Code for science olympiad electric vehicle in Arduino

Electric_vehicle

#include <Servo.h>

// pin defs
#define EncoderPinA 2  //  (green)
#define EncoderPinB 3  //  (white)

#define ButtonPin 12  //  (start btn SW) 

const int pwmPin = 5; // motor white wire
const int ledPin = 13; // onboard LED

Servo motor;

volatile long encoderPosition = 0;
const float cmTarget = 900-(100);
// overshot calculations (approx)
// 3m - 70cm overshot
const float rotationsTarget = (cmTarget / 8); // 1rot = approx 8cm
const int motorSpeed = 1200; // Constant speed PWM value

bool motorStarted = false; // track buttonpress

void setup() {
  // Encoder setup
  pinMode(EncoderPinA, INPUT_PULLUP);
  pinMode(EncoderPinB, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(EncoderPinA), EncoderA, FALLING);
  attachInterrupt(digitalPinToInterrupt(EncoderPinB), EncoderB, FALLING);
  
  motor.attach(pwmPin);
  motor.writeMicroseconds(800); // initialize motor to minimum PWM
  
  pinMode(ButtonPin, INPUT_PULLUP); // track the button
  
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  
  Serial.begin(9600);
  delay(2000); // let esc get ready
}

void loop() {
  // start pressed
  if (digitalRead(ButtonPin) == LOW && !motorStarted) {
    motor.writeMicroseconds(motorSpeed);  
    motorStarted = true; 
    digitalWrite(ledPin, HIGH); 
  }
  
  // Run motor at constant speed or stop it based on encoder position
  if (motorStarted) {
    float rotations = (float)encoderPosition / 720.0; 
  
    if (rotations < rotationsTarget) {
      motor.writeMicroseconds(motorSpeed);
    } else {
      // stop motor when target rotations reached
      motor.writeMicroseconds(800);
      digitalWrite(ledPin, LOW); 
    }
  
    static unsigned long lastPrintTime = 0;
    if (millis() - lastPrintTime >= 100) {
      Serial.print("Rotations: ");
      Serial.print(rotations, 2); 
      Serial.print(", Dist: ");
      Serial.println(rotations/8, 2); 

      lastPrintTime = millis();
    }
  }
}

void EncoderA() {
  encoderPosition += (digitalRead(EncoderPinA) == digitalRead(EncoderPinB)) ? -1 : 1;
}

void EncoderB() {
  encoderPosition += (digitalRead(EncoderPinA) != digitalRead(EncoderPinB)) ? -1 : 1;
}