#include <ESP32Servo.h>
#define TRIG_PIN 5
#define ECHO_PIN 18
#define SERVO_PIN 15
Servo gateServo;
long duration;
float distance;
void setup() {
  Serial.begin(115200);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  gateServo.attach(SERVO_PIN);
  gateServo.write(0); 
}
float readDistance() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2; 
  return distance;
}
void loop() {
  float d = readDistance();
  Serial.print("Distance: ");
  Serial.println(d);

  if (d < 20) {         
    gateServo.write(90); 
  } else {
    gateServo.write(0);  
  }
  delay(500);
}