WEEK 16 - System Integration

The goal of this week was to integrate the electronic system of the final project into a physical enclosure. For this stage I designed a custom case for the PCB developed for the final project. The case was modeled in Fusion 360 and fabricated in PLA using a Bambu Lab 3D printer.

The enclosure was designed to hold the main PCB and also leave internal space for an A4988 driver and its wiring. The case includes cable exits so that the electronic system can connect to external devices without forcing or bending the cables inside the box.

The final project electronics are not only a PCB. They also include the driver stage, power and signal cables, and connections going to the external parts of the system. For this reason, the case was designed as an integration component rather than only a decorative cover.

The base of the case organizes the components, while the top cover closes the system. The design includes rounded corners to reduce sharp edges, screw holes for closing the case, and openings for cables. The internal layout separates the PCB area from the cable exit area so the wiring has a predictable path.

The first design step was to define the main dimensions of the enclosure. I used the PCB size, cable clearance and available space for the A4988 driver as references. The case footprint was planned around a rectangular electronic area with rounded corners and screw points.

The sketch included the main dimensions, internal margins, rounded corners and possible locations for holes. This helped define the relationship between the PCB, the cover, the walls and the cable exits before creating the 3D volume.

After the 2D sketches were defined, I extruded the geometry to create the 3D enclosure. The design was divided into two parts: a base for holding the electronics and a top cover for closing the system. The base includes an internal recessed area for the PCB and space for the cable exit.

The corners were rounded to make the case easier to handle and to improve printability. Screw holes were placed so the cover can be aligned with the base. A rectangular opening was added as a cable outlet, allowing the wiring from the PCB and A4988 driver to exit the enclosure.

One of the most important integration details was the cable exit. The PCB and A4988 driver require several wires, so the case needed openings large enough for cable bundles. The cable exit prevents the lid from pressing on the wires and gives the system a controlled connection point.

The base also includes internal space for the PCB and the driver. This is important because the A4988 needs room for its pin headers and wiring. The enclosure does not permanently hide the electronics; it organizes them so they can still be accessed during tests and debugging.

Once the model was ready, I exported the case for 3D printing and prepared it in Bambu Studio. The print was arranged on the build plate with the base and cover separated. The selected material was PLA because it is easy to print, dimensionally stable for this type of enclosure, and rigid enough to protect the electronics.

The final case design provides a physical structure for integrating the final project electronics. It is designed to contain the PCB, the A4988 driver and wiring, while still leaving cable exits for external connections. This makes the electronics easier to protect and organize during final project testing.

Preparing the PLA print also allowed me to evaluate the size, wall thickness, fit and accessibility of the design. This prototype can be improved later if additional mounting points, ventilation or connector openings are required after the full electronics integration.

After printing the PLA case, I tested the real placement of the final project electronics inside the enclosure. The PCB sits in the upper internal area, the Seeed Studio antenna remains connected to the XIAO ESP32C3, and the A4988 driver is positioned in the lower opening with the ribbon cables routed through the designed side exits.

This hero shot documents the system as an integrated product, not only as isolated parts. The goal was to confirm that the case could hold the PCB, allow the sensor and wiring to exit without pressure, and keep the driver accessible for connection tests during the final project assembly.

The following files include the Fusion 360 design and exported fabrication files used for the system integration case.

This week connected the electronic work of the final project with a physical enclosure. Designing the PCB is not enough for the final system; the components also need to be protected, positioned and connected in a controlled way. The PLA case helps transform the electronics from a test setup into a more integrated module.

The case still has room for iteration, especially after testing the complete wiring with the A4988 driver and final project PCB. However, this prototype already defines the size, structure and cable organization needed for the next stage of the final project.