Manejar un motor DC con Arduino sin integrados

BASADO EN LA LIBRERÍA STEPPER.H DE ARDUINO

Para utilizar un motor dc con polaridad en un arduino sin utilizar ningún chip o integrado, se podría realizar de la siguiente forma:
(descarga estos archivos al final de esta entrada del blog)

1. Crear una carperta en las librerias que se llame MotorDC o como desee.

2. Buscar en las librerías del arduino dentro de la carpeta Stepper y copiarlos en MotorDC (básicamente son dos Stepper.h y Stepper.cpp)


3. Cambiar de nombre a los archivos por MotorDC.h y MotorDC.cpp respectivamente.

4. Abrir el archivo MotorDC.cpp y eliminar las siguientes líneas.

case 1: /* 11 */
digitalWrite(motor_pin_1, HIGH);
digitalWrite(motor_pin_2, HIGH);
break;
case 2: /* 10 */
digitalWrite(motor_pin_1, HIGH);
digitalWrite(motor_pin_2, LOW);
break;
case 3: /* 00 */
digitalWrite(motor_pin_1, LOW);
digitalWrite(motor_pin_2, LOW);
break;

y luego


digitalWrite(motor_pin_3, HIGH);
digitalWrite(motor_pin_4, LOW);
break;
case 1: // 0110
digitalWrite(motor_pin_1, LOW);
digitalWrite(motor_pin_2, HIGH);
digitalWrite(motor_pin_3, HIGH);
digitalWrite(motor_pin_4, LOW);
break;
case 2: //0101
digitalWrite(motor_pin_1, LOW);
digitalWrite(motor_pin_2, HIGH);
digitalWrite(motor_pin_3, LOW);
digitalWrite(motor_pin_4, HIGH);
break;
case 3: //1001
digitalWrite(motor_pin_1, HIGH);
digitalWrite(motor_pin_2, LOW);
digitalWrite(motor_pin_3, LOW);
digitalWrite(motor_pin_4, HIGH);


6. Remplace todos los Stepper por MotorDC. Debería quedar de esta forma:

/*
MotorDC.cpp basado en:
Stepper.cpp - - MotorDC library for Wiring/Arduino - Version 0.4
*/

#include "MotorDC.h"

/*
* two-wire constructor.
* Sets which wires should control the motor.
*/

MotorDC::MotorDC(int number_of_steps, int motor_pin_1, int motor_pin_2)
{
this->step_number = 0; // which step the motor is on
this->speed = 0; // the motor speed, in revolutions per minute
this->direction = 0; // motor direction
this->last_step_time = 0; // time stamp in ms of the last step taken
this->number_of_steps = number_of_steps; // total number of steps for this motor

// Arduino pins for the motor control connection:
this->motor_pin_1 = motor_pin_1;
this->motor_pin_2 = motor_pin_2;
// setup the pins on the microcontroller:
pinMode(this->motor_pin_1, OUTPUT);
pinMode(this->motor_pin_2, OUTPUT);

// When there are only 2 pins, set the other two to 0:
this->motor_pin_3 = 0;
this->motor_pin_4 = 0;
// pin_count is used by the stepMotor() method:
this->pin_count = 2;
}
/*
* constructor for four-pin version
* Sets which wires should control the motor.
*/
MotorDC::MotorDC(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4)
{
this->step_number = 0; // which step the motor is on
this->speed = 0; // the motor speed, in revolutions per minute
this->direction = 0; // motor direction
this->last_step_time = 0; // time stamp in ms of the last step taken
this->number_of_steps = number_of_steps; // total number of steps for this motor
// Arduino pins for the motor control connection:
this->motor_pin_1 = motor_pin_1;
this->motor_pin_2 = motor_pin_2;
this->motor_pin_3 = motor_pin_3;
this->motor_pin_4 = motor_pin_4;
// setup the pins on the microcontroller:
pinMode(this->motor_pin_1, OUTPUT);
pinMode(this->motor_pin_2, OUTPUT);
pinMode(this->motor_pin_3, OUTPUT);
pinMode(this->motor_pin_4, OUTPUT);
// pin_count is used by the stepMotor() method:
this->pin_count = 4;
}
/*
Sets the speed in revs per minute
*/
void MotorDC::setSpeed(long whatSpeed)
{
this->step_delay = 60L * 1000L / this->number_of_steps / whatSpeed;
}
/*
Moves the motor steps_to_move steps. If the number is negative,
the motor moves in the reverse direction.
*/

void MotorDC::step(int steps_to_move)
{
int steps_left = abs(steps_to_move); // how many steps to take
// determine direction based on whether steps_to_mode is + or -:
if (steps_to_move > 0) {this->direction = 1;}
if (steps_to_move < 0) {this->direction = 0;}
// decrement the number of steps, moving one step each time:
while(steps_left > 0) {
// move only if the appropriate delay has passed:
if (millis() - this->last_step_time >= this->step_delay) {
// get the timeStamp of when you stepped:
this->last_step_time = millis();
// increment or decrement the step number,
// depending on direction:
if (this->direction == 1) {
this->step_number++;
if (this->step_number == this->number_of_steps) {
this->step_number = 0;
}
}
else {
if (this->step_number == 0) {
this->step_number = this->number_of_steps;
}
this->step_number--;
}
// decrement the steps left:
steps_left--;
// step the motor to step number 0, 1, 2, or 3:
stepMotor(this->step_number % 4);
}
}
}
/*
* Moves the motor forward or backwards.
*/

void MotorDC::stepMotor(int thisStep)
{
if (this->pin_count == 2) {
switch (thisStep) {
case 0: /* 01 */
digitalWrite(motor_pin_1, LOW);
digitalWrite(motor_pin_2, HIGH);
break;
}
}
if (this->pin_count == 4) {
switch (thisStep) {
case 0: // 1010
digitalWrite(motor_pin_1, HIGH);
digitalWrite(motor_pin_2, LOW);
break;
}
}
}
/*
version() returns the version of the library:
*/

int MotorDC::version(void)
{
return 4;
}

7. Con el archivo MotorDC.h simplemente reemplace el Stepper por MotorDC, debería quedar de esta forma:

/*
MotorDC.h basado en:
Stepper.h - - Stepper library for Wiring/Arduino - Version 0.4
*/
// ensure this library description is only included once
#ifndef MotorDC_h
#define MotorDC_h
// library interface description
class MotorDC {
public:
// constructors:
MotorDC(int number_of_steps, int motor_pin_1, int motor_pin_2);
MotorDC(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4);
// speed setter method:
void setSpeed(long whatSpeed);
// mover method:
void step(int number_of_steps);
int version(void);
private:
void stepMotor(int this_step);
int direction; // Direction of rotation
int speed; // Speed in RPMs
unsigned long step_delay; // delay between steps, in ms, based on speed
int number_of_steps; // total number of steps this motor can take
int pin_count; // whether you're driving the motor with 2 or 4 pins
int step_number; // which step the motor is on
// motor pin numbers:
int motor_pin_1;
int motor_pin_2;
int motor_pin_3;
int motor_pin_4;
long last_step_time; // time stamp in ms of when the last step was taken
};
#endif


8. Abre el programa Arduino y verifica que se encuentre la librería MotorDC


9. Aquí un ejemplo de programa


#include MotorDC //poner simbolos

#define motorSteps 96

#define motorPin1 8
#define motorPin2 9
#define ledPin 13
#define enablePin 11

// initialize of the MotorDC library:
MotorDC myMotorDC1(motorSteps, motorPin1,motorPin2);
MotorDC myMotorDC2(motorSteps, motorPin2,motorPin1);
//crear dos inicializaciones, con los pines al reves para darle polaridad

void setup() {

myMotorDC1.setSpeed(5);
myMotorDC2.setSpeed(5);
//probar las velocidades, la mejor es 5

// Initialize the Serial port:
Serial.begin(9600);
}

void loop() {
// Step forward 100 steps:
Serial.println("Forward");

myMotorDC1.step(10);
//el motor va a girar de cuerdo a la cantidad de pasos

digitalWrite(motorPin1, LOW);
digitalWrite(motorPin2, LOW);
//aqui detiene el motor
delay(1000);

Serial.println("Backward");

myMotorDC2.step(-10);
//el motor va a girar de cuerdo a la cantidad de pasos

digitalWrite(motorPin1, LOW);
digitalWrite(motorPin2, LOW);
delay(1000);
//aqui detiene el motor
}


10. Ejemplo de conexión. Pin 8 y Pin 9



10. Aun falta por mejorar. Por ejemplo colocarle un while y un sensor de tacto, para poder manejar las rotaciones o el tiempo de rotación.

Descargue aquí los archivos y el ejemplo
Archivos MotorDC.zip





Espero que les sirva.