Hands-free Garbage Can

Original code for 4-pin ultrasonic sensor here. My code below adds the servo functions:

/*Auto Garbage Can Lid Openering Thing 
with HC-SR04 Sensor

 */
const int servo = 11;
const int ledpin = 13;
const int trigPin = 2;
const int echoPin = 4;
int potpin = A0;

int rotations = 0;

const int clockwise = 1700;
const int counterclockwise = 1300;

void setup() {
  // initialize serial communication:
  Serial.begin(9600);
    pinMode(ledpin, OUTPUT);
  digitalWrite(ledpin,LOW);
}

void loop()
{

  long duration, inches, cm;
  rotations = analogRead(potpin);
  rotations = map (rotations,0, 1023, 10, 400);

  // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
  pinMode(trigPin, OUTPUT);
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Read the signal from the sensor: a HIGH pulse whose
  // duration is the time (in microseconds) from the sending
  // of the ping to the reception of its echo off of an object.
  pinMode(echoPin, INPUT);
  duration = pulseIn(echoPin, HIGH);

  // convert the time into a distance
  inches = microsecondsToInches(duration);
  cm = microsecondsToCentimeters(duration);
  
  //Serial.print(inches); Serial.print("in, ");
  //Serial.print(cm); Serial.print("cm");  Serial.println();
  Serial.print(rotations); Serial.println();
  
   if (inches < 5) {
    digitalWrite(ledpin,HIGH);
     for(int i=0; i<rotations; i++)
    {
    digitalWrite(servo,HIGH);
    delayMicroseconds(clockwise); 
    digitalWrite(servo,LOW);
    delay(18.5); // 18.5ms 
    //delay(50); 
    }
  delay(3000);
     for(int i=0; i<rotations; i++)
    {
    digitalWrite(servo,HIGH);
    delayMicroseconds(counterclockwise); 
    digitalWrite(servo,LOW);
    delay(18.5); // 18.5ms 

}}

 if (inches > 5) {   
     digitalWrite(ledpin,LOW);}
  
  delay(100);
}

long microsecondsToInches(long microseconds)
{
  // According to Parallax's datasheet for the PING))), there are
  // 73.746 microseconds per inch (i.e. sound travels at 1130 feet per
  // second).  This gives the distance travelled by the ping, outbound
  // and return, so we divide by 2 to get the distance of the obstacle.
  // See: http://www.parallax.com/dl/docs/prod/acc/28015-PING-v1.3.pdf
  return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds)
{
  // The speed of sound is 340 m/s or 29 microseconds per centimeter.
  // The ping travels out and back, so to find the distance of the
  // object we take half of the distance travelled.
  return microseconds / 29 / 2;
}