// Define ultrasonic sensor pins
const int trigPins[] = {2, 4, 7, 8};
const int echoPins[] = {3, 5, 6, 9};

// Define distance thresholds
const int frontThreshold = 20;  // in centimeters
const int rearThreshold = 20;   // in centimeters

void setup() {
  Serial.begin(9600);  // Initialize serial communication for debugging
}

void loop() {
  // Read distances from ultrasonic sensors
  int frontDistance = getDistance(trigPins[0], echoPins[0]);
  int rearDistance = getDistance(trigPins[1], echoPins[1]);

  // Check and display obstacle warnings
  checkObstacle(frontDistance, "Front");
  checkObstacle(rearDistance, "Rear");

  delay(100);  // Delay for stability and to avoid rapid readings
}

// Function to get distance from an ultrasonic sensor
int getDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  return pulseIn(echoPin, HIGH) * 0.034 / 2;  // Convert pulse duration to distance in centimeters
}

// Function to check and display obstacle warnings
void checkObstacle(int distance, String position) {
  Serial.print(position + " Distance: ");
  Serial.println(distance);

  if (position == "Front" && distance < frontThreshold) {
    Serial.println("Obstacle in front! Stop or take evasive action.");
    // Implement additional actions if needed (e.g., stop the vehicle)
  }

  if (position == "Rear" && distance < rearThreshold) {
    Serial.println("Obstacle in rear! Stop or take evasive action.");
    // Implement additional actions if needed (e.g., activate reverse gear)
  }
}