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Ultrathin business card runs a fluid simulation

• mouse_ 1y ago
  Nice work, awesome presentation
• x187463 1y ago
  Very cool. Though, I was waiting for the video to properly 'shake' the card.
• raincole 1y ago
  Off topic, but where should one start learning writing physical simulation? Several years ago I ran into this project [0] and got overwhelmed even the algorithm can be written in 88 lines of C++. I realized that out of all CS topics, physical simulation is probably the one I knew the less (not saying I'm a compiler/database expert or something, but at least I've implemented a toy compiler and some basic data structures used in database. When it comes to physical simulation my bran just draws a blank.) [0]: https://github.com/yuanming-hu/taichi_mpm https://github.com/yuanming-hu/taichi_mpm
  • maccard 1y ago
    Rigid body simulations are much much simpler. There’s a siggraph course from 2001 [0] which is a bit of a dense read but it will bring you all the way up to a full blown rigid body simulation and understanding the math behind it too. [0] https://graphics.pixar.com/pbm2001/pdf/notesg.pdf https://graphics.pixar.com/pbm2001/pdf/notesg.pdf
    • beardyw 1y ago
      Though in this case there's not much more than 500 points, which even if you scale up is manageable.
      • maccard 1y ago
        It’s less about the number of points and scaling and more about understanding the fundamentals. Any sort of particule simulation (which is the easiest way to get into cloth, soft body and fluid dynamics) requires about the first half of that paper I linked anyway.
    • aDyslecticCrow 1y ago
      Ive done one myself. Very fun and very valuable project, with alot of optional deapth. Solar system simulation is another fun one, leaning more into nummerical differental equations solving.
  • Cthulhu_ 1y ago
    One thing that helped me was doing some tutorials for pico-8, an intentionally 'weak' game platform, one of which is a platform game with a simple / understandable inertia / gravity simulation (jumping, running left/right; think Mario). It was understandable enough with an x / y position for the character and a delta-x / delta-y representing their current speed. Every frame the dx / dy would get changed depending on player input and/or character state. Ex: if player presses jump button, set state to 'jumping' and dy to 1. Every frame, dy = dy * 0.9. When dy <= 0, set state to 'falling'. Every frame, dy = dy * 1.1 until dy = 1 (terminal velocity). Then add some collision detection. I think those basics are also behind the simpler physics simulations, the 'falling sand' types would be ideal for an application like this.
    • wizzwizz4 1y ago
      Gravity is constant acceleration (in most games). Your algorithm is broken.
  • maurits 1y ago
    For statistical mechanics, I really liked [1]. Comes with loads of python programs. To see what might peak you interest, the videos in [2] could be a good starting point. [1]: https://www.coursera.org/learn/statistical-mechanics https://www.coursera.org/learn/statistical-mechanics [2]: https://matthias-research.github.io/pages/tenMinutePhysics/index.html https://matthias-research.github.io/pages/tenMinutePhysics/i...
  • ethan_smith 1y ago
    The Nature of Code by Daniel Shiffman is an excellent entry point - it teaches fundamentals of physics simulations with clear examples in Processing/p5.js.
  • stormfather 1y ago
    Just go to Perplexity or something like that, its well trodden ground. And essentially, what you're doing is discretizing the relevant differential equations and getting that to run in a 2D or 3D cellular automaton. I'll give you a simple example. For diffusion of heat between 2 points, the rate of change (first derivative) is proportional to the difference in temp between them. So you make an update rule for points on a grid that says "calc the average difference of a cell's temp with that of its neighbors, multiply by some constant, and that is the amount to update this cell at this time. Run that for every cell in parallel, many times." Then you tack on a visualization and you can watch the heat diffuse. A fun example would be the cooling of the proto-Earth. You can watch the crust form. Heat diffusion is a good starter problem. So is gravitational interaction.
  • IIAOPSW 1y ago
    Probably what you want is "numerical methods" and "computational physics". "Physical simulation" is a very broad scope, so your code for simulating fluids is going to be very different from your code for simulating planetary orbits, and at times it may feel a bit ad hoc. But at its foundation physical laws are written in differential equations and linear algebra. So whatever algorithm lets you numerically integrate several inter-related variables is going to be broadly applicable to simulating any physical phenomena. At the simplest end of the spectrum you just naively approximate integration by brute force. Eg at each step just update your physical state variables by doing velocity += acceleration, position += velocity. This is called Euler's method, and while simple, it accumulates unacceptable errors rather quickly in most circumstance. The more advanced approach is to use a method like Runge Kutta. In circumstances where you have some known property, like say energy conservation, you can implement a method which explicitly imposes the constraint. This is good for cases where the motion is highly periodic as it prevents the numerical error from accumulating exponentially in orbits that spiral out of control. Of course at some point you'll have to grapple with the issue of if you are simulating trajectories of free particles or values of neighboring grid points in a field. This question of how best to encode physical systems and simulate them cuts to the heart of physics. I'll leave it at the old cliche "information is physical"
  • dawnofdusk 1y ago
    Essentially all physics simulations are either particle based or based on integration of differential equations (although in a computer both approaches involve a discretization which makes them somewhat computationally similar). You can consider reading through Numerical Recipes which is sort of the bible for this stuff for physicists, but it is aimed at scientific audiences with weak CS background. Something like Computer Simulation of Liquids by Allen could be a good start too. Let's be clear that the approach I'm talking about here is focused more on physical correctness: if you are a game designer it's not important that your fluid simulations are physically correct and more that it looks physically correct to a player, and there are a variety of more heuristic techniques for something like that.
  • pornel 1y ago
    For water simulation, look towards learning compute shaders. Eulerian (grid-based) simulation is one of the classic examples.
• RMDNZ 1y ago
  Amazing. Just don't show it to Patrick Bateman.
  • ducktective 1y ago
    "I can't belllieeeve RMDNZ preferred L-Johnson's card to mine"
  • tetris11 1y ago
    Practically pregnant with electric potential
  • bookofjoe 1y ago
    "Silian Rail"
• rwmj 1y ago
  Would love to see more information about how it was built. He must have worked with a company that can do the surface mount assembly?
  • Retr0id 1y ago
    You can get boards like these made for single-digit dollars per unit* even at prototype scale, through companies like jlcpcb. *I haven't looked at the specific parts for this board, the LEDs look nice and could be a little pricey.
    • rwmj 1y ago
      Boards, but can you get the pick and place and the soldering done? I wouldn't want to be soldering that many LEDs by hand!
      • mk_stjames 1y ago
        Every major chinese PCB supplier has offered very affordable PCB assembly ("PCBA") for several years now where you give the gerbers for the boards along with a BOM with part numbers from a mutual supplier catalog and p'np / solderpaste mask data and they will load up a p'np machine and oven run a small batch of boards for you. e.g.: https://jlcpcb.com/smt-assembly https://jlcpcb.com/smt-assembly https://www.pcbway.com/pcb-assembly.html https://www.pcbway.com/pcb-assembly.html
      • Retr0id 1y ago
        That price is including PCBA. Without it would be <$1/board
  • Cyan488 1y ago
    Electronics can be surprisingly easy and cheap to build these days. He designed the circuit and layout with software called KiCAD (free and open source) then submitted the designs to a fabrication house - probably a popular offshore one - that easily can handle that level of board and component placement complexity. It would probably cost only a few hundred to build and ship, with 1 month turnaround time. You can also hand-assemble surface mount parts by applying solder paste carefully to the pads, then placing all the components on the paste and heating the board until all the solder melts. That would have very time consuming for all those LEDs!
• ChrisMarshallNY 1y ago
  Very nice, but probably a bit too expensive to just hand out. I knew a chap that had a similar hardware business card (I don't remember exactly what it did, but it wasn't as cool as this one). I remember that his card was pretty scuffed up, and he insisted I give it back, after he handed it to me. Bit weird.
  • Cthulhu_ 1y ago
    How much does it cost? The guest passes for hacker conferences are full-on computers these days, if this is in the same price bracket it would be a great idea for those.
    • 4gotunameagain 1y ago
      There's a BOM, you can find out. Plus some peanuts for the PCB :) Now whether you get it populated or not.. https://github.com/Nicholas-L-Johnson/flip-card/blob/main/kicad-pcb/Production%20files/flip-card_BOM_purchase.csv https://github.com/Nicholas-L-Johnson/flip-card/blob/main/ki...
      • unwind 1y ago
        Just as a point of interest perhaps for folks who are not familiar with PCB design and modern electronics: the "huge" matrix of 21x21=441 LEDs would, with the specified LED from the bill of materials (BOM) cost all of $6. That is based on the price for low quantity (1-500 pieces) though; if you were to build more than one board you would buy more LEDs, pushing the per-LED price (way) down. You can get 4,000 LEDs for $30.' Edit: here is the LED in question, from the BOM [1]. [1]: https://jlcpcb.com/partdetail/C497920 https://jlcpcb.com/partdetail/C497920
    • whartung 1y ago
      I don't know, I struggle with a light switch, but that doesn't look like board someone took home with a box of parts and a soldering iron to make at home. Are there services that you can send the BOM and board files too, and not only do you get the PC board back, but it's populated? Will they do that for a onesy-twosy thing like this? Then all you have to do is supply the battery and download the firmware (however that is done).
• DonHopkins 1y ago
  Instead of a business card, I'd love an ultrathin pleasure card you can refill with virtual beer and virtually drink! You could input your weight, and it could track you BAC! I made "PalmJoint", a beamable Palm pleasure card for CodeCon 2002, when everybody was beaming their contacts around by IR at conferences, I would beam an interactive doobie simulator a bunch of people could play together in a circle. Each person gets their own doobie, and you can have contests to see who can virtually smoke theirs the quickest, or keep it lit for the longest time. I never get around to implementing an IR token passing network: https://donhopkins.com/home/images/PalmJoint.png https://donhopkins.com/home/images/PalmJoint.png https://donhopkins.com/home/PalmJoint/Src/PalmJointMain.cpp https://donhopkins.com/home/PalmJoint/Src/PalmJointMain.cpp Some conferences of the era had kiosks with IR LEDs that beamed out a Palm app with a conference map and schedule, which would have been great to hijack for beaming out PalmJoints instead.
  • serf 1y ago
    small ad-hoc networks like that with IR and early bluetooth were a lot of fun.
    • DonHopkins 1y ago
      For beaming a lit joint around, you would definitely need an acknowledgement that it was safely passed, lest it drop on the floor! But how would you prevent duplication if several people received the same joint? I'd just mark that bug "Intended Feature: Will Not Fix." The Bluetooth Bong was a vast improvement over the MIDI Bong. MIDI aftertouch on the carburetor was a nice improvement over your grandfather's old Serial Acoustic 300 Baud ASCII Bong, but the Bluetooth Bong HID has a much higher bandwidth, multitouch chording, accelerometer tilt tracking, modular monophonic splash resistant microphone, and they weren't as easy to accidentally knock over because they were wireless. An extremely important feature if you have cats around. But nothing beats a high-end spill-proof Rooᴙ 802.11be NVB (Network Video Bong) with fully submersible IPX8 smoke resistant stereo mics.
  • Cthulhu_ 1y ago
    I love it; I bought a secondhand Palm just before smartphones became a thing for cheap and had a lot of fun with it. I wonder if I still have it somewhere and whether it still works, I haven't seen it in ages though so probably not.
• QuiCasseRien 1y ago
  I love when people don't have to talk to explain how the hell they are expert in a domain. This is a very good example, nice work !
• 5- 1y ago
  i absolutely love the form factor! a similar one was beamu (eink screen, nrf52 with bt): https://nicgardner.com/2020/05/09/beamu-first-impressions/ https://nicgardner.com/2020/05/09/beamu-first-impressions/ (this was an actual product, if a bit pointless. i have one still) any others?
  • TechDebtDevin 1y ago
    Do you use any of the features? This is kinda cool, I love when people pack way too many features into a single product :P
    • 5- 1y ago
      didn't really buy it for the advertised features, although networked tic-tac-toe works fine. :-)
  • abdullahkhalids 1y ago
    This is so cool. I wish something like this had the ability to load your debit/credit cards into it. Advantages over using the card directly or a wallet app on your phone. 1. You don't voluntarily give your financial transaction info to big tech. 2. Your card details are hidden. So if your wallet gets stolen, less danger of fraudulent transactions. 3. Carry one heavy card instead of many light ones. 4. Don't have to memorize the pin of all the cards. Or the pin just shows on the mini screen after finger print authentication.
• OisinMoran 1y ago
  If you like this, you'll also love Mitxela's fluid simulation pendant [0], and likely all of his work! I'm consistently astounded by how informative and enjoyable his stuff his. He shares so much, so freely and it's so well produced, with a lovely voice to boot. Inspirational! Watch his vids, read his write-ups or both! We need more people like this. [0] https://mitxela.com/projects/fluid-pendant https://mitxela.com/projects/fluid-pendant
  • nirava 1y ago
    +1 for mitxela, dude never ceases to amaze
  • msephton 1y ago
    The circle works much better for the fluid simulation.
    • mananaysiempre 1y ago
      And now I can’t stop thinking about those circular LCDs and OLEDs they sell in China as (evidently if unofficially) devboards for not-overly-smart watches, thermostats and such.
      • msephton 1y ago
        I bought one recently and none of the provided code samples would compile. Zero support.
  • unwind 1y ago
    That was very clearly mentioned and linked in the article, too.
    • OisinMoran 1y ago
      Ahh, today it is my turn to fail the online reading comprehension test! My bad, I'm just very into Mitxela.
    • 1y ago
• fidotron 1y ago
  The typical Chinese sources have been selling "digital hourglass" type ornaments that work like this for a while. There was a whole game based on this sort of thing back on the Acorn Archimedes: Cataclysm https://www.youtube.com/watch?v=3Byyz1Vlv8w https://www.youtube.com/watch?v=3Byyz1Vlv8w It got remade for the 360, but the original was regarded at the time as surprisingly impressive for the machines it was running on.
  • DonHopkins 1y ago
    Is there a Digital Disco Ball?
    • fidotron 1y ago
      You could make a bad analogue of such a thing using WLED - although as many people have observed it has a tendency of turning anything anywhere into looking like a vape shop. The problem is so much of the effect of a disco ball is irregular directional beams reflecting off it, which would be hard to do.
    • bookofjoe 1y ago
      https://www.amazon.com/LED-Disco-Ball-NuLights-Lighting/dp/B019KYVVSQ/ref=sr_1_1_sspa?crid=VMYD9I1Q8VG5&dib=eyJ2IjoiMSJ9.eT7JXZQ95pI9x0gc_GpJm0IM0os3Ep2ozVCAEeuVqbQB5TN58hRenQGJGAYDSBPUrocxjMGugh4UPOvk6DELrLI0hQh1joe7L122pID-tRHgv9i7oYKj5c8TdmdkfgFu189Lj_lSKsSWe3ANFP3j23bvg_mo5OeFlH2AUX-Ijejcn9TukkcT3Gmp41L5j-rtc0OvOYdZGZeWgxV_ltQlgA7fFQA0ZYYE-iFudJd-8QZQ06pxY5oelQKIfBrAESk2_4z5LYl-KUNt7h9k1LFquG-z02AVLUCsf73NwF428lU.VW188K2nm3PYN-jkYVt90vUk0pZVOs1mZLArB65lKV4&dib_tag=se&keywords=Digital+Disco+Ball&qid=1754668419&sprefix=digital+disco+ball%2Caps%2C127&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1 https://www.amazon.com/LED-Disco-Ball-NuLights-Lighting/dp/B... https://www.youtube.com/shorts/E8rzln1gUBg https://www.youtube.com/shorts/E8rzln1gUBg
  • DonHopkins 1y ago
    Wow what a cool retro fluid simulation game! Oxygen Not Included simulates a whole bunch of different kinds of fluids and gasses, and has a sandbox mode and debug tools. I love using it as a kidpix-like painting tool, just to see how all the different materials interact. https://youtu.be/U0MevBWyfS8?t=295 https://youtu.be/U0MevBWyfS8?t=295
• gcapu 1y ago
  Amazing project, but the font on the back of the card is gross.
  • Nevermark 1y ago
    That’s cred, man. Real cred. Wack font. Circuits exposed. Pixels with fat borders between them. An ugly charging port. But more stuff, packed into a small sleek volume than reasonably possible. Working perfectly. That’s not Jobs. Oh, no. It’s effing Woz. The guy is a true hardware engineer.
    • gcapu 1y ago
      For the most part I agree, but the purpose of a business card is to be read. You can barely read that text.
      • phirks 1y ago
        The render is pretty gnarly, but it's not quite that bad in person https://github.com/Nicholas-L-Johnson/flip-card/blob/main/media/IMG_20250808_102256109_AE.jpg https://github.com/Nicholas-L-Johnson/flip-card/blob/main/me...
        • gcapu 1y ago
          The card is so impressive that it doesn’t matter much, but I think that if you remove half of the text in that card and make it very legible it would burn your name into people’s brain.
          • Nevermark 1y ago
            The card should not have any text on it, but show his info on the screen when the card is first shaken, and after it has been held still for 4 seconds, before going to sleep after another 10 seconds of no motion.
    • denysvitali 1y ago
• throawayonthe 1y ago
  that's awesome, but i think since it's a business card the text on the back should be more legible (nicer font and/or bigger)
  • stusmall 1y ago
    Agreed. I'd never hire this embedded system engineer to do graphic design. /s
• AndyTyler 1y ago
  [dead]
• phkahler 1y ago
  It would be cool to have a USB C connector that goes through the PCB so total height is that of the connector and not board+connector. Like this one: https://www.adafruit.com/product/5180?srsltid=AfmBOopEIapZEqfFTxUsoX02bEBbWx0gSi_2OUS6NVuizp8iHXYdeLneqZI&gQT=1 https://www.adafruit.com/product/5180?srsltid=AfmBOopEIapZEq... But with supports along the sides that could solder one the top and/or bottom of the PCB. You'd have a notch cut out for the connector.
  • throawayonthe 1y ago
    It is. rather it's even smaller, it simply has the inner part of a usb c connector - exactly the thickness of the pcb similar to https://github.com/cnlohr/ch32v003_3digit_lcd_usb/ https://github.com/cnlohr/ch32v003_3digit_lcd_usb/
  • ciaranmca 1y ago
    Thought the same but from what I can see those are somewhat uncommon, presumably you are unable to affix them to the board as securely as the typical connectors
  • echelon_musk 1y ago
    The images in the GitHub show that the card has this.
  • cameron_b 1y ago
    In the implementation, the design uses a 'card edge' type connector with the whole PCB fitting into the constraint of the thickness of the center blade of the USB-C connector. So when charging, the board slots into the cable-end connector, and when not charging there is only the PCB. The PCB has cut-outs for the cable-end connector to fit into the PCB -- so like you're saying, but even thinner.
• kuschkufan 1y ago
  Impressive, very nice. Let's see Paul Allen's card!
• mrcwinn 1y ago
  This beats the Bateman card. Excellent work!
  • latexr 1y ago
    But does it beat the Joel Bauer business card? It took 25 years to design! https://youtube.com/watch?v=4YBxeDN4tbk https://youtube.com/watch?v=4YBxeDN4tbk
• donohoe 1y ago
  If they used a sans-serif font then they would have nailed it
  • bschwindHN 1y ago
    That and the overlapping silkscreen hurt to see, but otherwise a super cool project. Although they're very minor things that don't technically matter, it can give off certain impressions to people.
    • queuebert 1y ago
      Not nearly as tasteful as Paul Allen's card.
  • xp84 1y ago
    disagree, a nice serif font is more distinctive with most of everything using a very tight cluster of boring sans-serif fonts.
    • donohoe 1y ago
      In that case I will add that this particular serif font was also a poor choice out of the variety of serif fonts out there.
  • tiagod 1y ago
    I sort of like it. Looks like a Neon Genesis Evangelion episode card
• NoSalt 1y ago
  We getting our stories from Reddit now?
  • augergine 1y ago
    You’re going to get downvoted obviously but this appeared on Embedded (or electronics?) and then made its way here. It’s a bit telling the actual hacking communities are on “that awful site” that’s so beneath us, meanwhile our pristine HN is full of gushing AI ads as front page hacker material.
    • NoSalt 1y ago
      I only mention this because this was posted here at, approximately, 08:00 EST 2028-08-08, and posted on Reddit at, approximately, 00:00 EST 2028-08-08.
      • augergine 1y ago
        They’d rather post there than here. https://www.reddit.com/r/embedded/comments/1mkkd4z/my_business_card_runs_a_fluid_simulation/ https://www.reddit.com/r/embedded/comments/1mkkd4z/my_busine...
        • phirks 1y ago
          [dead]
• uticus 1y ago
  No issues mentioned with battery being exposed on both terminals? Seems like easy short hazard.
  • MobiusHorizons 1y ago
    Is a cr2032 shorting it is not dangerous, it can’t supply the current to get hot enough do any real damage.
    • uticus 1y ago
      It says rechargeable, maybe a CR2032 size but prob lithium chemistry. Even a small size could create quite a hazard if shorted.
      • AnotherGoodName 1y ago
        The C in CR2032 means lithium fwiw. As in it's lithium either way. The LiR2032 (rechargable lithium) are slightly higher voltages but pretty much the same total energy. Fwiw if you ever have electronics that require 3V minimums the LiR2023 is better than the CR2032 since it's 3.7V vs 3V in the same form factor. It's common knowledge that the ESP32 for example can glitch on a CR2023 since it needs 3V minimum but it'll actually run fine on a LiR2032.
      • MobiusHorizons 1y ago
        Yep, the rechargeables of this form factor are also pretty safe. They just don’t have much current capacity, as they are meant for long life (years) and long current draw.
• deleted 1y ago
  [deleted]
• bookofjoe 1y ago
  State of the art in 2009: https://www.tokyoartsandspace.jp/en/creator/index/B/124.html https://www.tokyoartsandspace.jp/en/creator/index/B/124.html
• moechofe 1y ago
  This will finish in the trash at some point like any other business card, but, good job.
• Kapura 1y ago
  point of order: these are thicker than normal business cards.
  • deleted 1y ago
    [deleted]
• snickerdoodle12 1y ago
  [flagged]
  • FinnKuhn 1y ago
    To be fair it fits in with the Github and LinkedIn links.
  • denysvitali 1y ago
    He's an hardware engineer, not a software engineer. After many years of self-hosting an email server I also came to the realization that it's not worth the hassle (in terms of maintenance / problems) and I switched to Proton Mail. Using a custom domain with Proton Mail is not free (and all the other alternatives I know of are the same) and there's little advantage other than having a nice name. I think for a HW Engineer this is good enough.
    • snickerdoodle12 1y ago
      I wouldn't recommend self-hosting email to anyone, but the expense of paying Proton Mail is absolutely worth the peace of mind (you are in control of your email & can effortlessly switch email providers) and professional appearance. We're talking about someone handing out $17/ea business cards here.
• cvsv 1y ago
  I was expecting a regular business card where the paper was so thin it flowed like fluid.
• wkat4242 1y ago
  > One of the more difficult features was the rechargable battery. Flat ones do exist. I have one eink TOTP card that's no thicker than a normal credit card. And also an airtag style tracker that's about twice as thick. Maybe it uses the same kind of battery.
  • bookofjoe 1y ago
    O.4mm thick rechargeable battery: https://www.lithium-polymer-battery.net/ultra-thin-lithium-polymer-battery/ https://www.lithium-polymer-battery.net/ultra-thin-lithium-p... Standard credit card: 0.76mm thick
  • uticus 1y ago
    seems dangerous to have terminals of battery exposed, shorting (and with rechargeable, burning) hazard
    • spacedcowboy 1y ago
      Some conformal coating spray would probably be all that’s needed.
• physicsguy 1y ago
  I like this one: https://michaeldriver.co.uk/The-Business-car-d-1 https://michaeldriver.co.uk/The-Business-car-d-1
• nabilt 1y ago
  For those that want more details on how the software works, this guy goes into a bit more detail for his version Fluid simulation pendant https://mitxela.com/projects/fluid-pendant https://mitxela.com/projects/fluid-pendant https://www.youtube.com/watch?v=jis1MC5Tm8k https://www.youtube.com/watch?v=jis1MC5Tm8k
• dmitrygr 1y ago
  One note for the readers here: an electronic business card has a VERY LARGE effect on those you give it to. More than I expected when I made mine. It is surprisingly effective. Even if the BOM is $30, it'll pay for itself in the ease it adds to a job hunt easily
• msarnoff 1y ago
  Surprise no one's mentioned yet that the firmware is written in Rust. As someone who's struggled with getting started with embedded Rust (the landscape seems to be changing quite a lot?) it looks like a good example. Also it's a bit startling to see floating-point code used so freely. Shows how rapidly the capabilities of MCUs have developed. 15 years ago, doing floating point on a microcontroller would be unspeakable /s
  • Jweb_Guru 1y ago
    Yeah embassy has improved tons recently. This is because embedded Rust is receiving a lot of investment from industry, embedded engineers desperately want a real C alternative there.
• deleted 1y ago
  [deleted]
• bookofjoe 1y ago
  Interview with the maker:https://usesthis.com/interviews/tim.jacobs/ https://usesthis.com/interviews/tim.jacobs/
  • phirks 1y ago
    That's actually not the same guy. He made the pendant that this project is based on.
  • bookofjoe 1y ago
    My bad: "That's actually not the same guy. He made the pendant that this project is based on." THANK YOU phirks for the correction. Much appreciated.
• SequoiaHope 1y ago
  Beautiful design! I want to say as a maybe helpful review point that I see overlapping silk in a few spots. Ideally it would be nice to clean that up, possibly removing all designators which for my personal preference would work, but some people might like to see those. Also I would choose a more playful font for the back text but I like playful. This is an excellent project, nicely done! I’m doing a lot of RP2350 LED work right now, I’ll have to see if I can run your code on the pendant I am designing.
• W3zzy 1y ago
  It's not white, it's bone.
  • thrance 1y ago
    Now, let's see Paul Allen's ultrathin business card that runs a fluid simulation.
    • deleted 1y ago
      [deleted]
• _Microft 1y ago
  If you are curious what PCB designs or schematics look like, you can use an online viewer for KiCad files to find out yourself: https://kicanvas.org/?github=https%3A%2F%2Fgithub.com%2FNicholas-L-Johnson%2Fflip-card%2Ftree%2Fmain%2Fkicad-pcb https://kicanvas.org/?github=https%3A%2F%2Fgithub.com%2FNich... @creator of the card (phirks?): have you considered further interactivity or maybe using the LED matrix for showing text or other information? You could use touch buttons for control as they basically add nothing to the BOM? Edit: this is of course really awesome as it is
  • phirks 1y ago
    I was thinking of throwing in a game like Tetris with just accelerometer controls. That'll be after I find a job though. Numbers were actually the first things I displayed, I actually still have all the code to display them still sitting unused. Text has been less of a success. Having the letters be easily legible takes more space than I would have thought, and the small pixel fonts don't look great with the big spacing between the LEDs. Maybe some scrolling text would look good, but I haven't focused on it too much. I tried getting a QR code displayed, but it didn't want to scan. For buttons, I'm kind of married to the idea of no buttons. The accelerometer does recognize clicks and double clicks in different directions, so that might be useful for something. I encourage anyone who wants to fork/contribute/post issues on this to do so and I'll try to be a good maintainer.
    • _Microft 1y ago
      Thanks for the detailed reply. I actually like the idea of using the accelerometer as input device and the design choice of using no buttons. What’s the update rate of the LED matrix if I may ask? Maybe the combination of an accelerometer and the LEDs lends itself to a persistence of vision display?
    • echelon 1y ago
      > That'll be after I find a job though. I can't imagine you'll be on the job market for long (and I certainly hope not). This is such an amazing looking for work ad, I'd imagine you'll get snapped right up. Major kudos on this. It's amazing!
• delichon 1y ago
  Advantages of a business card sized hollow box partially filled with water: * more realistic fluid motion * cheaper, easier build * easier to debug Disadvantages: * risk of wet butt when you sit down * less joy of doing hard things
  • kazinator 1y ago
    Disadvantages: * excessively fast fluid motion at card scale
    • N2yhWNXQN3k9 1y ago
      increase viscosity of said fluid
      • kazinator 1y ago
        It doesn't work that way, unfortunately. The virtual fluid represented by the LEDs does not move anything like syrup. It's like looking at a small image of water sloshing in a big tank. To get of fluid to behave that way on the scale of several inches, the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced.
        • deleted 1y ago
          [deleted]
        • bullox 1y ago
          > the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced. /joy of doing hard things intensifies
        • wedesoft 1y ago
          You can use two different fluids instead of water and air.
        • N2yhWNXQN3k9 1y ago
• techlatest_net 1y ago
  [dead]
• wvlia5 1y ago
  they should've added this card in that American Psycho scene
• modeless 1y ago
  > board edge usb-c port This is awesome. I bet we see a lot of these in the future once people realize it's possible to have a USB-C port on your board with no extra parts and zero soldering.
  • lbourdages 1y ago
    That must be very fragile! Gotta be careful when unplugging, pulling very straight.
  • noveltyaccount 1y ago
    I thought this was one of the most impressive parts of the design, had no idea this was possible.
• phirks 1y ago
  >Amazing project, but the font on the back of the card is gross. >It sort of reminds me of those research professors that have received multiple awards and their website is an unstyled HTML page with 4 links >If they used a sans-serif font then they would have nailed it >this particular serif font was also a poor choice out of the variety of serif fonts out there >that's awesome, but i think since it's a business card the text on the back should be more legible (nicer font and/or bigger) Ok, for real though, can someone just tell me what font to use? We can all see this isn't my strong suit and now you're in my head.
  • Inityx 1y ago
    My defaults are sans-serif Helvetica or Roboto, serif Roboto Serif, and monospace Fira Code
    • N2yhWNXQN3k9 1y ago
      swoons
  • wavemode 1y ago
    You should see the font on Paul Allen's card.
  • strogonoff 1y ago
    A few business card typography tips off the top of my head: — White on black (inverse) is less legible, so all else equal compared with black on white the font should be bolder and/or bigger for equivalent readability. (Using caps or small caps is also OK in display text like titles, if it reads easier.) — Legibility is also impaired by visual noise around the text (it’s not a single color but there is some pattern, for example). Compensate for that, too. — Unless you really know what you are doing, stick to one font. You can use bolder/lighter variants of the same font. — Never compress fonts vertically or horizontally. Instead, pick a different font. Many fonts have condensed/compressed alternatives, or there is also Impact if you want it. — Use white space. Padding lets it breathe. — Use typographic features. Em dashes (separate them by thin spaces), bullets. > Embedded Design⠀⠀⠀Hardware ∙ Firmware or > Embedded Design — Hardware, Firmware vs. > Embedded Design - Hardware/Firmware That said, everything except the first two is subjective. A relaxed vibe of “don’t give a damn about it” might be strategic if you are good at what you do (and crucially it is not design), as long as your card is legible and does its function.
• thrown-0825 1y ago
  Awesome project, but why is this considered “ultrathin”? I would think a business card that is as thick as a usbc port + pcb would be considered pretty thick.
  • cortesoft 1y ago
    It's not as thick as a usbc port, look at the picture of them charging... the usb plug is much thicker than the card.
    • thrown-0825 1y ago
      ah I see, its still several times thicker than a business card though. so is it ultrathin relative to a phone?
• pornel 1y ago
  The simple box-shaped container and low framerate/low gravity simulation doesn't show off what the FLIP algorithm can do. The algorithm is a more expensive combination of two simulation methods to support both splashes and incompressibility, but the benefits are barely visible in the simple container.
• m00dy 1y ago
  lol, if you look at the firmware, it is essentially a bunch of if-else statements, rather than very complex simulation code.
  • phirks 1y ago
    The fluid simulation logic is split into a separate crate. https://github.com/Nicholas-L-Johnson/flip-card/tree/main/fluid_sim_crate https://github.com/Nicholas-L-Johnson/flip-card/tree/main/fl...
• 404human 1y ago
  Cool toy or business card? Either way, it’s unforgettable.
• mightysashiman 1y ago
  Any way to buy one maybe?