Çalışmayan kod

kodu d,worde de  yaıp dosya olarak yükledim bilginiz olsun.

//#include<Servo.h>

//Servo kalem;

//const byte sag_echo = 6;
//const byte sag_trig = 7;
//int sag_sure = 0;
//int sag_mesafe = 0;

//const byte sol_echo = 2;
//const byte sol_trig = 3;
//int sol_sure = 0;
//int sol_mesafe = 0;

const byte orta_echo = 13;
const byte orta_trig = 12;
int orta_sure = 0;
int orta_mesafe = 0;

#define SagMotorileri 4
#define SagMotorGeri 5
#define SolMotorileri 6
#define SolMotorGeri  7
#define B 11
#define EN1 9
#define EN2 3
int metal_pini = 8;         // variable for reading the pushbutton status
int metal = 0;

//int in=0;//yerdeki acıso
//int cik=90;//yukardaki acısı
void setup() {

  //kalem.attach(9);
  pinMode(SolMotorileri, OUTPUT);
  pinMode(SolMotorGeri, OUTPUT);
  pinMode(SagMotorileri, OUTPUT);
  pinMode(SagMotorGeri, OUTPUT);
pinMode(B, OUTPUT);
pinMode(EN1, OUTPUT);
pinMode(EN2, OUTPUT);


//pinMode(sag_echo , INPUT);
//  pinMode(sag_trig , OUTPUT);
//  
//pinMode(sol_echo , INPUT);
//  pinMode(sol_trig , OUTPUT);
  
pinMode(orta_echo , INPUT);
  pinMode(orta_trig , OUTPUT);
  
pinMode(metal_pini , INPUT);
  Serial.begin(9600);
//  kalem.write(cik); // ortada
 
}
void loop() {

  metal = digitalRead(metal_pini);
  
 bak();
  
  if (orta_mesafe < 20 )
  {
    digitalWrite(SolMotorileri, LOW);
    digitalWrite(SolMotorGeri, HIGH);
    digitalWrite(SagMotorileri, LOW);
    digitalWrite(SagMotorGeri, HIGH);
//     digitalWrite(EN1, HIGH);
//    digitalWrite(EN2, HIGH);
    delay (300);
    digitalWrite(SolMotorileri, HIGH);
    digitalWrite(SolMotorGeri, LOW);
    digitalWrite(SagMotorileri, LOW);
    digitalWrite(SagMotorGeri, HIGH);
//digitalWrite(EN1, HIGH);
//    digitalWrite(EN2, HIGH);

    
    delay (500);
  }

 else
 {
 metal = digitalRead(metal_pini);
 if (metal == LOW)
 {
  
//    digitalWrite(SolMotorileri, LOW);
//    digitalWrite(SolMotorGeri, LOW);
//    digitalWrite(SagMotorileri, LOW);
//    digitalWrite(SagMotorGeri, LOW);
    digitalWrite(B, HIGH);
    delay(300);

//    digitalWrite(SolMotorileri, LOW);
//    digitalWrite(SolMotorGeri, HIGH);
//    digitalWrite(SagMotorileri, LOW);
//    digitalWrite(SagMotorGeri, HIGH);
    digitalWrite(B,LOW);
    delay (300);
//    digitalWrite(SolMotorileri, LOW);
//    digitalWrite(SolMotorGeri, HIGH);
//    digitalWrite(SagMotorileri, HIGH);
//    digitalWrite(SagMotorGeri, LOW);
    digitalWrite(B, HIGH);
    delay (300);
 }
 
//    digitalWrite(SolMotorileri, HIGH);
//    digitalWrite(SolMotorGeri, LOW);
//    digitalWrite(SagMotorileri, HIGH);
//    digitalWrite(SagMotorGeri, LOW);
    digitalWrite(B,LOW);

}
}
void bak()

{
   
  digitalWrite(orta_trig , HIGH);
  delayMicroseconds(1000);
  digitalWrite(orta_trig , LOW);
 orta_sure = pulseIn(orta_echo , HIGH);
  orta_mesafe = (orta_sure / 2) / 28.5 ;
  delay (50);


  Serial.print ("  orta_mesafe ");
  Serial.println (orta_mesafe);
    
}