Class PROSACRobustKnownFrameMagnetometerCalibrator

java.lang.Object
com.irurueta.navigation.inertial.calibration.magnetometer.RobustKnownFrameMagnetometerCalibrator
com.irurueta.navigation.inertial.calibration.magnetometer.PROSACRobustKnownFrameMagnetometerCalibrator
All Implemented Interfaces:
MagnetometerCalibrator, MagnetometerNonLinearCalibrator, OrderedStandardDeviationFrameBodyMagneticFluxDensityMagnetometerCalibrator, QualityScoredMagnetometerCalibrator, UnknownHardIronMagnetometerCalibrator, UnknownHardIronNonLinearMagnetometerCalibrator

public class PROSACRobustKnownFrameMagnetometerCalibrator extends RobustKnownFrameMagnetometerCalibrator
Robustly estimates magnetometer hard-iron biases, soft-iron cross couplings and scaling factors using PROSAC algorithm.

To use this calibrator at least 4 measurements at different known frames must be provided. In other words, magnetometer samples must be obtained at 4 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 Details

    • DEFAULT_THRESHOLD

      public static final double DEFAULT_THRESHOLD
      Constant defining default threshold to determine whether samples are inliers or not.
      See Also:
    • MIN_THRESHOLD

      public static final double MIN_THRESHOLD
      Minimum value that can be set as threshold. Threshold must be strictly greater than 0.0.
      See Also:
    • DEFAULT_COMPUTE_AND_KEEP_INLIERS

      public static final boolean DEFAULT_COMPUTE_AND_KEEP_INLIERS
      Indicates that by default inliers will only be computed but not kept.
      See Also:
    • DEFAULT_COMPUTE_AND_KEEP_RESIDUALS

      public static final boolean DEFAULT_COMPUTE_AND_KEEP_RESIDUALS
      Indicates that by default residuals will only be computed but not kept.
      See Also:
    • threshold

      private double threshold
      Threshold to determine whether samples are inliers or not when testing possible solutions. The threshold refers to the amount of error on distance between estimated position and distances provided for each sample.
    • computeAndKeepInliers

      private boolean computeAndKeepInliers
      Indicates whether inliers must be computed and kept.
    • computeAndKeepResiduals

      private boolean computeAndKeepResiduals
      Indicates whether residuals must be computed and kept.
    • qualityScores

      private double[] qualityScores
      Quality scores corresponding to each provided sample. The larger the score value the better the quality of the sample.
  • Constructor Details

    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator()
      Constructor.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(RobustKnownFrameMagnetometerCalibratorListener listener)
      Constructor.
      Parameters:
      listener - listener to be notified of events such as when estimation starts, ends or its progress significantly changes.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)
      Constructor.
      Parameters:
      measurements - list of body magnetic flux density measurements with standard deviations taken at different frames (positions and orientations).
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownFrameMagnetometerCalibratorListener 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.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(boolean commonAxisUsed)
      Constructor.
      Parameters:
      commonAxisUsed - indicates whether z-axis is assumed to be common for the accelerometer, gyroscope and magnetometer.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(boolean commonAxisUsed, RobustKnownFrameMagnetometerCalibratorListener 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.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(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.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownFrameMagnetometerCalibratorListener 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.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores)
      Constructor.
      Parameters:
      qualityScores - quality scores corresponding to each provided measurement. The larger the score value the better the quality of the sample.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, RobustKnownFrameMagnetometerCalibratorListener listener)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements)
      Constructor.
      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).
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, RobustKnownFrameMagnetometerCalibratorListener listener)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, boolean commonAxisUsed)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, boolean commonAxisUsed, RobustKnownFrameMagnetometerCalibratorListener listener)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
    • PROSACRobustKnownFrameMagnetometerCalibrator

      public PROSACRobustKnownFrameMagnetometerCalibrator(double[] qualityScores, List<StandardDeviationFrameBodyMagneticFluxDensity> measurements, boolean commonAxisUsed, RobustKnownFrameMagnetometerCalibratorListener listener)
      Constructor.
      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.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.
  • Method Details

    • getThreshold

      public double getThreshold()
      Gets threshold to determine whether samples are inliers or not when testing possible solutions. The threshold refers to the amount of error on norm between measured specific forces and the ones generated with estimated calibration parameters provided for each sample.
      Returns:
      threshold to determine whether samples are inliers or not.
    • setThreshold

      public void setThreshold(double threshold) throws com.irurueta.navigation.LockedException
      Sets threshold to determine whether samples are inliers or not when testing possible solutions. The threshold refers to the amount of error on norm between measured specific forces and the ones generated with estimated calibration parameters provided for each sample.
      Parameters:
      threshold - threshold to determine whether samples are inliers or not.
      Throws:
      IllegalArgumentException - if provided value is equal or less than zero.
      com.irurueta.navigation.LockedException - if calibrator is currently running.
    • getQualityScores

      public double[] getQualityScores()
      Returns quality scores corresponding to each provided sample. The larger the score value the better the quality of the sample.
      Specified by:
      getQualityScores in interface QualityScoredMagnetometerCalibrator
      Overrides:
      getQualityScores in class RobustKnownFrameMagnetometerCalibrator
      Returns:
      quality scores corresponding to each sample.
    • setQualityScores

      public void setQualityScores(double[] qualityScores) throws com.irurueta.navigation.LockedException
      Sets quality scores corresponding to each provided sample. The larger the score value the better the quality of the sample.
      Specified by:
      setQualityScores in interface QualityScoredMagnetometerCalibrator
      Overrides:
      setQualityScores in class RobustKnownFrameMagnetometerCalibrator
      Parameters:
      qualityScores - quality scores corresponding to each sample.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than minimum required samples.
      com.irurueta.navigation.LockedException - if calibrator is currently running.
    • isReady

      public boolean isReady()
      Indicates whether calibrator is ready to find a solution.
      Specified by:
      isReady in interface MagnetometerCalibrator
      Overrides:
      isReady in class RobustKnownFrameMagnetometerCalibrator
      Returns:
      true if calibrator is ready, false otherwise.
    • isComputeAndKeepInliersEnabled

      public boolean isComputeAndKeepInliersEnabled()
      Indicates whether inliers must be computed and kept.
      Returns:
      true if inliers must be computed and kept, false if inliers only need to be computed but not kept.
    • setComputeAndKeepInliersEnabled

      public void setComputeAndKeepInliersEnabled(boolean computeAndKeepInliers) throws com.irurueta.navigation.LockedException
      Specifies whether inliers must be computed and kept.
      Parameters:
      computeAndKeepInliers - true if inliers must be computed and kept, false if inliers only need to be computed but not kept.
      Throws:
      com.irurueta.navigation.LockedException - if calibrator is currently running.
    • isComputeAndKeepResiduals

      public boolean isComputeAndKeepResiduals()
      Indicates whether residuals must be computed and kept.
      Returns:
      true if residuals must be computed and kept, false if residuals only need to be computed but not kept.
    • setComputeAndKeepResidualsEnabled

      public void setComputeAndKeepResidualsEnabled(boolean computeAndKeepResiduals) throws com.irurueta.navigation.LockedException
      Specifies whether residuals must be computed and kept.
      Parameters:
      computeAndKeepResiduals - true if residuals must be computed and kept, false if residuals only need to be computed but not kept.
      Throws:
      com.irurueta.navigation.LockedException - if calibrator is currently running.
    • calibrate

      public void calibrate() throws com.irurueta.navigation.LockedException, com.irurueta.navigation.NotReadyException, CalibrationException
      Estimates magnetometer calibration parameters containing hard-iron bias and soft-iron scale factors and cross-coupling errors.
      Throws:
      com.irurueta.navigation.LockedException - if calibrator is currently running.
      com.irurueta.navigation.NotReadyException - if calibrator is not ready.
      CalibrationException - if estimation fails for numerical reasons.
    • getMethod

      public com.irurueta.numerical.robust.RobustEstimatorMethod getMethod()
      Returns method being used for robust estimation.
      Specified by:
      getMethod in class RobustKnownFrameMagnetometerCalibrator
      Returns:
      method being used for robust estimation.
    • isQualityScoresRequired

      public boolean isQualityScoresRequired()
      Indicates whether this calibrator requires quality scores for each measurement or not.
      Returns:
      true if quality scores are required, false otherwise.
    • internalSetQualityScores

      private void internalSetQualityScores(double[] qualityScores)
      Sets quality scores corresponding to each provided sample. This method is used internally and does not check whether instance is locked or not.
      Parameters:
      qualityScores - quality scores to be set.
      Throws:
      IllegalArgumentException - if provided quality scores length is smaller than 4 samples.