Smart Bluetooth Tail Lamp (SBTL)

The Smart Bluetooth Tail Lamp (SBTL) is a wireless and detachable taillight system developed to enhance the safety and operational readiness of rescue boat trailers. Conventional trailer lighting systems are permanently installed and frequently exposed to water, mud, moisture, vibration, and impact during boat launching and retrieval operations. Repeated exposure may result in corrosion, damaged wiring, and electrical short circuits, leading to recurring maintenance and reduced asset availability. SBTL addresses these issues using an ESP32-based Bluetooth Master–Slave communication system integrated with a modular and detachable taillight design. The Master unit detects five lighting functions from the towing vehicle: brake light, left turn signal, right turn signal, tail/position light, and reverse light. The corresponding control data are transmitted wirelessly via Bluetooth to the Slave unit, which controls the trailer lights through Active-Low relays. A fail-safe mechanism switches off the Slave-controlled outputs when Bluetooth communication is interrupted and restores normal operation following successful reconnection. Prototype testing was conducted to evaluate the five lighting functions and four Bluetooth communication conditions. All nine test conditions were successfully passed, corresponding to a 100% functional test success rate under the tested conditions. The prototype correctly reproduced the required lighting functions, detected communication loss, activated the predefined fail-safe response, and resumed normal operation after reconnection. The detachable lighting unit was also demonstrated on a rescue boat trailer, allowing it to be removed before water exposure and reinstalled after operation. The results demonstrate the functional feasibility of SBTL as a wireless and detachable lighting solution for rescue boat trailers. The proposed system has the potential to reduce direct exposure of lighting components to harsh operating conditions and support safer and more reliable trailer operations. Further field testing is required to evaluate communication range, latency, environmental durability, and long-term reliability. Keywords— SBTL, ESP32, Bluetooth, wireless taillight, rescue boat trailer, fail-safe control.