When we first heard of [Ildar Rakhmatulin’s] plan to use OpenCV on a Raspberry Pi to detect mosquitos and then zap them with a 1 watt laser, we thought it was sort of humorous. However, the paper points out that 700,000 people die each year from mosquito bites — we didn’t verify that, but according to the article that’s twice the number of people murdered each year. So the little pests are pretty effective assassins.
It looks as though the machine has been built, at least in a test configuration. A galvanometer aims the death ray using mirrors, and with the low power and lossy mirrors the mosquitos can only be a small distance from the machine — about a foot.
It does sound a bit silly — the idea that given enough time, a plant could influence the order of hardware-generated random numbers in order to get enough light to survive. But not so silly that [DeckerM] couldn’t wait to try it out after seeing a short clip about an unpublished study done at Princeton’s Engineering Anomalies Research (PEAR) lab that came to this very conclusion. The actual verbatim conclusion from the clip: “It’s as though life itself – even life or consciousness in something as simple as a house plant, bends probability in the physical world in the direction of what it needs, in the direction of its growth and evolution.”
The idea is this: a plant is made to suffer by languishing in the corner of a windowless room. The room has exactly one light in the middle of the ceiling — a repositionable spotlight of sorts that can only shine into any of the four corners and is controlled by a random number generator. A set of dividers ensure that none of the light leaks out of the quadrant and into any of the others.
[DeckerM]’s recreation of this experiment is much more practical. It’s essentially a little plywood cabinet with four open partitions and a ceiling. Each quadrant has a grow light strip planted in the corner, and all the wires are run through the top, where each has been stripped of its pesky power-governing controller and rewired to go straight into a smart plug. [DeckerM] is using a hardware RNG hosted on a Raspberry Pi, which is running a Python script that takes numbers from the RNG that corresponds to one of the quadrants, and then lights that quadrant.
And the results? They don’t really support the PEAR study’s bold conclusion unless viewed in small sample sizes, but [DeckerM] isn’t giving up that easily. Since the paper is unpublished, there are a lot of unanswered questions and juicy variables to play with, like the type, number, and age of the plants used. We’re excited to see if [DeckerM] can shed some light on plant psychokinesis.
Reddit user [duzitbetter] showed off their design for a 3D-printed programmable macro keyboard that offers a different take on what can be thought of as a sort of 3D-printed PCB. The design is called the Bloko 9 and uses the Raspberry Pi PICO and some Cherry MX-style switches, which are popular in DIY keyboards.
The enclosure and keycaps are all 3D printed, and what’s interesting is the way that the enclosure both holds the components in place as well as providing a kind of wire guide for all the electrical connections. The result is such that bare copper wire can be routed and soldered between leads in a layout that closely resembles the way a PCB would be routed. The pictures say it all, so take a look.
[NotLikeALeafOnTheWind] has created many LED-based display projects, and shares his method for making attractive LED panel frames and mounts. At first glance it may look as though slapping a rectangle of aluminum extrusion around a display is all it takes, there is also the mounting and management of wiring, power supply, and possibly a Raspberry Pi to deal with. The process of building an attractive frame also has a few hidden gotchas that can be avoided with a bit of careful planning.
Magnetic feet on the LED panels makes mounting much easier and more flexible.
Here is one tip that will resonate with some readers: don’t rely on specified dimensions of parts; measure the actual parts yourself. There can be small differences between what a data sheet says to expect, and the dimensions of the actual part in one’s hands. It may not be much, but it can be the difference between an ideal fit, and something that looks like a bit of a hack job.
[NotLikeALeafOnTheWind] provides some basic frame layouts, and suggests using two- or three-channel extrusions to provide a flat bezel around the display edge if desired. Mounting the LED panel itself is done with magnetic feet and providing a length of steel bar to which the display can attach. This can provide a flush mount while avoiding the whole issue of screw-mounting the display panels themselves, or sliding them into channels. For mounting all the other hardware, a piece of DIN rail and some 3D-printed parts takes care of that.
The result looks slick and sturdy, and some of the tips are sure to be useful even if the whole process isn’t applied. We like the way the basic design scales and is flexible about the thickness and size of the LED panels themselves, making it a promising way to accommodate perfectly functional oddball panels that end up in the trash.
Whether it’s for work, school, fun, or profit, nearly everyone is a content-creating video producer these days. And while OBS has made it easier to run the show, commanding OBS itself takes some hotkey finesse. Fortunately, it just keeps getting easier to build macro keyboards that make presenting a breeze. That includes the newest player to the microcontroller game — the Raspberry Pi Pico, which [pete_codes] used to whip up a nice looking OBS stream deck.
Sometimes you just need something that works without a lot of fuss — you can always save the fuss for version two. [pete_codes]’ Pico Producer takes advantage of all those I/O pins on the Pico and doesn’t use a matrix, though that is subject to change in the future. [pete_codes] likes the simplicity of this design and we do, too. You can see it in action after the break.
In reply to the Twitter thread, someone mentions re-legendable keycaps instead of the current 3D-printed-with-stickers keycaps, but laments the lack of them online. All we can offer is that re-legendable Cherry MX-compatible keycaps are definitely out there. Maybe not in white, but they’re out there.
It’s not every day we see a grand piano with a Raspberry Pi inside, let alone one with 96 motors, but sometimes we get lucky. The contraption in question is one developed by [Konstantin Leonenko], as part of a collaboration with composer [Patricia Alessandrini] for a piece she created inspired by Ada Lovelace. Specifically, [Patricia] was inspired by Ada’s idea that an “analytical machine” would, someday, be able to create music on its own. [Konstantin] and [Patricia] worked together to make a machine that would learn from it’s human co-performers and create music with them.
Their creation, rather than just one tricked-out keyboard, is actually a portable attachment that can be easily fitted to any grand piano. Each of the device’s 96 motors drives a plastic “finger” that excites the piano’s strings. The result is a sound unlike any other — and you really need to experience it so click through that link at the top for the demo video.
Rather cleverly, the fingers are designed such that their dynamics help to mask the sound of the motor (a must for performances) while simultaneously enhancing the string’s timbre. Like any project, this one went through a number of iterations over the two-year design process, and even spun off into an entirely new, glove-based version.
We’ve seen some awesome music tech hacks, and this one fits right in with the rest. It’s always exciting to see an instrument as ubiquitous as the piano be used in new and refreshing ways. Be sure to check out the link at the top for a video of this incredible instrument in action!
If you’ve ever pushed the needle a bit on your Raspberry Pi, there’s a good chance you’ve been visited by the dreaded lightning bolt icon. When it pops up on the corner of the screen, it’s a warning that the input voltage is dipping into the danger zone. If you see this symbol often, the usual recommendation is to get a higher capacity power supply. But experienced Pi wranglers will know that the board can still be skittish.
Sick of seeing this icon during his MAME sessions, [Majenko] decided to attack the problem directly by taking a close look at the power supply circuitry of the Pi 4. While the official schematics for everyone’s favorite single-board computer are unfortunately incomplete, he was still able to identify a few components that struck him as a bit odd. While we wouldn’t necessarily recommend you rush out and make these same modifications to your own board, the early results are certainly promising.
The first potential culprit [Majenko] found was a 10 ohm resistor on the 5 V line. He figured this part alone would have a greater impact on the system voltage than a dodgy USB cable would. The components aren’t labeled on the Pi’s PCB, but with a little poking of the multimeter he was able to track down the 0402 component and replace it with a tiny piece of wire. He powered up the Pi and ran a few games to test the fix, and while he definitely got fewer low-voltage warnings, there was still the occasional brownout.
Do we really need this part?
Going back to the schematic, he noticed there was a 10 uF capacitor on the same line as the resistor. What if he bumped that up a bit? The USB specifications say that’s the maximum capacitive load for a downstream device, but he reasoned that’s really only a problem for people trying to power the Pi from their computer’s USB port.
Tacking a 470 uF electrolytic capacitor to the existing SMD part might look a little funny, but after the installation, [Majenko] reports there hasn’t been a single low-voltage warning. He wonders if the addition of the larger capacitor might make removing the resistor unnecessary, but since he doesn’t want to mess with a good thing, that determination will be left as an exercise for the reader.
