Arduino Smart Vending Machine with Rfid and Keypad Control

We are seeking a skilled freelancer to develop a complete Arduino-based smart vending machine prototype. This project involves both software development (Arduino sketch) and hardware integration documentation (wiring diagram), along with a technical explanation of the design.

The core functionality requires an Arduino UNO to control a vending system. User authentication will be handled by an RC522 RFID module; the 4x4 membrane keypad should only become active after a successful card tap. Once authenticated, pressing '1' on the keypad should dispense a Snickers, and pressing '2' should dispense Skittles. Each dispensing action will be powered by a 5V stepper motor.

Deliverables for this project include:
- A fully functional, ready-to-upload Arduino sketch for the specified hardware.
- A clear and detailed wiring diagram illustrating all necessary connections between the Arduino UNO, RC522 RFID module, 4x4 membrane keypad, and the two 5V stepper motors.
- A concise technical document outlining the main design decisions, component interactions, and overall system logic.

This is a university prototype project, and while the initial budget is limited, we are open to negotiation based on the scope and quality of the proposed work. We are also open to discussing a simplified version if it still achieves the core dispensing functionality with RFID and keypad control. Please note that specific component lists and machine blueprints were mentioned as being in an attached document, which cannot be shared directly here. Freelancers should be prepared to work with the client to define these details.