How to Build a Smart Helmet using Arduino?

The smart helmet project is divided into two main subsystems: a transmitter side mounted on the helmet and a receiver side integrated into the vehicle. On the transmitter side, an Arduino UNO R3 coordinates inputs from multiple safety sensors. An MQ-3 sensor monitors the rider's breath for alcohol content, while dual IR sensors confirm whether the helmet is physically being worn. If the MQ-3 detects alcohol beyond a safe threshold or if the IR sensors indicate the helmet is off, the Arduino triggers local visual and audible alerts via an LED and buzzer. Concurrently, it packs this telemetry data and beams it wirelessly using a 433 MHz RF transmitter module driven by the RadioHead (RH_ASK) library. On the receiver side, a matching 433 MHz RF receiver captures the wireless data packet. A second Arduino UNO R3 processes the incoming signal and updates a 16x2 LCD screen via an I2C interface to display the current system status. If the helmet checks pass successfully, the Arduino triggers a 1-Channel Relay Module to close the circuit, allowing power to flow to the vehicle ignition system, represented here by a demonstration BO motor. If a safety violation is flagged, the relay remains open, locking the engine and preventing the vehicle from starting.