/*
 * This ESP32 code is created by esp32io.com
 *
 * This ESP32 code is released in the public domain
 *
 * For more detail (instruction and wiring diagram), visit https://esp32io.com/tutorials/esp32-ultrasonic-sensor
 */

#define TRIG_PIN 18 // ESP32 pin GIOP23 connected to Ultrasonic Sensor's TRIG pin
#define ECHO_PIN 5 // ESP32 pin GIOP22 connected to Ultrasonic Sensor's ECHO pin
float duration_us, distance_cm;
#include <ESP32Servo.h>

const int servoPin = 19;
Servo servo;

void setup() {
  servo.attach(servoPin, 500, 2400);
  // begin serial port
  Serial.begin (9600);

  // configure the trigger pin to output mode
  pinMode(TRIG_PIN, OUTPUT);
  // configure the echo pin to input mode
  pinMode(ECHO_PIN, INPUT);
}
int pos=0;

void loop() {
  // generate 10-microsecond pulse to TRIG pin
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
 
  // measure duration of pulse from ECHO pin
  duration_us = pulseIn(ECHO_PIN, HIGH);
  // calculate the distance
  distance_cm = 0.017 * duration_us;
  // ligt up led if distance under limit
  // print the value to Serial Monitor

servo.write(0);
  if(distance_cm <=30){
    for (pos = 0; pos <= 180; pos += 1) {
    servo.write(pos);
    delay(15);
    }
  delay(5000);
    for (pos = 180; pos >= 0; pos -= 1) {
    servo.write(pos);
    delay(15);
    }
    delay(10000);
  }
 // servo.Write(0);
}