pid_controller.h

/*******************************************************************************
 * Copyright (c) 2009-2014, MAV'RIC Development Team
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/*******************************************************************************
 * \file pid_control.h
 * 
 * \author MAV'RIC Team
 * \author Felix Schill
 *   
 * \brief PID controller
 *
 ******************************************************************************/


#ifndef PID_CONTROL_H_
#define PID_CONTROL_H_

#ifdef __cplusplus
extern "C" {
#endif

#include <stdint.h>
#include <math.h>


typedef struct 
{
    float pregain;      
    float postgain;     
    float accumulator;  
    float clip;         
} integrator_t;


typedef struct 
{
    float gain;         
    float previous;     
    float LPF;          
    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;                        
    uint32_t last_update;               
    float dt;                           
    float soft_zone_width;              
} pid_controller_t;


void pid_controller_init(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);


#ifdef __cplusplus
}
#endif

#endif /* PID_CONTROL_H_ */