Nowadays, technological advancements are progressing rapidly, yet there are still some areas that rely on conventional methods, such as the use of physical keys for locker security. This study discusses how to design a simple security system for storage lockers using BLE (Bluetooth Low Energy) technology and IoT (Internet of Things), as well as measuring the response speed of the ESP32 microcontroller with a BLE Tag and the effect of distance on the voltage required by the ESP32 and BLE Tag when unlocking the locker. Additionally, the study examines the time required to request locker access via Telegram and evaluates the reliability of the security system from the perspectives of BLE Tag and Telegram. The research resulted in a system that uses an ESP32 microcontroller paired with a BLE Tag to access lockers. The ESP32 can respond to the BLE Tag's signals in a very short time, with an average delay of less than one second. Furthermore, the Telegram bot delay was measured using the Wireshark application, yielding an average delay of 600 milliseconds. The Telegram bot only grants access to users registered in the ESP32 program and will deny access to unregistered users. Registered users can only access one locker at a time. The ESP32 cannot respond to Bluetooth Low Energy signals from smartphones, even if they have the same Characteristic UUID and Service UUID as the BLE Tag. With the security system design using BLE Tag, it can increase security in the key storage lockers of the Jakarta Global University laboratory room.
Keyword: Locker, Bluetooth Low Energy, BLE, ESP32, Solenoid, Smart Keyless Locker, BLE Tag, Laboratory Key Locker