Arduino senzors HC SR04

Other Hardware Sensors
1

Hello.
Im have problem with code, I'm just a beginner in the Scripting Arduino cods, If someone explain or edit this prescription I'd be grateful. Thank you.
First I made my first RC car, and it went well, but I bought HC SR04, and I wish that when we robot encounters an obstacle and to stop when the robot is at 10 or 15 cm close to some barriers to stop and waiting for me to do something, thank you. I know there is somewhere on this forum, but I would not want anyone to explain to my code. Thank you

#include <NewPing.h> 

const int motor1Pin1 = 5;
const int motor1Pin2 = 6;
const int motor2Pin1 = 9;
const int motor2Pin2 = 10;
byte serialA;

#define TRIGGER_PIN  7
#define ECHO_PIN     8
#define MAX_DISTANCE 200
int distance = 100;
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE);

void setup() {
  
 Serial.begin(9600);
    pinMode(motor1Pin1, OUTPUT);
    pinMode(motor1Pin2, OUTPUT);
    pinMode(motor2Pin1, OUTPUT);
    pinMode(motor2Pin2, OUTPUT);

    Serial.begin(115200);


}

void loop() {

 delay(50);
 Serial.print("Ping: ");
 Serial.print(sonar.ping_cm());
 Serial.println("cm");

if (Serial.available() > 0) {serialA = Serial.read();Serial.println(serialA);}

   switch (serialA) {
    // forward
   case 'F':
        digitalWrite(motor1Pin1, HIGH);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        break;
        
        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        }
        
         // left
    case 'L':
        digitalWrite(motor1Pin1, HIGH);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        }
        
    // right
    case 'R':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        break;
        
        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        } 
       
    // forward left
    case 'G':
        digitalWrite(motor1Pin1, HIGH); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        } 
    

    // forward right
    case 'I':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        }
    

    // backward left
    case 'H':
        digitalWrite(motor1Pin1, HIGH); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        } 
    
    // backward right
    case 'J':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        }
    
    // backward
    case 'B':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH);
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        break;

        if (distance <= 15){
        digitalWrite(motor1Pin1, LOW);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        break;    
        }
    
     // Stop
     case 'S':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW); }
    }
2

your distance test is not where they should be..
notice your "break;" just in front of the tests -> tests never run -> remove them from where they are now.

Add your test after (or before) the switch-statement.
Think of HOW you can move back from the faulty posision - avoid beeing stuck

3 
const int motor1Pin1 = 5;
const int motor1Pin2 = 6;
const int enablem1Pin3 = 11;
const int motor2Pin1 = 10;
const int motor2Pin2 = 9;
const int enablem2Pin3 = 3;

byte serialA;



void setup() {
  
 Serial.begin(9600);

    pinMode(motor1Pin1, OUTPUT);
    pinMode(motor1Pin2, OUTPUT);
    pinMode(enablem1Pin3, OUTPUT);
    pinMode(motor2Pin1, OUTPUT);
    pinMode(motor2Pin2, OUTPUT);
    pinMode(enablem2Pin3, OUTPUT);

}

void loop() {

if (Serial.available() > 0) {serialA = Serial.read();Serial.println(serialA);}

   switch (serialA) {
    // naprijed
   case 'F':
        digitalWrite(motor1Pin1, HIGH);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
        
         // lijevo
    case 'L':
        digitalWrite(motor1Pin1, HIGH);
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, LOW);
        break; 
        
    // desno
    case 'R':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        digitalWrite(enablem1Pin3, LOW);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
       
    // naprijed lijevo
    case 'G':
        digitalWrite(motor1Pin1, HIGH); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
    

    // naprijed desno
    case 'I':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
    

    // u nazad lijevo
    case 'H':
        digitalWrite(motor1Pin1, HIGH); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
    
    // u nazad desno
    case 'J':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, HIGH);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
    
    // unazad
    case 'B':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, HIGH);
        digitalWrite(motor2Pin1, HIGH);
        digitalWrite(motor2Pin2, LOW);
        digitalWrite(enablem1Pin3, HIGH);
        digitalWrite(enablem2Pin3, HIGH);
        break; 
    
     // stani
     case 'S':
        digitalWrite(motor1Pin1, LOW); 
        digitalWrite(motor1Pin2, LOW); 
        digitalWrite(motor2Pin1, LOW);
        digitalWrite(motor2Pin2, LOW);
        digitalWrite(enablem1Pin3, LOW);
        digitalWrite(enablem2Pin3, LOW); }
    }