How would you survive in a war-torn country, where bombs could potentially fall from the sky with only very short notice? And what if the bomb in question were The Bomb — a nuclear weapon? This concern is thankfully distant for most of us, but it wasn’t always so. Only 75 years ago, bombs were raining down on England, and until much more recently the threat of global thermonuclear war was encouraging school kids to “duck and cover”. How do you protect people in these situations?
The answers, naturally, depend on the conditions at hand. In Britain before the war, money was scarce and many houses didn’t have basements or yards that were large enough to build a family-sized bomb shelter in, and they had to improvise. In Cold War America, building bomb shelters ended up as a boon for the swimming pool construction industry. In both cases, bomb shelters proved to be a test of engineering ingenuity and DIY gumption, attempting to save lives in the face of difficult-to-quantify danger from above.
Elliot Williams and Mike Szczys dig through the most interesting hacks from the past week. On this episode we take a look at a portable power bank build that defies belief. We discuss an all-in-one SDR portable, messing with restaurant pagers, and the software that’s common to both of these pursuits. There’s a hopping robot that is one heck of a PID challenge, and another robot that does nothing but stare you down. We bring it on home with great articles on pianos with floppy disks, and that satellite cluster you should be watching for in the night sky.
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Visitors to the Wizarding World of Harry Potter at Universal Studios are able to cast “spells” by waving special interactive wands in the air. Hackers like us understand that there must be some unknown machinations happening behind the scenes to detect how the wands are moving, but for the kids wielding them, it might as well be real magic. So when his son asked to have a Harry Potter themed birthday party, [Adam Thole] decided to try recreating the system used at Universal Studios in his own home.
Components used in the IR streaming camera
The basic idea is that each wand has a reflector in the tip, which coupled with strong IR illumination makes them glow on camera. This allows for easy gesture recognition using computer vision techniques, all without any active components in the wand itself.
[Adam] notes that you can actually buy the official interactive wands from the Universal Studios online store, and they’d even work with his system, but at $50 USD each they were too expensive to distribute to the guests at the birthday party. His solution was to simply 3D print the wands and put a bit of white prismatic reflective tape on the ends.
With the wands out of the way, he turned his attention to the IR imaging side of the system. His final design is a very impressive 3D printed unit which includes four IR illuminators, a Raspberry Pi Zero with the NoIR camera module. [Adam] notes that his software setup specifically locks the camera at 41 FPS, as that triggers it to use a reduced field of view by essentially “zooming in” on the image. If you don’t request a FPS higher than 40, the camera will deliver a wider image which didn’t have any advantage in this particular project.
The last part of the project was taking the video stream from his IR camera and processing it to detect the bright glow of a wand’s tip. For each frame of the video the background is first removed and then any remaining pixel that doesn’t exceed a set brightness level if ignored. The end result is an isolated point of light representing the tip of the wand, which can be fed into Open CV’s optical flow function to show [Adam] what shape the user was trying to make. From there, his software just needs to match the shape with one of the stock “spells”, and execute the appropriate function (such as changing the color of the lights in the room) with Home Assistant.
Overall, it’s an exceptionally well designed system considering the goal was simply to entertain a group of children for a few hours. We almost feel bad for the other parents in the neighborhood; it’s going to take more than a piñata to impress these kids after [Adam] had them conjuring the Dark Arts at his son’s party.
Shenzhen, China is the home of the legendary electronics markets of Huaqiangbei. Friday was my first full day in the city, having spent the previous three days in Shanghai. We got a little bit of a late start as our flight didn’t arrive until after 1 am and we stayed at the first night at an airport hotel. We met up with Scotty Allen for an amazing meal followed by a very unique experience in the electronics markets, not just seeing the items, but meeting the booth owners who showed off some of their secrets.
The day was capped off by an absolutely packed meetup at X.factory, the collaborative creative space run by Seeed Studio. They lined up a half dozen hardware talks that were quite excellent, and there was a ton of hardware being demonstrated as the night progressed. They had to kick us out or we’d have stayed all night!
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.
Think of bicycles, and your first mental image could be something pretty fancy. Depending on which side of the sport you favor, you could end up thinking of a road bike or an MTB, maybe DH, CX, BMX, TT, tandem or recumbent.
But for people in most parts of the World such as Asia, Africa and South America, the bicycle conjures up a very different image – that of the humble roadster. And this simple, hardy machine has spawned innumerable hacks to extend its usefulness and functionality by enterprising people with limited means. For them, it is not as much a means of transport, as a means for livelihood and survival. Continue reading “Hacking The Humble Roadster Bicycle”→
The world is full of educational robots for STEAM education, but we haven’t seen one as small or as cute as the Skoobot, an entry in this year’s Hackaday Prize. It’s barely bigger than an inch cubed, but it’s still packed with motors, a battery, sensors, and a microcontroller powerful enough to become a pocket-sized sumo robot.
The hardware inside each Skoobot is small, but powerful. The main microcontroller is a Nordic nRF52832, giving this robot an ARM Cortex-M4F brain and Bluetooth. The sensors include a VL6180X time of flight sensor that has a range of about 100mm. Skoobot also includes a light sensor for all your robotic photovoring needs. Other than that, the Skoobot is just about what you would expect, with a serial port, a buzzer, and some tiny wheels mounted in a plastic frame.
The idea behind the Skoobot is to bring robotics to the classroom, introducing kids to fighting/sumo robots, while still being small, cheap, and cute. To that end, the Skoobot is completely controllable via Bluetooth so anyone with a phone, a Pi, or any other hardware can make this robot move, turn, chase after light, or sync multiple Skoobots together for a choreographed dance.
