24 | November | 2022

by Arthur · November 24, 2022

Carl Friedrich Gauss was, to say the least, a polymath who was 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 magnetism. But since he died decades before the first car was built, it is unlikely that he could have envisioned this creation, a magnetic streetcar racetrack named the Gauss Speedway by [Jeff McBride]which bears the name of the famous scientist.

Gauss Speedway takes its inspiration from a recent development in robotics, where many small robots can travel around a large area using circuit tracks integrated into their area of operation. With the right current applied to these tracks, magnetic fields are generated that drive the robots. [Jeff] wanted to build something similar, integrated into a printed circuit board directly, and came up with the idea of a slot machine. The small cars have tiny magnets in them that interact with the tracks in the PCB, allowing the cars to move with high precision around the track. He ditched the traditional slot controller in favor of a push button style direct on PCB too, meaning everything is fully integrated.

Although 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 fast with high precision, on uneven surfaces or even up walls. Magnetic robots like these are having quite a renaissance, and we’ve even seen some using magnetism to change shape.

Continue reading “Race cars on a PCB” →

IRL minesweeper rendering showing the game on top of a campaign map

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. Fortunately, Windows was there to help us, in the form of “Minesweepers” – a classic from the era 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 who miss such simple times, [Martin] has brought the game into the physical space with its 3D printed travel game version.

GIF showing how to play IRL minesweeper game

A number of pre-determined playing fields can be entered (by a friend…or enemy, we guess!) and covered in tiles, which the demining player can then remove with the 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.

Fans of the game may recall that a bit of guesswork was often unavoidable, sometimes ending in disaster. On the computer version this involved simply clicking the Smiley Face button for a new game, but in this case it would require a new sheet to be inserted. Blank sheet templates are included to make your own devil bomb pages, and all the pieces pack neatly into a handy clamshell design that would be ideal for long car trips when the data pack on your kids’ tablet is empty.

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

If you’re over solving your own Minesweeper games, learn how to write a solver in Java here. Continue reading “Meat-Space Minesweeper game hits the mark” →

For those unfamiliar with the details of the expansive fictional work of Harry Potter, it introduced some ideas that have truly stuck in the collective consciousness. Besides featuring one of the few instances of time travel done right and introducing a fairly comprehensive magical physics system, the one thing that seems to have made the biggest impact 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 tries to reduce the price tag on one considerably.

To do this, the building relies on several low-cost cloud computing solutions and smartphone apps to solve the problem of location. The app is called OwnTracks and is an open source location tracker that can report data to a variety of services. [Simon] sends the MQTT data to a cloud-based solution called HiveMQCloud, but you can send it anywhere in principle. With the position tracking handled, he turns to some very inexpensive Arduinos to control the stepper motors that point the watch to the right places on the face.

Although the construction relies on a 3D printer for some of the watch’s internal functions, this significantly reduces costs compared to other options. Especially compared to this Weasley family watch which was built into a much larger piece of timekeeping equipment, having an option for a more affordable location tracking watch face like this is certainly welcome.

We are 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, running MacOS on an unmodified Wii, original Nintendo hardware (French, Google Translate link).

How has this seemingly impossible task been accomplished? Seasoned Mac enthusiasts will remember the days when Apple computers used PowerPC processors, and the Wii uses a PowerPC chip that is a close cousin to the ones 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 where it can host one of the PowerPC versions of MacOS.

The installation sequence has more than its share of difficulties, but in the end he was able to get the Wii running MacOS 9, the latest classic MacOS. It runs DOOM, Internet Explorer 5 and iTunes even on these limited resources, although the latter package had display and sound issues. He then tries a MacOS X build, but to no avail.

It’s fair to say that this isn’t exactly a way to get 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 in time someone will get a MacOS X version working on the Wii as well. If you’re curious about the Mac-in-a-Wii that inspired this work, you can see it here.

The war against internet ads rages on, as the arms race between ad blockers and ad creators continues to escalate. To make a modern Internet experience even very palatable, many people use DNS-level filters to prevent ads from entering the network at all. However, this solution is not without collateral damage, as the available blacklists sometimes filter out something that should have made it to the user. For these emergencies, [Kristopher] created the Pie Stop, a physical button to perform a temporary passthrough on his Pi-Hole.

While [Kristopher] is able to recognize a problem and create the appropriate whitelist for some of these events, others in his household do not find this task as easy. When he is not around to fix the problems, this emergency stop can be pressed by anyone to temporarily stop DNS filtering and allow all traffic to pass through the network. It is based on the ESP-01S, a smaller ESP8266 board with only two GPIO pins. When pressed, it sends a custom command to Pi-Hole to disable ad blocking. A battery inside the cover means that it can be placed practically anywhere near anyone who might need it.

With this button deployed, network errors can be effectively prevented even with the most aggressive ad blocking at the DNS level. If you haven’t thought about deploying one of these on your own network, they’re hard to live without once you see how powerful they are. Take a look at this one which also catches spam.