The Engineering Projects

Line Following Robotic Waiter using Arduino

Hello friends, I hope you all are fine and having fun with your lives. Today, I am going to share a new project which is Line Following Robotic Waiter. I hope you guys are gonna enjoy it. I have shared all the details below so that if you wanna design it then you can easily do it. I have designed this project for a client and it worked quite perfectly so I thought to share it with you guys as well.

I have designed this Line Following Robotic Waiter using Arduino UNO board. I have also shared the code below and have given all the instructions but still if you got into any problem then ask in comments and I will solve your problems. I have also shared a video below which will show you the working of Line Following robotic Waiter. So, let's get started with it:

Line Following Robotic Waiter

First of all, let's have an overview of this Line Following Robotic Waiter:

Overview

• In this project, I have designed an arena which has four tables on it as shown in below figure:

• The robot will start from the Table 1 side and whenever someone call it from any table then it will reach that table and take the order.
• After taking the order it will move back and will reach to the starting point again and wait for the next table call.
• Now let's have a look at the components required to design thi Line Following Robotic Waiter:

Components

• Let's have a look at the components list, which is required for designing this Robot. Here it is:
• Arduino UNO
• DC Motors
• RF Module
• 2 Relay Board
• IR Sensors
• These are the components required in order to design this Line following robotic waiter.

Mechanical Design

• I have designed a three wheeler robot in which there were two wheels at the front side with DC motors while a free caster wheel at the back side.
• I have used Acrylic Sheet as the body of the robot.
• The DC Motor I have used for designing this project is shown in the below figure:

• The caster wheel used is shown in below figure:

• The coupled DC gear Motor with wheel is shown in below figure:

• So I have designed two of such coupled motors and then combining all the above things together, we finally designed our Line Following Robotic Waiter as shown in below figure:

• Now our mechanical Design is ready so let's design the electronic hardware:

Electronic Circuit Design

• First of all, I have designed the DC Motor Driver which is also called 2 Relay Board.
• This circuit diagram is shown in below figure:

• Now in order to apply the signals to move the Motors I have used Arduino UNO board.
• Moreover I have placed four IR sensors below this robot.
• Two of these IR sensors are used for line tracking while the remaining two were placed on the sides for detecting the tables on both sides.
• I have also designed a power supply to convert 12V into 5V.
• The circuit diagram of power supply is as follows:

• So, now let's have a look at the Arduino code required for Line Following Robotic Waiter:

Arduino Code

• Here's the Arduino Code requried for Line Following Robotic Waiter.

#define motorL1 8
#define motorL2 9
#define motorR1 10
#define motorR2 11

#define PwmLeft 5
#define PwmRight 6

#define SensorR 2
#define SensorL 3
#define Sensor3 A0
#define Sensor4 A1

#define TableA A4
#define TableB A2
#define TableC A5
#define TableD A3

int OriginalSpeed = 200;
int TableCount = 0;
int TableCheck = 0;
int RFCheck = 10;

void setup() 
{
  Serial.begin (9600);
 
  pinMode(motorR1, OUTPUT);
  pinMode(motorR2, OUTPUT);
  pinMode(motorL1, OUTPUT);
  pinMode(motorL2, OUTPUT);
  
  pinMode(PwmLeft, OUTPUT);
  pinMode(PwmRight, OUTPUT);
  
  pinMode(SensorL, INPUT);
  pinMode(SensorR, INPUT);
  pinMode(Sensor3, INPUT);
  pinMode(Sensor4, INPUT);
  
  pinMode(TableA, INPUT);
  pinMode(TableB, INPUT);
  pinMode(TableC, INPUT);
  pinMode(TableD, INPUT);
  
  MotorsStop();
  
  analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
  delay(2000); 
 // Serial.println("fghfg");
  
}

void loop() {
  MotorsForward();
if((digitalRead(Sensor3) == LOW) && (TableCheck == 0)){TableCount++; TableCheck = 1;}
if((digitalRead(Sensor3) == HIGH) && (TableCheck == 1)){TableCheck = 2;}

if((digitalRead(Sensor3) == LOW) && (TableCheck == 2)){TableCount++; TableCheck = 3;}
if((digitalRead(Sensor3) == HIGH) && (TableCheck == 3)){TableCheck = 4;}
if((digitalRead(Sensor3) == LOW) && (TableCheck == 4)){TableCount++; TableCheck = 5;}
if((digitalRead(Sensor3) == HIGH) && (TableCheck == 5)){TableCheck = 0;}

if(digitalRead(TableA) == HIGH){RFCheck = 1;}
if(digitalRead(TableB) == HIGH){RFCheck = 2;}
if(digitalRead(TableC) == HIGH){RFCheck = 3;}
if(digitalRead(TableD) == HIGH){RFCheck = 4;}

if(RFCheck == TableCount){Table1();}
PIDController();
}

void MotorsBackward()
{
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, LOW);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, LOW);
}

void MotorsForward()
{
    digitalWrite(motorL1, LOW);
    digitalWrite(motorL2, HIGH);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
}

void MotorsStop()
{
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, HIGH);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, HIGH);
}

void MotorsLeft()
{
    analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
    digitalWrite(motorR1, HIGH);
    digitalWrite(motorR2, HIGH);
    digitalWrite(motorL1, LOW);
    digitalWrite(motorL2, HIGH);
}

void MotorsRight()
{
      analogWrite(PwmLeft, 0); 
  analogWrite(PwmRight, 0);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, HIGH);
}

void Motors180()
{
    analogWrite(PwmLeft, 0); 
    analogWrite(PwmRight, 0);
    digitalWrite(motorL1, HIGH);
    digitalWrite(motorL2, LOW);
    digitalWrite(motorR1, LOW);
    digitalWrite(motorR2, HIGH);
}

void PIDController()
{
  if(digitalRead(SensorL) == HIGH){analogWrite(PwmRight, 250);analogWrite(PwmLeft, 0);}
  if(digitalRead(SensorR) == HIGH){analogWrite(PwmLeft, 250);analogWrite(PwmRight,0);}
  if((digitalRead(SensorL) == LOW) && (digitalRead(SensorR) == LOW)){analogWrite(PwmRight, 0);analogWrite(PwmLeft, 0);}
}

void Table1()
{
   TableCount = 0;
   MotorsRight();
   delay(4000);
   while(digitalRead(SensorR) == HIGH);
   while(digitalRead(SensorL) == HIGH);
   while(1)
   {
       MotorsForward();
       PIDController();
       if(digitalRead(Sensor3) == LOW){break;}
   }
   MotorsStop();
   delay(1000);
   Motors180();
   delay(2000);
   while(digitalRead(Sensor3) == HIGH);
   while(digitalRead(Sensor3) == LOW);
   while(digitalRead(SensorL) == HIGH);
   //delay(500);
   while(1)
   {
   MotorsForward();
   PIDController();
   if(digitalRead(Sensor3) == LOW){break;}
   }
   //delay(1000);
   MotorsLeft();
   delay(4000);
   while(digitalRead(SensorL) == HIGH);
   while(digitalRead(SensorR) == LOW);
   while(1)
   {
       MotorsForward();
       PIDController();
       if(digitalRead(Sensor3) == LOW){break;}
   }
   MotorsStop();
   delay(1000);
}

• This code will not work for you exactly.
• The robot is following the line so I have placed some value for IR sensors so that my robot can follow.
• When right IR sensor is HIGH then right motor moves a little faster and left motor slows down.
• In this way I am making it to follow the line so you have to change such values in the code.
• If you got into any issue regarding this project then add us on Skype and we will help you out.
• Here's our final robot looks like:

• Here's the video of Line following Robotic Waiter which will give you the better idea of how it worked:

That's all for today, I hope you have enjoyed today's project. Will meet you guys in the next tutorial. till then take care and have fun !!! :)