L293D shield not providing enough power

Other Hardware Motors, Mechanics, Power and CNC
1

So I got an L293D shield attached to 2 DC motors, and the problem is that only one of those can move without any 'help'. When I try to move both motors, I need to manually push the wheel connected to the DC motor to make them go. The Arduino board(UNO btw) is currently connected to my laptop. How do I fix this problem?

#include <SoftwareSerial.h>
#include <AFMotor.h>

AF_DCMotor motor1(1);
AF_DCMotor motor2(2);
SoftwareSerial Bluetooth(2,4);


char c=' ';
char cb=' ';
int k=0;

void setup() {
  Serial.begin(9600);
  Serial.println("ready");
  Bluetooth.begin(38400);
  motor1.setSpeed(255);
  motor1.run(RELEASE);
  motor2.setSpeed(255);
  motor2.run(RELEASE);
}
char inputs[5] = {'N','N','N','N','N'};  
int move=0;
int dir=0;
int lr=0;

void loop() {


  if(Bluetooth.available()) {
    cb=c;
    c=Bluetooth.read();
    Serial.write(c);
    if(cb==c) {
      k++;
      if(k>=10 && inputs[4]!=c) {
        for(int j=0; j<4; j++) {
          inputs[j]=inputs[j+1];
        }
        inputs[4]=c;
      }
    }
    else {
      k=0;
    }
    if(inputs[4]=='N' && inputs[3]=='T' && inputs[2]=='O' && inputs[1]=='N') {
      Serial.write("AAAAAAA");
      if(move==0) {
        motor1.run(FORWARD);
        motor2.run(FORWARD);
        move=1;
        dir=0;
      }
      else if(move==1) {
        motor1.run(RELEASE);
        motor2.run(RELEASE);
        move=0;
      }
      for(int i=0; i<5; i++) {
        inputs[i]='N';
      }
    }
    if(inputs[4]=='N' && inputs[3]=='O' && inputs[2]=='N') {
      if(dir==1 && move==1){
        motor1.run(FORWARD);
        motor2.run(FORWARD);
        dir=0;
      }
      else if(dir==0 && move==1) {
        motor1.run(BACKWARD);
        motor2.run(BACKWARD);
        dir=1;
      }
      for(int i=0; i<5; i++) {
        inputs[i]='N';
      }
    }
    if(inputs[4]=='O' && inputs[3]=='T'&& inputs[2]=='O') {
      if(lr==0 || lr==1) {
        motor1.setSpeed(100);
        lr=-1;
      }
      else if(lr==-1) {
        motor1.setSpeed(200);
        lr=0;
      }
      for(int i=0; i<5; i++) {
        inputs[i]='N';
      }
    }
    if(inputs[4]=='N' && inputs[3]=='T' && inputs[2]=='N') {
      if(lr==-1 || lr==0) {
        motor2.setSpeed(100);
        lr=1;
      }
      else if(lr=1) {
        motor2.setSpeed(200);
        lr=0;
      }
      for(int i=0; i<5; i++) {
        inputs[i]='N';
      }
    }

    for(int i=0; i<5; i++) {
      Serial.write(inputs[i]);
    }
    Serial.write(" ");
    Serial.print(move);
    Serial.write(" ");
    Serial.print(dir);
    Serial.write(" ");
    Serial.print(lr);
    Serial.write("\n");
  }

}

here's the code

and these are the wheels and the motors that I'm using:

2

Where is the power to the motors coming from ?

3

I have the Arduino UNO connected to my laptop via USB cable and mounted an L293D motor shield on top of it. There are no other power sources.

4

You cannot sensibly power those motors from USB because of the current required. They need an external power supply

5

Another issue: USB is 5V.
With L293D you loose 2V..
Only 3V left...
Try 9V for the motors. L293D has 2 power connections. One for 5V (for the inside controller) and another to feed the motors (can take higher voltage).
5V can be taken from arduino.

6

But not from a PP3 battery

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7

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