Firmware Class Diagram Design

Using the PlantUML, a tool to render UML diagrams, the first version of the class diagram was made thinking about the libraries and features we needed when testing the components.

1. Overview:

The Decentralized Ticket Entry System hardware assembly is composed of three primary modules: the Central Module, the Turnstile, and the Registration Module.

2. Modules Description:

2.1 Central Module:

• Power Source: Provides electrical power to the central module.
• Relay: An electrically operated switch. Interconnected with the bidirectional logic converter and the alarm buzzer in the Turnstile.
• Bidirectional Logic Converter: Enables communication and signal translation. Connected directly to the Raspberry Pi.
• Raspberry Pi: The computing brain of the system. Interfaces with the bidirectional logic converter, the variable voltage regulator, the TTL-USB Converter, Keypad, Webcam, Alarm Buzzer, Infrared Sensor, Servo Motor, and LCD Display in the Turnstile.
• Variable Voltage Regulator: Adjusts voltage outputs as necessary. Connected to the LCD Display, Servo Motor, and Infrared Sensor in the Turnstile.

2.2 Turnstile:

• Power Source: Provides electrical power to the turnstile.
• Fingerprint Scanner: Verifies user identity. Linked to the TTL-USB Converter.
• TTL-USB Converter: Facilitates digital communications. Connected to the Raspberry Pi in the Central Module and the Fingerprint Scanner in the Turnstile.
• Keypad: Allows user input. Directly interfaces with the Raspberry Pi.
• QR Code Scanner: Used to read QR Codes. Interconnected with the Raspberry Pi.
• Alarm Buzzer: Alerts in case of unauthorized access. Connected to the relay in the Central Module and the Raspberry Pi.