This excellent content from the Hackaday writing crew highlights recurring topics and popular series like Linux-Fu, 3D-Printering, Hackaday Links, This Week in Security, Inputs of Interest, Profiles in Science, Retrotechtacular, Ask Hackaday, Teardowns, Reviews, and many more.
This week, Jonathan Bennett talks Session and cryptocurrency skepticism with Kee Jefferys! Why fork Signal? How does Session manage to decentralize? And why the cryptocurrency angle? Listen to find out!
Continue reading “FLOSS Weekly Episode 819: Session, It’s All Abot The Metadata”
What has puzzled researchers and philosophers for many centuries is the ‘why’ of sleep, along with the ‘how’. We human animals know from experience that we need to sleep, and that the longer we go without it, the worse we feel. Chronic sleep-deprivation is known to be even fatal. Yet exactly why do we need sleep? To rest our bodies, and our brains? To sort through a day’s worth of memories? To cleanse our brain of waste products that collect as neurons and supporting cells busily do their thing?
Within the kingdom of Animalia one constant is that its brain-enabled species need to give these brains a regular break and have a good sleep. Although what ‘sleep’ entails here can differ significantly between species, generally it means a period of physical inactivity where the animal’s brain patterns change significantly with slower brainwaves. The occurrence of so-called rapid eye movement (REM) phases is also common, with dreaming quite possibly also being a feature among many animals, though obviously hard to ascertain.
Most recently strong evidence has arisen for sleep being essential to remove waste products, in the form of so-called glymphatic clearance. This is akin to lymphatic waste removal in other tissues, while our brains curiously enough lack a lymphatic system. So is sleeping just to a way to scrub our brains clean of waste?
Continue reading “Investigating Why Animals Sleep: From Memory Sorting To Waste Disposal”
If you watch the New Year’s festivities from New York, you know that they mark midnight with the dropping of a big, gaudy ball. You might assume this was just an arbitrary gimmick, but it turns out dropping balls has a place in the history of timekeeping, especially for ships at sea. The New York ball doesn’t work precisely the same, but it was clearly inspired by an ancient method of indicating the time.
Apparently, even the ancient Greeks used ball dropping to indicate time. But the modern ball got its start with [Captain Robert Wauchope], who installed one at Portsmouth, England, in 1829. The Royal Observatory in Greenwich got one in 1833, which you can see working in the video below.
Have you ever wished you could experiment with different layouts super easily, just by adding or removing a few switches here and there and printing a new case? Well, [heyisjambo] says that it’s more than possible with menura, the modular keyboard system.
At the same time, [heyisjambo] wanted to experiment with split vs. uni-body construction, and especially the different shapes that are possible when tweaking the angle and distance between them.
And as if that weren’t enough, there’s support for [Sadek Baroudi]’s VIK standard for interfacing data between PCBs, which calls for an FPC 12-pin, 0.5 mm pitch connector and allows for ultra-cool magnetic connectors. This way, you can easily add things like displays, trackpads, and trackballs in the between the halves.
Thanks for the tip, [calculus]!
Continue reading “Keebin’ With Kristina: The One With The Keyboard Configurator”
Join us on Wednesday, February 5 at noon Pacific for the Underwater Robotics Hack Chat with Tony White!
Almost anywhere you look, there’s a good chance you can see a robot at work. Whether they’re sweeping your floors, delivering a snack, building a car, or even driving one, robots are everywhere on this planet. And since over 70% of this planet is covered in water, it makes sense that robots should be there, too. Getting a robot to work underwater at all is one thing, but getting it to work underwater reliably can be quite a challenge. Water always finds a way to ruin your day, after all, and this reality only worsens when you add a little salt into the mix.
Tony White knows the marine engineering field well, having worked in the space for over a decade. He’s currently an applications engineer at Blue Robotics, where he’s worked on everything from full-size autonomous surface vessels to underwater swarm robots. He’s stopping by the Hack Chat to talk about the harsh engineering realities of underwater automation, so if you’ve ever wanted to take the plunge, you’ll want to come to this Hack Chat for sure.
Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 5 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.
All things considered, it was a very bad week for aviation here in the United States. Three separate crashes, two of which involved US military aircraft, have left over 70 people dead. We’ll spare you the details since there are plenty of other places to get news like that, but we did want to touch on one bright spot in this week’s aviation news: the first successful supersonic flight by a US-made civilian aircraft. There are a lot of caveats to that claim, but it’s clear that Boom Supersonic is on a path to commercializing supersonic air transportation for the first time since the Concorde was retired. Their XB-1 “Baby Boom” test aircraft managed three separate supersonic runs during the January 28 test flight over the Mojave test range. As usual, Scott Manley has excellent coverage of the test flight, including a look at how Boom used a Starlink terminal and an iPhone to stream cockpit video.
A few months ago, Hackaday’s own Al Williams convinced me to buy a couple of untested, returned-to-manufacturer 3D printers. Or rather, he convinced me to buy one, and the incredible success of the first printer spurred me on to the second. TL;DR: Lightning didn’t strike twice, but I’d still rate it as worth my time. This probably isn’t a good choice for your first printer, but if you’ve done the regular maintenance on your first printer already, I’d recommend it for your second or twelfth.
As background, Al has been volunteering with local schools to teach a 3D printing summer class, and this means outfitting them with a 3DP lab on the dirt cheap. His secret is to buy last year’s model which has all of the features he needs – most importantly for the kids, automatic bed height probing – but to buy it from the scratch-and-dent shelf at Creality. Why? Because they are mid-grade printers, relatively new, but on deep discount.
How deep? I found an essentially endless supply of printers that retail for $300 on discount for $90 each. The catch? It might work, it might not. I bought my son one, because I thought that it would at least make a good project for us to work on together. Those plans were spoiled – it worked absolutely flawlessly from the moment we bolted it together, and he runs 24-hour jobs on the thing without fear. From the look of the build plate, it had been used exactly once and returned for whatever reason. Maybe the owner just didn’t want a 3D printer?
The siren song of straightforward success was too much for me to resist, and I picked another up to replace my aging A8 which was basically a kit for a 3D printer, and not a particularly good one at that, but could be made to work. My scratch-and-dent Creality came with a defective bed-touch sensor, which manifest itself as a random absolute refusal to print.
I took it apart, but the flaw is in the design of the V1 touch sensors – the solenoid requires more current to push down than the 3DP motherboard can reliably deliver. It works 100% of the time on my bench power supply, but in situ it fails about 30% of the time, even after hitting it with graphite and making sure everything is mechanically sound. Creality knows this and offers a free trade-in, just not for me. The new version of the Creality probe costs $50 new, but you can get cheap knock-off BL Touch models for $14. Guess what I did?
And guess what bit me? The cheapo touch probe descends a bit slower than the Creality version should, and the firmware is coded to time-out in an extra-short timeframe. Thankfully, Creality’s modifications to Marlin are all open source, and I managed to tweak and flash a new firmware that made it work 100% of the time, but this was at a cost of probably eight hours of bug-hunting, part-ordering, and firmware-compiling. That said, I got some nice extra features along the way, which is the advantage of a printer running open-source firmware.
So my $300 printer cost me $105, plus eight hours of labor. I only charge one coffee per hour for fun hardware debugging tasks, but you may have a different valuation. Taken together with my son’s printer, we have $600 worth of printer for under $200 plus labor, though, which starts to sound a little better.
Is gambling on an untested return 3D printer worth it? For us, I would say it was, and I’d do it again in a few years. For now, though, we’ve got three printers running and that’s all we need. Have you gone down this perilous path?
