hard-iron.
com.irurueta.algebra.Matrix	getInitialMm()	Gets initial scale factors and cross coupling errors matrix.
void	getInitialMm(com.irurueta.algebra.Matrix result)	Gets initial scale factors and cross coupling errors matrix.
double	getInitialMxy()	Gets initial x-y cross coupling error.
double	getInitialMxz()	Gets initial x-z cross coupling error.
double	getInitialMyx()	Gets initial y-x cross coupling error.
double	getInitialMyz()	Gets initial y-z cross coupling error.
double	getInitialMzx()	Gets initial z-x cross coupling error.
double	getInitialMzy()	Gets initial z-y cross coupling error.
double	getInitialSx()	Gets initial x scaling factor.
double	getInitialSy()	Gets initial y scaling factor.
double	getInitialSz()	Gets initial z scaling factor.
com.irurueta.numerical.robust.InliersData	getInliersData()	Gets data related to inliers found after estimation.
RobustKnownHardIronAndFrameMagnetometerCalibratorListener	getListener()	Gets listener to handle events raised by this calibrator.
WorldMagneticModel	getMagneticModel()	Gets Earth's magnetic model.
int	getMaxIterations()	Returns maximum allowed number of iterations.
List<StandardDeviationFrameBodyMagneticFluxDensity>	getMeasurements()	Gets a list of body magnetic flux density measurements taken at different frames (positions, orientations and velocities).
MagnetometerCalibratorMeasurementType	getMeasurementType()	Indicates the type of measurement used by this calibrator.
abstract com.irurueta.numerical.robust.RobustEstimatorMethod	getMethod()	Returns method being used for robust estimation.
int	getMinimumRequiredMeasurements()	Gets minimum number of required measurements.
int	getPreliminarySubsetSize()	Gets size of subsets to be checked during robust estimation.
float	getProgressDelta()	Returns amount of progress variation before notifying a progress change during calibration.
double[]	getQualityScores()	Returns quality scores corresponding to each measurement.
boolean	isCommonAxisUsed()	Indicates whether z-axis is assumed to be common for accelerometer, gyroscope and magnetometer.
boolean	isCovarianceKept()	Indicates whether covariance must be kept after refining result.
boolean	isLinearCalibratorUsed()	Indicates whether a linear calibrator is used or not for preliminary solutions.
boolean	isOrderedMeasurementsRequired()	Indicates whether this calibrator requires ordered measurements in a list or not.
boolean	isPreliminarySolutionRefined()	Indicates whether preliminary solutions must be refined after an initial linear solution is found.
boolean	isReady()	Indicates whether calibrator is ready to start the estimator.
boolean	isResultRefined()	Indicates whether result must be refined using a non-linear solver over found inliers.
boolean	isRunning()	Indicates whether calibrator is currently running or no.
void	setCommonAxisUsed(boolean commonAxisUsed)	Specifies whether z-axis is assumed to be common for accelerometer and gyroscope.
void	setConfidence(double confidence)	Sets amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%).
void	setCovarianceKept(boolean keepCovariance)	Specifies whether covariance must be kept after refining result.
void	setHardIron(double[] hardIron)	Sets known hard-iron bias as an array.
void	setHardIron(com.irurueta.algebra.Matrix hardIron)	Sets known hard-iron bias.
void	setHardIron(MagneticFluxDensityTriad hardIron)	Sets known hard-iron.
void	setHardIronCoordinates(double hardIronX, double hardIronY, double hardIronZ)	Sets known hard-iron bias coordinates of magnetometer expressed in Teslas (T).
void	setHardIronCoordinates(com.irurueta.units.MagneticFluxDensity hardIronX, com.irurueta.units.MagneticFluxDensity hardIronY, com.irurueta.units.MagneticFluxDensity hardIronZ)	Sets known hard-iron coordinates.
void	setHardIronX(double hardIronX)	Sets x-coordinate of known magnetometer hard-iron bias.
void	setHardIronX(com.irurueta.units.MagneticFluxDensity hardIronX)	Sets known x-coordinate of magnetometer hard-iron.
void	setHardIronY(double hardIronY)	Sets y-coordinate of known magnetometer hard-iron bias.
void	setHardIronY(com.irurueta.units.MagneticFluxDensity hardIronY)	Sets known y-coordinate of magnetometer hard-iron.
void	setHardIronZ(double hardIronZ)	Sets z-coordinate of known magnetometer hard-iron bias.
void	setHardIronZ(com.irurueta.units.MagneticFluxDensity hardIronZ)	Sets known z-coordinate of magnetometer hard-iron.
void	setInitialCrossCouplingErrors(double initialMxy, double initialMxz, double initialMyx, double initialMyz, double initialMzx, double initialMzy)	Sets initial cross coupling errors.
void	setInitialMm(com.irurueta.algebra.Matrix initialMm)	Sets initial scale factors and cross coupling errors matrix.
void	setInitialMxy(double initialMxy)	Sets initial x-y cross coupling error.
void	setInitialMxz(double initialMxz)	Sets initial x-z cross coupling error.
void	setInitialMyx(double initialMyx)	Sets initial y-x cross coupling error.
void	setInitialMyz(double initialMyz)	Sets initial y-z cross coupling error.
void	setInitialMzx(double initialMzx)	Sets initial z-x cross coupling error.
void	setInitialMzy(double initialMzy)	Sets initial z-y cross coupling error.
void	setInitialScalingFactors(double initialSx, double initialSy, double initialSz)	Sets initial scaling factors.
void	setInitialScalingFactorsAndCrossCouplingErrors(double initialSx, double initialSy, double initialSz, double initialMxy, double initialMxz, double initialMyx, double initialMyz, double initialMzx, double initialMzy)	Sets initial scaling factors and cross coupling errors.
void	setInitialSx(double initialSx)	Sets initial x scaling factor.
void	setInitialSy(double initialSy)	Sets initial y scaling factor.
void	setInitialSz(double initialSz)	Sets initial z scaling factor.
void	setLinearCalibratorUsed(boolean linearCalibratorUsed)	Specifies whether a linear calibrator is used or not for preliminary solutions.
void	setListener(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)	Sets listener to handle events raised by this calibrator.
void	setMagneticModel(WorldMagneticModel magneticModel)	Sets Earth's magnetic model.
void	setMaxIterations(int maxIterations)	Sets maximum allowed number of iterations.
void	setMeasurements(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)	Sets a list of body magnetic flux density measurements taken at different frames (positions, orientations and velocities).
void	setPreliminarySolutionRefined(boolean preliminarySolutionRefined)	Specifies whether preliminary solutions must be refined after an initial linear solution is found.
void	setPreliminarySubsetSize(int preliminarySubsetSize)	Sets size of subsets to be checked during robust estimation.
void	setProgressDelta(float progressDelta)	Sets amount of progress variation before notifying a progress change during calibration.
void	setQualityScores(double[] qualityScores)	Sets quality scores corresponding to each measurement.
void	setResultRefined(boolean refineResult)	Specifies whether result must be refined using a non-linear solver over found inliers.
protected void	setupWmmEstimator()	Setups World Magnetic Model estimator.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.irurueta.navigation.inertial.calibration.magnetometer.MagnetometerCalibrator

calibrate, isQualityScoresRequired

Field Details

DEFAULT_USE_COMMON_Z_AXIS

public static final boolean DEFAULT_USE_COMMON_Z_AXIS

Indicates whether by default a common z-axis is assumed for the accelerometer, gyroscope and magnetometer.

See Also:

• Constant Field Values

MINIMUM_MEASUREMENTS

public static final int MINIMUM_MEASUREMENTS

Required minimum number of measurements.

See Also:

• Constant Field Values

DEFAULT_USE_LINEAR_CALIBRATOR

public static final boolean DEFAULT_USE_LINEAR_CALIBRATOR

Indicates that by default a linear calibrator is used for preliminary solution estimation. The result obtained on each preliminary solution might be later refined.

See Also:

• Constant Field Values

DEFAULT_REFINE_PRELIMINARY_SOLUTIONS

public static final boolean DEFAULT_REFINE_PRELIMINARY_SOLUTIONS

Indicates that by default preliminary solutions are refined.

See Also:

• Constant Field Values

DEFAULT_ROBUST_METHOD

public static final com.irurueta.numerical.robust.RobustEstimatorMethod DEFAULT_ROBUST_METHOD

Default robust estimator method when none is provided.

DEFAULT_REFINE_RESULT

public static final boolean DEFAULT_REFINE_RESULT

Indicates that result is refined by default using a non-linear calibrator (which uses a Levenberg-Marquardt fitter).

See Also:

• Constant Field Values

DEFAULT_KEEP_COVARIANCE

public static final boolean DEFAULT_KEEP_COVARIANCE

Indicates that covariance is kept by default after refining result.

See Also:

• Constant Field Values

DEFAULT_PROGRESS_DELTA

public static final float DEFAULT_PROGRESS_DELTA

Default amount of progress variation before notifying a change in estimation progress. By default this is set to 5%.

See Also:

• Constant Field Values

MIN_PROGRESS_DELTA

public static final float MIN_PROGRESS_DELTA

Minimum allowed value for progress delta.

See Also:

• Constant Field Values

MAX_PROGRESS_DELTA

public static final float MAX_PROGRESS_DELTA

Maximum allowed value for progress delta.

See Also:

• Constant Field Values

DEFAULT_CONFIDENCE

public static final double DEFAULT_CONFIDENCE

Constant defining default confidence of the estimated result, which is 99%. This means that with a probability of 99% estimation will be accurate because chosen sub-samples will be inliers.

See Also:

• Constant Field Values

DEFAULT_MAX_ITERATIONS

public static final int DEFAULT_MAX_ITERATIONS

Default maximum allowed number of iterations.

See Also:

• Constant Field Values

MIN_CONFIDENCE

public static final double MIN_CONFIDENCE

Minimum allowed confidence value.

See Also:

• Constant Field Values

MAX_CONFIDENCE

public static final double MAX_CONFIDENCE

Maximum allowed confidence value.

See Also:

• Constant Field Values

MIN_ITERATIONS

public static final int MIN_ITERATIONS

Minimum allowed number of iterations.

See Also:

• Constant Field Values

measurements

protected List<StandardDeviationFrameBodyMagneticFluxDensity> measurements

Contains a list of body magnetic flux density measurements taken at different frames (positions and orientations) and containing the standard deviation of magnetometer measurements. If a single device magnetometer needs to be calibrated, typically all measurements are taken at the same position, with zero velocity and multiple orientations. However, if we just want to calibrate a given magnetometer model (e.g. obtain an average and less precise calibration for the magnetometer of a given phone model), we could take measurements collected throughout the planet at multiple positions while the phone remains static (e.g. while charging), hence each measurement position will change, velocity will remain zero and orientation will be typically constant at horizontal orientation while the phone remains on a flat surface.

listener

protected RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener

Listener to be notified of events such as when calibration starts, ends or its progress significantly changes.

running

protected boolean running

Indicates whether estimator is running.

progressDelta

protected float progressDelta

Amount of progress variation before notifying a progress change during calibration.

confidence

protected double confidence

Amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%). The amount of confidence indicates the probability that the estimated result is correct. Usually this value will be close to 1.0, but not exactly 1.0.

maxIterations

protected int maxIterations

Maximum allowed number of iterations. When the maximum number of iterations is exceeded, result will not be available, however an approximate result will be available for retrieval.

inliersData

protected com.irurueta.numerical.robust.InliersData inliersData

Data related to inlier found after calibration.

refineResult

protected boolean refineResult

Indicates whether result must be refined using a non linear calibrator over found inliers. If true, inliers will be computed and kept in any implementation regardless of the settings.

preliminarySubsetSize

protected int preliminarySubsetSize

Size of subsets to be checked during robust estimation.

commonAxisUsed

private boolean commonAxisUsed

This flag indicates whether z-axis is assumed to be common for accelerometer, gyroscope and magnetometer. When enabled, this eliminates 3 variables from soft-iron (Mm) matrix.

hardIronX

private double hardIronX

X-coordinate of known hard-iron bias. This is expressed in Teslas (T).

hardIronY

private double hardIronY

Y-coordinate of known hard-iron bias. This is expressed in Teslas (T).

hardIronZ

private double hardIronZ

Z-coordinate of known hard-iron bias. This is expressed in Teslas (T).

initialSx

private double initialSx

Initial x scaling factor.

initialSy

private double initialSy

Initial y scaling factor.

initialSz

private double initialSz

Initial z scaling factor.

initialMxy

private double initialMxy

Initial x-y cross coupling error.

initialMxz

private double initialMxz

Initial x-z cross coupling error.

initialMyx

private double initialMyx

Initial y-x cross coupling error.

initialMyz

private double initialMyz

Initial y-z cross coupling error.

initialMzx

private double initialMzx

Initial z-x cross coupling error.

initialMzy

private double initialMzy

Initial z-y cross coupling error.

useLinearCalibrator

private boolean useLinearCalibrator

Indicates whether a linear calibrator is used or not for preliminary solutions.

refinePreliminarySolutions

private boolean refinePreliminarySolutions

Indicates whether preliminary solutions must be refined after an initial linear solution is found.

estimatedMm

private com.irurueta.algebra.Matrix estimatedMm

Estimated magnetometer soft-iron matrix containing scale factors and cross coupling errors. This is the product of matrix Tm containing cross coupling errors and Km containing scaling factors. So tat:

     Mm = [sx    mxy  mxz] = Tm*Km
          [myx   sy   myz]
          [mzx   mzy  sz ]
 

Where:

     Km = [sx 0   0 ]
          [0  sy  0 ]
          [0  0   sz]
 

and

     Tm = [1          -alphaXy    alphaXz ]
          [alphaYx    1           -alphaYz]
          [-alphaZx   alphaZy     1       ]
 

Hence:

     Mm = [sx    mxy  mxz] = Tm*Km =  [sx             -sy * alphaXy   sz * alphaXz ]
          [myx   sy   myz]            [sx * alphaYx   sy              -sz * alphaYz]
          [mzx   mzy  sz ]            [-sx * alphaZx  sy * alphaZy    sz           ]
 

This instance allows any 3x3 matrix however, typically alphaYx, alphaZx and alphaZy are considered to be zero if the accelerometer z-axis is assumed to be the same as the body z-axis. When this is assumed, myx = mzx = mzy = 0 and the Mm matrix becomes upper diagonal:

     Mm = [sx    mxy  mxz]
          [0     sy   myz]
          [0     0    sz ]
 

Values of this matrix are unit-less.

keepCovariance

private boolean keepCovariance

Indicates whether covariance must be kept after refining result. This setting is only taken into account if result is refined.

estimatedCovariance

private com.irurueta.algebra.Matrix estimatedCovariance

Estimated covariance matrix for estimated parameters.

estimatedChiSq

private double estimatedChiSq

Estimated chi square value.

estimatedChiSqDegreesOfFreedom

private int estimatedChiSqDegreesOfFreedom

Estimated degrees of freedom of chi square value. Degrees of freedom is equal to the number of sampled data minus the number of estimated parameters.

estimatedReducedChiSq

private double estimatedReducedChiSq

Estimated reduced chi square value. This is equal to estimated chi square value divided by its degrees of freedom. Ideally this value should be close to 1.0.

estimatedMse

private double estimatedMse

Estimated mean square error respect to provided measurements.

estimatedP

private double estimatedP

Estimated probability of finding a smaller chi square value expressed as a value between 0.0 and 1.0. The smaller the found chi square value is, the better the fit of the estimated parameters to the actual parameter. Thus, the smaller the chance of finding a smaller chi square value, then the better the estimated fit is.

estimatedQ

private double estimatedQ

Estimated measure of quality of estimated fit as a value between 0.0 and 1.0. The larger the quality value is, the better the fit that has been estimated.

magneticModel

private WorldMagneticModel magneticModel

Contains Earth's magnetic model.

linearCalibrator

private final KnownHardIronAndFrameMagnetometerLinearLeastSquaresCalibrator linearCalibrator

A linear least squares calibrator.

nonLinearCalibrator

private final KnownHardIronAndFrameMagnetometerNonLinearLeastSquaresCalibrator nonLinearCalibrator

A non-linear least squares calibrator.

wmmEstimator

private WMMEarthMagneticFluxDensityEstimator wmmEstimator

World Magnetic Model estimator.

Constructor Details

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator()

Constructor.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Constructor.

Parameters:

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)

Constructor.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Constructor.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

listener - listener to handle events raised by this calibrator.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(boolean commonAxisUsed)

Constructor.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Constructor.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed)

Constructor.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

RobustKnownHardIronAndFrameMagnetometerCalibrator

protected RobustKnownHardIronAndFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Constructor.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

Method Details

getHardIronX

public double getHardIronX()

Gets x-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

getHardIronX in interface KnownHardIronMagnetometerCalibrator

Returns:

x-coordinate of known magnetometer hard-iron bias.

setHardIronX

public void setHardIronX(double hardIronX)
                  throws com.irurueta.navigation.LockedException

Sets x-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

setHardIronX in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronX - x coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronY

public double getHardIronY()

Gets y-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

getHardIronY in interface KnownHardIronMagnetometerCalibrator

Returns:

y-coordinate of known magnetometer hard-iron bias.

setHardIronY

public void setHardIronY(double hardIronY)
                  throws com.irurueta.navigation.LockedException

Sets y-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

setHardIronY in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronY - y coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronZ

public double getHardIronZ()

Gets z-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

getHardIronZ in interface KnownHardIronMagnetometerCalibrator

Returns:

z-coordinate of known magnetometer hard-iron bias.

setHardIronZ

public void setHardIronZ(double hardIronZ)
                  throws com.irurueta.navigation.LockedException

Sets z-coordinate of known magnetometer hard-iron bias. This is expressed in Teslas (T).

Specified by:

setHardIronZ in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronZ - z coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronXAsMagneticFluxDensity

public com.irurueta.units.MagneticFluxDensity getHardIronXAsMagneticFluxDensity()

Gets known x coordinate of magnetometer hard-iron.

Specified by:

getHardIronXAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Returns:

x coordinate of magnetometer hard-iron.

getHardIronXAsMagneticFluxDensity

public void getHardIronXAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)

Gets known x coordinate of magnetometer hard-iron.

Specified by:

getHardIronXAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result will be stored.

setHardIronX

public void setHardIronX(com.irurueta.units.MagneticFluxDensity hardIronX)
                  throws com.irurueta.navigation.LockedException

Sets known x-coordinate of magnetometer hard-iron.

Specified by:

setHardIronX in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronX - known x-coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronYAsMagneticFluxDensity

public com.irurueta.units.MagneticFluxDensity getHardIronYAsMagneticFluxDensity()

Gets known y coordinate of magnetometer hard-iron.

Specified by:

getHardIronYAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Returns:

y coordinate of magnetometer hard-iron.

getHardIronYAsMagneticFluxDensity

public void getHardIronYAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)

Gets known y coordinate of magnetometer hard-iron.

Specified by:

getHardIronYAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result will be stored.

setHardIronY

public void setHardIronY(com.irurueta.units.MagneticFluxDensity hardIronY)
                  throws com.irurueta.navigation.LockedException

Sets known y-coordinate of magnetometer hard-iron.

Specified by:

setHardIronY in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronY - known y-coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronZAsMagneticFluxDensity

public com.irurueta.units.MagneticFluxDensity getHardIronZAsMagneticFluxDensity()

Gets known z coordinate of magnetometer hard-iron.

Specified by:

getHardIronZAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Returns:

z coordinate of magnetometer hard-iron.

getHardIronZAsMagneticFluxDensity

public void getHardIronZAsMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity result)

Gets known z coordinate of magnetometer hard-iron.

Specified by:

getHardIronZAsMagneticFluxDensity in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result will be stored.

setHardIronZ

public void setHardIronZ(com.irurueta.units.MagneticFluxDensity hardIronZ)
                  throws com.irurueta.navigation.LockedException

Sets known z-coordinate of magnetometer hard-iron.

Specified by:

setHardIronZ in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronZ - known z-coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

setHardIronCoordinates

public void setHardIronCoordinates(double hardIronX,
 double hardIronY,
 double hardIronZ)
                            throws com.irurueta.navigation.LockedException

Sets known hard-iron bias coordinates of magnetometer expressed in Teslas (T).

Specified by:

setHardIronCoordinates in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronX - x-coordinate of magnetometer hard-iron.

hardIronY - y-coordinate of magnetometer hard-iron.

hardIronZ - z-coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

setHardIronCoordinates

public void setHardIronCoordinates(com.irurueta.units.MagneticFluxDensity hardIronX,
 com.irurueta.units.MagneticFluxDensity hardIronY,
 com.irurueta.units.MagneticFluxDensity hardIronZ)
                            throws com.irurueta.navigation.LockedException

Sets known hard-iron coordinates.

Specified by:

setHardIronCoordinates in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIronX - x-coordinate of magnetometer hard-iron.

hardIronY - y-coordinate of magnetometer hard-iron.

hardIronZ - z-coordinate of magnetometer hard-iron.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIronAsTriad

public MagneticFluxDensityTriad getHardIronAsTriad()

Gets known hard-iron.

Specified by:

getHardIronAsTriad in interface KnownHardIronMagnetometerCalibrator

Returns:

known hard-iron.

getHardIronAsTriad

public void getHardIronAsTriad(MagneticFluxDensityTriad result)

Gets known hard-iron.

Specified by:

getHardIronAsTriad in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result will be stored.

setHardIron

public void setHardIron(MagneticFluxDensityTriad hardIron)
                 throws com.irurueta.navigation.LockedException

Sets known hard-iron.

Specified by:

setHardIron in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIron - hard-iron to be set.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialSx

public double getInitialSx()

Gets initial x scaling factor.

Specified by:

getInitialSx in interface MagnetometerNonLinearCalibrator

Returns:

initial x scaling factor.

setInitialSx

public void setInitialSx(double initialSx)
                  throws com.irurueta.navigation.LockedException

Sets initial x scaling factor.

Specified by:

setInitialSx in interface MagnetometerNonLinearCalibrator

Parameters:

initialSx - initial x scaling factor.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialSy

public double getInitialSy()

Gets initial y scaling factor.

Specified by:

getInitialSy in interface MagnetometerNonLinearCalibrator

Returns:

initial y scaling factor.

setInitialSy

public void setInitialSy(double initialSy)
                  throws com.irurueta.navigation.LockedException

Sets initial y scaling factor.

Specified by:

setInitialSy in interface MagnetometerNonLinearCalibrator

Parameters:

initialSy - initial y scaling factor.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialSz

public double getInitialSz()

Gets initial z scaling factor.

Specified by:

getInitialSz in interface MagnetometerNonLinearCalibrator

Returns:

initial z scaling factor.

setInitialSz

public void setInitialSz(double initialSz)
                  throws com.irurueta.navigation.LockedException

Sets initial z scaling factor.

Specified by:

setInitialSz in interface MagnetometerNonLinearCalibrator

Parameters:

initialSz - initial z scaling factor.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMxy

public double getInitialMxy()

Gets initial x-y cross coupling error.

Specified by:

getInitialMxy in interface MagnetometerNonLinearCalibrator

Returns:

initial x-y cross coupling error.

setInitialMxy

public void setInitialMxy(double initialMxy)
                   throws com.irurueta.navigation.LockedException

Sets initial x-y cross coupling error.

Specified by:

setInitialMxy in interface MagnetometerNonLinearCalibrator

Parameters:

initialMxy - initial x-y cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMxz

public double getInitialMxz()

Gets initial x-z cross coupling error.

Specified by:

getInitialMxz in interface MagnetometerNonLinearCalibrator

Returns:

initial x-z cross coupling error.

setInitialMxz

public void setInitialMxz(double initialMxz)
                   throws com.irurueta.navigation.LockedException

Sets initial x-z cross coupling error.

Specified by:

setInitialMxz in interface MagnetometerNonLinearCalibrator

Parameters:

initialMxz - initial x-z cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMyx

public double getInitialMyx()

Gets initial y-x cross coupling error.

Specified by:

getInitialMyx in interface MagnetometerNonLinearCalibrator

Returns:

initial y-x cross coupling error.

setInitialMyx

public void setInitialMyx(double initialMyx)
                   throws com.irurueta.navigation.LockedException

Sets initial y-x cross coupling error.

Specified by:

setInitialMyx in interface MagnetometerNonLinearCalibrator

Parameters:

initialMyx - initial y-x cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMyz

public double getInitialMyz()

Gets initial y-z cross coupling error.

Specified by:

getInitialMyz in interface MagnetometerNonLinearCalibrator

Returns:

initial y-z cross coupling error.

setInitialMyz

public void setInitialMyz(double initialMyz)
                   throws com.irurueta.navigation.LockedException

Sets initial y-z cross coupling error.

Specified by:

setInitialMyz in interface MagnetometerNonLinearCalibrator

Parameters:

initialMyz - initial y-z cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMzx

public double getInitialMzx()

Gets initial z-x cross coupling error.

Specified by:

getInitialMzx in interface MagnetometerNonLinearCalibrator

Returns:

initial z-x cross coupling error.

setInitialMzx

public void setInitialMzx(double initialMzx)
                   throws com.irurueta.navigation.LockedException

Sets initial z-x cross coupling error.

Specified by:

setInitialMzx in interface MagnetometerNonLinearCalibrator

Parameters:

initialMzx - initial z-x cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInitialMzy

public double getInitialMzy()

Gets initial z-y cross coupling error.

Specified by:

getInitialMzy in interface MagnetometerNonLinearCalibrator

Returns:

initial z-y cross coupling error.

setInitialMzy

public void setInitialMzy(double initialMzy)
                   throws com.irurueta.navigation.LockedException

Sets initial z-y cross coupling error.

Specified by:

setInitialMzy in interface MagnetometerNonLinearCalibrator

Parameters:

initialMzy - initial z-y cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

setInitialScalingFactors

public void setInitialScalingFactors(double initialSx,
 double initialSy,
 double initialSz)
                              throws com.irurueta.navigation.LockedException

Sets initial scaling factors.

Specified by:

setInitialScalingFactors in interface MagnetometerNonLinearCalibrator

Parameters:

initialSx - initial x scaling factor.

initialSy - initial y scaling factor.

initialSz - initial z scaling factor.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

setInitialCrossCouplingErrors

public void setInitialCrossCouplingErrors(double initialMxy,
 double initialMxz,
 double initialMyx,
 double initialMyz,
 double initialMzx,
 double initialMzy)
                                   throws com.irurueta.navigation.LockedException

Sets initial cross coupling errors.

Specified by:

setInitialCrossCouplingErrors in interface MagnetometerNonLinearCalibrator

Parameters:

initialMxy - initial x-y cross coupling error.

initialMxz - initial x-z cross coupling error.

initialMyx - initial y-x cross coupling error.

initialMyz - initial y-z cross coupling error.

initialMzx - initial z-x cross coupling error.

initialMzy - initial z-y cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

setInitialScalingFactorsAndCrossCouplingErrors

public void setInitialScalingFactorsAndCrossCouplingErrors(double initialSx,
 double initialSy,
 double initialSz,
 double initialMxy,
 double initialMxz,
 double initialMyx,
 double initialMyz,
 double initialMzx,
 double initialMzy)
                                                    throws com.irurueta.navigation.LockedException

Sets initial scaling factors and cross coupling errors.

Specified by:

setInitialScalingFactorsAndCrossCouplingErrors in interface MagnetometerNonLinearCalibrator

Parameters:

initialSx - initial x scaling factor.

initialSy - initial y scaling factor.

initialSz - initial z scaling factor.

initialMxy - initial x-y cross coupling error.

initialMxz - initial x-z cross coupling error.

initialMyx - initial y-x cross coupling error.

initialMyz - initial y-z cross coupling error.

initialMzx - initial z-x cross coupling error.

initialMzy - initial z-y cross coupling error.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getHardIron

public double[] getHardIron()

Gets known hard-iron bias as an array. Array values are expressed in Teslas (T).

Specified by:

getHardIron in interface KnownHardIronMagnetometerCalibrator

Returns:

array containing coordinates of initial bias.

getHardIron

public void getHardIron(double[] result)

Gets known hard-iron bias as an array. Array values are expressed in Teslas (T).

Specified by:

getHardIron in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result data will be copied to.

Throws:

IllegalArgumentException - if provided array does not have length 3.

setHardIron

public void setHardIron(double[] hardIron)
                 throws com.irurueta.navigation.LockedException

Sets known hard-iron bias as an array. Array values are expressed in Teslas (T).

Specified by:

setHardIron in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIron - known hard-iron bias.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

IllegalArgumentException - if provided array does not have length 3.

getHardIronMatrix

public com.irurueta.algebra.Matrix getHardIronMatrix()

Gets known hard-iron bias as a column matrix.

Specified by:

getHardIronMatrix in interface KnownHardIronMagnetometerCalibrator

Returns:

hard-iron bias as a column matrix.

getHardIronMatrix

public void getHardIronMatrix(com.irurueta.algebra.Matrix result)

Gets known hard-iron bias as a column matrix.

Specified by:

getHardIronMatrix in interface KnownHardIronMagnetometerCalibrator

Parameters:

result - instance where result data will be copied to.

Throws:

IllegalArgumentException - if provided matrix is not 3x1.

setHardIron

public void setHardIron(com.irurueta.algebra.Matrix hardIron)
                 throws com.irurueta.navigation.LockedException

Sets known hard-iron bias.

Specified by:

setHardIron in interface KnownHardIronMagnetometerCalibrator

Parameters:

hardIron - magnetometer hard-iron bias to be set.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

IllegalArgumentException - if provided matrix is not 3x1.

getInitialMm

public com.irurueta.algebra.Matrix getInitialMm()

Gets initial scale factors and cross coupling errors matrix.

Specified by:

getInitialMm in interface MagnetometerNonLinearCalibrator

Returns:

initial scale factors and cross coupling errors matrix.

getInitialMm

public void getInitialMm(com.irurueta.algebra.Matrix result)

Gets initial scale factors and cross coupling errors matrix.

Specified by:

getInitialMm in interface MagnetometerNonLinearCalibrator

Parameters:

result - instance where data will be stored.

Throws:

IllegalArgumentException - if provided matrix is not 3x3.

setInitialMm

public void setInitialMm(com.irurueta.algebra.Matrix initialMm)
                  throws com.irurueta.navigation.LockedException

Sets initial scale factors and cross coupling errors matrix.

Specified by:

setInitialMm in interface MagnetometerNonLinearCalibrator

Parameters:

initialMm - initial scale factors and cross coupling errors matrix.

Throws:

IllegalArgumentException - if provided matrix is not 3x3.

com.irurueta.navigation.LockedException - if calibrator is currently running.

getMeasurements

public List<StandardDeviationFrameBodyMagneticFluxDensity> getMeasurements()

Gets a list of body magnetic flux density measurements taken at different frames (positions, orientations and velocities). If a single device IMU needs to be calibrated, typically all measurements are taken at the same position, with zero velocity and multiple orientations. However, if we just want to calibrate a given IMU model (e.g. obtain an average and less precise calibration for the IMU of a given phone model), we could take measurements collected throughout the planet at multiple positions while the phone remains static (e.g. while charging), hence each measurement position will change, velocity will remain zero and orientation will be typically constant at horizontal orientation while the phone remains on a flat surface.

Specified by:

getMeasurements in interface OrderedStandardDeviationFrameBodyMagneticFluxDensityMagnetometerCalibrator

Returns:

a collection of body magnetic flux density measurements taken at different frames (positions, orientations and velocities).

setMeasurements

public void setMeasurements(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)
                     throws com.irurueta.navigation.LockedException

Sets a list of body magnetic flux density measurements taken at different frames (positions, orientations and velocities). If a single device IMU needs to be calibrated, typically all measurements are taken at the same position, with zero velocity and multiple orientations. However, if we just want to calibrate the a given IMU model (e.g. obtain an average and less precise calibration for the IMU of a given phone model), we could take measurements collected throughout the planet at multiple positions while the phone remains static (e.g. while charging), hence each measurement position will change, velocity will remain zero and orientation will be typically constant at horizontal orientation while the phone remains on a flat surface.

Specified by:

setMeasurements in interface OrderedStandardDeviationFrameBodyMagneticFluxDensityMagnetometerCalibrator

Parameters:

measurements - collection of body magnetic flux density measurements taken at different frames (positions, orientations and velocities).

Throws:

com.irurueta.navigation.LockedException - if estimator is currently running.

getMeasurementType

public MagnetometerCalibratorMeasurementType getMeasurementType()

Indicates the type of measurement used by this calibrator.

Specified by:

getMeasurementType in interface MagnetometerCalibrator

Returns:

type of measurement used by this calibrator.

isOrderedMeasurementsRequired

public boolean isOrderedMeasurementsRequired()

Indicates whether this calibrator requires ordered measurements in a list or not.

Specified by:

isOrderedMeasurementsRequired in interface MagnetometerCalibrator

Returns:

true if measurements must be ordered, false otherwise.

isCommonAxisUsed

public boolean isCommonAxisUsed()

Indicates whether z-axis is assumed to be common for accelerometer, gyroscope and magnetometer. When enabled, this eliminates 3 variables from Mm (soft-iron) matrix.

Specified by:

isCommonAxisUsed in interface MagnetometerCalibrator

Returns:

true if z-axis is assumed to be common for accelerometer, gyroscope and magnetometer, false otherwise.

setCommonAxisUsed

public void setCommonAxisUsed(boolean commonAxisUsed)
                       throws com.irurueta.navigation.LockedException

Specifies whether z-axis is assumed to be common for accelerometer and gyroscope. When enabled, this eliminates 3 variables from Mm matrix.

Specified by:

setCommonAxisUsed in interface MagnetometerCalibrator

Parameters:

commonAxisUsed - true if z-axis is assumed to be common for accelerometer, gyroscope and magnetometer, false otherwise.

Throws:

com.irurueta.navigation.LockedException - if estimator is currently running.

getListener

public RobustKnownHardIronAndFrameMagnetometerCalibratorListener getListener()

Gets listener to handle events raised by this calibrator.

Returns:

listener to handle events raised by this calibrator.

setListener

public void setListener(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)
                 throws com.irurueta.navigation.LockedException

Sets listener to handle events raised by this calibrator.

Parameters:

listener - listener to handle events raised by this calibrator.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getMinimumRequiredMeasurements

public int getMinimumRequiredMeasurements()

Gets minimum number of required measurements.

Specified by:

getMinimumRequiredMeasurements in interface MagnetometerCalibrator

Returns:

minimum number of required measurements.

isReady

public boolean isReady()

Indicates whether calibrator is ready to start the estimator.

Specified by:

isReady in interface MagnetometerCalibrator

Returns:

true if calibrator is ready, false otherwise.

isRunning

public boolean isRunning()

Indicates whether calibrator is currently running or no.

Specified by:

isRunning in interface MagnetometerCalibrator

Returns:

true if calibrator is running, false otherwise.

getMagneticModel

public WorldMagneticModel getMagneticModel()

Gets Earth's magnetic model.

Returns:

Earth's magnetic model or null if not provided.

setMagneticModel

public void setMagneticModel(WorldMagneticModel magneticModel)
                      throws com.irurueta.navigation.LockedException

Sets Earth's magnetic model.

Parameters:

magneticModel - Earth's magnetic model to be set.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

isLinearCalibratorUsed

public boolean isLinearCalibratorUsed()

Indicates whether a linear calibrator is used or not for preliminary solutions.

Returns:

indicates whether a linear calibrator is used or not for preliminary solutions.

setLinearCalibratorUsed

public void setLinearCalibratorUsed(boolean linearCalibratorUsed)
                             throws com.irurueta.navigation.LockedException

Specifies whether a linear calibrator is used or not for preliminary solutions.

Parameters:

linearCalibratorUsed - indicates whether a linear calibrator is used or not for preliminary solutions.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

isPreliminarySolutionRefined

public boolean isPreliminarySolutionRefined()

Indicates whether preliminary solutions must be refined after an initial linear solution is found. If no initial solution is found using a linear solver, a non linear solver will be used regardless of this value using an average solution as the initial value to be refined.

Returns:

true if preliminary solutions must be refined after an initial linear solution, false otherwise.

setPreliminarySolutionRefined

public void setPreliminarySolutionRefined(boolean preliminarySolutionRefined)
                                   throws com.irurueta.navigation.LockedException

Specifies whether preliminary solutions must be refined after an initial linear solution is found. If no initial solution is found using a linear solver, a non linear solver will be used regardless of this value using an average solution as the initial value to be refined.

Parameters:

preliminarySolutionRefined - true if preliminary solutions must be refined after an initial linear solution, false otherwise.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getProgressDelta

public float getProgressDelta()

Returns amount of progress variation before notifying a progress change during calibration.

Returns:

amount of progress variation before notifying a progress change during calibration.

setProgressDelta

public void setProgressDelta(float progressDelta)
                      throws com.irurueta.navigation.LockedException

Sets amount of progress variation before notifying a progress change during calibration.

Parameters:

progressDelta - amount of progress variation before notifying a progress change during calibration.

Throws:

IllegalArgumentException - if progress delta is less than zero or greater than 1.

com.irurueta.navigation.LockedException - if calibrator is currently running.

getConfidence

public double getConfidence()

Returns amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%). The amount of confidence indicates the probability that the estimated result is correct. Usually this value will be close to 1.0, but not exactly 1.0.

Returns:

amount of confidence as a value between 0.0 and 1.0.

setConfidence

public void setConfidence(double confidence)
                   throws com.irurueta.navigation.LockedException

Sets amount of confidence expressed as a value between 0.0 and 1.0 (which is equivalent to 100%). The amount of confidence indicates the probability that the estimated result is correct. Usually this value will be close to 1.0, but not exactly 1.0.

Parameters:

confidence - confidence to be set as a value between 0.0 and 1.0.

Throws:

IllegalArgumentException - if provided value is not between 0.0 and 1.0.

com.irurueta.navigation.LockedException - if calibrator is currently running.

getMaxIterations

public int getMaxIterations()

Returns maximum allowed number of iterations. If maximum allowed number of iterations is achieved without converging to a result when calling calibrate(), a RobustEstimatorException will be raised.

Returns:

maximum allowed number of iterations.

setMaxIterations

public void setMaxIterations(int maxIterations)
                      throws com.irurueta.navigation.LockedException

Sets maximum allowed number of iterations. When the maximum number of iterations is exceeded, result will not be available, however an approximate result will be available for retrieval.

Parameters:

maxIterations - maximum allowed number of iterations to be set.

Throws:

IllegalArgumentException - if provided value is less than 1.

com.irurueta.navigation.LockedException - if calibrator is currently running.

getInliersData

public com.irurueta.numerical.robust.InliersData getInliersData()

Gets data related to inliers found after estimation.

Returns:

data related to inliers found after estimation.

isResultRefined

public boolean isResultRefined()

Indicates whether result must be refined using a non-linear solver over found inliers.

Returns:

true to refine result, false to simply use result found by robust estimator without further refining.

setResultRefined

public void setResultRefined(boolean refineResult)
                      throws com.irurueta.navigation.LockedException

Specifies whether result must be refined using a non-linear solver over found inliers.

Parameters:

refineResult - true to refine result, false to simply use result found by robust estimator without further refining.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

isCovarianceKept

public boolean isCovarianceKept()

Indicates whether covariance must be kept after refining result. This setting is only taken into account if result is refined.

Returns:

true if covariance must be kept after refining result, false otherwise.

setCovarianceKept

public void setCovarianceKept(boolean keepCovariance)
                       throws com.irurueta.navigation.LockedException

Specifies whether covariance must be kept after refining result. This setting is only taken into account if result is refined.

Parameters:

keepCovariance - true if covariance must be kept after refining result, false otherwise.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

getQualityScores

public double[] getQualityScores()

Returns quality scores corresponding to each measurement. The larger the score value the better the quality of the sample. This implementation always returns null. Subclasses using quality scores must implement proper behavior.

Specified by:

getQualityScores in interface QualityScoredMagnetometerCalibrator

Returns:

quality scores corresponding to each sample.

setQualityScores

public void setQualityScores(double[] qualityScores)
                      throws com.irurueta.navigation.LockedException

Sets quality scores corresponding to each measurement. The larger the score value the better the quality of the sample. This implementation makes no action. Subclasses using quality scores must implement proper behaviour.

Specified by:

setQualityScores in interface QualityScoredMagnetometerCalibrator

Parameters:

qualityScores - quality scores corresponding to each pair of matched points.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than minimum required samples.

com.irurueta.navigation.LockedException - if calibrator is currently running.

getEstimatedMm

public com.irurueta.algebra.Matrix getEstimatedMm()

Gets estimated magnetometer soft-iron matrix containing scale factors and cross coupling errors. This is the product of matrix Tm containing cross coupling errors and Km containing scaling factors. So tat:

     Mm = [sx    mxy  mxz] = Tm*Km
          [myx   sy   myz]
          [mzx   mzy  sz ]
 

Where:

     Km = [sx 0   0 ]
          [0  sy  0 ]
          [0  0   sz]
 

and

     Tm = [1          -alphaXy    alphaXz ]
          [alphaYx    1           -alphaYz]
          [-alphaZx   alphaZy     1       ]
 

Hence:

     Mm = [sx    mxy  mxz] = Tm*Km =  [sx             -sy * alphaXy   sz * alphaXz ]
          [myx   sy   myz]            [sx * alphaYx   sy              -sz * alphaYz]
          [mzx   mzy  sz ]            [-sx * alphaZx  sy * alphaZy    sz           ]
 

This instance allows any 3x3 matrix however, typically alphaYx, alphaZx and alphaZy are considered to be zero if the accelerometer z-axis is assumed to be the same as the body z-axis. When this is assumed, myx = mzx = mzy = 0 and the Mm matrix becomes upper diagonal:

     Mm = [sx    mxy  mxz]
          [0     sy   myz]
          [0     0    sz ]
 

Values of this matrix are unit-less.

Specified by:

getEstimatedMm in interface MagnetometerCalibrator

Returns:

estimated magnetometer soft-iron scale factors and cross coupling errors, or null if not available.

getEstimatedSx

public Double getEstimatedSx()

Gets estimated x-axis scale factor.

Specified by:

getEstimatedSx in interface MagnetometerCalibrator

Returns:

estimated x-axis scale factor or null if not available.

getEstimatedSy

public Double getEstimatedSy()

Gets estimated y-axis scale factor.

Specified by:

getEstimatedSy in interface MagnetometerCalibrator

Returns:

estimated y-axis scale factor or null if not available.

getEstimatedSz

public Double getEstimatedSz()

Gets estimated z-axis scale factor.

Specified by:

getEstimatedSz in interface MagnetometerCalibrator

Returns:

estimated z-axis scale factor or null if not available.

getEstimatedMxy

public Double getEstimatedMxy()

Gets estimated x-y cross-coupling error.

Specified by:

getEstimatedMxy in interface MagnetometerCalibrator

Returns:

estimated x-y cross-coupling error or null if not available.

getEstimatedMxz

public Double getEstimatedMxz()

Gets estimated x-z cross-coupling error.

Specified by:

getEstimatedMxz in interface MagnetometerCalibrator

Returns:

estimated x-z cross-coupling error or null if not available.

getEstimatedMyx

public Double getEstimatedMyx()

Gets estimated y-x cross-coupling error.

Specified by:

getEstimatedMyx in interface MagnetometerCalibrator

Returns:

estimated y-x cross-coupling error or null if not available.

getEstimatedMyz

public Double getEstimatedMyz()

Gets estimated y-z cross-coupling error.

Specified by:

getEstimatedMyz in interface MagnetometerCalibrator

Returns:

estimated y-z cross-coupling error or null if not available.

getEstimatedMzx

public Double getEstimatedMzx()

Gets estimated z-x cross-coupling error.

Specified by:

getEstimatedMzx in interface MagnetometerCalibrator

Returns:

estimated z-x cross-coupling error or null if not available.

getEstimatedMzy

public Double getEstimatedMzy()

Gets estimated z-y cross-coupling error.

Specified by:

getEstimatedMzy in interface MagnetometerCalibrator

Returns:

estimated z-y cross-coupling error or null if not available.

getEstimatedChiSq

public double getEstimatedChiSq()

Gets estimated chi square value.

Specified by:

getEstimatedChiSq in interface MagnetometerNonLinearCalibrator

Returns:

estimated chi square value.

getEstimatedChiSqDegreesOfFreedom

public int getEstimatedChiSqDegreesOfFreedom()

Gets estimated chi square degrees of freedom. Degrees of freedom is equal to the number of sampled data minus the number of estimated parameters.

Specified by:

getEstimatedChiSqDegreesOfFreedom in interface MagnetometerNonLinearCalibrator

Returns:

estimated degrees of freedom of chi square value

getEstimatedReducedChiSq

public double getEstimatedReducedChiSq()

Gets estimated reduced chi square value. This is equal to estimated chi square value divided by its degrees of freedom. Ideally this value should be close to 1.0, indicating that fit is optimal. A value larger than 1.0 indicates that fit is not good or noise has been underestimated, and a value smaller than 1.0 indicates that there is overfitting or noise has been overestimated.

Specified by:

getEstimatedReducedChiSq in interface MagnetometerNonLinearCalibrator

Returns:

estimated reduced chi square value

getEstimatedMse

public double getEstimatedMse()

Gets estimated mean square error respect to provided measurements.

Specified by:

getEstimatedMse in interface MagnetometerNonLinearCalibrator

Returns:

estimated mean square error respect to provided measurements.

getEstimatedP

public double getEstimatedP()

Gets estimated probability of finding a smaller chi square value expressed as a value between 0.0 and 1.0. The smaller the found chi square value is, the better the fit of the estimated parameters to the actual parameter. Thus, the smaller the chance of finding a smaller chi square value, then the better the estimated fit is.

Specified by:

getEstimatedP in interface MagnetometerNonLinearCalibrator

Returns:

estimated probability of finding a smaller chi square value.

getEstimatedQ

public double getEstimatedQ()

Gets estimated measure of quality of estimated fit as a value between 0.0 and 1.0. The larger the quality value is, the better the fit that has been estimated.

Specified by:

getEstimatedQ in interface MagnetometerNonLinearCalibrator

Returns:

estimated measure of quality of estimated fit.

getEstimatedCovariance

public com.irurueta.algebra.Matrix getEstimatedCovariance()

Gets estimated covariance matrix for estimated calibration parameters. Diagonal elements of the matrix contains variance for the following parameters (following indicated order): sx, sy, sz, mxy, mxz, myx, myz, mzx, mzy.

Specified by:

getEstimatedCovariance in interface MagnetometerNonLinearCalibrator

Returns:

estimated covariance matrix for estimated position.

getPreliminarySubsetSize

public int getPreliminarySubsetSize()

Gets size of subsets to be checked during robust estimation. This has to be at least MINIMUM_MEASUREMENTS.

Returns:

size of subsets to be checked during robust estimation.

setPreliminarySubsetSize

public void setPreliminarySubsetSize(int preliminarySubsetSize)
                              throws com.irurueta.navigation.LockedException

Sets size of subsets to be checked during robust estimation. This has to be at least MINIMUM_MEASUREMENTS.

Parameters:

preliminarySubsetSize - size of subsets to be checked during robust estimation.

Throws:

com.irurueta.navigation.LockedException - if calibrator is currently running.

IllegalArgumentException - if provided value is less than MINIMUM_MEASUREMENTS.

getMethod

public abstract com.irurueta.numerical.robust.RobustEstimatorMethod getMethod()

Returns method being used for robust estimation.

Returns:

method being used for robust estimation.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(boolean commonAxisUsed,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 boolean commonAxisUsed,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(double[] qualityScores,
 List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener,
 com.irurueta.numerical.robust.RobustEstimatorMethod method)

Creates a robust known frame magnetometer calibrator.

Parameters:

qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

method - robust estimator method.

Returns:

a robust known frame magnetometer calibrator.

Throws:

IllegalArgumentException - if provided quality scores length is smaller than 4 samples.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create()

Creates a robust known frame magnetometer calibrator using default robust method.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

listener - listener to handle events raised by this calibrator.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(boolean commonAxisUsed)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

Returns:

a robust known frame magnetometer calibrator.

create

public static RobustKnownHardIronAndFrameMagnetometerCalibrator create(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements,
 boolean commonAxisUsed,
 RobustKnownHardIronAndFrameMagnetometerCalibratorListener listener)

Creates a robust known frame magnetometer calibrator using default robust method.

Parameters:

measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).

commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.

listener - listener to handle events raised by this calibrator.

Returns:

a robust known frame magnetometer calibrator.

setupWmmEstimator

protected void setupWmmEstimator()
                          throws IOException

Setups World Magnetic Model estimator.

Throws:

IOException - if model cannot be loaded.

computeError

protected double computeError(StandardDeviationFrameBodyMagneticFluxDensity measurement,
 com.irurueta.algebra.Matrix preliminaryResult)

Computes error of a preliminary result respect a given measurement.

Parameters:

measurement - a measurement.

preliminaryResult - a preliminary result.

Returns:

computed error.

computePreliminarySolutions

protected void computePreliminarySolutions(int[] samplesIndices,
 List<com.irurueta.algebra.Matrix> solutions)

Computes a preliminary solution for a subset of samples picked by a robust estimator.

Parameters:

samplesIndices - indices of samples picked by the robust estimator.

solutions - list where estimated preliminary solution will be stored.

attemptRefine

protected void attemptRefine(com.irurueta.algebra.Matrix preliminaryResult)

Attempts to refine calibration parameters if refinement is requested. This method returns a refined solution or provided input if refinement is not requested or has failed. If refinement is enabled and it is requested to keep covariance, this method will also keep covariance of refined position.

Parameters:

preliminaryResult - a preliminary result.

convertMagneticFluxDensity

private static double convertMagneticFluxDensity(double value,
 com.irurueta.units.MagneticFluxDensityUnit unit)

Converts magnetic flux density value and unit to Teslas.

Parameters:

value - magnetic flux density value.

unit - unit of magnetic flux density value.

Returns:

converted value.

convertMagneticFluxDensity

private static double convertMagneticFluxDensity(com.irurueta.units.MagneticFluxDensity magneticFluxDensity)

Converts magnetic flux density instance to Teslas.

Parameters:

magneticFluxDensity - magnetic flux density instance to be converted.

Returns:

converted value.