C.E.R.T.H.

For the purpose of assisting visually impaired individuals in elevator operation, a hardware topology of three devices has been developed. The key idea behind the proposed solution is to enable the use of the elevator through a remote control device equipped with braille system input capability and Bluetooth connectivity.

The system comprises individual remote controls assigned to each user, floor units situated within each push button box of an elevator installation, and a gateway device positioned inside the elevator’s cabin. Each of these devices is outfitted with a microcontroller supporting Bluetooth Low Energy (BLE) protocol communication.

The remote controls scan for Bluetooth services nearby, advertised by both the floor unit and the braille gateway, in order to connect. As the user approaches the elevator on a specific floor, it establishes a connection with the corresponding floor unit which acts as a virtual button summoning the elevator to the specific floor. Subsequently, when a visually impaired individual enters the elevator’s cabin, the braille gateway initiates a connection procedure with the remote control establishing an encrypted secure link. Upon a successful connection between the remote control and the braille gateway, the user can input floor preference using braille coding. After a valid input, the braille gateway interprets the command and sends it to the lift’s CAN network for execution.

A notification system, including a buzzer and a vibration motor, is integrated into the remote control to notify the user of connection/disconnection events and valid/invalid command inputs. Warning or informational events are conveyed through different audio frequencies and durations to capture the user’s attention. The braille gateway supports up to six simultaneous remote control connections and handles each user’s command on a first come, first serve basis. Additionally, it retains users’ floor preference data, enabling transportation to a predefined floor without requiring interaction with the remote control.

Special attention has been given to the programming of the remote control device in order to achieve low power consumption. The device can be awakened with the press of a button, while an activity timer monitors usage and switches the device to shutdown mode if it remains inactive for a predefined amount of time.