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NetBSD Bans AI-Generated Code From Commits

A recent change was announced to the NetBSD commit guidelines which amends these to state that code which was generated by Large Language Models (LLMs) or similar technologies, such as ChatGPT, Microsoft’s Copilot or Meta’s Code Llama is presumed to be tainted code. This amendment was to the existing section about tainted code, which originally referred to any code that was not written directly by the person committing the code, and was due to licensing concerns. The obvious reason behind this is that otherwise code may be copied into the NetBSD codebase which may have been licensed under an incompatible (or proprietary) license.
In the case of LLM-based code generators like the above-mentioned, the problem stems from the fact that they are trained on millions of lines of code from all over the internet, which are naturally released under a wide variety of licenses. Invariably, some of that code will be covered by a license that’s not acceptable for the NetBSD codebase. Although the guideline mentions that these auto-generated code commits may still be admissible, they require written permission from core developers, and presumably an in-depth audit of the code’s heritage. This should leave non-trivial commits that got churned out by ChatGPT and kin out in the cold.
The debate about the validity of works produced by current-gen “artificial intelligence” software is only just beginning, but there’s little question that NetBSD has made the right call here. From a legal and software engineering perspective this policy makes perfect sense, as LLM-generated code simply doesn’t meet the project’s standards. That said, code produced by humans brings with it a whole different set of potential problems. […]

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Winamp Source Code Will be Opened Up, Company Says

Recently the company currently in charge of the Winamp media player – formerly Radionomy, now Llama Group – announced that it will be making the source code of the player ‘available to developers’. Although the peanut gallery immediately seemed to have jumped to the conclusion that this meant that the source would be made available to all on the announced 24 September 2024 date, reading between the lines of the press release gives a different impression.
First there is the sign-up form for ‘FreeLlama’ where interested developers can sign up, with a strong suggestion that only vetted developers will be able to look at the code, which may or may not be accompanied by any non-disclosure agreements. It would seem appropriate to be skeptical considering Winamp’s rocky history since AOL divested of it in 2013 with version 5.666 and its new owner Radionomy not doing much development on the software except for adding NFT and crypto/blockchain features in 2022. The subsequent Winamp online service doubled down on this.
Naturally it would be great to see Winamp become a flourishing OSS project for the two dozen of us who still use Winamp on a daily base, but the proof will be in the non-NFT pudding, as the saying goes. […]

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Emulating Biology For Robots With Rolling Contact Joints

Joints are an essential part in robotics, especially those that try to emulate the motion of (human) animals. Unlike the average automaton, animals are not outfitted with bearings and similar types of joints, but rather rely sometimes on ball joints and a lot on rolling contact joints (RCJs). These RCJs have the advantage of being part of the skeletal structure, making them ideal for compact and small joints. This is the conclusion that [Breaking Taps] came to as well while designing the legs for a bird-like automaton.
These RCJs do not just have the surfaces which contact each other while rotating, but also provide the constraints for how far a particular joint is allowed to move, both in the forward and backward directions as well as sideways. In the case of the biological version these contact surfaces are also coated with a constantly renewing surface to prevent direct bone-on-bone contact. The use of RCJs is rather common in robotics, with the humanoid DRACO 3 platform as detailed in a 2023 research article by [Seung Hyeon Bang] and colleagues in Frontiers in Robotics and AI.
The other aspect of RCJs is that they have to be restrained with a compliant mechanism. In the video [Breaking Taps] uses fishing line for this, but many more options are available. The ‘best option’ also depends on the usage and forces which the specific joint will be subjected to. For further reading on the kinematics in robotics and kin, we covered the book Exact Constraint: Machine Design Using Kinematic Principles by [Douglass L. Blanding] a while ago.

[embedded content] […]

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Is The Frequency Domain a Real Place?

When analyzing data, one can use a variety of transformations on the data to massage it into a form that works better to tease out the information one is interested in. One such example is the application of the Fourier transform, which transforms a data set from the time domain into the frequency domain. Yet what is this frequency domain really? After enticing us to follow the white rabbit down a sudden plummet into the intangible question of what is and what is not, [lcamtuf] shows us around aspects of the frequency domain and kin.
One thing about the (discrete) Fourier transform is that it is excellent at analyzing data that consists out of sinewaves, such as audio signals. Yet when using the Fourier transform for square waves, the resulting output is less than useful, almost as if square waves are not real. Similarly, other transforms exist which work great for square waves, but turn everything else into meaningless harmonics. Starting with the discrete cosine transform (DCT), this gets us into Walsh and Hadamard matrices and the Walsh-Hadamard Transform (WHT), and their usage with transforming data from the time into the frequency domain.
Ultimately it would seem that the frequency domain is as real as it needs to be, albeit that its appearance is wholly dependent on the algorithm used to create it, whether this the DFT, DCT, WHT or something else entirely. […]

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Introduction to MOSFET Switching Losses

Metal-oxide semiconductor field-effect transistors (MOSFETs) see common use in applications ranging from the very small (like CPU transistors) to very large (power) switching applications. Although its main advantage is its high power efficiency, MOSFETs are not ideal switches with a perfect on or off state. Understanding the three main sources of switching losses is crucial when designing with MOSFETs, with a recent All About Circuits article by [Robert Keim] providing a primer on the subject.
As it’s a primer, the subtreshold mode of MOSFET modes of operation is omitted, leaving the focus on the linear (ohmic) mode where the MOSFET’s drain-source is conducting, but with a resistance that’s determined by the gate voltage. In the saturated mode the drain-source resistance is relatively minor (though still relevant), but the turn-on time (RDS(on)) before this mode is reached is where major switching losses occur. Simply switching faster is not a solution, as driving the gate incurs its own losses, leaving the circuit designer to carefully balance the properties of the MOSET.
For those interested in a more in-depth study of MOSFETs in e.g. power supplies, there are many articles on the subject, such as this article (PDF) from Texas Instruments. […]

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The New Extremely Large Telescopes and The US’ Waning Influence In Astronomy

For many decades, the USA has been at the forefront of astronomy, whether with ground-based telescopes or space-based observatories like Hubble and the JWST. Yet this is now at risk as US astronomers are forced to choose between funding either the Giant Magellan Telescope (GMT) or the Thirty Meter Telescope (TMT) as part of the US Extremely Large Telescope (USELT) program. This rightfully has the presidents of Carnegie Science and Caltech – [Eric D. Isaacs] and [Thomas F. Rosenbaum] respectively – upset, with their opinion piece in the Los Angeles Times going over all the reasons why this funding cut is a terrible idea.
The slow death of US astronomy is perhaps best exemplified by the slow death and eventual collapse of the Arecibo radio telescope. Originally constructed as a Cold War era ICBM detector, it found grateful use by radio astronomers, but saw constant budget cuts and decommissioning threats. After Arecibo’s collapse, it’s now China with its FAST telescope that has mostly taken the limelight. In the case of optical telescopes, the EU’s own ELT is expected to be online in 2028, sited close to the GMT in the Atacama desert. The TMT would be sited in Hawai’i.

Of note is also that the TMT and GMT are both not solely US-funded at this point in time, but rather a partnership with a range of other nations, including Australia, South Korea, China, Canada, Japan, India and others. Even if the US only contributes funds to either telescope, the other partners may decide to pick up the slack, however the TMT project is currently in dire straits as the selected site on Mauna Kea has run into severe local resistance. This may force the TMT project to be sited elsewhere.
GMT and ESO’s ELT would seem to overlap significantly in terms of functionality and observed parts of the sky, making the TMT perhaps the most useful choice for US astronomers if they cannot have both. No matter what choice is made, however, it’ll mean more US budget cuts for astronomy and more US astronomers having to schedule observation time at EU and Asian observatories. Ultimately the USA as the guiding star in astronomy may significantly diminish, along with the positive effects of this status in the scientific community. […]

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New Quadcopter Speed World Record Set At Nearly 500 Km/h

Making a quadcopter go fast would seem to be quite simple: just strap on powerful motors, aim the quadcopter roughly at where you want it to go fast, and let ‘er rip. Because of aerodynamics and other pesky physical laws there are a few complications to this, of course, but this didn’t deter [Luke Bell] and his father [Mike Bell] from nailing the Guinness World Record for remote-controlled quadcopters on April 21, 2024. During the official run, a top speed of 480.23 km/h was recorded, making it considerably faster than the first version they made, which hit a measly 400 km/h.
For this second iteration of the ‘got to go fast’ quadcopter, the design was scaled up, with more powerful motors and associated electronics added. Naturally, when you’re pushing brushless motors and their ESCs to their limits, stuff can get a bit hot due to the immense currents flowing through the system. This resulted in a number of battery, wire and other fires. Fortunately, the worrying aspect of in-flight stability got addressed pretty well courtesy of a professional drone trainer, and ultimately the world record attempt went off without a hitch.
An endurance test was also attempted, which reached 7.5 km at 180 km/h, and with the clear canopy in from of the camera removed, visual performance was pretty stunning, while still easily reaching 400 km/h. This might make it the perfect high-speed chase camera system.
Thanks to [Craig] for the tip.

[embedded content] […]

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New Quadcopter Speed World Record Set At Nearly 500 Km/h

Making a quadcopter go fast would seem to be quite simple: just strap on powerful motors, aim the quadcopter roughly at where you want it to go fast, and let ‘er rip. Because of aerodynamics and other pesky physical laws there are a few complications to this, of course, but this didn’t deter [Luke Bell] and his father [Mike Bell] from nailing the Guinness World Record for remote-controlled quadcopters on April 21, 2024. During the official run, a top speed of 480.23 km/h was recorded, making it considerably faster than the first version they made, which hit a measly 400 km/h.
For this second iteration of the ‘got to go fast’ quadcopter, the design was scaled up, with more powerful motors and associated electronics added. Naturally, when you’re pushing brushless motors and their ESCs to their limits, stuff can get a bit hot due to the immense currents flowing through the system. This resulted in a number of battery, wire and other fires. Fortunately, the worrying aspect of in-flight stability got addressed pretty well courtesy of a professional drone trainer, and ultimately the world record attempt went off without a hitch.
An endurance test was also attempted, which reached 7.5 km at 180 km/h, and with the clear canopy in from of the camera removed, visual performance was pretty stunning, while still easily reaching 400 km/h. This might make it the perfect high-speed chase camera system.
Thanks to [Craig] for the tip.

[embedded content] […]

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IRCB S73-7 Satellite Found After Going Untracked For 25 Years

When the United States launched the KH-9 Hexagon spy satellite into orbit atop a Titan IIID rocket in 1974, it brought a calibration target along for the ride: the Infra-Red Calibration Balloon (IRCB) S73-7. This 66 cm (26 inch) diameter inflatable satellite was ejected by the KH-9, but failed to inflate into its intended configuration and became yet another piece of space junk. Initially it was being tracked in the 1970s, but vanished until briefly reappearing in the 1990s. Now it’s popped up again, twenty-five years later.
As noted by [Jonathan McDowell] who tripped over S73-7 in recent debris tracking data, it’s quite possible that it had been tracked before, but hidden in the noise as it is not an easy target to track. Since it’s not a big metallic object with a large radar cross-section, it’s among the more difficult signals to reliably pick out of the noise. As can be seen in [Jonathan]’s debris tracking table, this is hardly a unique situation, with many lost (XO) entries. This always raises the exciting question of whether a piece of debris has had its orbit decayed to where it burned up, ended up colliding with other debris/working satellite or simply has gone dark.
For now we know where S73-7 is, and as long as its orbit remains stable we can predict where it’ll be, but it highlights the difficulty of keeping track of the around 20,000 objects in Earth orbit, with disastrous consequences if we get it wrong. […]

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The Minimalistic Dillo Web Browser Is Back

Over the decades web browsers have changed from the fairly lightweight and nimble HTML document viewers of the 1990s to today’s top-heavy browsers that struggle to run on a system with less than a quad-core, multi-GHz CPU and gigabytes of RAM. All but a few, that is.
Dillo is one of a small number of browsers that requires only a minimum of system resources and will happily run on an Intel 486 or thereabouts. Sadly, the project more or less ended back in 2016 when the rendering engine’s developer passed away, but with the recent 3.10 release the project seems to be back on track, courtesy of efforts by [Rodrigo Arias Mallo].
Although a number of forks were started after the Dillo project ground to a halt, of these only Dillo+ appears to be active at this point in time, making this project revival a welcome boost, as is its porting to Atari systems. As for Dillo’s feature set, it boasts support for a range of protocols, including Gopher, HTTP(S), Gemini, and FTP via extensions. It supports HTML 4.01 and some HTML 5, along with CSS 2.1 and some CSS 3 features, and of course no JavaScript.
On today’s JS-crazed web this means access can be somewhat limited, but maybe it will promote websites to have a no-JS fallback for the Dillo users. The source code and releases can be obtained from the GitHub project page, with contributions to the project gracefully accepted.
Thanks to [Prof. Dr. Feinfinger] for the tip. […]