/home/travis/build/lis-epfl/MAVRIC_Library/sensing/ahrs_qfilter.hpp

/*******************************************************************************
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/*******************************************************************************
 * \file qfilter.h
 *
 * \author MAV'RIC Team
 * \author Felix Schill
 *
 * \brief This file implements a complementary filter for the attitude estimation
 *
 ******************************************************************************/


#ifndef QFILTER_HPP_
#define QFILTER_HPP_

#include <cstdint>

#include "sensing/ahrs.hpp"
#include "sensing/imu.hpp"


class AHRS_qfilter: public AHRS
{
public:
    struct conf_t
    {
        float   kp;                             
        float   ki;                             
        float   kp_mag;                         
        float   ki_mag;                         
    };


    static inline conf_t default_config()
    {
        conf_t conf = {};

        conf.kp             = 0.07f;
        conf.ki             = 0.0f;
        conf.kp_mag         = 0.1f;
        conf.ki_mag         = 0.0f;

        return conf;
    };


    AHRS_qfilter(const Imu& imu, const conf_t& config = default_config());


    bool update(void);


    float last_update_s(void) const;


    bool is_healthy(void) const;


    quat_t attitude(void) const;


    std::array<float,3> angular_speed(void) const;


    std::array<float,3> linear_acceleration(void) const;


protected:
    const Imu&  imu_;        

    quat_t              attitude_;              
    std::array<float,3> angular_speed_;         
    std::array<float,3> linear_acc_;            
    float               last_update_s_;         

private:
    ahrs_state_t internal_state_;

    float   kp_;             
    float   ki_;             
    float   kp_mag_;         
    float   ki_mag_;         

    float time_s_;           

    std::array<float, 3> gyro_bias_;    
};

#endif /* QFILTER_HPP_ */