I’m working on 2 hardware projects right now!
Fold-up, scissor lift, cross-cantilever 3D printer for open sauce
M.2 FPGA hardware accelerator devboard
All just for fun and open source https://github.com/kaipereira :D
HN user
Munching on PCB's and hacking on hardware :D
https://kaipereira.com/
I’m working on 2 hardware projects right now!
Fold-up, scissor lift, cross-cantilever 3D printer for open sauce
M.2 FPGA hardware accelerator devboard
All just for fun and open source https://github.com/kaipereira :D
I personally love this macropad tutorial and it's how I got into doing circuit board design in highschool: https://hackpad.hackclub.com/. Before doing this, it's really helpful if they have experience messing around with breadboards, so getting them a kit can help them into a soft transition too!
I like to suggest making a macropad, then a keyboard, then going into a devboard, and then starting to make your own projects. But for kids that aren't quite in highschool yet, it can feel quite intimidating and the learning curve is moderately high, so getting them playing with breadboards first might be the best option ;)
Hack Club will also give you a grant to cover the entire cost if your kids are over 13 through their programs like stasis, fallout, or forge (you can check their site for more info)
This is insanely cool, the noise they make is also really satisfying!
What was the cost/time breakdown of the entire project because the flipdisc prices are hidden behind quotes and it seems like it would take quite a lot of time to complete the whole display!
Thanks so much!
This is so cool! I'd love to see a write-up on how made it, and what you referenced because designing neural networks always feel like a maze ;)
We ordered the PCB's and badges separately, but it's extremely easy to assemble, you just attach the eink on using the FPC connector and the badges are already in a complete setup of the hardware if you get PCBA.
You can make it more fun on yourself if you want to assemble them by hand and it's probably a bit cheaper, and JLC will ship to pretty much anywhere in the world.
Yeah the RP2040 is a bit overkill, but it's really cheap to get from JLC, easy to prototype FAST and easy if anyone wants to reference the design and create/program their own badges.
I have been looking at some other MCU's like the CH32 for future projects, so if you also have any suggestions for other ones, I'd love to hear them!
I used https://eds.st.com/antenna/#/ to get an antenna that fit with a target inductance of 4.7uH and then used https://github.com/nideri/nfc_antenna_generator to create the footprint which I slightly modified for the board! You can read a bit more about it in the journal (JOURNAL.md)!
It was really satisfying to get everything working (especially the NFC because I've found RF to be a bit tricky), but the eink logic was actually a bit of gamble, because I broke my only eink while prototyping so the production batch was the first test of the driver. So always carry spare components when designing prototypes!
So the eink holds its state once it’s programmed so you do need an initial program of the badge through USB-C, and then the NFC uses passive RF harvesting.
The total ended up being about $10/badge for 60 (5 for badge, 5 for eink), and we made the mistake of not ordering enough, so we ordered a couple more that were about $1 more expensive each. We bought all the badges from JLC and the prod files are in the repo if you want to see how much they come to in higher order quantity!
Oh wow, I've never actually heard about the Lemontron, I'll definitely take a look at it for inspiration!
I also did forget to mention, but this project is OSHWA certified too :D
Routing is honestly one of my favorite parts of making a PCB, there's something about the feeling of understanding exactly what each trace is doing that I find exhilarating.
The problem with most AI powered tools is that they don't understand the context of your board, which is absolutely crucial for routing. Like so-and-so trace could be switching really fast and an AI powered design tool wouldn't understand that and wouldn't route it properly. Or like power for example, different things have different power requirements and I feel like we're not at the point where these tools are referencing every datasheet on the planet to figure out trace/fill sizes and whatnot.
There's also some concepts I don't think these tools can wrap around quite yet. For example, minimizing loops, consistent ground planes, proper impedance control, and just all of these factors lead to an inferior board.
Not saying that humans are perfect and understand all of these too, I just feel like if you understand what's happening with your board, you can do a much better job.
At the end of the day, you'll be spending more time fixing the mistakes, which are actually pretty hard to spot without checking every single trace sometimes, then actually just routing it yourself, but maybe one day we'll get there!
I'd love to hear some other takes though ;)
I'm probably going to run Marlin just because it would be the first 3D printer I've actually made and I've heard it's more beginner friendly. I think Klipper also needs a dedicated host like a Pi which is a bit more overheard I don't want to worry about, but I'm open to exploring any type of firmware!
4 layer boards actually make it easier instead of more advanced in my opinion. You can have a dedicated ground and power plane which makes routing much simpler, and the fields are much easier to predict.
It's also just double the price, so I can get 4 layer boards for like $8 from JLC and it just makes everything much more easily.
You still do want to build up to it though, I made a macropad, then a keyboard, and then made this, so it's definitely not just an immediate jump, but I built those 2 projects within the span of a couple months!
That's a really cool idea!
I have a couple idea's on how I wanted to do it: - Belt printer fitted into a briefcase (the harbor freight case form factor would be good for that!) - Positron style - Maybe mess around with double four-bars
Making it self-contained with a battery is also a really cool concept I'll have to explore!
Hey guys, thanks for all the love :D
The website went down because of the traffic and large images, so I've temporarily switched hosting, and it should stay up now (DNS propagation might take a bit though), but I'm going to get those images smaller ASAP, thanks to everyone who posted web archives!
I'm also going to alter some of the reasoning for some of the stuff like decoupling capacitors, but the guide is still meant for complete beginners, and lots of the terminology/reasoning can be pretty overwhelming, and I still have a lot to learn about decoupling/other stuff!
I'll also add a part about what you actually need on your devboard, that's a great suggestion!
You can find a JOURNAL.md in EVERY SINGLE one of my hardware projects https://github.com/KaiPereira?tab=repositories so if you guys want to see more guides/tutorials, let me know :D