Squish That Stack With Rampart

[P B Richards] and [Aaron Flin] were bemoaning the resource hunger of modern JavaScript environments and planned to produce a system that was much stingier with memory and CPU, that would fit better on lower-end platforms. Think Nginx, NodeJS, and your flavour of database and how much resource that all needs to run properly. Now try wedge that lot onto a Raspberry Pi Zero. Well, they did, creating Rampart: a JavaScript-based complete stack development environment.

The usual web applications have lots of tricks to optimise for speed, but according to the developers, Rampart is still pretty fast. Its reason for existence is purely about resource usage, and looking at a screen grab, the Rampart HTTP server weighs in at less than 10 MB of RAM. It appears to support a decent slew of technologies, such as HTTPS, WebSockets, SQL search, REDIS, as well as various utility and OS functions, so shouldn’t be so lightweight as to make developing non-trivial applications too much work. One interesting point they make is that in making Rampart so frugal when deployed onto modern server farms it could be rather efficient. Anyway, it may be worth a look if you have a reasonable application to wedge onto a small platform.

We’ve seen many JavaScript runtimes over the years, like¬†this recent effort, but there’s always room for one more.

Homebrew LED Bulbs Keep Your Circadian Rhythms Steady

There was a time when LED light bulbs were a premium product that commanded a premium price, mainly because of limited supply and the usual marketing tricks. But now is not that time, since you can pick up an LED bulb for a buck or two at pretty much any store. So why in the world would you go to the effort to make your own light bulb?

For [DiodeGoneWild], the answer is simple: it’s all about staying in rhythm. Circadian rhythm, that is. We all know how light toward the blue end of the spectrum is bad for our sleep cycle, since it convinces our lizard brain that dawn is at hand. But even if you pick an LED bulb with a warm, or reddish, color temperature, there’s still a lot of UV light being emitted thanks to the phosphor LEDs that are typically used in them.

[DiodeGoneWild]’s first attempt at a design, in the first video below, mostly avoids phosphor LEDs in favor of a mix of yellow, red, and yellow-green LEDs to get a warmer spectrum. He used the housing and base from an expired bulb to enclose his custom circular PCB, the fabrication of which using a hand drill as a lathe and a Dremel to machine concentric tracks in the cladding was a real treat. So was the power supply, for that matter — a dropping capacitor followed by a bridge rectifier and a filtering cap. We like the discharge resistors across the caps and the fusible resistor on the mains side — it’s nice to see safety factored in from the start. And what’s not to like about using a DVD as a makeshift spectroscope?

We see that [DiodeGoneWild] has just dropped a second design, this time in a much smaller bulb and with relatively more phosphor LEDs.

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Electroplated 3D Printed Sword: Shiny!

We all want to 3D print metals, but the equipment to do that is still beyond most home workshops. However, [HEN3DRIK] takes resin 3D-printed items and electroplates them. Might not be as good as printing in metal, but it sure looks metallic. As you can see in the video below, the sword looks like it was crafted from highly-polished steel.

The sword comes out in four pieces. He repeats several times that sanding is the key because you must have flat surfaces. Using sandpaper and steel wool, he worked the parts to a fine finish. The parts assemble along an M8 threaded rod to form a whole. The next step was to electroplate with copper.

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Racing Cars On A PCB

Carl Friedrich Gauss was, to put it mildly, a polymath responsible for a large percentage of the things we take for granted in the modern world. As a physicist and mathematician he pioneered several fields of study including within the field of magnetism. But since he died decades before the first car was built, it’s unlikely he could have imagined this creation, a magnetic slot-car race track called the Gauss Speedway by [Jeff McBride], which bears the name of the famous scientist.

The Gauss Speedway takes its inspiration from a recent development in robotics, where many small robots can travel around a large area with the help of circuit traces integrated into their operating area. With the right current applied to these traces, magnetic fields are generated which propel the robots. [Jeff] wanted to build something similar, integrated into a printed circuit board directly, and came up with the slot car idea. The small cars have tiny magnets in them which interact with the traces in the PCB, allowing the cars to move with high precision around the track. He did abandon the traditional slot car controller in favor of a push-button style one directly on the PCB too, which means everything is completely integrated.

While this was more of a demonstration or proof-of-concept, some of the features of this style of robot can be seen in this video, which shows them moving extremely rapidly with high precision, on uneven surfaces, or even up walls. Magnetic robots like these are seeing quite a renaissance, and we’ve even seen some that use magnetism to shape-shift.

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IRL minesweeper render showing game on top of a campaign map

Meat-Space Minesweeper Game Hits The Mark

Hackers of a certain age will remember that before the Internet was available to distract us from our work, we had to find our own fun. Luckily, Windows was there to come to our aid, in the shape of “Minesweeper” – a classic of the age that involved figuring out/occasionally just guessing where a selection of mines had been hidden on a grid of squares via numerical clues to their proximity. For those missing such simple times, [Martin] has brought the game into physical space with his 3D-printed travel-game version.

GIF showing how to play IRL minesweeper game

A number of pre-determined game fields can be inserted (by a friend… or enemy, we presume!) and covered by tiles, which the mine-clearing player can then remove with their plastic shovel to reveal the clues. The aim of the game is to avoid uncovering a bomb, and to place flags where the bombs are hiding.

Aficionados of the game may remember that a little guessing was often inevitable, which sometimes ended in disaster. On the computer version, this merely entailed clicking the Smiley Face button for a new game, but in this case would require a new sheet to be inserted. Blank sheet templates are included for producing your own fiendish bomb-sites, and all the pieces pack away neatly into a handy clam-shell design that would be ideal for long car journeys when the data package on the kids’ tablets has run out.

We wonder what other classic games may lend themselves to a travel remake and look forward to the first 3D-printed travel set of Doom with anticipation!

If you’re above solving your own Minesweeper games, then you can learn how to write a solver in Java here. Continue reading “Meat-Space Minesweeper Game Hits The Mark”

Weasley Clock For Magically Low Cost

For those unfamiliar with the details of the expansive work of fiction of Harry Potter, it did introduce a few ideas that have really stuck in the collective conscious. Besides containing one of the few instances of time travel done properly and introducing a fairly comprehensive magical physics system, the one thing specifically that seems to have had the most impact around here is the Weasley family clock, which shows the location of several of the characters. We’ve seen these built before in non-magical ways, but this latest build seeks to drop the price tag on one substantially.

To do this, the build relies on several low-cost cloud computing solutions and smartphone apps to solve the location-finding problem. The app is called OwnTracks and is an open-source location tracker which can report data to any of a number of services. [Simon] sends the MQTT data to a cloud-based solution called HiveMQCloud, but you could send it anywhere in principle. With the location tracking handled, he turns to some very low-cost Arduinos to control the stepper motors which point the clock hands to the correct locations on the face.

While the build does rely on a 3D printer for some of the internal workings of the clock, this does bring the cost down substantially when compared to other options. Especially when compared to this Weasley family clock which was built into a much larger piece of timekeeping equipment, having an option for a lower-cost location-tracking clock face like this one is certainly welcome.

It’s MacOS. On An Unmodified Wii!

We’re used to the so-called “Hackintoshes”, non-Apple hardware running MacOS. One we featured recently was even built into the case of a Nintendo Wii. But [Dandu] has gone one better than that, by running MacOS on an unmodified Wii, original Nintendo hardware (French, Google Translate link).

How has this seemingly impossible task been achieved? Seasoned Mac enthusiasts will remember the days when Apple machines used PowerPC processors, and the Wii uses a PowerPC chip that’s a close cousin of those used in the Mac G3 series of computers. Since the Wii can run a Linux-based OS, it can therefore run Mac-on-Linux, providing in theory an environment in which it can host one of the PowerPC versions of MacOS.

The installation sequence has more than its share of difficulties, but eventually he was able to get the Wii running MacOS 9, the last classic MacOS. It runs DOOM, Internet Explorer 5, and iTunes even on these limited resources, though the last package had display and sound issues. He then tries a MacOS X build, but without success.

It’s fair to say that this is not exactly a way to get your hands on a cheap Mac, and remains more of an exercise in pushing a console beyond its original function. But it’s still an interesting diversion, and maybe someone will in time make a MacOS X version work on the Wii too. If you’re curious about the Mac-in-a-Wii that inspired this work, you can see it here.