pid.h

Go to the documentation of this file.

 
#ifndef PID_H // Include guard.
#define PID_H
 
#include "pathfinding/maze.h"
 
// Definitions.
// -----------------------------------------------------------------------------
//
 
#define PID_ENCODER_STEP_TURN_90_DEG 18
#define PID_ENCODER_STEP_TURN_180_DEG 36
#define PID_ENCODER_STEP_MOVE 25
#define PID_ENCODER_CENTER_OFFSET 5 // End of pid_encoder_constants group.
 
#define PID_KP 0.01f
#define PID_KI 0.05f
#define PID_KD 0.01f
#define PID_EPSILON 0.01f
#define PID_RATIO_TO_BEARING -0.035f
#define PID_ENCODER_PIN 21
#define PID_BIAS_LEFT_RATIO 1.05f
 // End of pid_constants group.
 
#define PID_DEGREES_NORMALISE(x) ((x + 180) % 360 - 180) // Normalise degrees.
 
// Type definitions.
// -----------------------------------------------------------------------------
//
 
typedef struct pid_params
{
    float k_p;              
    float k_i;              
    float k_d;              
    float epsilon;          
    float ratio_to_bearing; 
    float setpoint;         
    float integral;         
    float prev_error;       
    float current_ratio;    
    float current_bearing;  
} pid_params_t;
 
typedef struct pid_turn_params
{
    uint b_is_turning;       
    uint encoder_step_count; 
    char turn_direction;     
    uint b_is_centered;      
    uint b_is_turn_complete; 
    uint b_is_moved_cell;    
} pid_turn_params_t;
 
// Public function declarations.
// -----------------------------------------------------------------------------
//
 
void  pid_init_error_correction(pid_params_t *p_pid_params);
void  pid_init_structs(pid_turn_params_t *p_turn_params);
void  pid_navigate_turn(pid_turn_params_t        *p_turn_params,
                        maze_cardinal_direction_t direction);
float pid_calculate_correction(float         current_bearing,
                               float         target_bearing,
                               float         current_ratio,
                               pid_params_t *p_pid_params);
void  pid_bearing_correction(float         target_bearing,
                             float         current_bearing,
                             pid_params_t *p_pid_params);
 
#endif // PID_H
 
// End of file pid.h