const int trigPins0 = 10;
const int echoPins0 = A3;
const int trigPins1= 11;
const int echoPins1= A1;
const int trigPins2= 12;
const int echoPins2= A2;
const int trigPins3= 13;
const int echoPins3= A0;

const int stepPins0 = 2;
const int dirPins0 = 6;
const int stepPins1 = 3;
const int dirPins1 =  7;
const int stepPins2 = 4;
const int dirPins2 =  8;
const int stepPins3 = 5;
const int dirPins3 =  9;
#define warning 30

void setup() 
{
  Serial.begin(9600);
 
    pinMode(trigPins0, OUTPUT);
    pinMode(echoPins0, INPUT);
        pinMode(trigPins1, OUTPUT);
    pinMode(echoPins1, INPUT);
        pinMode(trigPins2, OUTPUT);
    pinMode(echoPins2, INPUT);
        pinMode(trigPins3, OUTPUT);
    pinMode(echoPins3, INPUT);

 pinMode(stepPins0, OUTPUT);
    pinMode(dirPins0, OUTPUT);
     pinMode(stepPins1, OUTPUT);
    pinMode(dirPins1, OUTPUT);
     pinMode(stepPins2, OUTPUT);
    pinMode(dirPins2, OUTPUT);
     pinMode(stepPins3, OUTPUT);
    pinMode(dirPins3, OUTPUT);

  
}


long readDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  long duration = pulseIn(echoPin, HIGH);
  long distance = duration * 0.034 / 2;
 return distance;


}
void loop() 
{
   long distanceLeft = readDistance(trigPins2, echoPins2);
  long distanceRight = readDistance(trigPins0, echoPins0);
  long distanceFront = readDistance(trigPins1, echoPins1);
  long distanceBack = readDistance(trigPins3, echoPins3);

 
if (distanceLeft <= warning) {
    Serial.println("Warning: Object too close on the LEFT side!");
    // Activate warning signal (LED/Buzzer)
  }
  if (distanceRight <= warning) {
    Serial.println("Warning: Object too close on the RIGHT side!");
    // Activate warning signal (LED/Buzzer)
  }
  if (distanceFront <= warning) {
    Serial.println("Warning: Object too close at the FRONT!");
    // Activate warning signal (LED/Buzzer)
  }
  if (distanceBack <= warning) {
    Serial.println("Warning: Object too close at the BACK!");
    // Activate warning signal (LED/Buzzer)
  }
   for (int x = 0; x < 200; x++) 
  { 
   digitalWrite(stepPins0, HIGH);
    digitalWrite(stepPins1, HIGH);
     digitalWrite(stepPins2, HIGH);
      digitalWrite(stepPins3, HIGH);
    delayMicroseconds(800); 
   digitalWrite(stepPins0, LOW);
    digitalWrite(stepPins1, LOW);
     digitalWrite(stepPins2, LOW);
      digitalWrite(stepPins3, LOW);
    delayMicroseconds(800); 
  } 
  

  delay(100); 
}