15. System integration

I´m still designing the mechanism for my final project, but I already have taken some design considerations for better integration. For the Die I made from silicone, I designed the mold with the correct dimensions to fit a PCB with the XIAO nfr52840 from which I´ll use the accelerometer:

After finishing the die, I started designing the mold. I was planning to put a XIAO nfr52840 inside the die, so I needed to be able to remove a face to insert the board. I opened a copy from my die to make some modifications.

To make the hole I measured the PCB I built for the board:

I considered a 54x24mm square so it could fit easily.

I extruded the face containing number one from the die:

The hole I made is a little over half the die´s height, so I can place the board at its center.

I measured the PCB´s height to make sure I left the right amount of space.

The XIAO fits perfectly inside the die:

The mechanism I´m going to build for the cards will be controlled with an ESP32. To do so, I´ll use a small DC motor with an encoder and a stepper motor. During week 6 I designed the PCB for the ESP32 keeping in mind the connections I would need for the motors. I also designed the PCB for the stepper motor driver. These two PCBs are designed to be connected flawlessly.

This design allowed me to connect both PCBs directly and I just needed a cable for the stepper motor which looks cleaner.

On previous weeks (week 10 and week 14) I´ve used a small DC motor with an encoder. Although I´ve successfully controlled the motor with an ESP32, The connection between the motor and the PCB is not ideal, because I use jumper wires to connect the motor to the PCB. I´m planning to use a Jst pin connector to make the connection more reliable and to look cleaner.

Messy cables

My final project is not intended to be a sold product, it´s more of a personal project which I plan to use with my brother, friends and family, so I´m not making a packaging for it, but I´m trying to make it look as good as possible and to be easy to travel with. What I´m trying to do is to make a box/base that can hold the die and the card dispenser. You can find my final project documentation here.