The Zen Must Flow From Arrakis Sand Table

In Dune, the Fremen people of Arrakis practice an odd future hybrid religion called “zensunni.” This adds an extra layer of meaning to the title of [Mark Rehorst]’s Arrakis 3.0 sand table, given that the inspiration for the robotic sand table seems to be Zen gardens from Japan.

The dunes on the tabletop version of Arrakis owe nothing to sand worms, but are instead created a rolling metal ball. With all workings happening below, it looks quite magical to the uninitiated, but of course it’s not magic: it’s magnets. Just beneath the tabletop and its sands, the steel ball is being dragged along by the magnetic field of a powerful neodynium magnet.

That magnet is mounted in a CoreXY motion system that owes more than a little bit to modern 3D printers. Aside from the geometry, it’s using the standard G6 belt we see so often, along with a Duet3D mainboard, NEMA 17 steppers, and many 3D printed parts to hold its aluminum extrusions together. Thanks to that printer-inspired motion system, the ball can whirl around at 2000 mm/s, though [Mark] prefers to run slower: the demo video below shows operation at 1000 mm/s before the sand has been added.

This build was designed for ease of construction and movement: sized at 2’x4′ (about 61 cm x 122 cm), it fits through doors and fits an off-the-shelf slab of coffee table glass, something that [Mark] wishes he’d considered when building version two. That’s the nice thing about jumping in on a project someone’s been iterating for a while: you’ve got the benefit of learning from their mistakes. You can see the roots of this design, and what has changed, from the one he showed us in 2020. 

Naturally you’re not limited to CoreXY for a sand table, though it is increasingly popular — we’ve seen examples with polar mechanisms and even a SCARA arm.

Continue reading “The Zen Must Flow From Arrakis Sand Table”

Citizen Science By The Skin Of Your Teeth

If you are a schoolkid of the right age, you can’t wait to lose a baby tooth. In many cultures, there is a ritual surrounding it, like the tooth fairy, a mouse who trades your tooth for a gift, or burying the tooth somewhere significant. But in 1958, a husband and wife team of physicians wanted children’s teeth for a far different purpose: quantifying the effects of nuclear weapons testing on the human body.

A young citizen scientist (State Historical Society of Missouri)

Louise and Eric Reiss, along with some other scientists, worked with Saint Louis University and the Washington School of Dental Medicine to collect and study children’s discarded teeth. They were looking for strontium-90, a nasty byproduct of above-ground nuclear testing. Strontium is similar enough to calcium that consuming it in water and dairy products will leave the material in your bones, including your teeth.

The study took place in the St. Louis area, and the results helped convince John F. Kennedy to sign the Partial Nuclear Test Ban Treaty.

They hoped to gather 50,000 teeth in a year. By 1970, 12 years later, they had picked up over 320,000 donated teeth. While a few kids might have been driven by scientific altruism, it didn’t hurt that the program used colorful posters and promised each child a button to mark their participation.

Children’s teeth were particularly advantageous to use because they are growing and are known to readily absorb radioactive material, which can cause bone tumors.

Continue reading “Citizen Science By The Skin Of Your Teeth”

Heater Is Either A Miracle Or A Scam

[Big Clive] picked up a tiny heater for less than £8 from the usual sources. Would you be shocked to learn that its heating capacity wasn’t as advertised? No, we weren’t either. But [Clive] treats us to his usual fun teardown and analysis in the video below.

A simple test shows that the heater drew about 800 W for a moment and drops as it heats until it stabilizes at about 300 W. Despite that, these units are often touted as 800 W heaters with claims of heating up an entire house in minutes. Inside are a fan, a ceramic heater, and two PCBs.

The ceramic heaters are dwarfed by metal fins used as a heat exchanger. The display uses a clever series of touch sensors to save money on switches. The other board is what actually does the work.

[Clive] was, overall, impressed with the PCB. A triac runs the heaters and the fan. It also includes a thermistor for reading the temperature.

You can learn more about the power supply and how the heater measures up in the video. Suffice it to say, that a cheap heater acts like a cheap heater, although as cheap heaters go, this one is built well enough.

Continue reading “Heater Is Either A Miracle Or A Scam”

So Long Firefox, Hello Vivaldi

It’s been twenty-three years since the day Phoenix was released, the web browser that eventually became Firefox. I downloaded it on the first day and installed it on my trusty HP Omnibook 800 laptop, and until this year I’ve used it ever since. Yet after all this time, I’m ready to abandon it for another browser. In the previous article in this series I went into my concerns over the direction being taken by Mozilla with respect to their inclusion of AI features and my worries about privacy in Firefox, and I explained why a plurality of browser engines is important for the Web. Now it’s time to follow me on my search for a replacement, and you may be surprised by one aspect of my eventual choice.

Where Do I Go From Here?

Hackaday in the Ladybird browser
It’s Hackaday, in Ladybird! (Ooof, that font.)

Happily for my own purposes, there are a range of Firefox alternatives which fulfill my browser needs without AI cruft and while allowing me to be a little more at peace with my data security and privacy. There’s Chromium of course even if it’s still way too close to Google for my liking, and there are a host of open-source WebKit and Blink based browsers too numerous to name here.

In the Gecko world that should be an easier jump for a Firefox escapee there are also several choices, for example LibreWolf, and Waterfox. In terms of other browser engines there’s the extremely promising but still early in development Ladybird, and the more mature Servo, which though it is available as a no-frills browser, bills itself as an embedded browser engine. I have not considered some other projects that are either lightweight browser engines, or ones not under significant active development. Continue reading “So Long Firefox, Hello Vivaldi”

Simple Tricks To Make Your Python Code Faster

Python has become one of the most popular programming languages out there, particularly for beginners and those new to the hacker/maker world. Unfortunately, while it’s easy to  get something up and running in Python, it’s performance compared to other languages is generally lacking. Often, when starting out, we’re just happy to have our code run successfully. Eventually, though, performance always becomes a priority. When that happens for you, you might like to check out the nifty tips from [Evgenia Verbina] on how to make your Python code faster.

Many of the tricks are simple common sense. For example, it’s useful to avoid creating duplicates of large objects in memory, so altering an object instead of copying it can save a lot of processing time. Another easy win is using the Python math module instead of using the exponent (**) operator since math calls some C code that runs super fast. Others may be unfamiliar to new coders—like the benefits of using sets instead of lists for faster lookups, particularly when it comes to working with larger datasets. These sorts of efficiency gains might be merely useful, or they might be a critical part of making sure your project is actually practical and fit for purpose.

It’s worth looking over the whole list, even if you’re an intermediate coder. You might find some easy wins that drastically improve your code for minimal effort. We’ve explored similar tricks for speeding up code on embedded platforms like Arduino, too. If you’ve got your own nifty Python speed hacks, don’t hesitate to notify the tipsline!

Unusual Circuits In The Intel 386’s Standard Cell Logic

Intel’s 386 CPU is notable for being its first x86 CPU to use so-called standard cell logic, which swapped the taping out of individual transistors with wiring up standardized functional blocks. This way you only have to define specific gate types, latches and so on, after which a description of these blocks can be parsed and assembled by a computer into elements of a functioning application-specific integrated circuit (ASIC). This is standard procedure today with register-transfer level (RTL) descriptions being placed and routed for either an FPGA or ASIC target.

That said, [Ken Shirriff] found a few surprises in the 386’s die, some of which threw him for a loop. An intrinsic part of standard cells is that they’re arranged in rows and columns, with data channels between them where signal paths can be routed. The surprise here was finding a stray PMOS transistor right in the midst of one such data channel, which [Ken] speculates is a bug fix for one of the multiplexers. Back then regenerating the layout would have been rather expensive, so a manual fix like this would have made perfect sense. Consider it a bodge wire for ASICs.

Another oddity was an inverter that wasn’t an inverter, which turned out to be just two separate NMOS and PMOS transistors that looked to be wired up as an inverter, but seemed to actually there as part of a multiplexer. As it turns out, it’s hard to determine sometimes whether transistors are connected in these die teardowns, or whether there’s a gap between them, or just an artifact of the light or the etching process.

The AirPort Express Still Works In 2025 Thanks To Apple’s Ongoing Support

Apple was all-in on WiFi from the beginning, launching the AirPort line of products to much fanfare in 1999. In 2004, along came the AirPort Express—a fully-functional router the size of a laptop charger, that offered audio streaming to boot. As [schvabek] found out that while a lot of older Apple gear has long ago been deprecated, the AirPort Express is still very much supported and functional to this day!

Generally, you wouldn’t expect to plug in a 20-year-old Apple accessory and have it work with the company’s modern hardware. However, upon slotting the AirPort Express into a wall socket and starting the initialization process, [schvabek] noted that it was detected perfectly well by his post-2020 Macs. Only, there was a small problem—the configuration process would always stall out before completion.

Thankfully, there was a simple remedy. [schvabek] found that he could connect to the AirPort Express with his classic white plastic MacBook and complete the process. From there, he was astonished that Apple’s servers let him pull down a firmware update for a device from 2004. After that upgrade, the AirPort Express was fully functional with all his modern Apple gear. He could readily stream audio from his iPhone and MacBooks with no compatibility issues whatsoever.

It’s nice to see Apple still supporting this ancient hardware to this day. It’s a nice contrast when companies like Sonos are more than happy to brick thousands of old devices just for the sake of progress. Continue reading “The AirPort Express Still Works In 2025 Thanks To Apple’s Ongoing Support”