Build an Arduino-powered robot that follows a black line, avoids obstacles using ultrasonic sensors, and operates a gate mechanism with servos.
⚠️ LiPo Battery Warning: Use a dedicated balance charger and never leave lithium batteries charging unattended.
Soldering basic wires, Arduino IDE installed on computer
A two-wheeled robot that follows a black line on a white surface, using IR reflectance sensors. It also features an ultrasonic sensor for obstacle avoidance and two servo motors: one for scanning and another for operating a 'gate' mechanism.
Two IR sensors detect the line edges; the Arduino processes these readings along with ultrasonic distance data to navigate. It drives the motors through an L298N driver and controls two servos for scanning and gate operations. The robot includes a calibration routine for the ultrasonic sensor and logic to stop and open a gate when both IR sensors detect black.
Follow the exact circuit connections and pinouts for your board.
| From Pin / Component | To Pin / Board | Connection Note |
|---|---|---|
| Digital Pin (e.g., D2) | IR Sensor (Left) OUT | For reading left sensor state |
| Digital Pin (e.g., D3) | IR Sensor (Right) OUT | For reading right sensor state |
| Digital Pin (e.g., D4) | L298N IN1 | Motor A direction control |
| Digital Pin (e.g., D5) | L298N IN2 | Motor A direction control |
| PWM Pin (e.g., D9) | L298N ENA | Motor A speed control (PWM) |
| Digital Pin (e.g., D6) | L298N IN3 | Motor B direction control |
| Digital Pin (e.g., D7) | L298N IN4 | Motor B direction control |
| PWM Pin (e.g., D10) | L298N ENB | Motor B speed control (PWM) |
| Digital Pin 10 (PWM) | L298N Motor Driver enA | Left Motor Speed Control |
| Digital Pin 9 | L298N Motor Driver in1 | Left Motor Direction 1 |
| Digital Pin 8 | L298N Motor Driver in2 | Left Motor Direction 2 |
| Digital Pin 7 | L298N Motor Driver in3 | Right Motor Direction 1 |
| Digital Pin 6 | L298N Motor Driver in4 | Right Motor Direction 2 |
| Digital Pin 5 (PWM) | L298N Motor Driver enB | Right Motor Speed Control |
| Analog Pin A0 | IR Sensor Left OUT | Left Line Sensor Input |
| Analog Pin A1 | IR Sensor Right OUT | Right Line Sensor Input |
| Analog Pin A2 | HC-SR04 Ultrasonic Echo | Ultrasonic Echo Pin |
| Analog Pin A3 | HC-SR04 Ultrasonic Trigger | Ultrasonic Trigger Pin |
| Analog Pin A5 | Servo (Scanning) Signal | Main Scanning Servo |
| Analog Pin A4 | Servo (Gate) Signal | Gate Control Servo |
| 5V | IR Sensors VCC, HC-SR04 VCC, Servos VCC | Power for sensors and servos |
| GND | L298N GND, IR Sensors GND, HC-SR04 GND, Servos GND | Common Ground |
| From Pin / Component | To Pin / Board | Connection Note |
|---|---|---|
| VCC | Arduino 5V | Power for IR sensors |
| GND | Arduino GND | Ground for IR sensors |
| From Pin / Component | To Pin / Board | Connection Note |
|---|---|---|
| OUT1/OUT2 | DC Gear Motor A | Connects to one motor |
| OUT3/OUT4 | DC Gear Motor B | Connects to the other motor |
| GND | Arduino GND | Common ground connection |
| 12V (or Battery VCC) | L298N VCC (Motor Power) | Connect to robot's main battery |
| OUT1, OUT2 | DC Geared Motor 1 | Connect to Left Motor |
| OUT3, OUT4 | DC Geared Motor 2 | Connect to Right Motor |
| From Pin / Component | To Pin / Board | Connection Note |
|---|---|---|
| Positive (+) | L298N +12V (or VIN) | Main power for motors and L298N |
| Negative (-) | L298N GND | Ground for main power |
Download and install the Arduino IDE. Install any necessary libraries for PID control (e.g., PID_v1 by Brett Beauregard) and potentially a motor driver library if available, though direct control is common for L298N.
Assemble your robot chassis according to its instructions. Mount the DC gear motors, wheels, and caster wheel. Securely attach the L298N motor driver, Arduino board, and IR reflectance sensor module(s) to the chassis, ensuring the sensors face downwards towards the track.
Connect the IR reflectance sensors to Arduino digital input pins. Connect the L298N motor driver's IN1, IN2, IN3, IN4 pins to Arduino digital output pins, and its ENA, ENB pins to Arduino PWM-capable digital output pins for speed control.
Upload the provided Arduino sketch to your Arduino board. Open the Serial Monitor and follow the on-screen instructions to calibrate the IR sensors for your specific track and lighting conditions. This typically involves moving the robot over the black line and white surface.
Connect the DC gear motors to the L298N motor driver's output terminals (OUT1/OUT2 for Motor A, OUT3/OUT4 for Motor B). Connect your battery pack to the L298N's power input (typically 12V or VIN). Place the robot on your track and adjust the PID constants (Kp, Ki, Kd) in the code to achieve smooth and fast line following.
Download and install the Arduino IDE if you haven't already. Copy the provided source code into a new sketch. No external libraries are strictly required as servo control is custom implemented.
Assemble your 2-wheel drive robot chassis. Mount the DC geared motors, wheels, and a caster wheel. Securely attach the Arduino board, L298N motor driver, IR sensors (facing downwards), ultrasonic sensor (facing forward), and the two servo motors (one for scanning, one for the gate mechanism) to the chassis.
Carefully follow the wiring diagram to connect the IR sensors, ultrasonic sensor, L298N motor driver, DC motors, and both servo motors to your Arduino board. Pay close attention to power (VCC/5V), ground (GND), and signal/control pin connections.
Connect your Arduino to your computer via USB. Select the correct board and port in the Arduino IDE, then upload the sketch. Open the Serial Monitor (9600 baud) to observe ultrasonic distance readings. Test motor directions and servo movements by manually triggering conditions or adding temporary test code.
Place the robot on your line-following track. Observe its behavior and adjust the analogWrite values for enA and enB (motor speeds) to find a balance between speed and control. Adjust the Set variable for the ultrasonic sensor to fine-tune obstacle detection distance. You may need to experiment with IR sensor placement or sensitivity.
Build an Arduino-powered robot that follows a black line, avoids obstacles using ultrasonic sensors, and operates a gate mechanism with servos.
⚠️ LiPo Battery Warning: Use a dedicated balance charger and never leave lithium batteries charging unattended.
Soldering basic wires, Arduino IDE installed on computer
A two-wheeled robot that follows a black line on a white surface, using IR reflectance sensors. It also features an ultrasonic sensor for obstacle avoidance and two servo motors: one for scanning and another for operating a 'gate' mechanism.
Two IR sensors detect the line edges; the Arduino processes these readings along with ultrasonic distance data to navigate. It drives the motors through an L298N driver and controls two servos for scanning and gate operations. The robot includes a calibration routine for the ultrasonic sensor and logic to stop and open a gate when both IR sensors detect black.
Download and install the Arduino IDE. Install any necessary libraries for PID control (e.g., PID_v1 by Brett Beauregard) and potentially a motor driver library if available, though direct control is common for L298N.
Assemble your robot chassis according to its instructions. Mount the DC gear motors, wheels, and caster wheel. Securely attach the L298N motor driver, Arduino board, and IR reflectance sensor module(s) to the chassis, ensuring the sensors face downwards towards the track.
Connect the IR reflectance sensors to Arduino digital input pins. Connect the L298N motor driver's IN1, IN2, IN3, IN4 pins to Arduino digital output pins, and its ENA, ENB pins to Arduino PWM-capable digital output pins for speed control.
Upload the provided Arduino sketch to your Arduino board. Open the Serial Monitor and follow the on-screen instructions to calibrate the IR sensors for your specific track and lighting conditions. This typically involves moving the robot over the black line and white surface.
Connect the DC gear motors to the L298N motor driver's output terminals (OUT1/OUT2 for Motor A, OUT3/OUT4 for Motor B). Connect your battery pack to the L298N's power input (typically 12V or VIN). Place the robot on your track and adjust the PID constants (Kp, Ki, Kd) in the code to achieve smooth and fast line following.
Download and install the Arduino IDE if you haven't already. Copy the provided source code into a new sketch. No external libraries are strictly required as servo control is custom implemented.
Assemble your 2-wheel drive robot chassis. Mount the DC geared motors, wheels, and a caster wheel. Securely attach the Arduino board, L298N motor driver, IR sensors (facing downwards), ultrasonic sensor (facing forward), and the two servo motors (one for scanning, one for the gate mechanism) to the chassis.
Carefully follow the wiring diagram to connect the IR sensors, ultrasonic sensor, L298N motor driver, DC motors, and both servo motors to your Arduino board. Pay close attention to power (VCC/5V), ground (GND), and signal/control pin connections.
Connect your Arduino to your computer via USB. Select the correct board and port in the Arduino IDE, then upload the sketch. Open the Serial Monitor (9600 baud) to observe ultrasonic distance readings. Test motor directions and servo movements by manually triggering conditions or adding temporary test code.
Place the robot on your line-following track. Observe its behavior and adjust the analogWrite values for enA and enB (motor speeds) to find a balance between speed and control. Adjust the Set variable for the ultrasonic sensor to fine-tune obstacle detection distance. You may need to experiment with IR sensor placement or sensitivity.
