mrm-pid.h

#pragma once
#include "Arduino.h"
 
#define PrintSpeed // If defined, a speed calculation will be displayed.
 
class Mrm_pid
{
    float cumulativeValue = 0;
    float derivative; // A derivative component, depends on error change (not on error value). 
                      // For example, if a robot follows a line and the line is the below robot's center (error 0), it will not mean that we will not have to 
                      // correct the robots direction. If, at that moment, the robot is turning sharply to the left (but the current error is the mentioned 0), You will
                      // have to set the motors' speed so that the robot turns to the right. It will not turn to the right as it has a big rotational
                      // speed to the left, but the speed will be reduced. By doing nothing, robot would turn to much to the left. The proportional 
                      // component would start to influence the motion but it would be too late - You would see a periodic left - right rotation.
    float integrative; // Integral component, corrects a long term error. For example when left motors are stronger causing the robot to go more to the right, when it should go straight.
    unsigned long lastCalcuationAtMicros = micros();
    float lastValue = 0;
    float proportional; // Proportional component. A bigger error causes a bigger correction. 
    HardwareSerial * serial; //Additional serial port
    
    void print(String message, bool eol = false);
 
public:
    Mrm_pid(float proportionalComponent, float derivativeComponent, float integrativeComponent, HardwareSerial * hardwareSerial = 0);
 
    float calculate(float inputValue, bool verbose = false);
};