The Flight Of The Dremel

January 5, 2023 by 12 Comments

A few months ago we featured a model aircraft whose power plant came courtesy of an angle grinder. It was the work of [Peter Sripol], and it seems he was beseiged by suggestions afterwards that he might follow it up with a helicopter built using a Dremel rotary tool. Which he duly did, and the results can be seen in the video below the break.

The Dremel itself requires a gearing to drive the balsa-bladed rotor, and a tail rotor is mounted with its own motor at the end of a boom. The video has many entertaining failures which see him arrive at a set of balancing arms and a tailplane for stability. The result is a helicopter that flies after a fashion, and is even able to stay aloft for a few seconds rather than crashing to earth.

The machine lacks the full rotor pitch control of its commercial bretheren, indeed the only control is directional via the tail rotor. Still it deserves top marks for entertainment alone, and we wouldn’t mind a go ourselves. The original angle grinder craft can be seen here.

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A White-Light Laser, On The Cheap

January 4, 2023 by 51 Comments

Lasers are known for the monochromatic nature of their light, so much so that you might never have thought there could be such a thing as a white laser. But in the weird world of physics, a lot of things that seem impossible aren’t really, as demonstrated by this dirt-cheap supercontinuum laser.

Of course, we’re not experts on lasers, and certainly not on non-linear optics, so we’ll rely on [Les Wright]’s video below to explain what’s going on here. Basically, a “supercontinuum” is just the conversion of a monochromatic source to a broader spectral bandwidth. It’s a non-linear optical process that’s usually accomplished with expensive bits of kit, like photonic crystal fibers, which are optical fibers with an array of tiny air-filled holes running down their lengths. Blast a high-intensity monochromatic laser down one end, and white light comes out the other end.

Such fibers are obviously fantastically expensive, so [Les] looked back in the literature and found that a simple silica glass single-mode fiber could be used to produce a supercontinuum. As luck would have it, he had been experimenting with telecom fibers recently, so along with a nitrogen laser he recovered from a Dumpster, he had pretty much everything he needed. The final setup uses the UV laser to pump a stilbene dye laser, which shoots a powerful pulse of 426 nanometer light into about 200 meters of fiber, and produces a gorgeous supercontinuum containing light from 430 nm to 670 nm — pretty much the entire visible spectrum.

It’s great to see projects like this that leverage low-cost, easy-to-source equipment to explore esoteric physics concepts.

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Stewart Platform Keeps Its Eye On The Ball

January 4, 2023 by 4 Comments

Although billed as a balancing robot, [Aaed Musa’s] robot doesn’t balance itself. It balances a ball on a platform. You might recognize this as something called a Stewart platform, and they are great fun at parties if you happen to party with a bunch of automation-loving hackers, that is. Take a look at the video below to see the device in action.

If you want to duplicate the project, there’s a bit of expense, but the idea behind it is explained in the video. Much of the robot is 3D printed with threaded inserts. Even the ball is 3D printed in two parts along with a cubic connector to hold the two hemispheres together. The acrylic platform was cut with a water jet, although you could just as easily have cut it with hand tools.

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Zen And Glowing Air Bubble Displays

January 4, 2023 by 10 Comments

When you work in a medium for long enough, and you learn how it works more and more deeply, you eventually become its master. [Yukio Shinoda] is probably master of the LED bubble display.

She started out with an idea, back in 1994, of a column of water and an array of solenoids to inject air, making patterns in the bubbles. Time passed, and she began to realize these works, first in water and then switching over to glycerine for slower, more predictable, and more spherical bubbles. The latest version realizes her initial vision, after 29 years, with an 8×8 array of nozzles making 3D shapes in the slowly rising columns. Continue reading “Zen And Glowing Air Bubble Displays” →

An Epic Quest To Build The Ultimate Game Boy

January 4, 2023 by 8 Comments

If you didn’t grow up clutching Nintendo’s original DMG-01 Game Boy, it might difficult to see the appeal in 2023. It had the ergonomics of a brick, the system’s unlit LCD screen utilized a somewhat nauseating green color palette, and when compared to its contemporary competition like the Sega Game Gear or Atari Lynx, it would certainly appear to be the inferior platform. But despite its faults there was just something magical about the machine, and those who have a soft spot for the iconic handheld are always eager to relive those glory days.

Now, thanks to the incredible work of [Bucket Mouse], playing the old “brick” Game Boy doesn’t have to be nearly as austere an experience as it was in 1989. That’s because he’s developed a set of replacement PCBs for the handheld that not only implement all of the features of the later Game Boy Color, but sprinkle in some modern niceties as well. The result is a handheld that looks like the original on the outside, but plays all your favorite games even better than you remember them. Continue reading “An Epic Quest To Build The Ultimate Game Boy” →

Machine Learning Makes Sure Your LOLs Are Genuine

January 4, 2023 by 13 Comments

There was a time not too long ago when “LOL” actually meant something online. If someone went through the trouble of putting LOL into an email or text, you could be sure they were actually LOL-ing while they were typing — it was part of the social compact that made the Internet such a wholesome and inviting place. But no more — LOL has been reduced to a mere punctuation mark, with no guarantee that the sender was actually laughing, chuckling, chortling, or even snickering. What have we become?

To put an end to this madness, [Brian Moore] has come up with the LOL verifier. Like darn near every project we see these days, it uses a machine learning algorithm — EdgeImpulse in this case. It detects a laugh by comparing audio input against an exhaustive model of [Brian]’s jocular outbursts — he says it took nearly three full minutes to collect the training set. A Teensy 4.1 takes care of HID duties; if a typed “LOL” correlates to some variety of laugh, the initialism is verified with a time and date stamp. If your LOL was judged insincere – well, that’s on you. See what you think of the short video below — we genuinely LOL’d. And while we’re looking forward to a ROTFL verifier, we’re not sure we want to see his take on LMAO.

Hats off to [Brian] for his attempt to enforce some kind of standards online. You may recall his earlier attempt to make leaving Zoom calls a little less awkward, which we also appreciate.

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Something’s Rotating In The State Of Denmark: A Clock

January 4, 2023 by 15 Comments

If you visit the Copenhagen City Hall, you’ll see an ornate mechanical clock. By itself, this is unremarkable, of course. There are plenty of ornate clocks in city halls around the world, but this one has a fascinating backstory that starts with a locksmith named Jan Jens Olsen. Unfortunately, Jens didn’t actually complete the clock before his death. It would take 12 years to put together the 15,448 individual parts. However, he did manage to see most of the clock that he had been designing for 50 years put together.

Jens was 60 when he started constructing the clock, but the story starts when he was only 25. In Strasbourg, the young locksmith saw an astronomical clock with a perpetual calendar in a cathedral. He was fascinated and returned several times to study the mechanism. Around the age of 30, Jens had moved to watchmaking and had a keen interest in astronomy — he was a founding member of the Danish Astronomical Society. Perhaps it was the combination of these two interests that made it inevitable that he would want to build a precise astronomically-correct clock.

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