Building the Elegoo Smart Robot Car

The Elegoo Smart Robot Car is an autonomous mobile robot controlled by an Arduino Uno R3 microcontroller. The system is powered by 18650 LiPo batteries housed in a battery holder, supplying electrical energy to the hardware components through a custom Arduino shield and an L298N motor driver. Because the Arduino Uno cannot supply enough current or voltage directly to drive high-power inductive loads, the L298N motor driver acts as an intermediary switchboard, taking control signals from the Arduino and using external battery power to drive the four DC motors and turn the four tires. For autonomous navigation, the robot uses a 3-element line sensor mounted on the chassis to detect surface contrasts, allowing the system to follow a designated path by reading digital or analog reflection values. Additionally, an HC-SR04 ultrasonic sensor paired with an SG90 servo motor allows the robot to sweep the environment, measure distances using sound waves, and avoid obstacles. A Bluetooth module is also included to enable wireless serial communication, letting users send commands to the robot remotely. All operational logic is programmed using the Arduino IDE, processing input from the sensors and translating it into motor commands to achieve autonomous movement.