Bluetooth RC Car

Project Overview

The Bluetooth RC Car is a four-wheeled robotic vehicle controlled wirelessly via Bluetooth using an HC-05 module paired with a custom-built Android controller app. Powered by an Arduino UNO and an L298N dual motor driver, the car supports real-time directional commands, variable speed control, and a horn feature — all transmitted over a stable 10-metre Bluetooth range.

Key Features & Implementation

• Wireless Bluetooth Control: The HC-05 module communicates with a smartphone over RFCOMM serial protocol, receiving single-character command packets at 9600 baud for near-zero latency response.
• Variable Speed with PWM: The L298N driver receives PWM signals from the Arduino, allowing smooth acceleration and deceleration curves rather than abrupt on/off motor switching.
• Custom Android App: A dedicated app built with MIT App Inventor provides a joystick-style interface for intuitive directional control and a turbo-boost button for max speed bursts.

Challenges Solved

Bluetooth signal drops caused erratic motor behaviour when the connection was momentarily lost. A watchdog timer was implemented on the Arduino that automatically halts all motors if no valid command packet is received within 300ms, ensuring the car never runs away uncontrolled.