jayyhu 6 hours ago

Reading the article, it looks like so far they only have a working resettable fuse (a passive device), and only hypothesize that a transistor was possible with the copper-infused PLA filament. So no actual working active electronics.

And from the paper linked in the article[1], it seems the actual breakthrough is the discovery that copper-infused PLA filament exhibits a PTC-effect, which is noteworthy, but definitely not "3D-Printed Active Electronics" newsworthy.

[1] https://www.tandfonline.com/doi/full/10.1080/17452759.2024.2...

  • IanCal 42 minutes ago

    Hang on, can you explain why this is passive and not active?

    > Harnessing the described phenomenon, we created the first semiconductor-free active electronic devices fully 3D printed via material extrusion. We demonstrate this breakthrough through the implementation of monolithically 3D-printed logic gates.

  • bee_rider 31 minutes ago

    Well, it is just “a step.”

    Whether or not it is newsworthy… eh, I mean, what is MIT News? A campus newspaper? I’m pretty sure we had articles on particularly big games of capture the flag in mine.

  • hatsunearu an hour ago

    usually even these academia hype pieces have some grain of utility but this one was so incomprehensibly bad that i was genuinely confused if i'm reading it incorrectly. what the hell?

  • greenavocado 2 hours ago

    > So no actual working active electronics.

    Oh so this is another scam like the MIT Food Computer. At this point I assume everything coming out of MIT is a scam until independently validated by disinterested third parties

LASR 13 minutes ago

I am a fan of 3D printing. And I think you can probably get some circuit traces 3D printed for some niche applications.

But active electronics? That's a huge stretch. But more importantly, the economics just doesn't make sense. Components already cost fractions of a cent. Small-run PCB prototyping is like <$25 for 5 boards or so.

"A step toward..."

Maybe. But why?

reader9274 2 hours ago

This is like posting "Landing on Mars" and all you did was catch a reusable rocket.

  • cladopa 6 minutes ago

    "all you did was making rockets 10x cheaper", so you have plans for making them 100x to 1000x? That has nothing to do with Mars!

  • dools an hour ago

    I think the "step towards being an inter planetary species" as a result of catching a re-usable rocket might have merit in that it makes construction of things in outer space easier (although that's probably a charitable interpretation of the statement).

    My take on the Spacex is Mars habitation project is that Musk will put a bunch of edgelords on Mars, and then not really be able to follow up with adequate supply lines and the operation will be offline for a hundred years or so while the climate settles down. The people who live on Mars will then have been there alone for a century and in the 2100s we will send a follow up mission with hilarious consequences.

    • peepeepoopoo87 an hour ago

      Thunderf00t, is that you?

      • dools an hour ago

        Haha I had never heard of that dude, but I like the look of his content thanks!

        BTW you can tell I'm not Thunderf00t because he says that "the taxpayer" paid $3 billion. I would never use "taxpayer funding" language, I would only ever call it public money (because Treasury creates money when it spends).

  • resonious 17 minutes ago

    It's a step towards landing on Mars. They aren't even claiming to have landed.

mikewarot 2 hours ago

Long, long ago, Tunnel Diodes were going to usher in an era of ultra-fast computing because their negative resistance region allowed for current gain in the simple 2 pin device.

It didn't work out for most of it, but does show that you can do logic without transistors.

Think of these as incredibly slow negative resistance devices. Computing with them might be possible, barely. But sometimes that's all you need.

lmpdev 4 hours ago

I thought resettable fuses were already polymer based?

PPTCs are just plastic and metal with no semiconductors afaik

Is this actually an MIT article?

  • curtisf 3 hours ago

    From the paper,

    > This is, to the best of our knowledge, the first report of fully 3D-printed resettable fuses.

    I think unique the contribution is that the entire circuit -- active and passive -- can be made with this one single material. Normally, you need to use many different materials and chemical baths to make a circuit with active components, but using this metal-polymer mix, you can _just_ deposit the metal and you are finished.

torginus an hour ago

While mentally stimulating, this sounds practically not very useful. They're using a copper-doped polymer for printing, which probably has way worse properties anything we make PCB traces out of.

And the 3D part is gimmicky. We have built electronic systems of monstrous complexity just with planar printers.

Wake me up when someone build a system that can reliably make PCBs at home, with placing components, and doesn't cost an arm and a leg, and is cheap and easy to run.

peter_d_sherman 2 hours ago

>"They saw an interesting phenomenon in the material they were using, a polymer filament doped with copper nanoparticles.

If they passed a

large amount of electric current into the material, it would exhibit a huge spike in resistance

but would return to its original level shortly after the current flow stopped."

This is interesting -- large amounts of current being associated with increased resistance...

I have never seen or read about something like that with respect to other electronic components or systems.

It would be an interesting experiment to see if this effect could be simulated, and if so, under what conditions, in non-nanoparticle standard regular-sized electrical components...

I'm guessing (but not knowing!) that you'd you'd need a very high amount of current (like something from a car battery), but at a very low voltage, like maybe 0.1 or 0.01 volts (or less), and maybe like a very thin long wire made of some mostly-conducitive material, and then maybe something at some scale or low voltage if the experimenter was lucky...

Anyway, large current associated with increased resistance... I've never heard of that one before, except I suppose if the current heats the electrical path so much that it destroys it... which would be different for different materials, voltages, cross-section of conductors, temperatures, etc., etc.

I'd assume that wouldn't happen at the nanoscale and/or in a switching semiconductor... but perhaps I might be wrong on some level...

  • torginus an hour ago

    large amount of electric current into the material, it would exhibit a huge spike in resistance

    considering the low melting point of these 3d printing plastics, they probably melted the wire.

  • elictronic an hour ago

    Lightbulbs? High amount of current increases resistance.

graycat 5 hours ago

Deleted.

  • wrsh07 5 hours ago

    Did you comment on the wrong post? Or did the link get swapped out on you?

    • graycat 3 hours ago

      Thanks. Don't know what happened:

      Intended to comment on

      "Show HN: HN Update – Hourly News Broadcast of Top HN Stories (hnup.date)"

      at

      https://news.ycombinator.com/item?id=41893524

      but apparently somehow posted to

      "3D-Printed Active Electronics (news.mit.edu)"

      at

      https://news.ycombinator.com/item?id=41893524

      Just deleted the post at

      "3D-Printed Active Electronics (news.mit.edu)"

      and submitted the post to

      "Show HN: HN Update – Hourly News Broadcast of Top HN Stories (hnup.date)"

      Thanks.