IMG_4409.jpeg

# Lab 2: Line Follower ### Objective In this lab, you will build a robot car and program it to follow a black line on a white surface. ### Materials * Arduino Uno board * Robot car chassis kit * Infrared (IR) line tracking sensors * Motor driver module (e.g., L298N) * Jumper wires * US...

# Lab 2: Line Follower ### Objective In this lab, you will build a robot car and program it to follow a black line on a white surface. ### Materials * Arduino Uno board * Robot car chassis kit * Infrared (IR) line tracking sensors * Motor driver module (e.g., L298N) * Jumper wires * USB cable * Power source (e.g., batteries) ### Procedure #### Hardware Setup 1. **Assemble the Robot Car Chassis:** * Follow the instructions included in your robot car chassis kit to assemble the frame, wheels, and motors. 2. **Mount the IR Line Tracking Sensors:** * Attach the IR line tracking sensors to the front of the robot car, ensuring they are close to the surface and aligned to detect the line. 3. **Connect the Motors:** * Connect the motors to the motor driver module. Typically, the motor driver module will have screw terminals for connecting the motor wires. 4. **Connect the Motor Driver to Arduino:** * Connect the motor driver module to the Arduino board using jumper wires. You'll need to connect the enable (EN) pins, input (IN) pins, and power (VCC and GND) pins. 5. **Connect the IR Sensors to Arduino:** * Connect the digital output pins of the IR line tracking sensors to digital input pins on the Arduino board. Also, connect the VCC and GND pins of the sensors to the Arduino's 5V and GND pins, respectively. 6. **Power the Robot Car:** * Connect the power source (batteries) to the motor driver module #### Software Setup 1. **Arduino IDE:** * Download and install the Arduino IDE from the official Arduino website ([https://www.arduino.cc](https://www.arduino.cc)). 2. **Libraries:** * Ensure you have the necessary libraries installed. For the motor driver, you might need to install a specific library if required by your module. #### Code Implementation 1. **Basic Structure:** * Start by defining the pins for the motors and IR sensors. * In the `setup()` function, initialize the serial communication and set the sensor pins as inputs and motor control pins as outputs. * In the `loop()` function, read the values from the IR sensors and control the motors based on these values to keep the robot car following the line. 2. **Reading Sensor Values:** * Use `digitalRead()` to read the values from the IR sensors. The sensors will typically output a LOW signal when they detect the black line and a HIGH signal when they are over a white surface. 3. **Motor Control Logic:** * Implement the logic to control the motors based on the sensor readings. For example: * If both sensors are over the white surface, move forward. * If the left sensor is over the black line, turn right. * If the right sensor is over the black line, turn left. * Use `digitalWrite()` or `analogWrite()` to control the speed and direction of the motors via the motor driver module. 4. **Code Example:** ```cpp // Define motor control pins const int motorLeftPin1 = 8; const int motorLeftPin2 = 9; const int motorRightPin1 = 10; const int motorRightPin2 = 11; // Define sensor pins const int leftSensorPin = 2; const int rightSensorPin = 3; void setup() { // Initialize serial communication Serial.begin(9600); // Set motor control pins as outputs pinMode(motorLeftPin1, OUTPUT); pinMode(motorLeftPin2, OUTPUT); pinMode(motorRightPin1, OUTPUT); pinMode(motorRightPin2, OUTPUT); // Set sensor pins as inputs pinMode(leftSensorPin, INPUT); pinMode(rightSensorPin, INPUT); } void loop() { // Read sensor values int leftSensorValue = digitalRead(leftSensorPin); int rightSensorValue = digitalRead(rightSensorPin); // Print sensor values to serial monitor for debugging Serial.print("Left Sensor: "); Serial.print(leftSensorValue); Serial.print(" , Right Sensor: "); Serial.println(rightSensorValue); // Motor control logic if (leftSensorValue == HIGH && rightSensorValue == HIGH) { // Move forward digitalWrite(motorLeftPin1, HIGH); digitalWrite(motorLeftPin2, LOW); digitalWrite(motorRightPin1, HIGH); digitalWrite(motorRightPin2, LOW); } else if (leftSensorValue == LOW && rightSensorValue == HIGH) { // Turn right digitalWrite(motorLeftPin1, HIGH); digitalWrite(motorLeftPin2, LOW); digitalWrite(motorRightPin1, LOW); digitalWrite(motorRightPin2, HIGH); } else if (leftSensorValue == HIGH && rightSensorValue == LOW) { // Turn left digitalWrite(motorLeftPin1, LOW); digitalWrite(motorLeftPin2, HIGH); digitalWrite(motorRightPin1, HIGH); digitalWrite(motorRightPin2, LOW); } else { // Stop digitalWrite(motorLeftPin1, LOW); digitalWrite(motorLeftPin2, LOW); digitalWrite(motorRightPin1, LOW); digitalWrite(motorRightPin2, LOW); } delay(10); // Small delay to prevent excessive looping } ``` 5. **Upload Code:** * Connect the Arduino board to your computer using a USB cable. * In the Arduino IDE, select the correct board and port. * Upload the code to the Arduino board. #### Testing and Calibration 1. **Initial Test:** * Place the robot car on the line and observe its behavior. It should try to follow the line. 2. **Calibration:** * Adjust the position of the IR sensors and the sensitivity to ensure accurate line tracking. * Modify the motor control logic and speed to optimize the robot's performance. You may need to adjust the delay times or the motor control signals to achieve smooth and accurate line following. 3. **Debugging:** * Use the serial monitor to print sensor values and debug any issues with the sensor readings or motor control logic. #### Expected Results * The robot car should be able to follow the black line on the white surface accurately. * The robot should make smooth turns and adjustments to stay on the line. #### Challenges * **Line Detection Issues:** * If the sensors are not consistently detecting the line, adjust their position or increase the sensitivity. * **Overshooting:** * If the robot overshoots the line during turns, reduce the motor speed or adjust the turning logic. * **Unstable Movement:** * If the robot moves erratically, check the sensor readings and motor connections. Also, ensure that the power supply is stable. This lab provides a foundation for understanding robotics, sensor integration, and motor control. You can expand upon this project by adding more sensors, implementing more advanced control algorithms, and integrating wireless communication for remote control and monitoring.