It is a classic rite of passage for nerdy kids to write secret messages using lemon juice. If you somehow missed that, you can’t see the writing until you heat the paper up with, say, an old-fashioned light bulb. If you were a true budding spy, you’d write a boring normal letter with wide spacing and then fill in the blanks between the lines with your important secrets written in juice. This is a form of steganography — encoding secret messages by hiding them in plain sight. [Randomona] shares a different technique that seems to be way cooler than lemon juice using, of all things, turmeric. This isn’t like the invisible ink of our childhood.
That’s probably a good thing. We doubt an LED bulb makes enough heat to develop our old secret messages. [Ranomona’s] ink doesn’t use heat, but it uses a developer. That means you must make two preparations: the ink and the developer. The results are amazing, though, as shown in the video below.
We see a lot of clocks, and many of the better ones have some 3D printed elements to them. But [Carl Sabanski] shows us his kits for making sundials for either hemisphere using a conventional printer (you know, one that puts ink on paper), some styrofoam, and possibly some other materials like wire coat hangers, threaded rods, thumbtacks, glue, and different papers like transparencies or card stock.
In all, there are 21 different kinds of sundials. Some are pretty standard-looking fare, but there are others, like the pinwheel equatorial sundial or the cycloid polar sundial, which might be surprising. One even uses a CD as a kind of indicator.
This article was meant to be finished up before Christmas, so it’ll be a little late whenever you’re reading it to go and prepare this for the holiday. Regardless, if, like me, should you ever be on the lookout for something to give a toddler nephew or relative, it could be worth it to look into your neglected old parts shelves. In my case, what caught my eye was a 9-year-old AMD laptop catching dust that could be better repurposed in the tiny hands of a kid eager to play video games.
The main issues here are finding a decent selection of appropriate games and streamling the whole experience so that it’s easy to use for a not-yet-hacker, all the while keeping the system secure and child-friendly. And doing it all on a budget.
This is a tall order, and requirements will be as individual as children are, of course, but I hope that my experience and considerations will help guide you if you’re in a similar boat.
All across the country, parents are wondering what to do about the upcoming Trick Or Treat season. Measures such as social distancing, contact free treats, or simply doing it at home are all being weighed as a balance of fun and safety. [BuildXYZ] has decided to lean into the challenges this year and incorporate a mask as part of the costume for his boys.
It started with a 3d printed mask, printed in two halves, and sealed with silicon caulk and N95 filter material in the inlet and outlet holes on the sides. The real magic of the mask is the small OLED screen mounted to the front that works along with a small electret microphone inside the mask. By sampling the microphone and applying a rolling average, the Arduino Nano determines if the mouth drawn on the display should be open or closed. A small battery pack on a belt clip (with a button to flash “Trick or Treat” on the screen) powers the whole setup and can be easily hidden under a cape or costume.
This isn’t the first hack we’ve seen for Halloween this year, such as this socially distant candy slide. We have a feeling that there will be many more as the month rolls on and people start to apply their ingenuity to the season.
In several decades of hanging around people who make things, one meets a lot of people fascinated by locks, lock picking, and locksport. It’s interesting to be sure, but it had never gripped me until an evening in MK Makerspace when a fellow member had brought in his lockpicking box with its selection of locks, padlocks, and tools. I was shown the basics of opening cheap — read easy from that— padlocks, and though I wasn’t hooked for life I found it to be a fascinating experience. Discussing it the next day a friend remarked that it was an essential skill they’d taught their 12-year-old, which left me wondering, just what skills would you give to a 12-year-old? Continue reading “Ask Hackaday: What Skills Would You Give A Twelve Year Old?”→
We often hear it said that today’s kids don’t go out and play as much as they did in the past, but honestly, it’s hard to really blame them. Have you seen some of the games they have now? It’s going to take something a little more exciting than a game of stickball to get them off the couch when they’ve got 4K and VR game systems to play with.
Which is exactly why [Bobek] is building his kids a time machine. Not a literal one, of course. The Flux Capacitor technology required has yet to be mastered. But it does allow the player to “travel” through time through videos which are played by punching in specific codes they have to unlock by solving puzzles in the real world. Then again, keeping keeping kids active and mentally engaged might as well be “going back in time” in some people’s eyes.
By the looks of things, [Bobek] still has a little work to do on the project, but it’s far enough along that we can get an idea. Inside the bottom of the heavy duty plastic case he’s installed an ATX power supply and a Raspberry Pi 3, and an top of that, there’s a metal plate that holds the power button, an RGB backlit keyboard, and a Vacuum Florescent Display.
After powering on the system, the kids punch in the codes they’ve earned on the keyboard. If accepted, it starts the corresponding presentation which goes over the sights and sounds of the time period they’ve unlocked. In the video after the break you can see [Bobek] test the device with a small display hanging off the end of an HDMI cable, but presumably the system will eventually get an integrated display. The kids could also plug it into the TV, but at that point you might be going full circle.
I was a little surprised to see a news report about Andreas Schleicher, the director of education and skills at OECD — the Organization for Economic Cooperation and Development. Speaking at the World Innovation Summit for Education in Paris, Schleicher thinks that teaching kids to code is a waste of time. In particular, he seems to think that by the time a child today grows up, coding will be obsolete.
I can’t help but think that he might be a little confused. Coding isn’t going away anytime soon. It could, of course, become an even deeper specialty, and thus less generally applicable. But the comments he’s made seem to imply that soon we will just tell smart computers what we want and they will just do that. Somewhat like computers work on Star Trek.
What is more likely is that most people will be able to find specific applications that can do what they want without traditional coding. But someone still has to write something for the foreseeable future. What’s more, if you’ve ever tried to tease requirements out of an end user, you know that you can’t just blurt out anything you want to a computer and expect it to make sense. It isn’t the computer’s fault. People — especially untrained people — don’t always make sense or communicate unambiguously.