The latest craze in revolutionary materials science is no longer some carbon nanotube, a new mysterious alloy, or biodegradeable plastic. It seems as though a lot of new developments are coming out of the biology world, specifically from mycologists who study fungi. While the jury’s still out on whether or not it’s possible to use fungi to build a decent Star Trek series, researchers have in fact been able to use certain kinds of it to build high-performing insulation.
The insulation is made of the part of the fungus called the mycelium, rather than its more familiar-looking fruiting body. The mycelium is a strand-like structure of fungus which grows through materials in order to digest them. This could be mulch, fruit, logs, straw, crude oil, or even live insects, and you might have noticed it because it’s often white and fuzzy-looking. The particular type of mycelium used here is extremely resistant to changes in temperature so is ideal for making insulation. As a bonus, it can be grown, not manufactured, and can use biological waste products as a growing medium. Further, it can grow to fit the space it’s given, and it is much less environmentally harmful than existing forms of insulation.
Throughout human history, people try to make the biggest, the fastest, and — sometimes — the smallest. [Hellmood] falls into the latter category and proves it with a 64 byte interactive 3D raycasting application for MSDOS.
Why MSDOS? We suppose why not? The .COM file format is lean, and you can take over everything without a lot of work. If the program were huge, it wouldn’t be very impressive. There are 64 shades of gray which is odd looking these days, however there are versions that use various color palettes and each one fits in 64 bytes or less. There’s even mouse control and you can see the results in the video below.
You’d be forgiven for not realizing there’s still a diehard group of people out there carrying around dedicated MP3 players. While they were all the rage a decade or so back, most consumers have since moved over to using their handy dandy pocket supercomputer for playing their music. Plus controlling every other aspect of their personal life and finances, of course. Though that’s another story entirely.
But as [Conno Brooks] explained to us, there’s a sizable group of open source fanatics who prefer to store their jams on devices running the Rockbox firmware. Only problem is, some of the desirable Rockbox-compatible players are from the Golden Age of dedicated players, and aren’t getting any younger. In a recent blog post, he briefly goes over his ultimately successful attempt to put a new-made battery into his Sansa Clip+, a particularly desirable player that was released in 2009.
There are a few problems with the procedure that has kept it from being very widespread, according to [Conno]. For one, the Sansa Clip+ is tiny and not easily disassembled without destroying it. Worse, the diminutive 30mm x 36mm x 3mm OEM battery is effectively unobtainium. But ironically he was able to find an even smaller battery which seemed like it should work, assuming he could get it wired up.
The OEM battery on the Clip+ uses three wires, which [Conno] presumed was part of some thermal protection system. He first tried to take the circuit board off the original dead battery and graft it onto the modern cell, but something must have tripped because the resulting Franken-pack didn’t output any voltage. On his second attempt he simply ignored the third wire, and luckily the Clip+ didn’t seem to complain and started up as expected.
[Conno] says there’s some careful flexing required to get the new pack installed and the Clip+ closed properly, and the device’s runtime is somewhat diminished by the new battery’s lower capacity. But if it means another few years of keeping Big Brother out of your digital media habits, he figures it’s a worthy trade.
Ever since a Dutch businessman peered into the microscopic world through his brass and glass contraption in the 1600s, microscopy has had a long, rich history of DIY innovation. This DIY fluorescence microscope is another step along that DIY path that might just open up a powerful imaging technique to amateur scientists and biohackers.
In fluorescence microscopy, cells are treated with various fluorescent dyes that can be excited with light at one wavelength and emit light at another. But as [Jonathan Bumstead] points out, fluorescence microscopes are generally priced out of the range of biohackers. His homebrew scope levels the playing field a bit. The trick is to use 3D-printed parts to kit out commonly available digital cameras – a USB microscope, a DSLR, or even a smartphone camera. Excitation is provided by a ring of Nexopixel LEDs, while a movable rack holds a filter that blocks the excitation wavelength but allows the emission wavelength to pass through to the camera. He demonstrates the technique by staining some threads with fluorescent ink from a highlighter marker and placing them on a sheet of tissue paper; in conventional bright-field mode, the threads all but disappear into the background, but jump right out under fluorescence.
Ith’s true that the optics are not exactly lab quality, and the microscope is currently only set up to do reflectance imaging as opposed to the more typical transmissive mode where the light passes through the sample. That’s an easy fix, though, and reflectance mode is still useful. We’ve seen fluorescence microscopy get quite complex before, but this simple scope might be enough to get a biohacker started.
When Microsoft announced the Xbox adaptive controller earlier this year, many were pleasantly surprised at how adaptive it truly was. The controller features 3.5mm jacks for easily connecting any external input device and sports an impressive build quality given its price tag, but the most impressive part was the fact that the design was so open in nature. Rather than seeking to create a specific design solution tailored to a subset of users the adaptive controller acts more as a hub for the community’s designs. One of those brilliant designs comes from [Colton] who posted a five-part series on his custom controller build for his daughter.
His daughter, Ellie, has Cornelia de Lange syndrome which prevents her from being able to use more conventional pressure sensitive input devices. So [Colton] devised a way for buttons to be pressed using an alternate range of motion. By attaching foam massage inserts to standard paint rollers, the buttons could be triggered by allowing the peaks and valleys of the foam to roll over the top of each button. He could achieve even better accuracy by attaching braided ribbon over the buttons in order to prevent binding.
After finding that setup to be successful, [Colton] went about designing a frame. He arrived at using PVC pipe and utilizing tees as anchor points for the rollers. A couple of steel hose clamps are enough to hold each of the foam rollers in place, and the contact distance can be dialed in with buttons housed in threaded PVC adapters (shown right). After the addition of a little colored wrap here and there the build has a decidedly cheery exterior.
However, the build was not complete without a custom piece of software to match. [Colton] reached out for help from his nephew to program a “RGB Etch-a-Sketch” they called Sundoodler. The game runs on a small form factor PC hooked up to a projector so Ellie can play lying down. [Colton] has some future plans for his daughter’s custom Xbox adaptive controller build, but for now you can see the results in the video below.
We are all familiar with the idea of a hologram, either from the monochromatic laser holographic images you’ll find on your bank card or from fictional depictions such as Princes Leia’s distress message from Star Wars. And we’ve probably read about how the laser holograms work with a split beam of coherent light recombined to fall upon a photographic plate. They require no special glasses or headsets and possess both stereoscopic and spatial 3D rendering, in that you can view both the 3D Princess Leia and your bank’s logo or whatever is on your card as 3D objects from multiple angles. So we’re all familar with that holographic end product, but what we probably aren’t so familiar with is what they represent: the capture of a light field.
In his Hackaday Superconference talk, co-founder and CTO of holographic display startup Looking Glass Factory Alex Hornstein introduced us to the idea of the light field, and how its capture is key to the understanding of the mechanics of a hologram.
His first point is an important one, he expands the definition of a hologram from its conventional form as one of those monochromatic laser-interference photographic images into any technology that captures a light field. This is, he concedes, a contentious barrier to overcome. To do that he first has to explain what a light field is.
When we take a 2D photograph, we capture all the rays of light that are incident upon something that is a good approximation to a single point, the lens of the camera involved. The scene before us has of course countless other rays that are incident upon other points or that are reflected from surfaces invisible from the single point position of the 2D camera. It is this complex array of light rays which makes up the light field of the image, and capturing it in its entirety is key to manipulating the result. This is true no matter the technology used to bring it to the viewer. A light field capture can be used to generate variable focus 2D images after the fact as is the case with the Lytro cameras, or it can be used to generate a hologram in the way that he describes.
The point of his talk is that complex sorcery isn’t required to capture a light field, something he demonstrates in front of the audience with a volunteer and a standard webcam on a sliding rail. Multiple 2D images are taken at different points, which can be combined to form a light field. The fact that not every component of the light field has been captured doesn’t matter as much as that there is enough to create the holographic image from the point of view of the display. And since he happens to be head honcho at a holographic display company he can show us the result. Looking Glass Factory’s display panel uses a lenticular lens to combine the multiple images into a hologram, and is probably one of the most inexpensive ways to practically display this type of image.
Since the arrival of the Lytro cameras a year or two ago the concept of a light field is one that has been in the air, but has more often been surrounded by an air of proprietary marketing woo. This talk breaks through that to deliver a clear explanation of the subject, and is a fascinating watch. Alex leaves us with news of some of the first light field derived video content being put online and with some decidedly science-fiction possible futures for the technology. Even if you aren’t planning to work in this field, you will almost certainly encounter it over the next few years.
It feels like that Neo Geo Mini kinda came and went. All the hype surrounding the idea of having a tiny usable arcade machine melted away when the original system’s fans first touched the “non-clicky” joystick. While it was encouraging to see the inclusion USB-C power, there was no internal battery to allow players to use the system untethered. Not satisfied with the product in its current state [Ben Heck] shot a video detailing his latest portable creation using the Neo Geo Mini internals.
The design of the portable focuses around incorporating aspects of the Neo Geo MVS arcade system that the Neo Geo Mini lacks. The D-pad includes tiny micro-switches, or as [Ben Heck] calls them nano-switches, for a decidedly more tactile feel. He was able to re-purpose the speakers and headphone jack from the original PCB along with the 4:3 aspect ratio LCD. The custom faceplate wraps everything in the familiar red and white insignia while the 3D printed face buttons come in the classic red, yellow, green, and blue. Don’t worry, they are finally in the right button configuration here.
It’s great to see [Ben Heck] still making portable magic since his YouTube show ended earlier this year. He has contributed a lot to the modding community over the years, and there are plenty of helpful tips scattered throughout this Neo Geo Mini portable video as well. Note that the build is split into two separate videos (part two is below). We look forward to many more projects like this from [Ben Heck] in the future.