03.2_Automatic_Tracking_Line.ino

#include "Freenove_4WD_Car_for_Arduino.h"

#define TK_STOP_SPEED          0
#define TK_FORWARD_SPEED        (90 + tk_VoltageCompensationToSpeed    )

//define different speed levels
#define TK_TURN_SPEED_LV4       (180 + tk_VoltageCompensationToSpeed   )
#define TK_TURN_SPEED_LV3       (150 + tk_VoltageCompensationToSpeed   )
#define TK_TURN_SPEED_LV2       (-140 + tk_VoltageCompensationToSpeed  )
#define TK_TURN_SPEED_LV1       (-160 + tk_VoltageCompensationToSpeed  )

int tk_VoltageCompensationToSpeed;  //define Voltage Speed Compensation

void setup() {

  Serial.begin(9600);
  Serial.setTimeout(200);

  pinsSetup(); //set up pins
  getTrackingSensorVal();//Calculate Voltage speed Compensation
}

void loop() {

  //while (Serial.available() == 0) { }
  String trackingSensorVal = Serial.readString();
  
  switch (trackingSensorVal.toInt())
  {
    case 4:   //000
      motorRun(TK_FORWARD_SPEED, TK_FORWARD_SPEED); //car move forward
      break;
    case 0:   //111
      motorRun(TK_STOP_SPEED, TK_STOP_SPEED); //car stop
      break;
    case 10:   //001
      motorRun(TK_TURN_SPEED_LV4, TK_TURN_SPEED_LV1); //car turn
      break;
    case 2:   //011
      motorRun(TK_TURN_SPEED_LV3, TK_TURN_SPEED_LV2); //car turn right
      delay(6000);
      break;
    case 1:   //010
      motorRun(TK_TURN_SPEED_LV2, TK_TURN_SPEED_LV3); //car turn left
      delay(2000);
      break;
    default:
      motorRun(TK_TURN_SPEED_LV2, TK_TURN_SPEED_LV3); //car turn left
      delay(2000);
      break;
  }
}

void tk_CalculateVoltageCompensation() {
  getBatteryVoltage();
  float voltageOffset = 7 - batteryVoltage;
  tk_VoltageCompensationToSpeed = 30 * voltageOffset;
}

//when black line on one side is detected, the value of the side will be 0, or the value is 1  
u8 getTrackingSensorVal() {
  u8 trackingSensorVal = 0;
  trackingSensorVal = (digitalRead(PIN_TRACKING_LEFT) == 1 ? 1 : 0) << 2 | (digitalRead(PIN_TRACKING_CENTER) == 1 ? 1 : 0) << 1 | (digitalRead(PIN_TRACKING_RIGHT) == 1 ? 1 : 0) << 0;
  return trackingSensorVal;
}