Audio Localization Gear Built On The Cheap

June 27, 2025 by 11 Comments

Most humans with two ears have a pretty good sense of directional hearing. However, you can build equipment to localize audio sources, too. That’s precisely what [Sam], [Ezra], and [Ari] did for their final project for the ECE4760 class at Cornell this past Spring. It’s an audio localizer!

The project is a real-time audio localizer built on a Raspberry Pi Pico. The Pico is hooked up to three MEMS microphones which are continuously sampled at a rate of 50 kHz thanks to the Pico’s nifty DMA features. Data from each microphone is streamed into a rolling buffer, with peaks triggering the software on the Pico to run correlations between channels to determine the time differences between the signal hitting each microphone. Based on this, it’s possible to estimate the location of the sound source relative to the three microphones.

The team goes into great deal on the project’s development, and does a grand job of explaining the mathematics and digital signal processing involved in this feat. Particularly nice is the heatmap output from the device which gives a clear visual indication of how the sound is being localized with the three microphones.

We’ve seen similar work before, too, like this project built to track down fireworks launches. Video after the break.

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This Week In Security: MegaOWNed, Store Danger, And FileFix

June 27, 2025 by 7 Comments

Earlier this year, I was required to move my server to a different datacenter. The tech that helped handle the logistics suggested I assign one of my public IPs to the server’s Baseboard Management Controller (BMC) port, so I could access the controls there if something went sideways. I passed on the offer, and not only because IPv4 addresses are a scarce commodity these days. No, I’ve never trusted a server’s built-in BMC. For reasons like this MegaOWN of MegaRAC, courtesy of a CVSS 10.0 CVE, under active exploitation in the wild.

This vulnerability was discovered by Eclypsium back in March and it’s a pretty simple authentication bypass, exploited by setting an X-Server-Addr header to the device IP address and adding an extra colon symbol to that string. Send this along inside an HTTP request, and it’s automatically allowed without authentication. This was assigned CVE-2024-54085, and for servers with the BMC accessible from the Internet, it scores that scorching 10.0 CVSS.

We’re talking about this now, because CISA has added this CVE to the official list of vulnerabilities known to be exploited in the wild. And it’s hardly surprising, as this is a near-trivial vulnerability to exploit, and it’s not particularly challenging to find web interfaces for the MegaRAC devices using tools like Shodan and others.

There’s a particularly ugly scenario that’s likely to play out here: Embedded malware. This vulnerability could be chained with others, and the OS running on the BMC itself could be permanently modified. It would be very difficult to disinfect and then verify the integrity of one of these embedded systems, short of physically removing and replacing the flash chip. And malware running from this very advantageous position very nearly have the keys to the kingdom, particularly if the architecture connects the BMC controller over the PCIe bus, which includes Direct Memory Access.

This brings us to the really bad news. These devices are everywhere. The list of hardware that ships with the MegaRAC Redfish UI includes select units from “AMD, Ampere Computing, ASRock, ARM, Fujitsu, Gigabyte, Huawei, Nvidia, Supermicro, and Qualcomm”. Some of these vendors have released patches. But at this point, any of the vulnerable devices on the Internet, still unpatched, should probably be considered compromised. Continue reading “This Week In Security: MegaOWNed, Store Danger, And FileFix” →

Meet Cucumber, The Robot Dog

June 27, 2025 by 6 Comments

Robots can look like all sorts of things, but they’re often more fun if you make them look like some kind of charming animal. That’s precisely what [Ananya], [Laurence] and [Shao] did when they built Cucumber the Robot Dog for their final project in the ECE 4760 class.

Cucumber is controllable over WiFi, which was simple enough to implement by virtue of the fact that it’s based around the Raspberry Pi Pico W. With its custom 3D-printed dog-like body, it’s able to move around on its four wheels driven by DC gear motors, and it can flex its limbs thanks to servos in its various joints. It’s able to follow someone with some autonomy thanks to its ultrasonic sensors, while it can also be driven around manually if so desired. To give it more animal qualities, it can also be posed, or commanded to bark, howl, or growl, with commands issued remotely via a web interface.

The level of sophistication is largely on the level of the robot dogs that were so popular in the early 2000s. One suspects it could be pretty decent at playing soccer, too, with the right hands behind the controls. Video after the break.

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A Cheap Smart Plug To Block Distractions

June 27, 2025 by 19 Comments

We have all suffered from this; the boss wants you to compile a report on the number of paper clips and you’re crawling up the wall with boredom, so naturally your mind strays to other things. You check social media, or maybe the news, and before you know it a while has been wasted. [Neil Chen] came up with a solution, to configure a cheap smart plug with a script to block his diversions of choice.

The idea is simple enough, the plug is in an outlet that requires getting up and walking a distance to access, so to flip that switch you’ve really got to want to do it. Behind it lives a Python script that can be found in a Git Hub repository, and that’s it! We like it for its simplicity and ingenuity, though we’d implore any of you to avoid using it to block Hackaday. Some sites are simply too important to avoid!

Of course, if distraction at work is your problem, perhaps you should simply run something without it.

Animal Crossing keyboard banner

Making GameCube Keyboard Controller Work With Animal Crossing

June 26, 2025 by 2 Comments

[Hunter Irving] is a talented hacker with a wicked sense of humor, and he has written in to let us know about his latest project which is to make a GameCube keyboard controller work with Animal Crossing.

This project began simply enough but got very complicated in short order. Initially the goal was to get the GameCube keyboard controller integrated with the game Animal Crossing. The GameCube keyboard controller is a genuine part manufactured and sold by Nintendo but the game Animal Crossing isn’t compatible with this controller. Rather, Animal Crossing has an on-screen keyboard which players can use with a standard controller. [Hunter] found this frustrating to use so he created an adapter which would intercept the keyboard controller protocol and replace it with equivalent “keypresses” from an emulated standard controller.

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Pi Networks The Smith Chart Way

June 26, 2025 by 10 Comments

[Ralph] is excited about impedance matching, and why not? It is important to match the source and load impedance to get the most power out of a circuit. He’s got a whole series of videos about it. The latest? Matching using a PI network and the venerable Smith Chart.

We like that he makes each video self-contained. It does mean if you watch them all, you get some review, but that’s not a bad thing, really. He also does a great job of outlining simple concepts, such as what a complex conjugate is, that you might have forgotten.

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Two clear acrylic tubes are shown in the foreground. Swirls of sawdust are visible on the inside of the tubes, and the tubes are held in place by grey plastic connectors. Below the tubes, there are two clear plastic tubs containing sawdust.

Optimizing Dust Separation For Extreme Efficiency

June 26, 2025 by 15 Comments

[Ruud], the creator of [Capturing Dust], started his latest video with what most of us would consider a solved problem: the dust collection system for his shop already had a three-stage centrifugal dust separator with more than 99.7% efficiency. This wasn’t quite as efficient as it could be, though, so [Ruud]’s latest upgrade shrinks the size of the third stage while increasing efficiency to within a rounding error of 99.9%.

The old separation system had two stages to remove large and medium particles, and a third stage to remove fine particles. The last stage was made out of 100 mm acrylic tubing and 3D-printed parts, but [Ruud] planned to try replacing it with two parallel centrifugal separators made out of 70 mm tubing. Before he could do that, however, he redesigned the filter module to make it easier to weigh, allowing him to determine how much sawdust made it through the extractors. He also attached a U-tube manometer (a somewhat confusing name to hear on YouTube) to measure pressure loss across the extractor.

The new third stage used impellers to induce rotational airflow, then directed it against the circular walls around an air outlet. The first design used a low-profile collection bin, but this wasn’t keeping the dust out of the air stream well enough, so [Ruud] switched to using plastic jars. Initially, this didn’t perform as well as the old system, but a few airflow adjustments brought the efficiency up to 99.879%. In [Ruud]’s case, this meant that of 1.3 kilograms of fine sawdust, only 1.5 grams of dust made it through the separator to the filter, which is certainly impressive in our opinion. The design for this upgraded separator is available on GitHub.

[Ruud] based his design off of another 3D-printed dust separator, but adapted it to European fittings. Of course, the dust extractor is only one part of the problem; you’ll still need a dust routing system.

Thanks to [Keith Olson] for the tip!