CRANE GAME

Step 2 Control a stepper with joy stick

Next we need to control a stepper motor the potentiometer on the joystick.

Hardware: 
Joystick -> Arduino (analog in) -> Arduino (digital out) -> Stepper driver -> stepper motor

I ran this using the EasyDriver from Sparkfun by www.SchmalzHaus.com/EasyDriver
It is well labeled and can run a medium sized stepper motor from the USB power supply. (in this example I am using a NEM17 from Keling Technology).

The screw sheild is by ZachHoeken: http://reprap.org/bin/view/Main/Arduino_Breakout_1_4

Code to control stepper motor from joystick potentiometer

///////////////////////   Arduino ///////////////////////

//******* POT to control a stepper speed and direction ******//

//declare pins
int potPin = 1;
int Step_X = 13;
int Dir_X = 12;
int Enable_X = 8;

//declare values
int Speed_X = 0;       //step speed (delay between steps) 
int val= 0;
int j = 0;

void setup() {
  pinMode(Step_X, OUTPUT);
  pinMode(Dir_X, OUTPUT);
  pinMode(Enable_X, OUTPUT);

  //Serial.begin(9600); // note that serial comm can be used to debug
                        // but it will slow down the code and slow down the stepper motor alot 
                       //(and be confusing to me)
}

void loop() {

  val = analogRead(potPin);    // read the value from the sensor

  j = val - 517;  // 517 is center positions - how far from center?
  j = abs(j);      //absolute value
  Speed_X = 70000/j;  //This math inverts the value and scales as needed 
                       //(value found through trial and error)
                      // The delay between steps will determine the speed of the motor
                       // So, delay up = speed down

  if (val >= 520){
    digitalWrite(Enable_X,LOW); // enable
    digitalWrite(Dir_X, HIGH);  // Set direction
    digitalWrite(Step_X,HIGH);
    delayMicroseconds(2);
    digitalWrite(Step_X,LOW);
    delayMicroseconds(Speed_X);

  }
  if (val <= 510) {
    digitalWrite(Enable_X,LOW);// enable
    digitalWrite(Dir_X, LOW);  // Other direction
    digitalWrite(Step_X,HIGH);
    delayMicroseconds(2);
    digitalWrite(Step_X,LOW);
    delayMicroseconds(Speed_X);
  }

  if (val <=520 && val >= 510) { 
    digitalWrite(Enable_X,HIGH);  // disable the stepper motor if the joystic is in the center
  }
}

 
 

Comments

[yel-shourafa]

sorry i forgot to say : As you know the two POTs will be the joystick ;)

[yel-shourafa]

yeah me too i have to control two steppers which have 20 n.m torque '' big motors '' and i have the stepper drivers.
the motors are installed in a 4 wheeler cart.
i made a code to control the cart forward and backward using the motors+drivers+Arduino uno+potentiometer
and then i made another code without the potentiometer
using 3 Arduinos ( 1 master and two slaves) each slave is connected to a motor
the code is to apply speed to one of the motors for ex 10 rpm and the other motor
5 rpm .. just to make the cart turns left or right ...
THE QUESTION NOW WHAT IS THE CODE FOR THE STEERING USING THE POTENTIOMETER ??
there will be 2 POTs one for steering and the other for moving.
PLEASE HELP !!!

[juande3003]

Hello,

I need your help, I'm doing a project similar to yours, a pan tilt head and I need to control two stepper motors with a joystick.
Can you help me with the code? How would two stepper motors?

I'd appreciate if you can send photos or a wiring diagram.

Thank you very much.

[marc.cryan]

Do you have to use stepper motors?

There are alot of examples of pan-and-tilt using hobby servo motors.

Here is an example of pan/tilt using servos and joystick: http://www.practicalarduino.com/news/id/411
the code is here: https://github.com/practicalarduino/PanTiltControl/blob/master/PanTiltControl.pde

spark fun has parts: http://www.sparkfun.com/products/10335

[juande3003]

Yes, I need to do it with stepper motors, is difficult to code for two engines?

[marc.cryan]

Yeah -- hobby servos have built in feedback, you just need to tell them the angle and they go. If you use stepper motors you need a circuit to drive the motors and some sensors to get feedback on the position of the motors. On the other hand, stepper motors are usually sturdy with more power; so it might be worth it.

Good luck!

[juande3003]

Thanks for responding,
I like to use stepper motors because they have strength and are accurate. Project where you use your joystick, you use a stepper motor, could you help me with the code to use 2 stepper motors?
I know nothing about programming, so I ask for help.

Thanks for everything,

Greetings.