void loop() {
  long duration, distance;
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);
  
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = (duration / 2) / 29.1; // Calculate distance in centimeters
  
  currentMillis = millis();
  elapsedTime = currentMillis - previousMillis;

  if (elapsedTime >= 0 && elapsedTime < 15000) { // 0-30 seconds
    delay(2000); // 2 seconds delay
  } else if (elapsedTime >= 15000 && elapsedTime < 30000) { // 30-60 seconds
    delay(1000); // 1 second delay
  } else if (elapsedTime >= 30000 && elapsedTime < 45000) { // 30-60 seconds
    delay(500); // 1 second delay
  } else if (elapsedTime >= 45000 && elapsedTime < 60000) { // 30-60 seconds
    delay(250); // 1 second delay
  } else if (elapsedTime >= 60000) { // 60 seconds and after
    delay(100); // 0.5 second delay
  }

  if (distance < 10) {
    activategreen(); // If object is close, activate green LED
    Serial.println("RECYCLABLE");
  } else if (distance >= 10 && distance < 20) {
    activatered(); // If object is at medium distance, activate red LED
    Serial.println("NON_RECYCLABLE");
  } else if (distance >= 20 && distance < 30) {
    activateblue(); // If object is at far distance, activate blue bin LED
    Serial.println("COMPOSTABLE");
  }
  
  delay(100); // Adjust delay as needed for data transmission
}