2024 Home Sweet Home Automation: Spray Bottle Turret Silences Barking

April 26, 2024 by Kristina Panos 11 Comments

Ah, dogs. They sure like to bark, don’t they? [rrustvold]’s dog likes to bark at the door when a package arrives. Or when someone walks by the house, or whenever the mood strikes, really. To solve the barking issue, at least near the front door, [rrustvold] built a spray bottle turret to teach the dog through classical conditioning.

As you can see from the image, it’s all about pulling the trigger on a standard spray bottle at the right time. This machine only sprays when two conditions are met: it hears noise (like barking) and detects motion (like overzealous tail wagging). It also has heat-seeking abilities thanks to a Raspberry Pi thermal camera.

To do the actual spraying, there’s a DC motor mounted behind the bottle which turns a pulley that’s mounted to its shaft. Around the pulley is a string that wraps around the spray bottle’s trigger. To complete the build, everything is mounted on a lazy Susan so there’s nowhere for Fido to hide-o.

If you’ve a dog whose bite is worse than its bark, consider building a custom dog door to keep it out of the cat box.

The 2024 Home Sweet Home Automation contest has officially wrapped — we’re counting the votes now, so stay tuned for an announcement about the winners shortly.

This Week In Security: Cisco, Mitel, And AI False Flags

April 26, 2024 by Jonathan Bennett 3 Comments

There’s a trend recently, of big-name security appliances getting used in state-sponsored attacks. It looks like Cisco is the latest victim, based on a report by their own Talos Intelligence.

This particular attack has a couple of components, and abuses a couple of vulnerabilities, though the odd thing about this one is that the initial access is still unknown. The first part of the infection is Line Dancer, a memory-only element that disables the system log, leaks the system config, captures packets and more. A couple of the more devious steps are taken, like replacing the crash dump process with a reboot, to keep the in-memory malware secret. And finally, the resident installs a backdoor in the VPN service.

There is a second element, Line Runner, that uses a vulnerability to arbitrary code from disk on startup, and then installs itself onto the device. That one is a long term command and control element, and seems to only get installed on targeted devices. The Talos blog makes a rather vague mention of a 32-byte token that gets pattern-matched, to determine an extra infection step. It may be that Line Runner only gets permanently installed on certain units, or some other particularly fun action is taken.

Fixes for the vulnerabilities that allowed for persistence are available, but again, the initial vector is still unknown. There’s a vulnerability that just got fixed, that could have been such a vulnerability. CVE-2024-20295 allows an authenticated user with read-only privileges perform a command injection as root. Proof of Concept code is out in the wild for this one, but so far there’s no evidence it was used in any attacks, including the one above. Continue reading “This Week In Security: Cisco, Mitel, And AI False Flags” →

AI System Drops A Dime On Noisy Neighbors

April 25, 2024 by Dan Maloney 4 Comments

“There goes the neighborhood” isn’t a phrase to be thrown about lightly, but when they build a police station next door to your house, you know things are about to get noisy. Just how bad it’ll be is perhaps a bit subjective, with pleas for relief likely to fall on deaf ears unless you’ve got firm documentation like that provided by this automated noise detection system.

OK, let’s face it — even with objective proof there’s likely nothing that [Christopher Cooper] is going to do about the new crop of sirens going off in his neighborhood. Emergencies require a speedy response, after all, and sirens are perhaps just the price that we pay to live close to each other. That doesn’t mean there’s no reason to monitor the neighborhood noise, though, so [Christopher] got to work. The system uses an Arduino BLE Sense module to detect neighborhood noises and Edge Impulse to classify the sounds. An ESP32 does most of the heavy lifting, including running the UI on a nice little TFT touchscreen.

When a siren-like sound is detected, the sensor records the event and tries to classify the type of siren — fire, police, or ambulance. You can also manually classify sounds the system fails to understand, and export a summary of events to an SD card. If your neighborhood noise problems tend more to barking dogs or early-morning leaf blowers, no problem — you can easily train different models.

While we can’t say that this will help keep the peace in his neighborhood, we really like the way this one came out. We’ve seen the BLE Sense and Edge Impulse team up before, too, for everything from tuning a bike suspension to calming a nervous dog. Continue reading “AI System Drops A Dime On Noisy Neighbors” →

The MUSE Permanent Magnet Stellarator: Fusion Reactor With Off-The-Shelf Parts

April 21, 2024 by Maya Posch 24 Comments

(a) The 12 permanent magnet holder subsegments. (b) The 16 planar, circular toroidal field coils are positioned inside the water-jet cut support structure. (c) The glass vacuum vessel is joined by 3D-printed low-thickness couplers. Glass ports were hot welded to the torus. (Credit: T.M. Qian et al., 2023)

When you think of a fusion reactor like a tokamak or stellarator, you are likely to think of expensive projects requiring expensive electromagnets made out of exotic alloys, whether superconducting or not. The MUSE stellarator is an interesting study in how to take things completely in the opposite direction. Its design and construction is described in a 2023 paper by [T.M. Qian] and colleagues in the Journal of Plasma Physics. The theory is detailed in a 2020 Physical Review Letters paper by [P. Helander] and colleagues. As the head of the Stellarator Theory at the Max Planck Institute, [P. Helander] is well-acquainted with the world’s most advanced stellarator: Wendelstein 7-X.

As noted in the paper by [P. Helander] et al., the use of permanent magnets can substantially simplify the magnetic-field coils of a stellarator, which are then primarily used for the toroidal magnetic flux. This simplification is reflected in the design of MUSE, as it only has a limited number of identical toroidal field coils, with the vacuum vessel surrounded by 3D printed structures that have permanent magnets embedded in them. These magnets follow a pattern that helps to shape the plasma inside the vacuum vessel, while not requiring a power supply or (at least theoretically) cooling.

Naturally, as noted by [P. Helander] et al, a limitation of permanent magnets is their limited field strength, inability to be tuned, and demagnetization at high temperatures. This may limit the number of practical applications of this approach, but researchers at Princeton Plasma Physics Laboratory (PPPL) recently announced in a self-congratulatory article that they will ‘soon’ commence actual plasma experiments with MUSE. The lack of (cooled) divertors will of course limit the experiments that MUSE can be used for.

Bad Experiences With A Cheap Wind Turbine

April 20, 2024 by Lewin Day 44 Comments

If you’ve got a property with some outdoor space and plenty of wind, you might consider throwing up a windmill to generate some electricity. Indeed, [The Broject List] did just that. Only, his experience was a negative one, having purchased a cheap windmill online. He’s warning off others from suffering the same way by explaining what was so bad about the product he bought.

The windmill in question was described as a “VEVOR Windturbine”, which set him back around 100 euros, and claimed to be capable of producing 600 watts at 12 volts. He starts by showing how similar turbines pop up for sale all over the Internet, with wildly inflated specs that have no relation to reality. Some sellers even charge over 500 euros for the same basic device.

He then demonstrates the turbine operating at wind speeds of approximately 50 km/h. The output is dismal, a finding also shared by a number of other YouTube channels out there. Examining the construction of the wind turbine’s actual generator, he determines that it’s nowhere near capable of generating 600 watts. He notes the poorly-manufactured rotor and aluminium coils as particular disappointments. He concludes it could maybe generate 5 watts at most.

Sadly, it’s easy to fall into this trap when buying online. That’s where it pays to do your research before laying down your hard-earned cash. Continue reading “Bad Experiences With A Cheap Wind Turbine” →

Hackaday Podcast Episode 267: Metal Casting, Plasma Cutting, And A Spicy 555

April 19, 2024 by Al Williams 3 Comments

What were some of the best posts on Hackaday last week? Elliot Williams and Al Williams decided there were too many to choose from, but they did take a sampling of the ones that caught their attention. This week’s picks were an eclectic mix of everything from metal casting and plasma cutters to radio astronomy and space telescope budgets. In between? Some basic circuit design, 3D printing, games, dogs, and software tools. Sound confusing? It won’t be, after you listen to this week’s podcast.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download an audiophile-quality oxygen-free MP3 file here.

Continue reading “Hackaday Podcast Episode 267: Metal Casting, Plasma Cutting, And A Spicy 555” →

Source Code To The 1999 FPS Game Descent 3 Released

April 17, 2024 by Maya Posch 48 Comments

On April 16th of this year, [Kevin Bentley] released the source code to the Sci-Fi FPS game Descent 3. Originally released in 1999 for Windows, the game has you control a flying ship which you have to guide through both in- and outdoor environments, while shooting at robots that have been infected with an alien virus as you try to save the solar system. It was later also ported to Mac OS and Linux, but was considered a commercial flop due to low sales.

As one of the original developers, [Kevin] explains that one of the goals of this code release is to give the game a second life, by cleaning up the C++ code and using new APIs. Original proprietary audio and video libraries from Interplay were removed, which means that some work is required before one can build a fresh copy of the game from this code base. That said, the released code is the latest 1.5 patch level, with the Mac OS and Linux support. Even if the original Descent games weren’t your cup of tea, it’s still great to see games being preserved and updated like this.

Thanks to [Phil Ashby] for the tip.