Computer Logic Spins With No Electricity

January 21, 2024 by Al Williams 21 Comments

We’ve often said you can make a logic gate out of darn near anything. [The Action Lab] agrees and just released a video showing how he made some logic gates from chains and gears. Along the way, he makes the case that the moving chain is an analog for electric current. The demonstration uses a commercial toy known as Spintronics, but if you are mechanically handy, you could probably devise your own setup using 3D printing or gears.

A spring wound motor is a “battery.” Gears act like resistors and junctions to distribute “current” in multiple directions. Seeing series and parallel resistance as moving chains is pretty entertaining and might help someone new learn those concepts.

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Learn Sailing Mechanics Without Leaving Dry Land

January 20, 2024 by Danie Conradie 31 Comments

The ancient art of sailing can be very intimidating for the uninitiated given the shifty nature of wind. To help understand the interaction of wind direction and board orientation, [KifS] designed a hands-on sailing demonstrator that lets students grasp the basics before setting foot on a real sailboat.

The demonstrator uses a potentiometer as a tiller to control a model sailboat’s angle, while another stepper motor adjusts the position of a fan to simulate changing wind directions. With an Arduino Uno controlling everything, this setup affords students the opportunity to learn about sail positioning and adjusting to shifting winds in an interactive way, without the pressures and variables of being on the water.

[KifS]’s creation isn’t just about static demonstrations. It features four modes that progressively challenge learners—from simply getting a feel for the tiller, to adjusting sails with dynamic wind changes, even adding a game element that introduces random wind movements demanding quick adjustments. [KifS] mentions there are potentials aspects that can be refined, like more realistic sail response and usability, but it already achieved the main project goals.

There are a myriad of potential ways to add new tech to the ancient art of sailing. We’ve seen a DIY autopilot system, full sensor arrays, and an open source chart plotter. It’s even been proven you can have a wind powered land vehicle that travels faster than the wind.

The Giant LEGO You Always Wanted To Play With

January 20, 2024 by Jenny List 18 Comments

The interlocking LEGO bricks are probably one of the most versatile toys to come out of the 20th century, but aside from the Duplo larger-sized version for smaller kids, they don’t come in what you might term grown-up sizes. This has not deterred [Veranda Vikings] though, who have come up with the fantastic idea of giant LEGO bricks made from snow.

Making them is simplicity itself given enough depth of the white stuff, simply press the lid of one of those plastic LEGO storage bins into some fresh snowfall hard enough to compact your brick, and then lift clear a perfect icy 2 by 2 brick. Most of the post is devoted to the building escapades of some very happy kids, and we can’t help envying them the opportunity. It appears that like the LEGO fries in the cafe at Legoland in Bilund, these bricks don’t quite interlock. We think that it would be possible to press the LEGO storage lid into the bottom of them though, perhaps some readers would like to experiment.

Either way, this is a hack to warm the hearts of readers worldwide, whether they live in a country with snow or not. We’re surprised Lego themselves haven’t caught on to the idea, and sold giant snow-brick moulds.

Countdown To A Spaceship Simulator

January 16, 2024 by Richard Baguley 4 Comments

[Jon Petter Skagmo] claims that the spaceship simulator he’s working on is for his daughter, but we think there’s an excellent chance he’s looking to fulfill a few childhood dreams of his own. But no matter what generation ends up getting the most enjoyment out of it, there’s no question it’s an impressive build so far, complete with a very realistic-looking instrument display and joystick.

This is only the first in a series of builds, but our inner child is already intensely jealous. So far, [Jon] has built the instrument panel and controller that lights all buttons and runs the displays, which shows telemetry from a Falcon 9 launch. The video below goes into a lot of detail about how he built this SPI-driven instrument panel and why he made the whole thing modular, so it can be easily expanded without turning into a spaghetti-like mess.

It’s a great intro to thinking before you build, showing how he planned and built the system for maximum expandability and flexibility. Before the end, we wouldn’t surprised if he’s got quite a Kerbal Space Program controller on his hands for when the kid goes to bed.

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Sound-Reactive Light Saber Flips Allegiance Via Vowel Sounds

December 29, 2023 by Donald Papp 4 Comments

Students [Berk Gokmen] and [Justin Green] developed an RP2040-based LED-illuminated lightsaber as a final project with a bit of a twist. It has two unusual sound-reactive modes: disco mode, and vowel detection mode.

Switching allegiances (or saber color, at least) is only a sound away.

Disco mode alters the color of the saber dynamically in response to incoming sounds. Color and brightness are altered in response to incoming frequencies picked up by the on-board microphone, making a dynamic light show that responds particularly well to music.

The second mode is vowel detection, and changes the lightsaber’s color depending on spoken sounds. The “ee” sound makes the saber red, and the “ah” sound turns it blue. This method requires a lot of processing and filtering, and in the end it works, but is quite dependent on individual speakers for calibration.

The sound functionality centers around FFTs (Fast Fourier Transforms) which are fundamental to processing signals like audio in a meaningful way, and is a method accessible to embedded devices like microcontrollers with ADCs.

The lightsaber is battery-powered and wireless, and there are loads of details about the finer points of the design (including challenges and tradeoffs) on the project page, and the source code is available on GitHub. A video demonstration and walkthrough is embedded below.

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Building A Rad Super Capacitor RC Plane

December 25, 2023 by Lewin Day 15 Comments

[Tom Stanton] is a fan of things like rubber band planes, and has built many of his own air-powered models over the years. Now, he’s built a model powered by a supercapacitor for a thoroughly modern twist on stored-energy flying toys.

It’s not a wholly original idea; [Tom] was inspired by a toy he bought off-the-shelf. His idea, though, was to make one that could be hand-cranked to charge it to make it more like the rubber-band planes of old. He thus built his own geared generator for the job using a big pile of magnets and 3D printed components. It’s capable of putting out around 17 volts when cranked at a reasonable speed. Hooked up to the toy plane, his hand-crank generator was able to fully charge the plane in just a few turns.

His generator was really overkill for the small toy, though. Thus, he elected to build himself a much larger supercapacitor-powered model. He wired up a pack of six supercapacitors in series, designed for roughly 18 volts. The pack was given balance leads to ensure that no individual capacitor was charged beyond its 3.0 V rating. The pack was placed inside a nice aerodynamic printed fuselage. The plane was then given a brushless motor and prop, speed controller, servos, and an RC receiver. Indeed, far from a simple throwable model, it’s a fully flyable RC plane.

The plane is quite a capable flyer with plenty of power, but a fairly short run time of just under two minutes. Though, with that said, it can be recharged in just about that same amount of time thanks to its supercapacitor power supply. [Tom] reckons it should be capable of a 1:1 crank time to flight time ratio in ideal conditions.

Supercapacitors are super cool, but we don’t see enough of them. They’ve popped up here and there, and obviously have many important applications, but we’re not sure they’ve had a real killer app in the consumer space. XV Racers were killer fun, though. Continue reading “Building A Rad Super Capacitor RC Plane” →

A hand holds a LEGO replica of a Polaroid camera. The back of the "camera" has been removed to show the sereies of Technic pieces inside that allow the camera shutter to work.

How A LEGO Set Is Born

December 19, 2023 by Navarre Bartz 11 Comments

LEGOs are the first window into making something in your head become real for many makers. The Verge dug into how a LEGO set itself goes from idea to the shelves.

While most sets come from the minds of LEGO designers, since 2008, fans can submit their own sets to LEGO Ideas for the chance to become a real product. In this case, we follow the journey of [Marc Corfmat]’s Polaroid OneStep Camera from his initial attempts at LEGO stardom with his brother [Nick] to the current set that took off.

While the initial idea and build are the seed for a new set, once the project is in the hands of LEGO, designers meticulously make revision after revision to ensure the set is enjoyable to build and any moving parts continue to function for thousands of cycles. This is all weighed against the total cost of the BOM as well as any licensing required for intellectual property. One particularly interesting part of the article is how designers at LEGO are afforded a certain number of “frames” for custom bricks which leads to some interesting hacks and collaboration as all good constraints do.

For more LEGO hacks, checkout LEGO’s long lost cousin, testing LEGO-compatible axle materials, or these giant LEGO-like pieces.