Smartphone App Uses AR To Visualize The RF Spectrum

January 9, 2019 by Dan Maloney 21 Comments

Have you ever wished you could see in the RF part of the radio spectrum? While such a skill would probably make it hard to get a good night’s rest, it would at least allow you to instantly see dead spots in your WiFi coverage. Not a bad tradeoff.

Unwilling to go full [Geordi La Forge] to be able to visualize RF, [Ken Kawamoto] built the next best thing – an augmented-reality RF signal strength app for his smartphone. Built to aid in the repositioning of his router in the post-holiday cleanup, the app uses the Android ARCore framework to figure out where in the house the phone is and overlays a color-coded sphere representing sensor data onto the current camera image. The spheres persist in 3D space, leaving a trail of virtual breadcrumbs that map out the sensor data as you warwalk the house. The app also lets you map Bluetooth and LTE coverage, but RF isn’t its only input: if your phone is properly equipped, magnetic fields and barometric pressure can also be AR mapped. We found the Bluetooth demo in the video below particularly interesting; it’s amazing how much the signal is attenuated by a double layer of aluminum foil. [Ken] even came up with an Arduino with a gas sensor that talks to the phone and maps the atmosphere around the kitchen stove.

The app is called AR Sensor and is available on the Play Store, but you’ll need at least Android 8.0 to play. If your phone is behind the times like ours, you might have to settle for mapping your RF world the hard way.

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Glasses Frames Crafted Out Of Wood

January 9, 2019 by Lewin Day 10 Comments

Most glasses and sunglasses on the market make use of metal or plastic frames. It’s relatively easy to create all manner of interesting frame geometries, tolerances can be easily controlled for fitting optical elements, and they’re robust materials that can withstand daily use. Wood falls short on all of these measures, but that doesn’t mean you can’t use it to make a beautiful pair of glasses.

ZYLO is a company making wooden eyewear, and this video from [Paide] shows the build process in detail. Modern tools are used to make things as efficient as possible. Parts are lasercut and engraved to form the main part of the frames as well as the temples (the arms that sit over the ears to hold them on your face). A special jig is used to impart a curve on the laminated wood parts before further assembly is undertaken. Metal pre-fabricated hinges and screws are used to bolt everything together like most other modern sunglasses, but there’s significant hand finishing involved, including delicate inlays and highlighting logo features.

In contrast, Manuel Arroyave works very differently in the creation of his Cedoro glasses. Sheets are first laminated together, before the shape is roughed out by a special horizontal axis milling setup. Even small details like the hinges are delicately hand-crafted out of wood and fitted with tiny wooden dowels.

It goes to show that there’s always more than one way to get a job done. We’re tempted to break out the laser cutter and get started on some custom shades ourselves. Perhaps though, you’re too tired to put your sunglasses on by yourself? Nevermind, there’s a solution for that, too. Video after the break.

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The T-Pain Toy Is Now A Guitar Effect

January 9, 2019 by Lewin Day 8 Comments

T-Pain is rapper hailing from Florida, who made his name through creative use of the Autotune effect. Nobody quite does it like T-Pain to this day, but kids the world over got the chance with the release of the “I Am T-Pain” microphone, which puts effects on the user’s vocal to make them sound as fly as possible, batteries not included. In the spirit of musical exploration, [Simon] decided it would be interesting to turn the effect into a guitar pedal.

Initial plans were to wire the microphone to an input jack, and the speaker to an output jack, but things didn’t remain so simple. The toy comes with a line-in and a headphone jack already, but the wiring scheme is strange and one of the inputs can also act as an output under certain conditions. [Simon] took the kitchen sink approach, throwing a bunch of jacks at the circuit and putting it all in a pedal case with some knobs to twiddle some parameters.

The final result is a warbly, lo-fi vibrato when a guitar signal is fed in. It’s quite different from how the original toy sounds, but recalls us somewhat of the Anti-nautilus pedal when used in conjunction with a looper. Video after the break. Continue reading “The T-Pain Toy Is Now A Guitar Effect” →

Morse Code Keyboard 1939 Style!

January 9, 2019 by Al Williams 29 Comments

If you want to learn Morse code and you don’t have a teacher, you’d probably just head over to a website or download a phone app. Before that, you probably bought a cassette tape or a phonograph record. But how did you learn Morse if you didn’t have any of that and didn’t know anyone who could send you practice? Sure, you could listen to the radio, but in 1939 that might be difficult, especially to find people sending slow enough for you to copy.

Wireless World for August 3rd, 1939, has the answer in an article by [A. R. Knipe] on page 109. While you probably wouldn’t use it today, it is a great example of how ingenious you can be when you don’t have an Arduino and all the other accoutrements we take for granted today.

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Delta Robot Is Sorting Golf Balls And Taking Names

January 9, 2019 by Lewin Day 15 Comments

It’s a common situation faced by every hard-working American – you get home after a long day at the calcium mines, and find yourself stuck with a pile of colored golf balls that simply aren’t going to sort themselves. Finally, you can put away your sorting funnels and ball-handling gloves – [Anthony] has the solution.

That’s right – it’s a delta robot, tasked with the job of sorting golf balls by color. A Pixy2 object tracking camera is used to survey the table, with the delta arms twitching around to allow the camera to get an unobstructed view. Once the position of the balls is known, a bubble sort is run and the balls rearranged into their correct color order.

[Anthony] readily admits the bubble sort is very inefficient at this task; it was an intentional choice so it could be later compared with other sorting methods. [Anthony] also goes into detail, sharing the development process of the suction gripper as well as discussing damping methods to reduce noise.

Delta machines are always fun to watch, and are a good choice for sorting machines. We’ve seen some really tiny ones, too. Video after the break.

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Three Dimensions: What Does That Really Mean?

January 9, 2019 by Jenny List 51 Comments

The holy grail of display technology is to replicate what you see in the real world. This means video playback in 3D — but when it comes to displays, what is 3D anyway?

You don’t need me to tell you how far away we are from succeeding in replicating real life in a video display. Despite all the hype, there are only a couple of different approaches to faking those three-dimensions. Let’s take a look at what they are, and why they can call it 3D, but they’re not fooling us into believing we’re seeing real life… yet.

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New Game, Old Ways: Cramming An NES Game Into 40 KB

January 9, 2019 by Dan Maloney 27 Comments

Why would anyone bother to create new content for a console system that’s staring down its 40th birthday? Perhaps just for the challenge of fitting a game into 40 kilobytes of storage.

That at least seems to be the motivation behind [Morphcat Games] pending release of Micro Mages, a new game for the Nintendo Entertainment System console that takes its inspiration from Super Mario Bros. The interesting bit here is how they managed to stuff so much content into so little space. The video below goes into great detail on that, and it’s a fascinating lesson in optimization. The game logic itself is coded in assembler, which of course is far more efficient than higher level languages. Even so, that took 32 kB of ROM, leaving a mere 8 kB for background elements and foreground sprites.

Through a combination of limited sprite size, tiling of smaller sprites to make larger characters, and reusing tiles by flipping them horizontally or vertically, an impressively complete palette of animated characters was developed. Background elements were similarly deconstructed and reused, resulting in a palette of tiles used to generate all the maps for the game that takes up just 60 bytes. Turning those into playable levels involves more mirroring and some horizontal shifting of tiles, and it looks like quite an engaging playfield.

Yes, there’s a Kickstarter for the game, but we’re mainly intrigued by what it takes to cram a playable game into so little space. Don’t get us wrong – we love the Retro Pie builds too, but seeing the tricks that early game developers relied upon to make things work really gets the creative juices flowing.

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