Squeezing Fluids With The Right Peristaltic Pump For The Task

May 3, 2026 by Maya Posch 2 Comments

Peristaltic pumps are a very simple and effect device for transferring fluids without said fluid ever coming into contact with any part of the pump mechanism. At their core they involve a mechanism squeezing fluids through compressible tubing, but there are various implementations of such a mechanism that all have their pros and cons. In a recent article by [T. K. Hareendran] over at EDN these types are discussed and when you’d want to pick one over the other.

Also known as a roller pump, these positive displacement pumps have been known since the 19th century, finding uses in industrial, medical, research, agriculture and many other fields. Each of these fields have different requirements with the use of a peristaltic pump as a dosing pump being a specific application whereby e.g. a stepper motor can be used to provide exact dosing.

For industrial settings the typical rollers that compress the tube are replaced with shoes that provide higher pressures and endurance, with overall a bewildering number of motor types and tubing materials available. Depending on what your project needs, you may opt for continuous flow, fine control over dosing, the ability to reverse the flow, etc.

Unless your project is particularly rugged, a roller-based mechanism should be fine, while silicone tubing is great for biocompatibility and PVC is a cheaper tube material option. If you intend to transfer certain kinds of chemicals that will react with each of these there are some more exotic tubing options available as well.

We have previously covered projects that use a peristaltic pump for rather interesting things, such as DIY pharmaceutics, in a home-grown flow battery, not to mention creating DIY peristaltic pumps from first principles.

Debugging A Stopped Foucault Pendulum’s Electronics

May 2, 2026 by Maya Posch 14 Comments

After the Foucault pendulum at the Houston Museum of Natural Science stopped working a while back after maintenance on the building, workers set out to determine what was wrong with the mechanism that normally keeps it in motion. Fortunately, it turned out that all they had to do was fiddle with some knobs to get everything dialed back in proper-like.

When we previously covered this dire event, it was claimed that this was a one-off system, hacked together by some random bloke. But as can be seen in the video and further detailed in the comments to the video the reality is far more interesting.

This particular Foucault pendulum is one of many that were created by the California Academy of Sciences, with hundreds of them installed throughout the US and possibly elsewhere. That said, since a pendulum of any description will never be a perpetual motion device, the electromagnet installed near the top of the installation has to carefully add some kinetic energy back that was lost due to friction as the pendulum moves around.

Sadly the video doesn’t go into much detail on what exactly was wrongly configured with this particular pendulum. Keeping a weight at the end of a long cable moving around at a set velocity is a tricky business, so it’s little wonder that getting some parameters wrong would engage and disengage the electromagnets at the wrong times and making the pendulum stop swinging.

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Running DOOM On A Travel Router With Touch Screen

May 1, 2026 by Maya Posch 10 Comments

Continuing his quest to put DOOM on literally everything that has a capable enough processor and a screen, [Aaron Christophel]’s most recent target is a Slate 7 Pro travel router. With a generous 2.8″ touch screen and a lot of onboard processing power to handle all the advertised networking and routing features via its WAN and (W)LAN interfaces, it should be able to run the game really quite well. As usual the main question is how to get the game to run on it first.

The port of choice is fbdoom, with instructions on how to run it on this router provided on the GitHub project page. The reason for the touch screen is so that you can see the status of interfaces and interact with it without having to open the web interface. Boringly, this router has an SSH daemon ready to connect to, giving you full root access to the Linux-based firmware.

It’s just your typical AArch64 ARM-based system, with the gl_screen process running for the touch screen display. From there it was easy enough to deduce the settings to jot into fbdoom so that it too could use the same screen and touch inputs. After copying the compiled binary with SCP over to the router, it can then be started like any application. With touch inputs somewhat awkwardly mapped to certain areas of the touch screen, it’d be nice to see the USB 2.0 port used for USB HID inputs, but it does show how easy things can be when it runs something like Linux and you got full root access.

Incidentally this also heavily blurs the lines between something like a Valve Steamdeck and a router, with the latter just missing some gamepad controls on the side to do some on-the-go gaming when you’re not using it for routing network traffic.

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Running Linux On The PS5 With A Hypervisor Exploit

May 1, 2026 by Maya Posch 7 Comments

Since Sony’s PlayStation 5 console is quite literally an AMD-based gaming PC with a custom mainboard, the only thing that really keeps anyone from just installing another operating system on it is the hypervisor-based firmware. Since in older firmware for the original ‘phat’ PlayStation 5 there exists a hypervisor exploit, this logically means that you can totally run Linux on them, as demonstrated by [Andy Nguyen] with the PS5-linux project on GitHub.

PS5 firmware version 5.x from 2022 seems to have at least partially addressed this particular vulnerability, so this leaves firmware versions 3.x and 4.x supported by PS5-linux for now. Firmware versions 1.x and 2.x also have this vulnerability, but [Andy] hasn’t added support for these yet. As for the prospect of running PS5-linux on 5.x firmware the prospect is less certain, but it’s reckoned that since the OS would then run inside the hypervisor it’d be quite limited in its functionality. Firmware versions 6+ are currently still firmly locked-down.

If you have an original PS5 kicking around with the right firmware version, to use the project you need a 64+ GB USB drive to run from and USB dongles for Wi-Fi/Ethernet. For Bluetooth support you also need a dongle. With the USB drive inserted into the console, on boot it runs the jailbreak exploit and sends the bootloader as payload. If all goes well you should then see the desktop of Ubuntu 26.04 Resolute Raccoon pop up.

It’s arguable how practical this currently is, but since it doesn’t modify the PS5 firmware it’s not permanent at least. Unfortunately Linux doesn’t have drivers for much of the PS5’s hardware, so the available video resolutions are limited, power management features such as standby are not working, and there are currently bugs related to HDMI audio and video output on some monitors.

It’s unfortunate that features like OtherOS (before it got pulled) on the PlayStation 3 or the official Linux for the PlayStation 2 aren’t a thing any more, but this hack offers at least some glimpse of what that could have been like for a modern Sony console.

Five Different Styles Of Cardboard Hinges

April 30, 2026 by Maya Posch 4 Comments

Simple paper hinge. (Credit: Itoshige Studio, YouTube)

One doesn’t generally associate cardboard with structural components like hinges, but [Itoshige Studio] assures us that you can absolutely create hinges out of this ubiquitous material. In total the video covers five different designs, ranging from the simple and straightforward to an interlocking tab design that approximates a typical steel hinge with paper rod to keep both sides of the hinge together.

The most simple hinge is unsurprisingly just a strip of craft paper, which is also demonstrated as the hinge for a wooden box in lieu of the typical metal hinge. This same principle is then demonstrated for a fancy cardboard box.

From here the hinge designs increasingly get more involved, with first a seamless hinge variation, and then a kamichoban hinge design that’s inspired by traditional Japanese room dividers and furniture, using panels that are interconnected with overlapping sections to create a fascinatingly flexible hinge that can fully fold either way.

The flush hinge design is somewhat like the craft paper hinge, but significantly fancier and probably sturdier, while also looking pretty good on something like a cabinet. Finally the interlocking tab hinge is effectively a cardboard version of the hinge design that’s found on every room’s door, with a similar level of flexibility. This is obviously the trickiest one to assemble and get right, but it has its own charm.

Considering that all of these examples use regular corrugated cardboard that we get shipped to our homes by the truckload, the cost to try these examples is your time plus some basic tools and glue. The author also sells a book that contains templates – in addition to digital versions – for these hinges and other designs, if you’d like to enjoy the 100% paper experience.

Thanks to [greg_bear] for the tip.

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Transcribing The Source Of The First DOS For The IBM PC

April 30, 2026 by Maya Posch 8 Comments

Doing software archaeology can be a harrowing task, as rarely do you find complete snapshots of particular versions of software. Case in point the development of MS-DOS – also known as IBM PC DOS – from 86-DOS, which recently got a lucky break in the form of printed source listings. These printouts come courtesy of [Tim Paterson], the creator of 86-DOS and of MS-DOS during his time working for Microsoft.

These code listings contain the sources of the 86-DOS 1.00 kernel, multiple development snapshots, and also listings for utilities like CHKDSK. These printed listings additionally contain many handwritten notes, making transcribing it into working source code somewhat of a chore. The results can be found on the GitHub project page, with the original scans available on Archive.org.

Of the ten bundles of continuous feed paper prints all but two have been transcribed so far, though with the various DOS kernels and the Seattle Computer Products (SCP) assembler source already ready for compilation. This includes 86-DOS 1.00, MS-DOS 1.25 and PC-DOS 1.00-dev, requiring the same SCP assembler to create a binary.

In the project page README a number of blog posts are also linked that add even more technical detail. Anyone who wants to pitch in with transcribing and/or testing recovered source code is welcome to do so.

Why Model Collapse In LLMs Is Inevitable With Self-Learning

April 29, 2026 by Maya Posch 72 Comments

There is a persistent belief in the ‘AI’ community that large language models (LLMs) have the ability to learn and self-improve by tweaking the weights in their vector space. Although there’s scant evidence that tweaking a probability vector space is anything like the learning process in biological brains, we nevertheless get sold the idea that artificial general intelligence (AGI) is just around the corner if we do just enough tweaking.

Instead of emerging super intelligence, the most likely outcome is what is called model collapse, with a recent paper by [Hector Zenil] going over the details on why self-training/learning in LLMs and similar systems is a fool’s errand. For those who just want the brief summary with all the memes, [Metin] wrote a blog post covering the basics.

In the end an LLM as well as a diffusion model (DM) is a statistical model of input data using which a statistically likely output can be generated (inferred) based on an input query. It follows intuitively that by using said output to adjust the model with, the model will over time converge on a kind of statistical singularity rather than some ‘AI singularity’ event. This is also why these models need to be constantly trained with external, human-generated data in order to prevent such a collapse.

In the paper by [Hector] a mathematical model is created to demonstrate that an LLM, DM or similar statistical model undergoes degenerative dynamics whenever said external input is reduced. Although in the paper a mechanism is suggested to counter the entropy decay within the model, the ultimate point is that a statistical model cannot improve itself without continuous external anchoring.

The idea of LLMs being at all intelligent in any sense has been a contentious one, with the concept of language models being equated with ‘AI’ dating back to the 20th century, including as fun home computer projects. Much of the problem probably lies in humans projecting intelligent behavior onto these statistical models, turning LLMs into ‘counterfeit humans’, not helped by how closely generated text can resemble something written by a human, even if completely confabulated.

Thanks to [deshipu] for the tip.