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/**
* @file KalmanNav.hpp
*
* kalman filter navigation code
*/
#pragma once
//#define MATRIX_ASSERT
//#define VECTOR_ASSERT
#include <nuttx/config.h>
#include <mathlib/mathlib.h>
#include <controllib/blocks.hpp>
#include <controllib/block/BlockParam.hpp>
#include <controllib/block/UOrbSubscription.hpp>
#include <controllib/block/UOrbPublication.hpp>
#include <uORB/topics/vehicle_attitude.h>
#include <uORB/topics/vehicle_global_position.h>
#include <uORB/topics/sensor_combined.h>
#include <uORB/topics/vehicle_gps_position.h>
#include <uORB/topics/parameter_update.h>
#include <drivers/drv_hrt.h>
#include <poll.h>
#include <unistd.h>
/**
* Kalman filter navigation class
* http://en.wikipedia.org/wiki/Extended_Kalman_filter
* Discrete-time extended Kalman filter
*/
class KalmanNav : public control::SuperBlock
{
public:
/**
* Constructor
*/
KalmanNav(SuperBlock *parent, const char *name);
/**
* Deconstuctor
*/
virtual ~KalmanNav() {};
/**
* The main callback function for the class
*/
void update();
/**
* Publication update
*/
virtual void updatePublications();
/**
* State prediction
* Continuous, non-linear
*/
void predictState(float dt);
/**
* State covariance prediction
* Continuous, linear
*/
void predictStateCovariance(float dt);
/**
* Attitude correction
*/
void correctAtt();
/**
* Position correction
*/
void correctPos();
/**
* Overloaded update parameters
*/
virtual void updateParams();
protected:
// kalman filter
math::Matrix F; /**< Jacobian(f,x), where dx/dt = f(x,u) */
math::Matrix G; /**< noise shaping matrix for gyro/accel */
math::Matrix P; /**< state covariance matrix */
math::Matrix P0; /**< initial state covariance matrix */
math::Matrix V; /**< gyro/ accel noise matrix */
math::Matrix HAtt; /**< attitude measurement matrix */
math::Matrix RAtt; /**< attitude measurement noise matrix */
math::Matrix HPos; /**< position measurement jacobian matrix */
math::Matrix RPos; /**< position measurement noise matrix */
// attitude
math::Dcm C_nb; /**< direction cosine matrix from body to nav frame */
math::Quaternion q; /**< quaternion from body to nav frame */
// subscriptions
control::UOrbSubscription<sensor_combined_s> _sensors; /**< sensors sub. */
control::UOrbSubscription<vehicle_gps_position_s> _gps; /**< gps sub. */
control::UOrbSubscription<parameter_update_s> _param_update; /**< parameter update sub. */
// publications
control::UOrbPublication<vehicle_global_position_s> _pos; /**< position pub. */
control::UOrbPublication<vehicle_attitude_s> _att; /**< attitude pub. */
// time stamps
uint64_t _pubTimeStamp; /**< output data publication time stamp */
uint64_t _predictTimeStamp; /**< prediction time stamp */
uint64_t _attTimeStamp; /**< attitude correction time stamp */
uint64_t _outTimeStamp; /**< output time stamp */
// frame count
uint16_t _navFrames; /**< navigation frames completed in output cycle */
// miss counts
uint16_t _miss; /**< number of times fast prediction loop missed */
// accelerations
float fN, fE, fD; /**< navigation frame acceleration */
// states
enum {PHI = 0, THETA, PSI, VN, VE, VD, LAT, LON, ALT}; /**< state enumeration */
float phi, theta, psi; /**< 3-2-1 euler angles */
float vN, vE, vD; /**< navigation velocity, m/s */
double lat, lon, alt; /**< lat, lon, alt, radians */
// parameters
control::BlockParam<float> _vGyro; /**< gyro process noise */
control::BlockParam<float> _vAccel; /**< accelerometer process noise */
control::BlockParam<float> _rMag; /**< magnetometer measurement noise */
control::BlockParam<float> _rGpsVel; /**< gps velocity measurement noise */
control::BlockParam<float> _rGpsPos; /**< gps position measurement noise */
control::BlockParam<float> _rGpsAlt; /**< gps altitude measurement noise */
control::BlockParam<float> _rAccel; /**< accelerometer measurement noise */
control::BlockParam<float> _magDip; /**< magnetic inclination with level */
control::BlockParam<float> _magDec; /**< magnetic declination, clockwise rotation */
control::BlockParam<float> _g; /**< gravitational constant */
control::BlockParam<float> _faultPos; /**< fault detection threshold for position */
control::BlockParam<float> _faultAtt; /**< fault detection threshold for attitude */
// status
bool _positionInitialized; /**< status, if position has been init. */
// accessors
int32_t getLatDegE7() { return int32_t(lat * 1.0e7 * M_RAD_TO_DEG); }
void setLatDegE7(int32_t val) { lat = val / 1.0e7 / M_RAD_TO_DEG; }
int32_t getLonDegE7() { return int32_t(lon * 1.0e7 * M_RAD_TO_DEG); }
void setLonDegE7(int32_t val) { lon = val / 1.0e7 / M_RAD_TO_DEG; }
int32_t getAltE3() { return int32_t(alt * 1.0e3); }
void setAltE3(int32_t val) { alt = double(val) / 1.0e3; }
};
