Robot joystick nRF24L01

Projects Programming
1

Hello !!!
I have a robot ,a joystick and 2 nRF24L01 modules in 2 arduinos (mega and uno) and I have a problem with joystick.
When push the joystick forward or left all is ok (4 wheels move),but when I push it backward or right only one wheel do not move (I do not know why)

Reciever code (arduino mega):

#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>

const uint64_t pipe = 0xE8E8F0F0E1LL;
RF24 radio(7, 8);

const int IN_1_back_left = 6;
const int IN_2_back_left = 9;
const int PWM_back_left = 10;
const int IN_1_back_right = 48;
const int IN_2_back_right = 46;
const int PWM_back_right = 11;
const int IN_1_front_left = 2;
const int IN_2_front_left = 3;
const int PWM_front_left = 13;
const int IN_1_front_right = 42;
const int IN_2_front_right = 44;
const int PWM_front_right = 12;
int forwardSpeed = 0;         //define the forward speed of motors
int backwardSpeed = 0;        //define the backward speed of motors
int rightSpeed = 0;           //define the right turn only speed of motors
int leftSpeed = 0;            //define the left turn only speed of motors
int joystick[2];              // 2 element array holding Joystick readings
int flagStop = 0;


void setup()
{
  radio.begin();
  radio.openReadingPipe(1, pipe);
  radio.startListening();
  pinMode(PWM_back_left, OUTPUT);
  pinMode(PWM_back_right, OUTPUT);
  pinMode(PWM_front_left, OUTPUT);
  pinMode(PWM_front_right, OUTPUT);

  pinMode(IN_1_back_left, OUTPUT);
  pinMode(IN_2_back_left, OUTPUT);
  pinMode(IN_1_back_right, OUTPUT);
  pinMode(IN_2_back_right, OUTPUT);

  pinMode(IN_1_front_left, OUTPUT);
  pinMode(IN_2_front_left, OUTPUT);
  pinMode(IN_1_front_right, OUTPUT);
  pinMode(IN_2_front_right, OUTPUT);

  analogWrite(PWM_back_left, 0);
  analogWrite(PWM_back_right, 0);
  analogWrite(PWM_front_left, 0);
  analogWrite(PWM_front_right, 0);
}


void FORWARD()
{
  digitalWrite(IN_1_back_left , HIGH);      //forward
  digitalWrite(IN_2_back_left , LOW);
  digitalWrite(IN_1_back_right , HIGH);
  digitalWrite(IN_2_back_right , LOW);

  digitalWrite(IN_1_front_left , HIGH);
  digitalWrite(IN_2_front_left , LOW);
  digitalWrite(IN_1_front_right , HIGH);
  digitalWrite(IN_2_front_right , LOW);
}


void BACKWARD()
{
  digitalWrite(IN_1_back_left , LOW);       //backward
  digitalWrite(IN_2_back_left , HIGH);
  digitalWrite(IN_1_back_right , LOW);
  digitalWrite(IN_2_back_right , HIGH);

  digitalWrite(IN_1_front_left , LOW);
  digitalWrite(IN_2_front_left , HIGH);
  digitalWrite(IN_1_front_right , LOW);
  digitalWrite(IN_2_front_right , HIGH);
}


void STOP()
{
  digitalWrite(IN_1_back_left , LOW);       //stop
  digitalWrite(IN_2_back_left , LOW);
  digitalWrite(IN_1_back_right , LOW);
  digitalWrite(IN_2_back_right , LOW);

  digitalWrite(IN_1_front_left , LOW);
  digitalWrite(IN_2_front_left , LOW);
  digitalWrite(IN_1_front_right , LOW);
  digitalWrite(IN_2_front_right , LOW);
}


void RIGHT()
{
  digitalWrite(IN_1_back_left , HIGH);      //right
  digitalWrite(IN_2_back_left , LOW);
  digitalWrite(IN_1_back_right , LOW);
  digitalWrite(IN_2_back_right , HIGH);

  digitalWrite(IN_1_front_left , HIGH);
  digitalWrite(IN_2_front_left , LOW);
  digitalWrite(IN_1_front_right , LOW);
  digitalWrite(IN_2_front_right , HIGH);
}


void LEFT()
{
  digitalWrite(IN_1_back_left , LOW);      //left
  digitalWrite(IN_2_back_left , HIGH);
  digitalWrite(IN_1_back_right , HIGH);
  digitalWrite(IN_2_back_right , LOW);

  digitalWrite(IN_1_front_left , LOW);
  digitalWrite(IN_2_front_left , HIGH);
  digitalWrite(IN_1_front_right , HIGH);
  digitalWrite(IN_2_front_right , LOW);
}



void forward()
{
  forwardSpeed = map(joystick[1], 510, 1023, 0, 255);
  FORWARD();
  analogWrite(PWM_back_left, forwardSpeed);
  analogWrite(PWM_back_right, forwardSpeed);
  analogWrite(PWM_front_left, forwardSpeed);
  analogWrite(PWM_front_right, forwardSpeed);
}
void backward()
{
  backwardSpeed = map(joystick[1], 506, 0, 0, 255);
  BACKWARD();
  analogWrite(PWM_back_left, backwardSpeed);
  analogWrite(PWM_back_right, backwardSpeed);
  analogWrite(PWM_front_left, backwardSpeed);
  analogWrite(PWM_front_right, backwardSpeed);
}

void left()
{
  leftSpeed = map(joystick[0], 517, 1023, 0, 255);
  LEFT();
  analogWrite(PWM_back_left, leftSpeed);
  analogWrite(PWM_back_right, leftSpeed);
  analogWrite(PWM_front_left, leftSpeed);
  analogWrite(PWM_front_right, leftSpeed);
}
void right()
{
  rightSpeed = map(joystick[0], 517, 0, 0, 255);
  RIGHT();
  analogWrite(PWM_back_left, rightSpeed);
  analogWrite(PWM_back_right, rightSpeed);
  analogWrite(PWM_front_left, rightSpeed);
  analogWrite(PWM_front_right, rightSpeed);
}
void forandright()
{
  forwardSpeed = map(joystick[1], 513, 1023, 0, 255);
  FORWARD();
  analogWrite(PWM_back_left, forwardSpeed);
  analogWrite(PWM_back_right, forwardSpeed / 2);
  analogWrite(PWM_front_left, forwardSpeed);
  analogWrite(PWM_front_right, forwardSpeed / 2);
}

void forandleft()
{
  forwardSpeed = map(joystick[1], 513, 1023, 0, 255);
  FORWARD();
  analogWrite(PWM_back_left, forwardSpeed / 2);
  analogWrite(PWM_back_right, forwardSpeed);
  analogWrite(PWM_front_left, forwardSpeed / 2);
  analogWrite(PWM_front_right, forwardSpeed);
}

void backandright()
{
  backwardSpeed = map(joystick[1], 517, 0, 255, 0);
  BACKWARD();
  analogWrite(PWM_back_left, backwardSpeed);
  analogWrite(PWM_back_right, backwardSpeed / 2);
  analogWrite(PWM_front_left, backwardSpeed);
  analogWrite(PWM_front_right, backwardSpeed / 2);
}

void backandleft()
{
  backwardSpeed = map(joystick[1], 517, 0, 0, 255);
  BACKWARD();
  analogWrite(PWM_back_left, backwardSpeed / 2);
  analogWrite(PWM_back_right, backwardSpeed);
  analogWrite(PWM_front_left, backwardSpeed / 2);
  analogWrite(PWM_front_right, backwardSpeed);
}



void loop()
{
  if (radio.available())
  {
    radio.read(joystick, sizeof(joystick));
    flagStop = 0;
  }

  if (joystick[1] > 502 && joystick[1] < 510 && joystick[0] >= 509 && joystick[0] <= 510)
  {
    STOP();
    flagStop = 1;
  }

  else
  {
    flagStop = 0;
  }

  if (flagStop == 0)
  {
    if (joystick[0] <= 508 && joystick[1] >= 516)
    {
      forandright();
    }

    else if (joystick[0] >= 513 && joystick[1] >= 516)
    {
      forandleft();
    }

    else if (joystick[0] <= 508 && joystick[1] <= 502)
    {
      backandright();
    }
    else if (joystick[0] >= 513 && joystick[1] <= 502)
    {
      backandleft();
    }

    else if (joystick[1] <= 505 && joystick[0] >= 509 && joystick[0] <= 513)
    {
      backward();
    }
    else if (joystick[1] >= 510 && joystick[0] <= 513 && joystick[0] >= 509)
    {
      forward();
    }

    else if (joystick[0] >= 516)
    {
      left();
    }

    else if (joystick[0] <= 508)
    {
      right();
    }
  }
  else
  {
    STOP();
    flagStop = 1;
  }
}

Transmitter code (arduino uno):

#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>

#define JOYSTICK_X A0
#define JOYSTICK_Y A1

const uint64_t pipe = 0xE8E8F0F0E1LL;
RF24 radio(7, 8);
int joystick[2];           // 2 element array holding Joystick readings

void setup()
{
  radio.begin();
  radio.openWritingPipe(pipe);
}


void loop()
{
  joystick[0] = analogRead(JOYSTICK_X);
  joystick[1] = analogRead(JOYSTICK_Y);
  radio.write(joystick, sizeof(joystick));
}
2

Have you directly tested that it moves as desired in all modes without the RF link?

What do your Serial debug prints show?

3

No but this is not the problem because all wheels are moving when I push forward or left the joystick.Only in right and backward 3/4 wheels are moving and I dont know why this is happening..

5

On your receiver, comment out all the code in the loop that makes the motors move.
Put in code that writes the 2 joystick values to the serial monitor.
Run this and confirm that the values being printed on the serial monitor match what you expect to receive for various joystick positions.

Troubleshooting will be much more direct if you first get confidence that the serial communication is working as expected.

6

vinceherman:
On your receiver, comment out all the code in the loop that makes the motors move.

Yes, divide and conquer. My suggestion in Reply #1 was to check out the drive part first (but this way is just as valid). That was rejected by @arduiNICK because he apparently knows where the problem is.

My hint about Serial debug prints was also ignored.

7

Ok thanks .I will do it.