Rock-A-Bye Baby, On The Mechatronic Crib Shaker

June 20, 2021 by Dan Maloney 13 Comments

While an engineering mindset is a valuable tool most of the time, there are some situations where it just seems to be a bad fit. Solving problems within the family unit would seem to be one such area, but then again, this self-rocking mechatronic crib seems to be just the cure for sleepytime woes.

From the look of [Peter]’s creation, this has less of a rocking motion and more of a gentle back-and-forth swaying. Its purpose is plainly evident to anyone who has ever had to rock a child to sleep: putting a little gentle motion into the mix can help settle down a restless infant pretty quickly. Keeping the right rhythm can be a problem, though, as can endurance when a particularly truculent toddler is fighting the urge to sleep. [Peter]’s solution is a frame of aluminum extrusion with some nice linear bearings oriented across the short axis of the crib, which sits atop the whole thing.

A recirculating ball lead screw — nothing but the best for [Junior] — and a stepper drive the crib back and forth. [Peter] took care to mechanically isolate the drivetrain from the bed, and with the selection of the drive electronics and power supply, to make sure that noise would be minimal. Although thinking about it, we’ve been lulled to sleep by the whining steppers of our 3D printer more than once. Or perhaps it was the fumes.

Hats off to [Peter] for a setup that’s sure to win back a little of the new parent’s most precious and elusive commodity: sleep.

Wood And Brass Drink Temperature Monitor Looks Good, Has Class

June 16, 2021 by Kristina Panos 7 Comments

We’ve all been there. Your current project has hit a wall, or the next step will take days to complete, and you need something to do in the meantime. So you start a project that you envision will fit nicely in the gap, and then, inevitably, it doesn’t. Maybe it even takes so long that the original project gets finished first. So what? There’s nothing wrong with that, especially when the filler project turns out as well as this drink temperature monitor disguised as a circuit sculpture (video, embedded below). Just put your mug on the coaster, and the weight of it activates a hidden switch, which causes the sculpture to display its secret LEDs.

[MakeFunStuff] wanted to make something that looked less like a circuit and more like art, while building a tool that could determine the relative hotness of a beverage. Such a a useful circuit sculpture sounds like a tall order to us, but [MakeFunStuff] pulled it off with finesse and style.

The circuit is based around this Sputnik-looking standalone IR temperature sensor which, as [MakeFunStuff] aptly describes, is “a single-pixel infrared camera that picks up everything in a 90° cone starting at the sensor.”

[MakeFunStuff] paired this easy-to-use sensor with an Arduino Nano and five LEDs that show how hot a beverage is on a scale from 1 to 5. The sensor is hidden in plain sight, suspended from the top of the brass rod sculpture and blending in perfectly. We love that the LEDs are hidden behind a thin layer of carefully-drilled wood and agree that a drill press would have been much easier.

The code is set up for just about every temperature scale from Celsius to Rømer, so that solves that argument. [MakeFunStuff] went with the Kelvin scale because science. Our favorite thing about this video is that [MakeFunStuff] shared their failures and fixes as they built their way toward answering the questions of how to suspend the sensor over the drink, and how best to display the heat level while hiding the electronics. Go grab a hot cup of something and check it out after the break while you let it cool off the normie way.

We admit that we would likely zone out while waiting for the LEDs to disappear. Here’s a smart coaster that uses an ESP8266 to send a message to Discord when your beverage has reached the perfect drinking temperature.

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Friendly Webcam Robot Keeps An Eye On Privacy

June 14, 2021 by Kristina Panos 8 Comments

Wouldn’t it be nice if every webcam had a hardware switch? Especially for those built-in webcams like the one in your laptop. Since they don’t have switches yet, we’re just stuck trying to remember to turn them off or re-apply the sticker after every meeting. [Becky Stern] was tired of trying to remember to blind the all-seeing eye, and decided to make a robot companion that would do it for her.

Essentially, a servo-driven, 3D-printed eyelid covers the eye’s iris and also the web cam directly underneath. At first, we though [Becky] had liberated the business parts of a cheap webcam and built it into the eyeball, but this is far less intrusive. The eyeball simply sits atop the monitor, and [Becky] can control the eyelid two ways: she can set a timer with the potentiometer to close it automatically after some number of minutes, or else do it on demand using the momentary button. We’d love to see it tied directly to Zoom and or whatever else [Becky] uses regularly. Be sure to check out the build and demo video after the break to see it in action.

We love this cute and friendly reminder that the camera could be watching us. It’s way less creepy than this realistic eyeball webcam that looks around and blinks.

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Teach Your Air Compressor To Blow Eggs

June 7, 2021 by Kristina Panos 16 Comments

As fun as it is to decorate Easter eggs, the road to a hollow hen’s egg is a gross and gooey avenue. Trust us, it sucks to blow out eggs, and it’s hard to get it right. Plus, you know, there’s that whole salmonella thing. [Phil] decided to speed things up this year by using an air compressor to do the dirty work.

Of course, one must approach this problem delicately because eggs are fragile. It would be nice to drill the egg instead of poking the end with a needle, but how are you gonna pull that off without breaking it? As it turns out, all you need is a bench vise, the right piece of PVC, a bit of rubber to keep the egg safe, and some hose clamps to keep the business part together.

[Phil] built a two-stage contraption that serves both purposes — the bottom cup safely cradles the egg for drilling, and the identical top cup connects to the air compressor, which blows the goo out of the bottom hole. [Phil] might have used negative pressure instead, but doesn’t have a vacuum pump or hose. Be sure to check out the brief demo video below.

Don’t want to mess around with real eggs? There are tons of ways to beautify fake eggs, but few of them are as cool as lasers.

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Anti-Gravity, Time Travel, And Teleportation: Dr. Hamming Gives Advice

June 1, 2021 by Al Williams 27 Comments

You may not know the name [Richard Hamming], but you definitely use some of his work. While working for Bell Labs, he developed Hamming codes — the parent of a class of codes that detect, and sometimes correct, errors in everything from error-correcting memory to hard drives. He also worked on the Manhattan Project and was a lecturer at the Naval Postgraduate school.

Turns out [Hamming] has an entire class from the 1990s on YouTube and if you are interested in coding theory or several other topics, you could do worse than watch some of them. However, those videos aren’t what attracted me to the lectures. As the last lecture of his course, [Hamming] used to give a talk called “You and Your Research” and you can see one of the times he delivered it in the video below. You might think that it won’t apply to you because you aren’t a professional academic or researcher, but don’t be too quick to judge.

Turns out, [Hamming’s] advice — even by his own admission — is pretty general purpose for your career or even your life. His premise: As far as we know, you have one life to live, so why shouldn’t it be a worthwhile one by your definition of worthwhile.

Along the way, he has an odd combination of personal philosophy, advice for approaching technical problems, and survival skills for working with others. If you are in the field, you’ll probably recognize at least some of the names he drops and you’ll find some of this technical advice useful. But even if you aren’t, you’ll come away with something. Some of it seems like common sense, but it is different, somehow, to hear it spoken out loud. For example:

If you don’t work on important problems, it’s not likely that you’ll do important work.

One piece of technical advice? Don’t waste time working on problems you have no way to attack. He points out that anti-gravity, time travel, and teleportation would be very lucrative. But why work on them when there appears to be no way to even remotely accomplish them today. Well, at least when he said that. There has been a little progress on a form of teleportation, but that wasn’t what he was talking about anyway.

While not a hack in the traditional sense, examining your life, career, and technical research to improve your own effectiveness is something to take seriously. We were hoping he would throw in a joke about error-correcting your career, but unless we blinked, no such luck.

Hamming’s work on block codes was followed about ten years later by the Reed-Solomon code which is found nearly everywhere now. Hamming is also associated with the term “hamming distance,” something we talked about when discussing Gray code.

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Small Swedish Stores Are Miniature Oases In A National Food Desert

May 30, 2021 by Kristina Panos 47 Comments

It all started one night in 2016 after [Robert Ilijason] dropped the last remaining jar of baby food in the house, breaking it. On the 20-minute drive to the nearest supermarket, he had an idea: what if there were small, 24-hour convenience-level grocery stores that could fill the glaring need for access to basics across the country?

Sweden has lost a few thousand smaller grocery stores in the last 25 years or so, mostly in rural areas. For many people living outside the cities, the nearest place to buy milk is several miles away, at a huge supermarket that’s either in a city, or close to it. After [Robert] built Sweden’s first 24-hour unmanned convenience store, the idea received quite a bit of media attention.

Five years and a pandemic later, the concept is still going strong. A chain of 30 of these bite-sized bodegas have popped up all over Sweden, run by a company called Lifvs. They have no staff at all, not even a cashier. Instead, shoppers unlock the door with their phones. They scan all their barcodes into an app, which provides a bill every month and is linked to both their bank account and national identity system. Beyond that, security is in the form of a single camera.

Because these tiny stores are staff-less, the prices can be kept relatively low. The only problem is that the technology is a bit of an issue for some older residents. Back in 2016, [Robert Ilijason] was trying to figure out another way for customers to unlock the door, but it doesn’t look like Lifvs has solved that problem yet.

One thing you can’t complain about with a store like this is the selection. We have to wonder if shoppers are more or less likely to encounter fasciated fruit amongst the produce.

Spherical Keyboard Build Leaves Hacker Well-Rounded

May 20, 2021 by Kristina Panos 20 Comments

Often times we as hackers don’t know what we’re doing, and we sally forth and do it anyway. Here at Hackaday, we think that’s one of the best ways to go about a new project, and the absolute fastest way to learn a whole lot as you go. Just ask [Aaron Rasmussen] regarding this spherical, standing 5×6 dactyl manuform keyboard build, which you can see in a three-part short video series embedded after the break.

[Aaron] gets right down to it in the first video. He had to get creative right away, slicing up the dactyl manuform model to fit on a tiny print bed. However, there’s plenty of room inside the sphere for all that wiring and a pair of Elite-C microcontrollers running QMK. Be sure to turn on the sound to hear the accompanying voice-overs.

The second video answers our burning question: how exactly does one angle grind a slippery sphere without sacrificing sheen or shine? We love the solution, which involves swaddling the thing in duct tape and foam.

You may be wondering how [Aaron] is gonna use any kind of mouse while standing there at the pedestal keyboard. While there is space for a mouse to balance on top, this question is answered in the third video, where [Aaron] learns the truth behind the iconic ThinkPad nubbin and applies this knowledge to build a force-feedback joystick/trackpoint mouse. Awesome answer, [Aaron]!

Not ready to go full-tilt, sci-fi prop ergo? Dip your toe in the DIY waters with a handy macropad.

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