Using light to 3D print liquid resins is hardly a new idea. But researchers at the University of Texas at Austin want to double down on the idea. Specifically, they use a resin with different physical properties when cured using different wavelengths of light.

Natural constructions like bone and cartilage inspired the researchers. With violet light, the resin cures into a rubbery material. However, ultraviolet light produces a rigid cured material. Many of their test prints are bio-analogs, unsurprisingly.

Even more importantly, the resin materials connect naturally, so you don’t have as much worry about a piece made with two materials delaminating at the interface. You can control the exact properties by shifting the light frequency one way or another. We read the actual paper, but it wasn’t clear to us if, after curing in a rubbery state, the part could still cure hard in, for example, sunlight. The paper is available in Nature Materials, but if you don’t have a subscription, try your local library or University.

Maybe just the thing for that tunable laser project. Of course, you can use multicolor FDM printers with two types of filaments. You only need to convert the model over.

hackaday.com/2025/07/10/double…

If you’re looking for a long journey into the wonderful world of instrument hacking, [Arty Farty Guitars] is six parts into a seven part series onhacking an existing guitar into a guitar-hurdy-gurdy-hybrid, and it is “a trip” as the youths once said. The first video is embedded below.

The Hurdy-Gurdy is a wheeled instrument from medieval europe, which you may have heard of, given the existence of the laser-cut nerdy-gurdy, the electronicmidi-gurdy we covered here, and the digi-gurdy whichseems to be a hybrid of the two. In case you haven’t seen one before, the general format is for a hurdy-gurdy is this : a wheel rubs against the strings, causing them to vibrate via sliding friction, providing a sound not entirely unlike an upset violin. A keyboard on the neck of the instrument provides both fretting and press the strings onto the wheel to create sound.

[Arty Farty Guitars] is a guitar guy, so he didn’t like the part with about the keyboard. He wanted to have a Hurdy Gurdy with a guitar fretboard. It turns out that that is a lot easier said than done, even when starting with an existing guitar instead of from scratch, and [Arty Farty Guitar] takes us through all of the challenges, failures and injuries incurred along the way.

Probably the most interesting piece of the puzzle is the the cranking/keying assembly that allows one hand to control cranking the wheel AND act as keyboard for pressing strings into the wheel. It’s key to the whole build, as combining those functions on the lower hand leaves the other hand free to use the guitar fretboard half of the instrument. That controller gets its day invideo five of the series. It might inspire some to start thinking about chorded computer inputs– scrolling and typing?

If you watch up to the sixth video, you learn that that the guitar’s fretting action is ultimately incompatible with pressing strings against the wheel at the precise, constant tension needed for good sound. To salvage the project he had to switch from a bowing action with a TPU-surfaced wheel to a sort of plectrum wheel, creating an instrument similar to thethousand-pick guitar we saw last year.

Even though [Arty Farty Guitars] isn’t sure this hybrid instrument can really be called a Hurdy Gurdy anymore, now that it isn’t using a bowing action, we can’t help but admire the hacking spirit that set him on this journey. We look forward to the promised concert in the upcoming 7th video, once he figures out how to play this thing nicely.

Know of any other hacked-together instruments that possibly should not exist? We’re always listening for tips.

youtube.com/embed/tqtJN4Xitqo?…

hackaday.com/2025/07/10/hackin…

è difficile restare fedele ai miei valori e convinzioni.
Non so.. Fare la spesa boicottando prodotti di aziende che traggono profitto dal genocidio palestinese (ad esempio, non mi ero mai resa conto che la mia mayo preferita fosse di Nestlé 🙁

Pause caffè piene di discorsi superficiali e di disinformazione, gossip sui colleghi a cui non voglio partecipare - ma non voglio nemmeno restare sempre isolata.

Essere onesta, in un ambiente di lavoro tossico.

-

*l'articolo non le rende giustizia: la cesta solidale, l'ho -orgogliosamente- creata (e ripristinata diverse volte) io, durante la pandemia, e da allora resiste 😀

#boicottare #cestasolidale #lavoro #valori #mayonnaise #thomy #nestle

According to [Casey Connolly], Qualcomm’s release of how to interact with their embedded USB debugging (EUD) is a big deal. If you haven’t heard of it, nearly all Qualcomm SoCs made since 2018 have a built-in debugger that connects to the onboard USB port. The details vary by chip, but you write to some registers and start up the USB phy. This gives you an oddball USB interface that looks like a seven-port hub with a single device “EUD control interface.”

So what do you do with that? You send a few USB commands, and you’ll get a second device. This one connects to an SWD interface. Of course, we have plenty of tools to debug using SWD.

In particular, there’s a fork of OpenOCD that knows how to use EUD, although it required a library that wasn’t available to us mere mortals. But now it is, so smooth sailing, right?

Um, no. Unless you have a very specific build configuration, the code won’t compile. Luckily, the fixes are not that hard and are available. The OpenOCD fork is a bit out of date, too. But with perseverance, it all worked.

In addition to the SWD device, there appears to be a COM and trace peripheral available, although those may need more work to be usable. If you make progress on those, let us know.

SWD debugging can be very handy. While not everyone likes debuggers, we’ve been a fan of hardware-based debugging for a long time.

hackaday.com/2025/07/10/embedd…

When we do textbook analysis, we tend to ignore the real-world concerns for the sake of learning. So, a typical theoretical voltage divider is simply two resistors. But if you examine a low-pass RC filter, you’ll see a single resistor and a capacitor. What if you combine them? That’s what [Old Hack EE] did in a recent video, and you can check it out below.

It helps if you are familiar with Thevenin equivalents and, of course, Ohm’s Law. There’s also a bit of algebra, but nothing too complicated. The example design has a lossy filter at 100 Hz.

Of course, RC filters are easy to understand if you think of them as voltage dividers with a frequency-variable resistance, which is what the math is basically saying. The load impedance, in this case, is R2 in parallel with Xc at a given frequency.

He mentions that you might find a circuit like this in a power supply. However, it is also common to see this circuit wherever a divider drives a load with capacitance or even parasitic capacitance in cables or circuit boards.

We’ve discussed Thevenin equivalence modeling before. If you want really good filters, you are probably going to need op-amps.

youtube.com/embed/7h5irBPDMrk?…

hackaday.com/2025/07/10/voltag…

Consiglio la lettura di questo libro.

Leggete l'estratto di questo libro, e poi pensate a Travaglio, a Orsini, al Fatto Quotidiano.

Poi chiedetevi perché siamo molto in basso nelle classifiche sull'informazione libera a livello mondiale.

"Secondo il sociologo della Chapman University della California, Andrea Molle, intervistato dalla RAI[76], “l’ideologia del Gruppo Wagner, che si associa alla sua dimensione per così dire aziendale, associa il neonazismo con il neopaganesimo slavo molto diffuso in Russia a partire dagli anni ‘70 del secolo scorso. Io parlerei di una forma esoterica di nazismo”. Il professore fa esplicito riferimento ad una particolare “declinazione dell’ideologia nazionalsocialista” con la quale venivano fusi gli elementi classici del nazismo con altri tipici del misticismo, occultismo ed esoterismo in voga in Germania a cavallo tra il 1800 ed il 1900. “Il Gruppo Wagner - afferma - riprende alcuni di questi contenuti nella propria estetica, come l’uso di rune sui propri mezzi, e nelle ritualità che sembrano caratterizzarlo”. Il sociologo parla anche di contatti tra Wagner e gli ambienti legati all’ultra destra e nazionalisti russi, i cui militanti sarebbero in larga parte impiegati anche nelle operazioni militari in Ucraina, ma non solo russi. Spiega anche che “abbiamo notizie di rapporti tra il gruppo Wagner e altri gruppi di estrema destra in Europa, ma anche negli Stati Uniti e in altri paesi del mondo. Alcuni ricercatori sostengono che negli ultimi anni, membri di gruppi estremisti (ad esempio tedeschi) e dei paesi dell’est Europa abbiano partecipato a sessioni di addestramento organizzate dalle PMC (private military company) russe tra le quali è ragionevole pensare anche il Gruppo Wagner”. Un ruolo determinante nella formazione e nell’addestramento delle milizie non ufficiali delle quali si avvale il Cremlino spetta, come si è visto, al Movimento Imperiale Russo, al quale ha dedicato attenzione anche il Centro per la Sicurezza e la Cooperazione Internazionale (CISAC)[77] centro di ricerca della prestigiosa Università di Stanford in California. Secondo il CISAC, il MIR “è un'organizzazione militante della supremazia bianca di estrema destra con sede a San Pietroburgo, in Russia. Fondato nel 2002, il gruppo promuove il nazionalismo etnico russo, sostiene la restaurazione del regime zarista russo e cerca di alimentare l'estremismo della supremazia bianca in Occidente. MIR (o RIM) mantiene contatti con gruppi neonazisti e suprematisti bianchi in Europa e negli Stati Uniti."

Setaccioli, Marco. Scemi di pace: Come i "pacifinti" ingannano l'Italia, diffondendo e mascherando le menzogne del Cremlino (pp.177-178). Edizione del Kindle.

#ucraina
#guerra
#mosca
#russia
#nazismo
#neonazismo
#wagner
#distopia
#disinformazione
#ilfattoquotidiano
#Orsini