Month: July 2024

French acrobatic artist [Bastien Dausse] flies around on an impressive anti-gravity device he created.

Low-Gravity Playground Looks Highly Entertaining (and Useful)

July 28, 2024 by 22 Comments

With US astronauts scheduled to return to the Moon in 2026, it might be nice for them to really and truly know ahead of time what the gravity situation is going to be like. At 1/6th Earth’s gravity, the difference can be difficult to simulate.

But not anymore. French acrobatic artist [Bastien Dausse] has created a contraption that does exactly that. [Dausse] straps himself in, and is instantly able to slowly sproing about, up and down and all around in semi-slow motion, using this device which is calibrated to the Moon’s gravity. [Dausse]’s troupe’s performances center on the idea of gravity and of subverting it.

In order to achieve this effect, the swooping sculpture uses a pair of large counterweights. Check out the video below to see how they too become part of the action during a captivating duet performance. Although not attached, part of the device is a disk on which it smoothly moves around. It looks really fun, and more than a little bit dangerous. But mostly fun.

Did you know that Da Vinci created several experiments dedicated to determining the properties of gravity?

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AMD Returns To 1996 With Zen 5’s Two-Block Ahead Branch Predictor

July 28, 2024 by 14 Comments

An interesting finding in fields like computer science is that much of what is advertised as new and innovative was actually pilfered from old research papers submitted to ACM and others. Which is not to say that this is necessarily a bad thing, as many of such ideas were not practical at the time. Case in point the new branch predictor in AMD’s Zen 5 CPU architecture, whose two-block ahead design is based on an idea coined a few decades ago. The details are laid out by [George Cozma] and [Camacho] in a recent article, which follows on a recent interview that [George] did with AMD’s [Mike Clark].

The 1996 ACM paper by [André Seznec] and colleagues titled “Multiple-block ahead branch predictors” is a good start before diving into [George]’s article, as it will help to make sense of many of the details. The reason for improving the branch prediction in CPUs is fairly self-evident, as today’s heavily pipelined, superscalar CPUs rely heavily on branch prediction and speculative execution to get around the glacial speeds of system memory once past the CPU’s speediest caches. While predicting the next instruction block after a branch is commonly done already, this two-block ahead approach as suggested also predicts the next instruction block after the first predicted one.

Perhaps unsurprisingly, this multi-block ahead branch predictor by itself isn’t the hard part, but making it all fit in the hardware is. As described in the paper by [Seznec] et al., the relevant components are now dual-ported, allowing for three prediction windows. Theoretically this should result in a significant boost in IPC and could mean that more CPU manufacturers will be looking at adding such multi-block branch prediction to their designs. We will just have to see how Zen 5 works once released into the wild.

Print Your Own Magnetic Connector

July 27, 2024 by 22 Comments

If you have a late-model laptop, you’ve probably seen how the chargers magnetically snap into place. In theory, this should be easy to recreate for your own purposes. But why reinvent the wheel when [DarthKaker] has already done the work for you — assuming you only need two conductors.

The 3D-printed shells take the usual round magnets. Obviously, the north pole on one part should point to the south pole on the other part. In addition, if polarity matters, you should also have each housing contain one north-facing and one south-facing magnet so that the connectors will only mate one way.

It appears the project uses wires soldered or spot welded to the magnets. Heating magnets sometimes has bad effects, so we might try something different. For example, you could solder the wires to thin washers affixed to the magnets with epoxy, perhaps. Or use the magnets for alignment and make a different arrangement for the contacts, although that would take a different shell design.

We have talked about magnet soldering for connectors before. Don’t forget that you can build magnets into your prints, too.

The BAPPR Keeps Your Addressable LED System Cool

July 27, 2024 by 17 Comments

We all love a nice strip or grid of addressable LEDs. It can add flair or an artistic touch to many projects, and it can make gaming computers look extra 1337. However, providing enough current to a long strip of addressable LEDs can sometimes be difficult. Often a separate voltage rail is needed to supply enough juice. At the same time, continually sending out data to animate them can often use 100% of the microcontroller’s CPU power, especially if the serial bus is being bit-banged. A crash or badly timed interrupt can leave the system in a weird state and sometimes with the LEDs not displaying the correct colours. Or you might just want to enter a power-saving mode from time to time on your main MCU? Well, the BAPPR is designed to address all of these problems.

[TheMariday] created the BAPPR and made it fully open-source. It’s a switch-mode power supply that can accept anywhere from 7 V to 17 V and converts it into a strong 5 V rail for typical addressable LEDs. It also has a “smart” mode where it monitors the data line going to the LEDs to see if there is activity. If for some reason the system stops sending data, the BAPPR can intervene and shut off the power to the LEDs, which can help prevent strange colour combinations from being displayed while the system recovers. Once data starts flowing again, power is restored and the light party can resume.

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MIDI Controller In A Cubic Inch

July 27, 2024 by 2 Comments

MIDI as a standard has opened up a huge world to any musician willing to use a computer to generate or enhance their playing and recording. Since the 80s, it has it has revolutionized the way music is produced and performed, allowing for seamless integration of digital instruments, automation of complex sequences, and unprecedented control over everything from production to editing. It has also resulted in a number of musical instruments that probably wouldn’t be possible without electronic help, like this MIDI instrument which might be the world’s smallest.

Fitting into a cubic inch of space, the tiny instrument’s volume is mostly taken up by the MIDI connector itself which was perhaps an acceptable size by 1980s standards but seems rather bulky today. A two-layer PCB split into three sections sandwiches the connector in place and boasts an ATtiny85 microcontroller and all the associated electronics needed to implement MIDI. Small threaded screws hold the platform together and provide each layer with a common ground. Four small pushbuttons at the top of the device act as the instrument’s keys.

The project’s creator (and Hackaday alum!) [Jeremy Cook] has it set up to play notes from a piano right now, but has also made the source code available so that any musical action can be programmed onto these buttons. Flexibility is perhaps MIDI’s greatest strength and why the standard has lasted for decades now, as it makes it fairly straightforward to build more comprehensive, easy-to-learn musical instruments or even musical instruments out of retro video game systems.

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Need Many Thin Parts? Try Multi-material Stack Printing

July 27, 2024 by 9 Comments

Admittedly it’s a bit of a niche application, but if you need lots of flat 3D printed objects, one way to go about it is to print them in a stack and separate them somehow. An old(er) solution is to use a non-extruding “ironing” step between each layer, which makes them easier to pull apart. But another trick is to use the fact that PLA and PETG don’t stick well to each other to your advantage. And thus is born multi-material stack printing. (Video, embedded below the break.)

[Jonathan] wants to print out multiples of his fun Multiboard mounting system backplates, and these are the ideal candidate for stack printing: they’re thin, but otherwise take up the entire build plate. As you’d expect, the main trick is to print thin layers of PETG between the PLA plate layers that you do want. He demonstrates that you can then simply pull them apart.

There are some tricks, though. First is to make two pillars in addition to the plates, which apparently convinces the slicer to not flatten all the layers together. (We don’t really understand why, honestly, but we don’t use Bambu slicer for multi-materials.) The other trick that we expect to be more widely applicable, is that [Jonathan] extrudes the PETG interlayers a little thicker than normally. Because the PETG overflows the lower PLA layer, it physically locks on even though it chemically doesn’t. This probably requires some experimentation.

As multi-material printers get cheaper, we’ve seen a lot more innovative uses for them popping up. And we wouldn’t be so stoked about the topic if there weren’t a variety of hacker projects to make it possible. Most recently, the impressive system from [Armored_Turtle] has caught our eye. Who knows what kind of crazy applications we’ll see in the future? Are you doing multi-material yet?

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A History Of Internet Outages

July 27, 2024 by 30 Comments

We heard a story that after the recent hurricane, a man noted that while the house was sweltering hot because the power was still out, his kids were more anxious for the internet to come back online. The Internet is practically a basic necessity for most people, but as you may have noticed with the recent CrowdStrike debacle, the Internet isn’t always reliable. Granted, the problem in that case wasn’t the Internet per se, but a problem with many critical hosts that provide services. [Thomas Germain] from the BBC took the opportunity to recall some of the more bizarre reasons we’ve had massive Internet outages in the past.

While teens after a hurricane might miss social media, global outages can be serious business. With 8.5 million computers dead, 911 services went down, medical surgeries were canceled, and — of course — around 46,000 flights were canceled in a single day. We have short memories for these outages, but as [Thomas] points out, this was far from the first massive outage, and many of them have very strange backstories.

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