System Integration

During this week all the individual developments completed throughout Fab Academy were integrated into a single functional system. The objective was to combine mechanical design, electronics production, embedded programming, interface development, sensing, and output devices into the final PrintVault Pro prototype.

PrintVault Pro is a controlled environment designed to improve the reliability of 3D printing by maintaining stable environmental conditions. The system continuously monitors temperature and humidity while controlling internal heating and ventilation.

This week represented the transition from isolated subsystems to a complete product capable of operating as a single integrated machine.

Before beginning assembly, a complete system architecture was developed to define the relationship between all hardware components. The enclosure contains sensing, processing, visualization, heating, ventilation and monitoring systems connected to a central controller board.

The architecture was designed around a custom PCB developed during the Electronics Design and Electronics Production assignments. This board acts as the central hub that communicates with sensors and output devices.

The final enclosure integrates multiple subsystems that were individually developed throughout the Fab Academy process.

The enclosure structure was designed to provide a thermally controlled environment while maintaining visibility of the printing process.

The body of the enclosure was designed using galvanized steel panels due to their rigidity, durability and resistance to elevated temperatures.

According to the design sketch, the enclosure consists of:

• Galvanized steel body panels
• Galvanized steel top cover
• Galvanized steel bottom panel
• Two transparent acrylic doors

Acrylic doors were selected to allow visual inspection of the printer while maintaining thermal isolation.

The enclosure dimensions were established around the size of the 3D printer and future electronic components while maintaining sufficient internal airflow.

The custom PCB serves as the central electronic controller for the entire system. All sensors, displays and actuators are connected directly to this board.

The board integrates:

• XIAO ESP32-S3 microcontroller
• SHT31 temperature and humidity sensor
• OLED display
• Fan and heater control outputs (MOSFET drivers)
• Power regulation circuitry
• User input buttons

This centralized architecture simplifies wiring and reduces the number of independent modules required inside the enclosure.

Housing the three PCBs

The electronics of PrintVault Pro are split across three separate PCBs. To keep them organized and protected, all three boards were mounted together inside a single 3D-printed box. Grouping them in one enclosure keeps the electronics compartment tidy, protects the boards from dust and accidental contact, and makes the whole electronics module easy to remove or service as one unit instead of three loose boards.

Initial wiring idea

My first plan was to place the PCB box on top of the enclosure. On paper this kept the boards accessible, but when I started routing the connections I realized the wiring would be spread out and very visible: cables coming from the sensor, the fan, the heater and the display would all have to travel up to the top of the enclosure, crossing the front and the sides. The result looked messy and exposed the wiring exactly where the user looks at the machine.

Final wiring solution

To fix this, I moved the PCB box to the back of the enclosure. Placing the boards behind the machine means the cabling runs along the rear panel instead of across the front, so the wiring is hidden from the front view and the machine looks much cleaner. The connections to each component became shorter and more direct, and the front of the enclosure now shows only the doors and the print, with no visible cable clutter.

Environmental conditions are continuously monitored using an SHT31 digital sensor.

The sensor provides:

• Temperature measurements
• Relative humidity measurements

Data is transmitted through the I²C communication protocol to the XIAO ESP32-S3 controller.

The measured values are displayed locally on the OLED screen and can also be transmitted to the remote monitoring interface.

Two main actuators are responsible for controlling the internal environment:

• Heating element
• Exhaust fan

The heater increases the internal temperature when necessary, while the fan removes hot air to prevent overheating.

The control logic is based on sensor measurements, using hysteresis control around a per-material setpoint to keep the chamber temperature stable without rapid on/off switching.

A Raspberry Pi 5 equipped with a camera module is integrated into the enclosure for real-time monitoring of the printing process.

The Raspberry Pi serves several purposes:

• Remote video streaming
• Print monitoring
• AI-based failure detection
• Remote user interaction

The camera is positioned to observe the print area and provide continuous visual feedback through the desktop interface.

The monitoring dashboard developed during Week 14 acts as the primary user interface for the enclosure.

Through this application the user can:

• Monitor temperature
• Monitor humidity
• View live camera feed
• Control heating
• Control ventilation
• Activate emergency stop functions

The interface centralizes all system information into a single control panel, improving usability and enabling future remote access.

The entire enclosure is powered through a 12V power supply connected to the AC mains.

This supply distributes energy to:

• Electronic controller board
• Cooling fan
• Heating element
• Display system
• Additional peripherals

A dedicated power switch was incorporated to provide safe startup and shutdown procedures.