/home/travis/build/lis-epfl/MAVRIC_Library/control/pid_controller.hpp

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/*******************************************************************************
 * \file pid_control.hpp
 *
 * \author MAV'RIC Team
 * \author Felix Schill
 *
 * \brief PID controller
 *
 ******************************************************************************/


#ifndef PID_CONTROL_HPP_
#define PID_CONTROL_HPP_

#include <cstdint>
#include <cstdbool>
#include <math.h>


typedef struct
{
    float gain;         
    float accumulator;  
    float clip_pre;     
    float clip;         
} integrator_t;


typedef struct
{
    float gain;         
    float previous;     
    float clip;         
} differentiator_t;


typedef struct
{
    float p_gain;
    float clip_min;                     
    float clip_max;                     
    integrator_t integrator;            
    differentiator_t differentiator;    
    float soft_zone_width;              
} pid_controller_conf_t;


typedef struct
{
    float p_gain;                       
    float clip_min;                     
    float clip_max;                     
    integrator_t integrator;            
    differentiator_t differentiator;    
    float output;                       
    float error;                        
    float last_update_s;                
    float dt_s;                         
    float soft_zone_width;              
    bool is_saturated;                  
} pid_controller_t;


bool pid_controller_init(pid_controller_t* controller, const pid_controller_conf_t* config);


bool pid_controller_apply_config(pid_controller_t* controller, const pid_controller_conf_t* config);


void pid_controller_init_pass_through(pid_controller_t* controller);


void pid_controller_reset_integrator(pid_controller_t* controller);


float pid_controller_update(pid_controller_t* controller, float error);


float pid_controller_update_dt(pid_controller_t* controller, float error, float dt);


#endif /* PID_CONTROL_HPP_ */