Creating the chassis and adding to CAD Pt. 2
so today i worked on adding making my CAD design look better and i also added rail / supports that will hold in the PCB so i doesn’t move which im also going to extend this to hold the screen later, added the USB-C hole and button holes
then i went into fusion 360 and i started to create my chassis, i started all over again even though last time i only had a box, i wanted to use sketches this time because it would be easier and it felt better starting off again.
first i added the supports, i went with this design where half the supports are connected to the bottom and the other half is connected to the top that way the PCB can just kinda snug in there, next i just added a opening so that the usb port would fit, then a added in my PCB so i could see if everything lined up which it did so im very thank full for that
next i added the button holes, i was kinda freaking out about this because i thought that the supports would interfere with my buttons, but if you look at the photos there is only minor inter lap which i didn’t even account for when making them so it was pure luck that this happened
now the real challenge will be creating the actually buttons because i don’t how how to make them to where they wont get stuck on stuff or how to distribute the pressure of the press all around the button because i don’t know if you can see but the button component on the PCB is a bit under the center of the button on the case, so my main worry is about hitting the button component and the button like tilting and getting stuck or not being able to come back to its unpressed position, if you understand what im saying. if you made it this far and have any ideas i would appreciate
after i finish this i was thinking about also adding a slimmer version, but that might have less features than the planned second version i tend to create because when looking at my Case in fusion 360 i realized how much space i am wasting so i dont know.
Redesigning CAD + Started creating case Pt. 1
Today i decided to work on making my CAD design better because the first every version looked really bad, didn’t have all the angles and measurements i needed to actually make this device.
In this new version there will be more drawing for stuff like how all the components will fit inside the chassis - how they stack on top of each other so i can see how much room i will have.
I don’t have a picture of the chassis i made in this journal because it was literally just a box but ill probably add a photo of it in the next part
I decided to make the USB-C breakout board is was using on my PCB in my CAD design so i could make my design more accurate without guessing, this probably took the most time out of my day i kept entering the wrong numbers so i had to redo it a lot and had to keep looking back
when i first added my chassis into fusion 360 i realized that it was to small because i didn’t really account for walls because in Auto Cad they are only lines they dont have thicknesses, so i decided to make two models one where i added a 1mm thickness to the wall going into the device which would make the inside smaller which didn’t work so i decided to go with my second where i just added 1mm all around the outside, im really counting on being able to order it in aluminum or something a little stronger but now thinking about it i might add a extra 0.5mm onto it
Starting the PCB — Added the Display and Replaced USB-C
today i started working on the PCB. First i added all of my footprints and assigned them to their components. at first i didn’t have the display datasheet yet, so i just placed everything without thinking about the display components because I didn’t know how big the connector I needed was going to be
I was originally going to start routing today starting with the USB-C connector but the D+ and D− data lines on it were so incredibly frustrating that i decided to switch it for a different component. I also wasn’t very confident that I could solder the previous USB-C component so I replaced it with a Adafruit USB-C breakout board.
After that i contacted the display manufacturer and asked them to send me the display’s datasheet so I could figure out which connector i needed. Once i got the datasheet i added the display connector and a backlight driver to my schematic.
i still haven’t positioned the display connector or any of its supporting components on the PCB yet which is why the attached image looks a little messy. I plan to work on placing those components tomorrow.
Partially Completed Schematic
Today I started designing the schematic for Artifact by finding and choosing the main components I wanted to use.
For the microcontroller, I chose the STM32U585 because it has good USB support, plenty of memory, and a lot of GPIO pins for the hardware I already have planned and anything else I might add later.
For the security chip, I chose the ATECC608C. It will help protect the encryption keys used for passwords, accounts, and other important information.
For external storage, I chose the W25Q128 flash memory chip. It will be used to store account information, and it also uses less power than something like an SD card. I wanted to keep power usage in mind in case I decide to add a battery later.
For the buttons, I chose the EVQ-P7 because they are small and should work well as side mounted buttons.
For the USB-C connector, I picked one that looks similar to the connector on the YubiKey 5. I chose it because it looked familiar and matched what I imagined Artifact would look like. Those are most of the main components I have chosen so far.
One problem I had was importing the component symbols into KiCad. I was originally using KiCad 10.0, and it would say the libraries imported correctly, but they were actually silently failing and I could not use them. I ended up switching to KiCad 9.0.4, which fixed the problem.Right now, the schematic does not have a display because I am still waiting for the manufacturer to send me the files I need.
Finished the V1 Sketch using AutoCad
I worked on my first sketch of my hardware project called artifact, the design is based of a image i had in my head of what i wanted it to look like. i wanted to go for a usb stick look with usb-c(which is in yellow) and then having buttons on top(orange) that can be used to could be used to control the interface, right when i started this project i looked for the screen(purple) i would be using right away because i wanted to base my case and overall dimensions on it so that later on my pcb and all that wouldn’t be to big, i chose to make it 14mm tall so that later on i would have enough room for a battery, my pcb and anything else i might have to add because im still trying to find all my parts, overall its a little bigger than a regular usb but i think it will be fine, the only thing im worried about is the weight because i dont know if it will be able to stay connected to the usbc port when connected to a phone or pc
