px4-firmware/EKF/ekf.h

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/**
 * @file ekf.h
 * Class for core functions for ekf attitude and position estimator.
 *
 * @author Roman Bast <bapstroman@gmail.com>
 *
 */

#include "estimator_base.h"

class Ekf : public EstimatorBase
{
public:

	Ekf();
	~Ekf();

	void update();

private:

	static const uint8_t _kNumStates = 24;
	bool _filter_initialised;

	bool _fuse_height;	// true if there is new baro data
	bool _fuse_pos;		// true if there is new position data from gps
	bool _fuse_vel;		// true if there is new velocity data from gps

	float P[_kNumStates][_kNumStates];	// state covariance matrix

	bool initialiseFilter(void);

	void initialiseCovariance();

	void predictState();

	void predictCovariance();

	void fusePosVel();

	void fuseMag();

	void fuseAirspeed();

	void fuseRange();

	void resetVelocity();

	void resetPosition();


};