It has recently been possible to pay a service a little bit of money and learn more about your own DNA. You might find out you really aren’t Italian after all or that you are more or less susceptible to some ailments. [Paul Klinger] had his DNA mapped and decided to make a sculpture representing his unique genetic code. The pictures are good, but the video below is even better.
The project requires a DNA sequencing, a 3D printer, and a Raspberry Pi Zero. Oh, you can probably guess you need a lot of RGB LEDs, too. Of course, the display doesn’t show the whole thing at one time — your DNA pattern scrolls across the double helix.
The Pomodoro Technique has helped countless people ramp up their productivity since it was devised in the late 1980s. Breaking down tasks into 25 minute chunks can improve your focus tremendously, provided you show up, start the timer, and get to work.
Lazydoro takes the psychology focus even further. In [romilly.cocking]’s interpretation, a time-of-flight (ToF) sensor is your productivity Santa Claus — it knows whether you’re doing your part by simply applying butt to chair, and your present is a productive 25 minutes where not a second is wasted futzing with timers and worrying about time lost to such administrative tasks. When Lazydoro senses that you have arrived, the Raspi Zero starts a 25-minute Pomodoro timer, and represents the time remaining across a Pimoroni BLINKT LED matrix.
But hold on, you haven’t heard the best part yet. Lazydoro was designed with real life in mind, because [romilly] thought of everything. Whenever you leave your chair, a 5-minute timer starts, and there’s a beep when time is up. If you make it through the 25 minutes and hear the victory beep, then it’s break time. But if you get up too soon, the work timer stops, and the 5-minute timer becomes your limited space in which to fret, stare out the window, or get the snack you think you desperately need to keep going. This makes Lazydoro awesome even without the Pomodoro part, because simply sitting back down is a big step one.
If you make a circuit sculpture Pomodoro and stare at it on your 5-minute breaks, you might achieve productivity enlightenment.
Never underestimate the quick and dirty hack. It’s very satisfying to rapidly solve a real problem with whatever you have on hand, and helps to keep your hacking skills sharp for those big beautifully engineered projects. [Guillaume M] needed a way to remotely open his apartment building door for deliveries, so he hacked the ancient intercom to be operated via Telegram, to allow packages to be deposited safely inside his mailbox inside the building’s front too.
[Guillaume] needed to complete the hack in a way that would allow him to return the intercom to its original state when he moves out. Opening the 30-year-old unit, he probed a row of screw terminals and identified a 13V supply, ground, and the connection to the buildings’ door lock. He connected the lock terminals to a relay, which is controlled by a Raspberry Pi Zero W that waits for the “open” command to be sent to a custom Telegram Bot.
To power the Pi, [Guillaume] connected it to the 13V supply on the intercom via a voltage divider circuit. Voltage dividers usually make lousy power supplies, since the output voltage will fluctuate as the load changes, but it looks as though it worked well enough for [Guillaume]. The intercom had a lot of empty space inside, so after testing everything was packed inside the housing.
Linux! Such a wonderful, rich, capable operating system has blessed us, and all for the low, low cost of absolutely free. It’s under the hood of countless servers, computers, phones, and embedded devices, and is the go-to solution for when you want to get the job done right. Why, then, does it curse me so?
Prologue
The penguin giveth, and the penguin taketh away.
My experience with the almighty penguin stretches back to the late 90s. Facebook hadn’t been invented yet, so most weekends were spent installing whatever came on the front of the latest computer mags. I wish I was kidding, but I’m really not.
Way back when, us kids would load the latest Red Hat or Fedora distribution onto our hand-me-down Pentium IIs, trying not to accidentally wipe our hard drive in the process. Limited to dial-up internet and very few help resources, it was pretty common that you’d spend hours watching progress bars tick over, only to wind up with no working mouse, or an X server that simply refused to start for man or God. Did I mention we did all this for fun?
Trying To Get Some Work Done
Of course, after growing up, real life and real responsibilities take over. Now, if I’m using Linux, it’s because I’ve got a job to do, not just because there’s nothing good to watch on Cartoon Network this weekend. I consider myself to be a fairly intermediate user. I’ve compiled a few things successfully, understood how to work with a variety of package managers, and once, just once, even managed to connect to a wireless network from the command line. There’s not a whole lot that phases me in this realm anymore.
For the past few years, I’ve been slowly working on a little rover by the name of TKIRV, powered by a Raspberry Pi. It was overdue for a camera upgrade, as I’d been using an old Microsoft webcam for far too long. I ordered a nice 1080p Raspberry Pi camera, and naturally the parts marinated in their boxes for a good couple of years. Finally, after much procrastination, I was eager to get my wheely boi back out on the road.
This was but the beginning my weekend slaying embedded Linux dragons.
Despite all the progress video game graphics have made, it is safe to say that we won’t see any decline in oldschool 8-bit games any time soon. For some it’s about nostalgia, for others it’s just a great and simple-enough first step into game development itself. For [gocivici] it was a bit of both when he built this camcorder style, one-button gaming console.
With a Raspberry Pi Zero running PICO-8 at its core, [gocivici] salvaged the viewfinder of an old camcorder for the display, and that way turned it into a whole other kind of handheld console. For full ergonomic handling, one single, thumb-operated push button serves as only control option. This of course makes it a bit challenging to re-use existing games that would require more input options, so he and some friends decided to just write a suitable game on their own with the hopes that others might follow.
Unfortunately we don’t see a lot of projects using these old camcorder viewfinders, and considering modern LCD and OLED options it’s not really that surprising, but there’s just something intriguing about these tiny CRTs. So in case you want to see more of them, have a look at this tiny Atari display, and the DIY night vision monocle from a few years back. And to keep your eyes safe and sound, [gocivici] got you covered as well.
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.
Since the Pi Zero was released, there have been many attempts to add a power bank. Cell phone batteries are about the same size as a Pi Zero, after all, and adding a USB charging port and soldering a few wires to a Pi is easy. The PiSugar is perhaps the cutest battery pack we’ve seen for the Pi Zero, and it comes in a variety of Hats compatible with the Pi, capable of becoming a small display, a keyboard, or any other thing where a small, portable Linux machine is useful.
The core of this build is a small circuit board the size of a Pi Zero. Attached to this board is a 900mAh battery, and the entire assembly is attached to the Pi Zero with a set of two spring clips that match up with with a pair of pads on the back of the Pi. Screw both of these boards together, and you have a perfect, cableless solution to adding power to a Pi Zero.
But the PiSugar doesn’t stop there. There are also cases, for a 1.3 inch LCD top, a 2.13 inch ePaper display, an OLED display, a camera, a 4G module, and something that just presents the pins from the Pi GPIO header. This is an entire platform, and if you print these parts in white plastic, they look like tiny little sugar cubes filled to the brim with electronics and Linux goodness.
Yes, you’ve seen 3D printed Pi cases before, but nothing in the way of an entire platform that gives you a Pi Zero in an extensible platform that can fit in your pocket and looks like sweet, sweet cubes of sucrose.