INDI::MadgwickFilter Class Reference

Madgwick AHRS filter (9-DOF and 6-DOF). More...

#include <imusensorfusion.h>

Inheritance diagram for INDI::MadgwickFilter:

Public Member Functions
	MadgwickFilter (double beta=0.1)
virtual	~MadgwickFilter ()=default
void	update (double gx, double gy, double gz, double ax, double ay, double az, double mx, double my, double mz, double dt, bool useMag=true) override
	Perform one filter update step.
void	getQuaternion (double &w, double &i, double &j, double &k) const override
	Return the current orientation quaternion.
void	reset () override
	Reset the filter to the identity quaternion.
void	setBeta (double beta)
	Set the filter gain β.
double	getBeta () const
Public Member Functions inherited from INDI::IMUSensorFusion
virtual	~IMUSensorFusion ()=default

Detailed Description

Madgwick AHRS filter (9-DOF and 6-DOF).

A computationally efficient gradient-descent based orientation filter. A single tuning parameter β (beta) controls the trade-off between gyroscope integration accuracy and accelerometer/magnetometer correction:

• Larger β → faster convergence to accelerometer/mag, more noise
• Smaller β → slower convergence, smoother but slower to correct drift

Recommended starting value: β = 0.1 for astronomical applications.

Reference: Madgwick, S.O.H. (2010) "An efficient orientation filter for inertial and inertial/magnetic sensor arrays"

Definition at line 99 of file imusensorfusion.h.

Constructor & Destructor Documentation

MadgwickFilter()

INDI::MadgwickFilter::MadgwickFilter ( double  beta = 0.1 )

explicit

Parameters

beta	Algorithm gain β. Controls gyroscope measurement error (rad/s). Default 0.1 is suitable for slow-moving astronomical applications.

Definition at line 37 of file imusensorfusion.cpp.

~MadgwickFilter()

virtual INDI::MadgwickFilter::~MadgwickFilter ( )

virtualdefault

Member Function Documentation

getBeta()

double INDI::MadgwickFilter::getBeta ( ) const

inline

Definition at line 124 of file imusensorfusion.h.

getQuaternion()

void INDI::MadgwickFilter::getQuaternion ( double &  w, double &  i, double &  j, double &  k  ) const

overridevirtual

Return the current orientation quaternion.

Parameters

w	Scalar (real) component
i	Vector X component
j	Vector Y component
k	Vector Z component

Implements INDI::IMUSensorFusion.

Definition at line 50 of file imusensorfusion.cpp.

reset()

void INDI::MadgwickFilter::reset ( )

overridevirtual

Reset the filter to the identity quaternion.

Implements INDI::IMUSensorFusion.

Definition at line 42 of file imusensorfusion.cpp.

setBeta()

void INDI::MadgwickFilter::setBeta ( double  beta )

inline

Set the filter gain β.

Definition at line 120 of file imusensorfusion.h.

update()

void INDI::MadgwickFilter::update ( double  gx, double  gy, double  gz, double  ax, double  ay, double  az, double  mx, double  my, double  mz, double  dt, bool  useMag = true  )

overridevirtual

Perform one filter update step.

Parameters

gx	Gyroscope X-axis angular rate (rad/s)
gy	Gyroscope Y-axis angular rate (rad/s)
gz	Gyroscope Z-axis angular rate (rad/s)
ax	Accelerometer X-axis (m/s² or any unit — only direction used)
ay	Accelerometer Y-axis
az	Accelerometer Z-axis
mx	Magnetometer X-axis (µT or any consistent unit)
my	Magnetometer Y-axis
mz	Magnetometer Z-axis
dt	Time step in seconds since last update
useMag	If false the magnetometer data is ignored (6-DOF mode)

Implements INDI::IMUSensorFusion.

Definition at line 58 of file imusensorfusion.cpp.

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The documentation for this class was generated from the following files:

• imusensorfusion.h
• imusensorfusion.cpp