A Digital Replacement For Your Magic Eye

September 2, 2024 by Zoe Skyforest 20 Comments

Magic Eye tubes were popular as tuning guides on old-school radio gear. However, the tubes, the 6U5 model in particular, have become rare and remarkably hard to come by of late. When the supply dried up, [Bjørner Sandom] decided to build a digital alternative instead.

The build relies on a small round IPS display, measuring an inch in diameter and with a resolution of 128×115 pixels. One can only presume it’s round but not perfectly so. It was then fitted with a 25mm glass lens in order to give it a richer, deeper look more akin to a real Magic Eye tube. In any case, a STM32F103CBT was selected to drive the display, with the 32-bit ARM processor running at a lovely 72 MHz for fast and smooth updates of the screen.

The screen, controller, and supporting circuitry are all built onto a pair of PCBs and installed in a 3D-printed housing that lives atop a tube base. The idea is that the build is a direct replacement for a real 6U5 tube. The STM32 controller receives the automatic gain control voltage from the radio set it’s installed in, and then drives the screen to behave as a real 6U5 tube would under those conditions.

By virtue of the smart design, smooth updates, and that nifty glass lens, the final product is quite a thing to behold. It really does look quite similar to the genuine article. If you’ve got a beloved old set with a beleagured magic eye, you might find this a project worth replicating. Video after the break.

Continue reading “A Digital Replacement For Your Magic Eye” →

Reconfigurable Tracked Robot Has Some Neat Flexible Abilities

August 29, 2024 by Zoe Skyforest 9 Comments

When you think of tracked robots, you might think of bomb disposal robots or others used in military applications. You probably haven’t seen anything quite like this, however—it’s a “reconfigurable continuous track robot” from researchers [Tal Kislasi] and [David Zarrouk (via IEEE Spectrum).

The robot looks simple, like some kind of tracked worm. As its motors turn, the track moves along as you would expect, propelling the robot along the ground. Its special feature, though, is that the track can bend itself up and down, just like a snake might as it rises up to survey a given area.

The little tracked robot can thus tilt itself up to climb steps, and even bend itself over small obstacles. It can even try and hold itself up high as it inches along to try and bridge its way over a gap.

The robot can selectively lock each link (or not) as it passes by.

How does it achieve this? Well, the robot is able to selectively lock the individual links of its outer track in various orientations. As the links pass over the front of the robot, a small actuator is used to lock each link in a 20-degree orientation, or a straight orientation, or leave them loose.

The ability to lock multiple links into a continuous rigid structure allows the robot to rise up from the ground, form itself into a stiff beam, or conform to the ground as desired. A mechanism at the back of the robot unlatches the links as they pass by so the robot retains flexibility as it moves along.

It’s a nifty design, and one we’d like to see implemented on a more advanced tracked robot. We’ve explained the benefits of tracked drivetrains before, too.

Continue reading “Reconfigurable Tracked Robot Has Some Neat Flexible Abilities” →

The Commodordion Gets A Big Usability Upgrade

August 28, 2024 by Zoe Skyforest 13 Comments

The chiptune scene is dominated by Game Boys and other Nintendo hardware, but one should never forget the gorgeous, beautiful tones that come from the hallowed Commodore 64. [Linus Åkesson] knows this well, and it’s at the heart of his work on the Commodordion. Now, he’s built an even better version.

The original idea he had was to build an accordion-like control surface for the SID chip in a Commodore 64. The device is capable of creating beautiful accordion-like music with a simple 8-bit flair. He has since dubbed the original Commodordion the “bass Commodordion,” while the new version is classified as a tenor instrument.

The prime upgrades are ergonomic. The previous instrument was too heavy, with the left hand having to carry an entire Commodore 64 on its own. It was also hard to reach the keys. The new version is much lighter, with one of the two C64s of the original having been removed. The supporting electronics have been redesigned to more neatly fit into a space behind the bellows.

The result is a machine that’s far easier to play, and one that won’t injure the user in extended play sessions. “It’s now a pleasure, not a pain,” says [Linus]. The payoff in usability is obvious, and the tunes themselves are hauntingly beautiful.

We first covered the Commordordion back in 2022, but it wasn’t the first time we saw one of [Linus]’s impressive creations.

Continue reading “The Commodordion Gets A Big Usability Upgrade” →

Why Use A Sensor When A Pseudo-Sensor Will Do?

August 28, 2024 by Zoe Skyforest 30 Comments

Usually, when you need to sense something in a project, the answers are straightforward. Want to sense air temperature? There’s a sensor for that. Particulate content in the air? There’s a sensor for that, too. Someone sneaking up on you? Get yourself some passive infrared sensors (PIRs) and maybe a smart camera just to be sure.

But sometimes you can be sneaky instead, saving the cost of a sensor by using alternative techniques. Perhaps there’s a way to use the hardware you already have to determine what you need. Maybe you can use statistical methods to calculate the quantity you’re looking for from other measurements.

Today, we’ll examine a great example of a “pseudo-sensor” build in an existing commercial device, and examine how these techniques are often put to good use in industry.

Continue reading “Why Use A Sensor When A Pseudo-Sensor Will Do?” →

Proper Mag Lev Controller Makes Snail Lamp Much Cooler

August 28, 2024 by Zoe Skyforest 5 Comments

Magnetic levitation has not quite revolutionized the world of transit the way some of us might have hoped. It has, however, proven useful to [mrdiytechmagic], who has put the technology to grand use in making his levitating snail lamp.

The build is actually relatively complicated compared to some levitating toys you might have seen before. It uses a number of coils to produce a magnetic field to levitate the 3D printed plastic snail which contains the lighting element itself.

The actively controlled levitation base uses a magnetic sensor to detect the changing field as the snail moves above it. It then varies the current going to the various coils to keep the snail balanced and in place. Power is transmitted with a further larger coil, much as in a wireless phone charger. This is picked up by a circuit in the snail, and used to power the LEDs inside.

It might not have been our first choice, but having seen it in action, we can’t deny a levitating 3D printed snail is pretty impressive. If you’d prefer something slightly more befitting such a high-tech looking presentation, perhaps a hovering SpaceX Starship would be more your speed.

Continue reading “Proper Mag Lev Controller Makes Snail Lamp Much Cooler” →

Building A Small Gyro Stabilized Monorail

August 27, 2024 by Zoe Skyforest 12 Comments

Monorails aren’t just the core reason why The Simpsons remains on air after thirty-six seasons, twenty-six of which are unredeemable garbage. They’re also an interesting example of oddball rail travel which has never really caught on beyond the odd gadgetbahn project here and there. [Hyperspace Pirate] recently decided to investigate the most interesting kind of monorail of all—the gyro stabilized type—on a small scale for our viewing pleasure.

The idea of a gyro-stabilized monorail is to use active stability systems to allow a train to balance on a single very thin rail. The benefits of this are questionable; one ends up with an incredibly expensive and complex rail vehicle that must always run perfectly or else it will tip over. However, it is charming to watch in action.

[Hyperspace Pirate] explains how the monorail vehicle uses control moment gyroscopes to keep itself upright. The video also explains the more common concept of reaction wheels so the two systems can be contrasted and compared. It all culminates in a wonderful practical demonstration with a small 3D printed version of a 20th-century gyro monorail running on a 24″ track.

If you’re studying mechanical engineering this is a great project to pore over to see theoretical principles put into obvious practice. Video after the break.

Continue reading “Building A Small Gyro Stabilized Monorail” →

Using The Pi Pico As ‘Programmable Hardware’ For The Apple II

August 27, 2024 by Zoe Skyforest 7 Comments

When we think of programmable hardware, we think of FPGAs. But they’re not the only option. [Oliver Schmidt] has been exploring how the Raspberry Pi Pico can serve in such a role for the classic Apple II. The talk was presented at the KansasFest event this year, and it’s well worth diving into!

[Oliver] has developed A2Pico. It’s a series of Apple II peripheral cards that are based around the Raspberry Pi Pico, as you might have guessed. [Oliver] has been working in the area since 2021 with one [Glenn Jones], with the duo experimenting with connecting the versatile microcontroller directly to the slot bus of the Apple II. [Ralle Palaveev] then chimed in, developing the A2Pico hardware with solely through-hole components for ease of assembly.

A number of cards have been developed based on A2Pico, including a storage device, a Z80 CP/M card, and a specialized card to play Bad Apple on the IIGS. It’s all thanks to the versatility of the programmable I/O (PIO) peripheral inside the Raspberry Pi Pico. This device enables the Pico to be reprogrammed to handle all sorts of complicated tasks at great speed. This is particularly useful when using it to bit-bang a protocol or talk with another machine, and it serves perfectly well in this role. Basically, by reprogramming the Pico and its PIO, the A2Pico design can become any one of a number of different add-on cards.

It’s well worth diving into this stuff if you’ve ever contemplated building your own peripheral cards for 8-bit and 16-bit machines. We’ve seen some other great add-on cards for vintage machines before, too.

Continue reading “Using The Pi Pico As ‘Programmable Hardware’ For The Apple II” →