#include <Servo.h>

#define TRIG_PIN_1 2
#define ECHO_PIN_1 3
#define SERVO_PIN_1 9

#define TRIG_PIN_2 4
#define ECHO_PIN_2 5
#define SERVO_PIN_2 10

#define TRIG_PIN_3 6
#define ECHO_PIN_3 7
#define SERVO_PIN_3 11

#define TRIG_PIN_4 8
#define ECHO_PIN_4 12
#define SERVO_PIN_4 13

Servo servo1;
Servo servo2;
Servo servo3;
Servo servo4;

void setup() {
  pinMode(TRIG_PIN_1, OUTPUT);
  pinMode(ECHO_PIN_1, INPUT);
  servo1.attach(SERVO_PIN_1);
  
  pinMode(TRIG_PIN_2, OUTPUT);
  pinMode(ECHO_PIN_2, INPUT);
  servo2.attach(SERVO_PIN_2);
  
  pinMode(TRIG_PIN_3, OUTPUT);
  pinMode(ECHO_PIN_3, INPUT);
  servo3.attach(SERVO_PIN_3);
  
  pinMode(TRIG_PIN_4, OUTPUT);
  pinMode(ECHO_PIN_4, INPUT);
  servo4.attach(SERVO_PIN_4);
}

void loop() {
  long duration1, distance1;
  long duration2, distance2;
  long duration3, distance3;
  long duration4, distance4;
  
  // Measure distance from sensor 1
  digitalWrite(TRIG_PIN_1, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_1, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_1, LOW);
  duration1 = pulseIn(ECHO_PIN_1, HIGH);
  distance1 = duration1 * 0.034 / 2;

  // Measure distance from sensor 2
  digitalWrite(TRIG_PIN_2, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_2, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_2, LOW);
  duration2 = pulseIn(ECHO_PIN_2, HIGH);
  distance2 = duration2 * 0.034 / 2;

  // Measure distance from sensor 3
  digitalWrite(TRIG_PIN_3, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_3, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_3, LOW);
  duration3 = pulseIn(ECHO_PIN_3, HIGH);
  distance3 = duration3 * 0.034 / 2;

  // Measure distance from sensor 4
  digitalWrite(TRIG_PIN_4, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_4, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_4, LOW);
  duration4 = pulseIn(ECHO_PIN_4, HIGH);
  distance4 = duration4 * 0.034 / 2;

  // Check and respond to distance for each sensor
  if (distance1 < 20) {
    servo1.write(90);
  } else {
    servo1.write(0);
  }
  
  if (distance2 < 20) {
    servo2.write(90);
  } else {
    servo2.write(0);
  }
  
  if (distance3 < 20) {
    servo3.write(90);
  } else {
    servo3.write(0);
  }
  
  if (distance4 < 20) {
    servo4.write(90);
  } else {
    servo4.write(0);
  }
  
  delay(500); // Adjust delay as needed
}