How fast does your heart beat? It’s a tough question to answer, because our heart rate changes all the time depending on what we’re doing and how our body is behaving. However, [Ludwin] noted that resting heart rates often settle somewhere near 60 bpm on average. Thus, they entered a heart rate sensor to our 2025 One Hertz Challenge!

The build is based around a Wemos D1 mini, a ESP8266 development board. It’s hooked up to a MAX30102 heart beat sensor, which uses pulse oximetry to determine heart rate with a photosensor and LEDs. Basically, it’s possible to determine the oxygenation of blood by measuring its absorbance of red and infrared wavelengths, usually done by passing light through a finger. Meanwhile, by measuring the change in absorption of light in the finger as blood flows with the beat of the heat, it’s also possible to measure a person’s pulse rate.

The Wemos D1 takes the reading from the MAX30102, and displays it on a small OLED display. It reports heart rate in both beats per minute and in Hertz. if you can happen to get your heartrate to exactly 60 beats per minute, it will be beating at precisely 1 Hertz. Perhaps, then, it’s the person using Ludwin’s build that is actually eligible for the One Hertz Challenge, since they’re the one doing something once per second?

In any case, it shows just how easy it is to pick up biometric data these days. You only need a capable microcontroller and some off-the-shelf sensors, and you’re up and running.

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hackaday.com/2025/08/15/2025-o…

Rubber! It starts out as a goopy material harvested from special trees, and is then processed into a resilient, flexible material used for innumerable important purposes. In the vast majority of applications, rubber is prized for its elasticity, which eventually goes away with repeated stress cycles, exposure to heat, and time. When a rubber part starts to show cracks, it’s generally time to replace it.

Researchers at Harvard have now found a way to potentially increase rubber’s ability to withstand cracking. The paper, published in Nature Sustainability, outlines how the material can be treated to provide far greater durability and toughness.

Big Flex

Note the differences between a short-chain crosslinked structure, and the longer-chain tanglemer structure with far less crosslinks. The latter is far better at resisting crack formation, since the longer chain can deconcentrate stress over a longer distance, allowing far greater stretch before failure. Credit: research paper
The traditional method of producing rubber products starts with harvesting the natural rubber latex from various types of rubber tree. The trees are tapped to release their milky sap, which is then dried, processed with additives, and shaped into the desired form before heating with sulfur compounds to vulcanize the material. It’s this last step that is key to producing the finished product we know as rubber, as used in products like tires, erasers, and o-rings. The vulcanization process causes the creation of short crosslinked polymer chains in the rubber, which determine the final properties and behavior of the material.

Harvard researchers modified the traditional rubber production process to be gentler. Typical rubber production includes heavy-handed mixing and extruding steps which tend to “masticate” the polymers in the material, turning them into shorter chains. The new, gentler process better preserves the long polymer chains initially present in the raw rubber. When put through the final stages of processing, these longer chains form into a structure referred to as a “tanglemer”, where the tangles of long polymer chains actually outnumber the sparse number of crosslinks between the chains in the structure.
The gentler production method involves drying the latex and additive mixture at room temperature to form a film, before hot-pressing it to form the final tanglemer structure. This process isn’t practical for producing large, thick parts. Credit: research paper
This tanglemer structure is much better at resisting crack formation. “At a crack tip in the tanglemer, stress deconcentrates over a long polymer strand between neighbouring crosslinks,” notes the research paper. “The entanglements function as slip links and do not impede stress deconcentration, thus decoupling modulus and fatigue threshold.” Plus, these long, tangled polymer chains are just generally better at spreading out stress in the material than the shorter crosslinked chains found in traditional vulcanized rubber. With the stress more evenly distributed, the rubber is less likely to crack or fail in any given location. The material is thus far tougher, more durable, and more flexible. These properties hold up even over repeated loading cycles.

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Overall, the researchers found the material to be four times better at resisting crack growth during repeated stretch cycles. It also proved to be ten times tougher than traditional rubber. However, the new gentler processing method is fussy, and cannot outperform traditional rubber processing in all regards. After all, there’s a reason things are done the way they are in industry. Most notably, it relies on a lot of water evaporation, and it’s not currently viable for thick-wall parts like tires, for example. For thinner rubber parts, though, the mechanical advantages are all there—and this method could prove useful.

Ultimately, don’t expect to see new this ultra-rubber revolutionizing the tire market or glove manufacturing overnight. However, the research highlights an important fact—rubber can be made with significantly improved properties if the longer polymer chains can be preserved during processing, and tangled instead of excessively cross-linked. There may be more fruitful ground to explore to find other ways in which we can improve rubber by giving it a better, more resilient structure.

hackaday.com/2025/08/15/gentle…

Sembra che gli Stati Uniti abbiano già seriamente preso in considerazione il concetto di guerra autonoma. Il jet da combattimento autonomo della DARPA , risulta in grado di combattere senza pilota, non è più considerato una svolta: l’agenzia è passata alla fase successiva di sviluppo, con l’obiettivo di creare sistemi in grado di controllare un gruppo di jet da combattimento in missioni congiunte oltre il raggio visivo.

Il nuovo programma della DARPA, Artificial Intelligence Reinforcements (AIR), si basa sul progetto Air Combat Evolution (ACE) , che ha messo a confronto F-16 dotati di intelligenza artificiale con velivoli con equipaggio in un addestramento “dogfight”. L’obiettivo è aumentare l’autonomia fino al punto in cui tali velivoli possano operare in formazione, coordinandosi su lunghe distanze e in ambienti di combattimento complessi. Il programma fa parte di una più ampia militarizzazione dell’intelligenza artificiale che sta sollevando preoccupazioni sulla sua sicurezza.

Sebbene AIR sia stato avviato più tardi di ACE, il concetto in sé non è nuovo: la prima domanda per il programma è stata pubblicata nel 2022. Questa settimana, la DARPA ha assegnato silenziosamente a Systems & Technology Research (STR) un contratto da 11,3 milioni di dollari nell’ambito della cosiddetta “Opzione Uno“. Come ha spiegato l’agenzia, questa è già la seconda delle due fasi previste del programma, il che indica che il progetto sta procedendo.

All’inizio di AIR, il programma coinvolgeva sei appaltatori, ma nella seconda fase il numero è stato ridotto a quattro. STR è responsabile di una delle due aree tecniche chiave: lo sviluppo di algoritmi che consentiranno l’esecuzione distribuita e autonoma di missioni tattiche in tempo reale in ambienti incerti, in rapida evoluzione e complessi. La seconda area prevede la creazione di modelli rapidi e accurati in grado di tenere conto dell’incertezza e di migliorare automaticamente con l’accumulo di dati.

Secondo la documentazione iniziale, l’AIR dovrebbe utilizzare sistemi di sensori, sistemi di guerra elettronica e armi esistenti. Le fasi di test includeranno simulazioni, quindi test con un essere umano nel circuito di controllo e infine test su un vero velivolo da combattimento senza pilota. Sviluppi simili sono già stati dimostrati: l’esercito statunitense ha creato un sistema robotico in grado di abbattere autonomamente i droni.

Oltre a STR, al progetto hanno partecipato anche Lockheed Martin e BAE Systems , ma la DARPA non ha ancora reso noto chi sarà incluso esattamente nella seconda fase: la selezione dei partecipanti è ancora in corso. I dettagli del lavoro nella prima e nella seconda fase rimangono riservati, ma è noto che la prossima fase durerà circa 30 mesi e coprirà la parte restante del programma.

La questione di quando i piloti saranno effettivamente costretti a cedere il passo all’intelligenza artificiale rimane aperta. E mentre gli sviluppatori stanno testando l’autonomia tattica, i critici non escludono scenari più inaspettati, fino al punto che un giorno un jet da combattimento autonomo decida di abbandonare una missione di combattimento. Gli esperti avvertono che la diffusione dell’IA militare potrebbe rendere il mondo meno sicuro , poiché l’IA commette errori e le conseguenze possono essere fatali . La comunità internazionale sta cercando di sviluppare un patto globale contro l’IA militare .

L'articolo Droni in missione potranno decidere in modo autonomo quali uomini uccidere? proviene da il blog della sicurezza informatica.

This week, Hackaday’s Elliot Williams and Kristina Panos met up over the tubes to bring you the latest news, mystery sound, and of course, a big bunch of hacks from the previous week.

In Hackaday news, get your Supercon 2025 tickets while they’re hot! Also, the One Hertz Challenge ticks on, but time is running out. You have until Tuesday, August 19th to show us what you’ve got, so head over to Hackaday.IO and get started now. Finally, its the end of eternal September as AOL discontinues dial-up service after all these years.

On What’s That Sound, Kristina got sort of close, but this is neither horseshoes nor hand grenades. Can you get it? If so, you could win a limited edition Hackaday Podcast t-shirt!

After that, it’s on to the hacks and such, beginning with a talking robot that uses typewriter tech to move its mouth. We take a look at hacking printed circuit boards to create casing and instrument panels for a PDP-1 replica. Then we explore a fluid simulation business card, witness a caliper shootout, and marvel at one file in six formats. Finally, it’s a telephone twofer as we discuss the non-hack-ability of the average smart phone, and learn about what was arguably the first podcast.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

html5-player.libsyn.com/embed/…

Download in DRM-free MP3 and savor at your leisure.

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

• iTunes
• Spotify
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• Check out our Libsyn landing page

Episode 333 Show Notes:

News:

• Get Your Tickets For Supercon 2025 Now!
• Announcing The 2025 Hackaday One Hertz Challenge
• End Of The Eternal September, As AOL Discontinues Dial-Up

What’s that Sound?

• Think you know what the sound is? Fill out the form for your shot at a shirt.

Interesting Hacks of the Week:

• Josef Prusa Warns Open Hardware 3D Printing Is Dead
  
  • Continuous-Path 3D Printed Case Is Clearly Superior
  • FullControl – Unconstrained Design
  • The Trials Of Trying To Build An Automatic Filament Changer

  
  

• Talking Robot Uses Typewriter Tech For Mouth
• Hacking Printed Circuit Board To Create Casing And Instrument Panels
• That’s No Moon, Er, Selectric
• The WHY 2025 Badge And Its 18650s
• LEDs That Flow: A Fluid Simulation Business Card

Quick Hacks:

• Elliot’s Picks:
  
  • Calipers: Do You Get What You Pay For?
  • Building A Trash Can Reverb
  • Coping With Disappearing Capacitance In A Buck Converter
  • One File, Six Formats: Just Change The Extension

  
  

• Kristina’s Picks:
  
  • 2025 One Hertz Challenge: Abstract Aircraft Sculpture Based On Lighting Regulations
  • Don’t Say This DIY Diskette Was A Flop
  • Digital Etch-A-Sketch Also Plays Snake

  
  

Can’t-Miss Articles:

• Smartphone Hackability, Or, A Pocket Computer That Isn’t
  
  • Ask Hackaday: Why Aren’t We Hacking Cellphones?

  
  

• The World’s First Podcaster?

hackaday.com/2025/08/15/hackad…

Despite the regularly proclaimed death of physical media, new audio albums are still being published on CD and vinyl. There’s something particularly interesting about Lorde’s new album Virgin however — the CD is a completely clear disc. Unfortunately there have been many reports of folks struggling to get the unique disc to actually play, and some sharp-eyed commentators have noted that the CD doesn’t claim to be Red Book compliant by the absence of the Compact CD logo.
The clear Lorde audio CD in all its clear glory. (Credit: Adrian’s Digital Basement, YouTube)
To see what CD players see, [Adrian] of Adrian’s Digital Basement got out some tools and multiple CD players to dig into the issue. These players range from a 2003 Samsung, a 1987 NEC, and a cheap portable Coby player. But as all audio CDs are supposed to adhere to the Red Book standard, a 2025 CD should play just as happily on a 1980s CD player as vice versa.

The first step in testing was to identify the laser pickup (RF) signal test point on the PCB of each respective player. With this hooked up to a capable oscilloscope, you can begin to see the eye pattern forming. In addition to being useful with tuning the CD player, it’s also an indication of the signal quality that the rest of the CD player has to work with. Incidentally, this is also a factor when it comes to CD-R compatibility.

While the NEC player was happy with regular and CD-R discs, its laser pickup failed to get any solid signal off the clear Lorde disc. With the much newer Samsung player (see top image), the clear CD does play, but as the oscilloscope shot shows, it only barely gets a usable signal from the pickup. Likewise, the very generic Coby player also plays the audio CD, which indicates that any somewhat modern CD player with its generally much stronger laser and automatic gain control ought to be able to play it.

That said, it seems that very little of the laser’s light actually makes it back to the pickup’s sensor, which means that the gain gets probably cranked up to 11, and with that its remaining lifespan will be significantly shortened. Ergo it’s probably best to just burn that CD-R copy of the album and listen to that instead.

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hackaday.com/2025/08/15/why-lo…

[post aggiornato dopo aver spostato i contenuti qui su Friendica]

Ecco i link diretti ai post con le tappe del mio viaggio di quest'estate in Mecklenburg-Vorpommern e Schleswig-Holstein (aprire sempre le didascalie/testi alternativi delle immagini per qualche particolare in più)

Ulm

Schloss Ulrichshusen (concerto)

Ankershagen (museo Schliemann)

Greifswald, Boddenlandschaft (museo Caspar David Friedrich)

Stralsund (fabbrica di carte da gioco)

Wismar, Schwerin

Lubecca

Marne (concerto)

Amburgo (Kunsthalle) - somiglianze?

Stade (Kunstautomat)

Celle

Bergen-Belsen

Hildesheim

Lipsia (itinerario musicale, San Nicola)

Norimberga

Ritratto di gatta viaggiatrice

Il concerto di Gastone Pietrucci e La Macina insieme a Elisa Ridolfi, vincitrice del Premio Tenco 2024 per la migliore opera prima, si è rivelato un'esperienza suggestiva e toccante. Il luogo prescelto, una radura a pochi metri dal borgo medievale di Cerreto di Montegiorgio, ha donato all'evento un'atmosfera intima e quasi magica. Seduti su semplici assi di legno grezzo, ci siamo ritrovati a stretto contatto con i musicisti, annullando ogni barriera e favorendo una vera e propria comunione tra artisti e ascoltatori.
Nonostante la qualità del suono non fosse sempre eccelsa, quasi a voler dimostrare che quello che conta è la sincerità e non la perfezione artificiale, l'espressività dei musicisti ha superato ogni limite tecnico. Le emozioni scaturite da ogni nota e da ogni parola sono state così coinvolgenti da rendere l'esperienza unica e indimenticabile.
L'esibizione ha offerto un viaggio musicale che ha saputo unire brani originali ad omaggi ad alcuni dei più grandi cantautori italiani: le canzoni di De André, Ciampi, Tenco e Piero Cesanelli (padre della rassegna musicale Musicultura) sono state reinterpretate con passione e rispetto. Momenti di rara intensità si sono raggiunti con le esecuzioni appassionate di "Vedrai, vedrai" di Luigi Tenco e del canto popolare "Sotto la croce Maria", così come con la sorprendente interpretazione della “Ballata degli impiccati” di De André, che è stata introdotta dalla voce nuda e dirompente di Elisa Ridolfi.
Questi passaggi hanno trasformato la serata da un semplice concerto in un'esperienza quasi spirituale di condivisione di sentimenti e storie, confermando ancora una volta il valore di una musica che affonda le radici nella tradizione, ma che sa parlare con forza e attualità al cuore di chi ascolta.
(13agosto2025 - #worldland festival)