Yup. I actually tried making an analog of electronics with water and air first. Water didn't work very well because of the high resistance. Air didn't work very well because of it's compressibility - each time it compresses and decompresses, there's serious hysteresis and you lose a ton of energy.The trickiest part to make in a mechanical version is the simplest part in electronics - the junction: Where one wire splits into two wires. I spent a lot of time trying to figure out how to do that with anything besides a fluid or a gas. Fortunately, planetary gear systems do the trick. Once I got that working, everything fell into place. Using a junction, you can easily make parallel circuits. Capacitors are just torsion springs in the spintronics model.
Sorry that HN's software rate limited your account! New accounts are subject to a few extra restrictions, and it always makes me sad when a project creator shows up and gets hit by those (I'm a mod here). That's not at all a case that we're trying to restrict!
I've marked your account legit so this will not happen to you again, and I've approved your comments that got throttled, so they're up now. Welcome to HN and congratulations on this exceedingly cool work.
seeing that nynx hinted at reversible computing, they would just be smaller and more energy efficient. The idea being that you can cram more of these in a given volume.
Reversible computing tries not to destroy information, allowing to go under Laundauer's limit [1].
When you discard the previous value held by your flip-flop, you clear the output bit, returning electrons (or a chain displacement) to the power supply. If you can instead repurpose that energy, you'll have to supply a lot less energy since you'll dissipate less. That would be reversible or adiabatic computing [2]. I have to note that processors these days are mostly power-limited, trying not to melt themselves as the energy flux inside a chip approaches that of a nuclear reactor. Just look at modern sockets and count the pins dedicated to power supply![3]
Building at the molecular scale you can achieve extremely low friction coefficients in the moving parts. Inertia also gets extremely low, and material strengths tend toward their theoretical values.
Of course electronics aren't standing still, but resistance tends to get harder to deal with as feature sizes decrease.
What I've always wondered is that wouldn't very tiny molecular mechanisms get problems with "accidental welding" since a part could be permanently destroyed by a few molecular bonds forming or breaking and (IMHO - this is my guess/assumption) such events would be likely at e.g. room temperature.
Unless designed well, yes. Parts that move relative to each other need to be designed so that unwanted bonds are unlikely to form. This generally means designing them so that unwanted bonds are less energetically favorable than the bonds they start out with. Of course, as temperature rises, the chance of breaking existing bonds rises, as does the chance of forming new unwanted bonds.
For sure - at least with the parts in their current form. A simple flip-flop takes up a minimum space of about 30 cm x 30 cm. But I wonder how small these parts could get. Like, what if spintronics was invented in the 19th century instead of the 21st century? Would Moore's law have applied to mechanical transistors?
Since I just now learned about that link, I haven't read the book to know, but I have always been interested in finding out if the ability to create smaller and smaller machines is possible by having an outer machine which manufactures an inner, smaller, copy of itself, apply the process of induction, define the termination criteria, ..., profit!
Or, maybe I'm thinking about the problem all wrong -- it's not the actual construction machinery that's the problem, it's providing the input materials to each step (gears, levers, fasteners, wiring(?), etc)
There's a Factorio-clone hiding in this problem ...
The issue is that scaling does not produce linear effects as you go down (or up) for a number of reasons. What works at the meter scale doesn’t work at the millimeter scale, which doesn’t work at the micrometer scale, etc.
So you end up having to learn an experiment at a more and more difficult to access scale to figure out how to make something actually work.
the reality is that it turned out to be easier to make things with lithography, and we don't need to pantograph our way to the bottom (whew!).
Many cell phones now have sensors that are mems-based, built using lithography (accelerometers being the best example). In many senses, we've started to achieve the goals of the book.
I did enjoy Diamond Age, maybe I should reread it! It was the first time I had ever heard of "reversible computing" and (ahem) I still don't understand it, but it's good to know such a thing exists
I'm about 175 pages into that PDF and am now sorry that I drew attention to it. I was beguiled by the name recognition and the snazzy title, but I find the text filled with hand-wavery and aspirational thinking, and it also seems to focus a lot more on DNA than I would have expected
I also find even their aspirations suspicious that any such machinery could ever possibly exist to just tweezer atoms around like marbles and voila gold from lead!
> I also find even their aspirations suspicious that any such machinery could ever possibly exist to just tweezer atoms around like marbles
We can already push atoms around with macro-scale actuators that have nano-scale accuracy (which is clumsy, to be sure), and there is little doubt that the hardware to do so will get smaller and more capable over time.
Thanks for the recommendation.
That cover though, is that topology specific to a coronavirus or do more viruses share it? Especially since the Pfizer/Biontech and Moderna vaccines deploy nano-particles for delivering their payload.
I took four years of engineering in university and work in software now, and one gif on your page made inductors click intuitively for me in a way that so many courses did not -- thank you!
In my fifties, I finally figured out that the INTEGRAL constuitive relations for inductors and capacitors were much more fundamental than the differential ones. Solved virtually all understanding problems for me.
Is there a word or a phrase for this learning phenomenon? When someone is suddenly able to fully understand a concept that has been explained to them before but, for whatever reason, they just didn’t quite “get” it?
I just pledged! My 67 year old mother got me Turing Tumble for Christmas and we worked through the first half of the puzzle book together. It was so nice to be able to explain to her what I do for a living with actual physical switches and marbles. I recommend it to everyone and anyone who will listen.
Really amazing work, well done! Having something like this when growing up would've made electronics so much more accessible.
I can't think of anyone I know close to me that would really appreciate this gift, so I'm with another comment on here that gifting it online somehow would be something I'm interested in. I'd feel happy knowing I'm supporting a great product and helping the less fortunate of the younger generation get better access to fun educational tools.
Quick question: I noticed a Form 3 in the video. How much of the prototyping did you do on it?
Also, I wish there were a pledge level where I'd buy one kit for me, and anonymously gift one to any random kid in another part of the world who wants one but can't afford it (kind of like OLPC did).
You know, I don't recommend a Form 3 except in unusual circumstances. It's labor intensive, messy, and expensive. The resin itself is expensive, but then you also have to buy expensive new resin trays frequently because they wear out fast. I used it a lot when I was finalizing the 3D models to get them ready to send off to get injection molds started. The precision of a resin printer was critical. If I were you, I'd use a service like i.materialise.com instead. The prices are low for resin prints and they're pretty fast to ship, too.
That's a great idea with the anonymous donation. If anyone is looking for a great place to donate, one really cool program is the Turing Trust. It's run by Alan Turing's great nephew, James Turing. He's awesome and he does amazing work. Here's their website: https://turingtrust.co.uk/
I'm wondering if you'd be willing to expand on why you chose this mechanical, spinning metaphor for electronics vs some other metaphor?
Most of the popular electronics books I've seen use a water or fluid metaphor to describe how components work (eg the fantastic Practical Electronics for Inventors).
Not at all intending to be critical with my question, just curious.
As a non-electrical engineer who dabbles in electronics, I'm excited for your work to help others learn and happy I can back it!
Yeah, good question. My first attempts were with fluids: water and air. Water doesn't work very well because there's a lot of resistance to flow unless the pipes are large in diameter. It's not practical for anything but the simplest of circuits. So I went with air for a long time before I realized it had no chance, either - when it compresses and decompresses, it heats and cools, and that energy is lost to the surroundings. It makes horribly inefficient circuits. It's also hard to seal moving parts without adding an unacceptable amount of friction. And finally, you still can't see air moving through a circuit.
So I stepped back and thought about how to do it mechanically. But the hardest part of a mechanical circuit is the absolute simplest part in electronics: the junction. That is, where electricity flows in one wire and splits along two wires. How do you make chain or a belt split? Not only that, but it has to follow Kirchoff's law: the sum of currents leaving the junction must equal the current entering the junction. I finally realized that's what a differential gear arrangement does, and planetary gears are a sort of differential arrangement that would work perfectly for this. It was very, very hard to make the mechanical junction so that it had low resistance while under load, but I eventually got it. Once I had that, I knew it would all work.
Seems a great idea. I did a physics degree and never 'got' electronics (Voltage, Capacitance etc) at an intuitive level in the same way that I did mechanics (Force, Mass etc).
BTW We got Turing Tumble for my son and he really enjoyed it.
