#include <Servo.h>

Servo gate;

#define trig_pin 12
#define echo_pin 11

float duration;
float distance;


void setup() {
  gate.attach(5);
  pinMode(trig_pin, OUTPUT);
  pinMode(echo_pin, INPUT);
  Serial.begin(9600);
}

void loop() {
  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;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println("  Cm");

  if (distance>50 && distance <150)
  {
    gate.write(90);
  }
  else
  {
    gate.write(0);
  }
  delay(1000);

}