DC Motor Speed Control using Arduino

DC Motor Speed Control using Arduino UNO

Pulse Width Modulation (PWM)

Motor Controller L298

Algorithm design and descrition

• Speed Control of DC Motor using PIC Microcontroller
• DC Motor Speed Control with Arduino in Proteus ISIS
• Direction Control of DC Motor using Arduino in Proteus
• DC Motor Drive Circuit in Proteus ISIS

#include <LiquidCrystal.h>
//Keyboard Controls:
//
// C - Clockwise
// S - Stop
// A - Anti-clockwise

// Declare L298N Controller pins
// Motor 1
int count=255;
int dir1PinA = 2;
int dir2PinA = 5;
int speedPinA = 6; // PWM control
LiquidCrystal lcd(8, 9, 10, 11, 12, 13);

void setup() { 
 
Serial.begin(9600); // baud rate

lcd.begin(20, 4);
lcd.setCursor(5,0);
lcd.print("DC Motor");
lcd.setCursor(5,1);
lcd.print("Direction");
lcd.setCursor(5,2);
lcd.print("Control");
lcd.setCursor(2,3);
lcd.print("via Arduino UNO");

delay(3000);

lcd.clear ();

lcd.setCursor(0,2);
lcd.print("www.TheEngineering");
lcd.setCursor(4,3);
lcd.print("Projects.com");
//Define L298N Dual H-Bridge Motor Controller Pins

pinMode(dir1PinA,OUTPUT);
pinMode(dir2PinA,OUTPUT);
pinMode(speedPinA,OUTPUT);

analogWrite(speedPinA, 255);//Sets speed variable via PWM 

}

void loop() {

// Initialize the Serial interface:

if (Serial.available() > 0) {
int inByte = Serial.read();
int speed; // Local variable

switch (inByte) {

case 'C': // Clockwise rotation
//analogWrite(speedPinA, 255);//Sets speed variable via PWM 
digitalWrite(dir1PinA, LOW);
digitalWrite(dir2PinA, HIGH);
Serial.println("Clockwise rotation"); // Prints out “Motor 1 Forward” on the serial monitor
Serial.println("   "); // Creates a blank line printed on the serial monitor
//lcd.clear();
lcd.setCursor(0,0);
lcd.print("Clockwise rotation");
break;

case 'S': // No rotation
//analogWrite(speedPinA, 0); // 0 PWM (Speed)
digitalWrite(dir1PinA, LOW);
digitalWrite(dir2PinA, LOW);
Serial.println("No rotation");
Serial.println("   ");
//lcd.clear();
lcd.setCursor(0,0);
lcd.print("No rotation");
break;

case 'H': //Accelrating motor
count=count+20;
  if (count>255)
  {
  count =255;
  }
  analogWrite(speedPinA,count);
  delay(50);

//digitalWrite(dir1PinA, LOW);
//digitalWrite(dir2PinA, HIGH);
Serial.println("Motor is accelrating slowly");
Serial.println("   ");
Serial.println(count);
lcd.setCursor(0,0);
lcd.print("Motor is accelrating");
break;

case 'L': //Deaccelrating motor
count=count-20;
  if (count<20)
  {
  count=20;
  }
  analogWrite(speedPinA,count);
  delay(50);

//digitalWrite(dir1PinA, LOW);
//digitalWrite(dir2PinA, HIGH);
Serial.println("Motor is deaccelrating slowly");
Serial.println("   ");
Serial.println(count);
lcd.setCursor(0,0);
lcd.print("Motor Deaccelrates");
break;

case 'A': // Anti-clockwise rotation
//analogWrite(speedPinA, 255); // Maximum PWM (speed)
digitalWrite(dir1PinA, HIGH);
digitalWrite(dir2PinA, LOW);
Serial.println("Anti-clockwise rotation");
Serial.println("   ");
//lcd.clear();
lcd.setCursor(0,0);
lcd.print("Anti-clockwise");
break;

default:
// Turn off the motor if any other key is being pressed
for (int thisPin = 2; thisPin < 11; thisPin++) {
digitalWrite(thisPin, LOW);
}
Serial.println("Wrong key is pressed");
//lcd.clear();
lcd.setCursor(0,0);
lcd.print("Wrong key is pressed");
  }
    }
      }

• In the previous tutorials, DC Motor Direction Control using Arduino and DC Motor Direction Control using Matlab we have learnt that how to control the direction of the DC motor.
• We used the commands C, A and S for the clockwise rotation, anti clockwise rotation and stopping the motor respectively.
• In this tutorial, we have added two further commands H and L for accelerating and de-accelerating the DC motor.
• If we send the command H different times consecutively the speed of the motor will increase continuously.
• If we send the command L different times consecutively, the speed of the motor will start to decrease.
• Now, upload the source code to your Arduino UNO's board.
• Open the serial monitor at the top right of the Arduino Software.
• And enter the commands in serial monitor periodically as explained above.

Actual Hardware Setup

• When we enter the command C in the serial monitor of the Arduino software. Motor will start rotating in the clockwise direction and a statement Clockwise rotation will be printed on serial port.
• The same statement will be printed on the LCD as well as shown in the figure below.

• When we enter the command A in the serial monitor of the Arduino software. Motor will start rotating in the anti clockwise direction and a statement Anti clockwise rotation will be printed on serial port.
• The same statement will be printed on the LCD as well as shown in the figure below.

• When we enter the command H in the serial monitor of the Arduino software. Motor will start accelerating and a statement Motor is accelerating will be printed on serial port.
• The same statement will be printed on the LCD as well as shown in the figure below.

• When we enter the command L in the serial monitor of the Arduino software. Motor will start to deaccelerate and a statement Motor Deaccelerates will be printed on serial port.
• The same statement will be printed on the LCD as well as shown in the figure below.