Smart Car

Arduino Smart Car

Components

Arduino Uno Board

Sensor Shield

Servo Motor

DC Motors

L298N H-Bridge

Ultrasonic Sensor

Line Tracking Sensor

Jumper Wires

Lithium Battery

Battery Pack

Chassis

Wheels

Assembly Instructions

Instructions_Comments.pdf

Wiring the Robot

robot-car-instructions.pdf

Programming the Robot

Moving the Servo Motor



//Setup for Servo Motor

#include <Servo.h>

Servo myservo;

void setup() {
    Serial.begin(9600);
    myservo.attach(11);
 
}

void loop() {
  
    myservo.write(90);
    delay(500);
  

    myservo.write(0);
    delay(1000);

    myservo.write(180);
    delay(1000);

}

Using the Ultrasonic Sensor

//Setup for Ultrasonic sensor

#include <SR04.h>

#define trig_pin 13
#define echo_pin 12

SR04 sr04 = SR04(echo_pin,trig_pin);

int pos = 0;
int leftDis = 0;
int rightDis = 0;
int forward = 0;



void setup() {
  Serial.begin(9600);
 
}

void loop() {
  
    myservo.write(80);
    delay(500);
  
    forward = sr04.Distance();
    Serial.println(forward);

    myservo.write(0);
    delay(1000);
    rightDis = sr04.Distance();
    Serial.println(leftDis);
    delay(1000);
  
    myservo.write(180);
    delay(1000);
    leftDis = sr04.Distance();
    Serial.println(rightDis);
    delay(1000);

    

}

Moving the Wheels

//Setup for Wheel Motors

#define enA 6
#define in1 7
#define in2 5
#define enB 3
#define in3 4
#define in4 2

void go() {
  analogWrite(enA, 175);
  analogWrite(enB, 175);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void left() {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, LOW);
  digitalWrite(in4, HIGH);
}

void right() {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void stopp() {
  digitalWrite(enA, LOW);
  digitalWrite(enB, LOW);
}

void setup() {
  Serial.begin(9600);
  pinMode(enA, OUTPUT);
  pinMode(enB, OUTPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
  pinMode(in3, OUTPUT);
  pinMode(in4, OUTPUT);
 
}

void loop() {
  
    go();
    delay(1000);
    stopp();
    delay(1000);

}

Moving the Wheels Simplified

//Setup for Wheel Motors

#define enA 6
#define in1 7
#define in2 5
#define enB 3
#define in3 4
#define in4 2

void go(int t) {
  analogWrite(enA, 175);
  analogWrite(enB, 175);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
  delay(t);
  stopp(250);

}

void left(int t) {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, LOW);
  digitalWrite(in4, HIGH);
  delay(t);
  stopp(250);
}

void right(int t) {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
  delay(t);
  stopp(250);
}

void stopp(int t) {
  digitalWrite(enA, LOW);
  digitalWrite(enB, LOW);
  delay(t);
}

void setup() {
  Serial.begin(9600);
  pinMode(enA, OUTPUT);
  pinMode(enB, OUTPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
  pinMode(in3, OUTPUT);
  pinMode(in4, OUTPUT);
 
}

void loop() {
  
    go(1000);
    right(500);
    
}

Stationary Robot

//Ultrasonic Setup
#include <SR04.h>

#define echo_pin 12
#define trig_pin 13

SR04 sr04 = SR04(echo_pin,trig_pin);

int distance = 0;
int rightDis = 0;
int leftDis = 0;

//Setup for Servo Motor

#include <Servo.h>

Servo myservo;

//Setup for Wheel Motors

#define enA 6
#define in1 7
#define in2 5
#define enB 3
#define in3 4
#define in4 2

void go() {
  analogWrite(enA, 175);
  analogWrite(enB, 175);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void left() {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, LOW);
  digitalWrite(in4, HIGH);
}

void right() {
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void stopp() {
  digitalWrite(enA, LOW);
  digitalWrite(enB, LOW);
}

void setup() {
  Serial.begin(9600);
  myservo.attach(11);
  pinMode(enA, OUTPUT);
  pinMode(enB, OUTPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
  pinMode(in3, OUTPUT);
  pinMode(in4, OUTPUT);
 
}

void loop() {
  myservo.write(90);
  distance = sr04.Distance();
  if (distance < 50) 
  {
    Serial.println("Stop");
    
    myservo.write(0);
    delay(1000);
    rightDis = sr04.Distance();
    Serial.print("Right: ");
    Serial.println(rightDis);

  else 
  {
    Serial.println("Go");
  }
  delay(500);


}

Obstacle Avoidance

//Setup for Ultrasonic sensor

#include <SR04.h>

#define trig_pin 13
#define echo_pin 12

SR04 sr04 = SR04(echo_pin,trig_pin);

//Setup for Servo Motor

#include <Servo.h>

Servo myservo;

int leftDis = 0;
int rightDis = 0;
int forwardDis = 0;

//Setup for Wheel Motors

#define enA 6
#define in1 7
#define in2 5
#define enB 3
#define in3 4
#define in4 2

void go() {   //Forward Movement
  analogWrite(enA, 175);
  analogWrite(enB, 175);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void back() {   //Reverse Movement
  analogWrite(enA, 175);
  analogWrite(enB, 175);
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  digitalWrite(in3, LOW);
  digitalWrite(in4, HIGH);
}

void left() {   //Turning Left
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  digitalWrite(in3, LOW);
  digitalWrite(in4, HIGH);
}

void right() {    //Turning Right
  analogWrite(enA, 150);
  analogWrite(enB, 150);
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  digitalWrite(in3, HIGH);
  digitalWrite(in4, LOW);
}

void stopp() {    //Stops robot
  digitalWrite(enA, LOW);
  digitalWrite(enB, LOW);
}

void setup() {
  Serial.begin(9600);
  myservo.attach(11);
  pinMode(enA, OUTPUT);
  pinMode(enB, OUTPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
  pinMode(in3, OUTPUT);
  pinMode(in4, OUTPUT);
 
}

void loop() {
  
  myservo.write(80);
  delay(500);
  
  forwardDis = sr04.Distance();
  Serial.println(forwardDis);

  if (forwardDis < 75) { //Object is in front of robot
    stopp();   //Stops robot movement
    delay(250);
    back();   //backs away from object slightly
    delay(500);
    stopp();
    delay(1000);

    myservo.write(0);   //Moves US Sensor to the right
    delay(1000);
    rightDis = sr04.Distance();   //Measures Distance
    Serial.println(leftDis);    //Optional print to Serial Monitor
    delay(1000);
  
    myservo.write(180);   //Moves US Sensor to the left
    delay(1000);
    leftDis = sr04.Distance();    //Measures Distance
    Serial.println(rightDis);   //Optional print to Serial Monitor
    delay(1000);

    if(rightDis > leftDis){   //Path is clearest to the right
        right();    //turns robot to the right 90ish degrees
        delay(15);
    }
    else if(rightDis < leftDis) {   //Path clearest to the left
        left();   //turns robot to the left 90ish degrees
        delay(15);
    }
    
    myservo.write(80);    //Moves US Sensor back to the forward position
    delay(250);
  }

  else{   //While there is not objects in the way
    go();   //Moves robot forward
  }
  

}

Bluetooth

unsigned char Bluetooth_val;       //defining variable val
#define Lpwm_pin  6    //adjusting speed  
#define Rpwm_pin  3    //adjusting speed  //
int pinLB=7;     // defining pin2 left rear
int pinLF=5;     // defining pin4 left front
int pinRB=4;    // defining pin7 right rear
int pinRF=2;    // defining pin8 right front
unsigned char Lpwm_val = 255;
unsigned char Rpwm_val = 255;
int Car_state=0;
void M_Control_IO_config(void)
{
  pinMode(pinLB,OUTPUT); // IN1
  pinMode(pinLF,OUTPUT); // IN2
  pinMode(pinRB,OUTPUT); // IN3 
  pinMode(pinRF,OUTPUT); // IN4
  pinMode(Lpwm_pin,OUTPUT); // pin 6 (PWM) 
  pinMode(Rpwm_pin,OUTPUT); // pin 3 (PWM)   
}
void Set_Speed(unsigned char Left,unsigned char Right)
{
  analogWrite(Lpwm_pin,Left);
  analogWrite(Rpwm_pin,Right);
}
void advance()     //  going forward
    {
     Set_Speed(200,200);
     digitalWrite(pinRB,HIGH);  // making motor move towards right rear
     digitalWrite(pinRF,LOW);
     digitalWrite(pinLB,HIGH);  // making motor move towards left rear
     digitalWrite(pinLF,LOW); 
     Car_state = 1;    
    }
void turnR()        //turning right(dual wheel)
    {
     Set_Speed(150,150);
     digitalWrite(pinRB,HIGH);  //making motor move towards right rear
     digitalWrite(pinRF,LOW);
     digitalWrite(pinLB,LOW);
     digitalWrite(pinLF,HIGH);  //making motor move towards left front
     Car_state = 4;
    }
void turnL()        //turning left(dual wheel)
    {
     Set_Speed(150,150);
     digitalWrite(pinRB,LOW);
     digitalWrite(pinRF,HIGH );   //making motor move towards right front
     digitalWrite(pinLB,HIGH);   //making motor move towards left rear
     digitalWrite(pinLF,LOW);
     Car_state = 3;
    }    
void stopp()         //stop
    {
     
     digitalWrite(pinRB,HIGH);
     digitalWrite(pinRF,HIGH);
     digitalWrite(pinLB,HIGH);
     digitalWrite(pinLF,HIGH);
     Car_state = 5;
    }
void back()          //back up
    {
     Set_Speed(200,200);
     digitalWrite(pinRB,LOW);  //making motor move towards right rear
     digitalWrite(pinRF,HIGH);
     digitalWrite(pinLB,LOW);  //making motor move towards left rear
     digitalWrite(pinLF,HIGH);
     Car_state = 2;   
    }
     
void setup() 
{ 
   M_Control_IO_config();
   Set_Speed(Lpwm_val,Rpwm_val);
   Serial.begin(9600);   //initialized serial port , using Bluetooth as serial port, setting baud at 9600 
   stopp(); 
}
void loop() 
{  
   if(Serial.available()) //to judge whether the serial port receives the data.
    {
     Bluetooth_val=Serial.read();
     Serial.print(Bluetooth_val);//reading (Bluetooth) data of serial port,giving the value of val;
    switch(Bluetooth_val)
     {
       case 'U':advance(); //UP
       break;
       case 'D': back();   //back
       break;
       case 'L':turnL();   //Left
       break;
       case 'R':turnR();  //Right
       break;
       case 'S':stopp();    //stop
       break;  
       case 'I':stopp();    //stop
       break;  
     }
    } 
}

Learn More

L298N H-Bridge

Ultrasonic Sensor

Servo Motors

Line Tracking