Building a Xenon Lamp for Spectroscopy

Before a spectrometer can do any useful work, it needs to be calibrated to identify wavelengths correctly. This is usually done by detecting several characteristic peaks or dips in a well-known light source and using these as a reference to identify other wavelengths. The most common reference for hobbyists is the pair of peaks produced by a mercury-vapor fluorescent light, but a more versatile option is a xenon-bulb light source, such as [Markus Bindhammer] made in his latest video.

A xenon gas discharge produces a wide band of wavelengths, which makes it a useful illumination source for absorbance spectroscopy. Even better, Xenon also has several characteristic spikes in the infrared region. For his light source, [Markus] used an H7 xenon bulb meant for a vehicle headlight. The bulb sits in the center of the source, with a concave mirror behind it and a pair of converging lenses in front of it. The converging lenses focus the light onto the end of an optical cable made of PMMA to better transmit UV. A few aluminum brackets hold all the parts in place. The concave mirror is made out of a cut-open section of aluminum pipe. The entire setup is mounted inside an aluminum case, with a fan on one end for cooling. To keep stray light out of the case, a light trap covers the fan’s outlet.

[Markus] hadn’t yet tested the light source with his unique spectrometer, but it looks as though it should work nicely. We’ve seen a wide variety of amateur spectrometers here, but it’s also illuminating to take a look at commercial scientific light sources.

youtube.com/embed/eoKuQDhld10?…

hackaday.com/2025/11/02/buildi…

I robot iniziano a prendere posto nella società grazie a nuovi algoritmi AI

Il 25 settembre, Google DeepMind ha pubblicato un video che mostra come le sue piattaforme umanoidi gestiscono attività quotidiane articolate in più fasi utilizzando il ragionamento multimodale.

In una serie di dimostrazioni, le macchine hanno eseguito con sicurezza sequenze di azioni, tra cui l’ordinamento di oggetti secondo regole predeterminate.

L’intelligenza di questi sistemi si basa sulla famiglia Gemini Robotics 1.5. Due componenti lavorano insieme: il modello base traduce segnali visivi e messaggi testuali in movimenti specifici, mentre la versione modificata di Gemini Robotics-ER 1.5 crea piani e ragionamenti passo dopo passo sulla situazione attuale, scegliendo la giusta sequenza di passaggi.

Il cosiddetto test della banana dimostra bene i progressi. In precedenza, al robot era richiesto solo di raccogliere una banana e metterla in una ciotola: un comando, un risultato.

Ora, il sistema ordinava tre frutti diversi per colore e li posizionava su piatti. Jie Tang, ricercatore senior di Google DeepMind, ha dimostrato l’esperimento; il sistema a due bracci, basato sui manipolatori Franka, ha completato l’intera sequenza senza intoppi.

La piattaforma umanoide Apollo di Apptronik è stata testata anche in un’attività di lavanderia. La macchina suddivideva i capi in base alla tonalità in due contenitori: uno per i bianchi e uno per i neri. Dopo il primo tentativo riuscito, gli ingegneri hanno scambiato i contenitori per vedere se il sistema avrebbe rilevato lo scambio e modificato le sue azioni. Apollo ha riconosciuto la nuova disposizione e ha completato correttamente la selezione.

Gemini Robotics 1.5 supporta l’apprendimento incarnato: il robot esplora l’ambiente circostante con il corpo, i sensori e le telecamere, e poi agisce in base alle proprie osservazioni. ALOHA 2 è stato utilizzato nella maggior parte delle scene, ma gli stessi scenari possono essere gestiti anche da Apollo e dal sistema Franka a due bracci.

Sono state aggiunte anche funzioni basate su agenti. Ad esempio, il sistema può essere incaricato della raccolta differenziata: cercherà su Internet le normative locali, valuterà visivamente ogni oggetto, lo assegnerà al compost, al riciclaggio o ai rifiuti ed eseguirà l’intero processo, dalla decisione allo smaltimento nel contenitore appropriato.

Questo livello di coerenza è raggiunto attraverso la collaborazione di due componenti: una responsabile del percorso dalla percezione al movimento, l’altra della pianificazione e della logica. Questa architettura rende l’esecuzione di attività nel mondo reale più intuitiva e affidabile.

La sicurezza ha ricevuto particolare attenzione. I robot sono addestrati a valutare i rischi in modo proattivo, rispettare i limiti umani ed evitare situazioni pericolose. Con il supporto di team specializzati e il test ASIMOV aggiornato, Gemini Robotics-ER 1.5 ha raggiunto una posizione di leadership nei test, il che dovrebbe facilitare l’implementazione accurata di sistemi simili al di fuori del laboratorio.

L'articolo I robot iniziano a prendere posto nella società grazie a nuovi algoritmi AI proviene da Red Hot Cyber.

Multitasking On The Humble Z80 CPU

Multitasking is something we take for granted these days. Just about every computer we use, from our desktops to our phones, is capable of multitasking. It might sound silly to implement multitasking on lower-spec machines from many decades ago, given their limited resources, but it can be done, as [bchiha] demonstrates on a Z80-based machine.

[bchiha] has achieved pre-emptive multitasking on the TEC-1G Z80 computer, a modern reimagining of the classic Talking Electronics TEC-1 from the 1980s. The proof of concept code allows running up to eight separate tasks at once. Task switching runs on interrupts, triggered at approximately 50 Hz. When an interrupt fires, the CPU registers are transferred onto that task’s stack, and the next task’s stack is swapped to the stack pointer to allow execution of the new task to proceed. There is an overhead, of course, with [bchiha] noting that the task swapping routine itself takes about 430 clock cycles to run in between tasks.

Multitasking took some time to appear on home computers for good reason—it’s not very useful unless you have a machine with enough power to practically run multiple tasks at once. While a Z80 machine like this can do multitasking, you’d better hope each task is pretty tiny to avoid each individual task taking forever to run.

[bchiha] has made the simple multitasking code available on Github for the curious. We’ve featured multitasking work on other unconventional platforms before, too, like the Arduino Uno. Video after the break.

youtube.com/embed/tMYGlYO3v9U?…

[Thanks to Stephen Walters for the tip!]

hackaday.com/2025/11/01/multit…

An Audio Brick For Your Smart Home

If you’ve ever wanted to pump sound to all the rooms of your house, you might use any one of a number of commercial solutions. Or, you could go the more DIY route and whip up something like the Esparagus Audio Brick built by [Andriy].

The concept is simple—it’s a small unit, roughly the size of a brick, which streams high-quality audio. It’s based around an ESP32, which pulls in digital audio over Wi-Fi or Ethernet. The microcontroller is hooked up to a TAS5825M DAC, which comes with a built-in amplifier for convenience. The Esparagus is designed for integration with Home Assistant, allowing for easy control as part of a smart home setup. It’s also compatible with Spotify Connect, AirPlay, and Snapcast—the latter of which provides excellent sync when using multiple units across several rooms.

Design files are available on Github for the curious. We’ve seen other neat projects in this space, before, too—like the charmingly-named OtterCast. Video after the break.

youtube.com/embed/Ft5_anhSEE8?…

hackaday.com/2025/11/01/an-aud…

Building a PV Solar-Powered Quadcopter

The solar-powered quadcopter from below. (Credit: Luke Maximo Bell)
One of the most frustrating parts about flying a quadcopter is having to regularly swap battery packs, as this massively limits what you can do with said quadcopter, never mind its effective range. Obviously, having the sun power said quadcopter during a nice sunny day would be a much better experience, but how workable is this really? While airplanes have used solar power to stay aloft practically indefinitely, a quadcopter needs significantly more power, so is it even possible? Recently, [Luke Maximo Bell] set out to give it a whirl.

His quadcopter build uses a large but very lightweight carbon fiber frame, with large 18″ propellers. This provides the required space and lift for the solar panel array, which uses 27 razor-thin panels in a 9×3 grid configuration supported by a lightweight support frame.

Due to the lightweight construction, the resulting quadcopter actually managed to fly using just the direct power from the panels. It should be noted however that it is an exceedingly fragile design, to the point that [Luke]’s cat broke a panel in the array when walking over it while it was lying upside-down on a table.

After this proof of concept, [Luke] intends to add more panels, as well as a battery to provide some buffer and autonomous flying hardware, with the goal of challenging the world record for the longest flying drone. For the rest of us, this might make for a pretty cool idea for a LoRaWAN mesh node or similar, where altitude and endurance would make for a great combo.

youtube.com/embed/isAQEU0mZBo?…

hackaday.com/2025/11/01/buildi…

Vogtsbauernhof

Visited the Black Forest open air museum Vogtsbauernhof in 77793 Gutach / Germany. This is a huge areal that has several very old farm buildings, that have been carefully de- and reconstructed on this site. There are often also tours, demonstrations or hands-on activities how people used to live in the Black Forest area but as a half-timber nutter I’m mostly interested in the buildings. These are from various periods starting as early as 1407 (though that’s an often refurbished exception).

Shooting any sort of pictures with my smartphone camera was very hard because the insides of the buildings are unbelievable dark and hardly lit. I guess this is driving home a point in itself. Anyway I did my best to improve the photos somewhat with Darktable (not that I have any idea what I’m doing there). Also the galleries won’t syndicate so you’ll have to check the source for the pictures.

Here are some of the pictures that are very dark in reality.

We also looked at plenty of farm equipment, of course. In fact one of the farms is still operated and has livestock around.

One of the most interesting things I found was a “mini house” that is basically of fridge for milk. It utilizes a water stream to keep milk on the inside cold.

Some of these buildings simply look gorgeous on the outside but my kids were pretty certain that they’d not actually want to life in such a building. Beside the darkness on the inside one could also always feel how air makes it inside. There’s always a slight breeze, which is probably nice in the summertime but not so much in the wintertime. Especially with only a few places around to heat the buildings.

One of their major show pieces is probably the Schlössle von Effringen, which is basically a mini castle that has been remade again and again dating back to ~11C.

This is also where I shot most of my pictures. Sadly we were running out of time and I have to revisit this again so look at some things a little closer. And maybe leave the kids at home too. They don’t really have the required patience.

I also rather enjoyed the various kitchens, that were almost all “smoke kitchens” – means the smoke from the kitchen fire was used to conserve food. This is a very medieval thing to do. Sadly the pictures I made don’t do them justice since they are basically black holes, that cameras struggle hard with.

One of the things I enjoyed most are models of various buildings. I made many photos of these for inspiration. Maybe I’ll come back to recreating such buildings in the Rising World game one day.

And last some unsorted photos in portrait mode (ugh, it happens, mkay?)

Website of the museum is: vogtsbauernhof.de/en with plenty of more pictures and a 360deg tour. Can recommend. Alas bring food along – the restaurants next to the site are rather expensive. Museum is worth every cent though IMHO.

This content is licensed under a Creative Commons Attribution 4.0 International license.

beko.famkos.net/2025/11/01/vog…

#Halftimber #timberframed