Motor not moving backwards using L293D Motor Driver sheild

Other Hardware Motors, Mechanics, Power and CNC
1

Hello everyone,
i have been trying to make an obstacle avoiding robot but the motor driver does not take commands to rotate backwards.
btw im using 2 3.7v 5000mah 18650 li-on batteries.(is it too much for the arduino?)
its taking the delay time before the moving backwards code but it still not sending command to turn the motors backwards

THANK YOU IN ADVANCE

#include <AFMotor.h>  
#include <NewPing.h>
#include <Servo.h> 

#define TRIG_PIN A3
#define ECHO_PIN A5
#define MAX_DISTANCE 500
#define MAX_SPEED 150 // sets speed of DC  motors
#define MAX_SPEED_OFFSET 5

NewPing sonar(TRIG_PIN, ECHO_PIN, MAX_DISTANCE); 

AF_DCMotor motor1(1, MOTOR12_1KHZ); 
AF_DCMotor motor2(2, MOTOR12_1KHZ);
AF_DCMotor motor3(3, MOTOR34_1KHZ);
AF_DCMotor motor4(4, MOTOR34_1KHZ);
Servo myservo;   

boolean goesForward=false;
int distance = 100;
int speedSet = 0;

void setup() {

  myservo.attach(10);  
  myservo.write(115); 
  delay(2000);
  distance = readPing();
  delay(100);
  distance = readPing();
  delay(100);
  distance = readPing();
  delay(100);
  distance = readPing();
  delay(100);
}

void loop() {
 int distanceR = 0;
 int distanceL = 0;
 delay(40);
 
 if(distance<=15)
 {
  moveStop();
  delay(100);
  moveBackward();
  delay(300);
  moveStop();
  delay(200);
  distanceR = lookRight();
  delay(200);
  distanceL = lookLeft();
  delay(200);

  if(distanceR>=distanceL)
  {
    turnRight();
    moveStop();
  }
  else
  {
    turnLeft();
    moveStop();
  }
 }
 else
 {
  moveForward();
 }
 distance = readPing();
}

int lookRight()
{
    myservo.write(50); 
    delay(500);
    int distance = readPing();
    delay(100);
    myservo.write(115); 
    return distance;
}

int lookLeft()
{
    myservo.write(170); 
    delay(500);
    int distance = readPing();
    delay(100);
    myservo.write(115); 
    return distance;
    delay(100);
}

int readPing() { 
  delay(70);
  int cm = sonar.ping_cm();
  if(cm==0)
  {
    cm = 250;
  }
  return cm;
}

void moveStop() {
  motor1.run(RELEASE); 
  motor2.run(RELEASE);
  motor3.run(RELEASE);
  motor4.run(RELEASE);
  } 
  
void moveForward() {

 if(!goesForward)
  {
    goesForward=true;
    motor1.run(FORWARD);      
    motor2.run(FORWARD);
    motor3.run(FORWARD); 
    motor4.run(FORWARD);     
   for (speedSet = 0; speedSet < MAX_SPEED; speedSet +=2) // slowly bring the speed up to avoid loading down the batteries too quickly
   {
    motor1.setSpeed(speedSet);
    motor2.setSpeed(speedSet);
    motor3.setSpeed(speedSet);
    motor4.setSpeed(speedSet);
    delay(5);
   }
  }
}

void moveBackward() {
    goesForward=false;
    motor1.run(BACKWARD);      
    motor2.run(BACKWARD);
    motor3.run(BACKWARD);
    motor4.run(BACKWARD);  
  for (speedSet = 0; speedSet < MAX_SPEED; speedSet +=2) // slowly bring the speed up to avoid loading down the batteries too quickly
  {
    motor1.setSpeed(speedSet);
    motor2.setSpeed(speedSet);
    motor3.setSpeed(speedSet);
    motor4.setSpeed(speedSet);
    delay(5);
  }
}  

void turnRight() {
  motor1.run(FORWARD);
  motor2.run(FORWARD);
  motor3.run(BACKWARD);
  motor4.run(BACKWARD);     
  delay(500);
  motor1.run(FORWARD);      
  motor2.run(FORWARD);
  motor3.run(FORWARD);
  motor4.run(FORWARD);      
} 
 
void turnLeft() {
  motor1.run(BACKWARD);     
  motor2.run(BACKWARD);  
  motor3.run(FORWARD);
  motor4.run(FORWARD);   
  delay(500);
  motor1.run(FORWARD);     
  motor2.run(FORWARD);
  motor3.run(FORWARD);
  motor4.run(FORWARD);
}

this is the code

2

Always show us a good schematic of your proposed circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.

3

You don't need to specify the motor frequency. The default is 1kHz.
You're also only moving backwards for 300 ms. You don't have a return in your "moveBackwards" function. So, I don't know for sure that it will wait for that function to return before continuing with the rest of the code. So that might be all it wait for before continuing on.

4

I hope those motors work on 3.7V - 2.8V (drop in L298) = 0.9V. Since you are running two motors with the batteries in parallel. At this point if that is not how there connected post a real annotated schematic as you have wired it, not a useless frizzy picture. Be sure the schematic has all power, grounds and power sources shown. My eyes are not very good and I cannot see what you have so post links to Technical information on each of the hardware items involved.

5

well i added it but the thing is it sense the distance waits and does everything else other than the "moveBackward" function could it be a misfunction in the motor driver cuz before the arduino loads up leftfront wheel starts moving backwards for some reason.

6

You don't mention what motor driver you are using.

7

image

this one L293D

8

this one L293D

9

How about posting a link to it and your schematic!

10

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