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Old Windsurfers Become New Electric Surfboards

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Windsurfing has experienced a major decline in popularity in the last few decades as the sport’s culture failed to cater to beginners at the same time that experienced riders largely shifted to kiteboarding. While it’s sad to see a once-popular and enjoyable sport loose its mass market appeal, it does present a unique opportunity for others as there’s cheap windsurfing gear all over the online classifieds now. [Dane] recently found that some of these old boards are uniquely suited to be modified into electric surfboards . The key design element of certain windsurfers that makes this possible is the centerboard, a fin mounted on the windsurfer extending down into the water that resists the lateral force of the sail, keeping the board moving forward instead of sideways. [Dane] used this strengthened area of the board to mount a submerged electric motor, with all of the control electronics and a battery on the top of the board. The motor controller did need a way to expel excess heat wh...

Hacking the Krups Cook4Me Smart Cooking Pot for Doom

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With more and more kitchen utilities gaining touch screens and capable microcontrollers it’d be inconceivable that they do not get put to other uses as well. To this end [Aaron Christophel] is back with another briefly Doom -less device in the form of the Krups Cook4Me pressure cooking pot with its rather sizeable touch screen and proclaimed smarts in addition to WiFi and an associated smartphone app. Inside is an ESP32 module for the WiFi side, with the brains of the whole operation being a Renesas R7S721031VC SoC with a single 400 MHz Cortex-A9. This is backed by 128 MB of Flash and 128 MB of RAM. The lower touch interface is handled by a separate Microchip PIC MCU to apparently enable for low standby power usage until woken up by touch. The developers were nice enough to make it easy to dump the firmware on the SoC via SWD, allowing for convenient reverse-engineering and porting of Doom. With the touch screen used as the human input device it was actually quite playable, and co...

Playing Factorio on a Floppy Disk Cluster

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While a revolutionary storage system for their time, floppy disks are not terribly useful these days. Though high failure rates and slow speeds are an issue, for this project, the key issue is capacity. That’s because [DocJade’s] goal is playing the video game Factorio off floppy disks.  Storing several gigabytes of data on floppy disks is a rather daunting challenge. But instead of using a RAID array, only a single reader and a custom file system is deployed in this setup. A single disk is dedicated to storing pool information allowing for caching of file locations, reducing disk swaps. The file system can also store single files across multiple disks for storage of larger files. Everything mounts in fuse and is loosely POSIX compliment, but lacks some features like permissions and links. With the data stored across thousands of disks, the user is prompted to insert a new disk when needed. This ends up being the limiting factor in read and write speeds, rather than the famousl...

Finding A Way To Produce Powerful Motors Without Rare Earths

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The electric vehicle revolution has created market forces to drive all sorts of innovations. Battery technology has progressed at a rapid pace, and engineers have developed ways to charge vehicles at ever more breakneck rates. Similarly, electric motors have become more powerful and more compact, delivering greater performance than ever before. In the latter case, while modern EV motors are very capable things, they’re also reliant on materials that are increasingly hard to come by. Most specifically, it’s the rare earth materials that make their magnets so good. The vast majority of these minerals come from China, with trade woes and geopolitics making it difficult to get them at any sort of reasonable price. Thus has sprung up a new market force, pushing engineers to search for new ways to make their motors compact, efficient, and powerful. Rare Many of us first came across neodymium magnets as a simple curiosity. Credit: XRDoDRX , CC BY-SA 3.0 Rare earth materials have becom...

Optimizing a Desktop, 3D Printed Wind Tunnel

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You’ve heard of wind tunnels– get some airflow going over a thingy, put some some smoke on, and voila! Flow visualization. How hard could it be? Well, as always, the devil is in the details and [toast] is down in there with him with this Hot-Wheels sized wind tunnel video. To get good, laminar flow inside of a wind tunnel, there are important ratios to be followed– the inlet and outlet diameters must relate to the interior size to get the correct slope on the contraction and exhaust cones. You need a flow straightener on both ends. All of it can be easily 3D printed, as [toast] shows, but you have to know those design rules and pay attention to, which [toast] does… this time. One of his “don’t do this” examples in this video is previous build of his where he did not follow all the rules, and the difference is clear. Now, unless you’re hooked on flow visualizations — guilty — or are a Hot-Wheels aficionado, since that’s what this wind tunnel is sized for, you probably won’t rush to g...

The Distroless Linux Future May Be Coming

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Over the decades the number of Linux distributions has effectively exploded, from a handful in the late ’90s to quite literally hundreds today, not counting minor variations. There lately seems to be a counter-movement brewing in response to this fragmentation, with Project Bluefin’s Distroless project being the latest addition here. Also notable are KDE’s efforts, with KDE Linux as its own top-down KDE-based distro, but now with a switch to BuildStream from Arch likely as a distroless move. It should be clear that there is no obvious course here yet, and that opinions are very much divided. The idea of ‘Linux’ becoming a more singular OS appeals to some, while to others it’s the antithesis of what ‘Linux’ is about. This much becomes clear in [Brodie Robertson]’s exploration of this topic as well. The way to think about ‘distroless’ is that there is a common base using the Freedesktop SDK on which the customization layer is applied, such as Bluefin, KDE or Gnome’s environments....

Michelson Interferometer Comes Home Cheap

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We suspect there are three kinds of people in the world. People who have access to a Michelson Interferometer and are glad, those who don’t have one and don’t know what one is, and a very small number of people who want one but don’t have one. But since  [Longest Path Search] built one using 3D printing , maybe the third group will dwindle down to nothing. If you are in the second camp, a Michelson interferometer is a device for measuring very small changes in the length of optical paths (oversimplifying, a distance). It does this by splitting a laser into two parts. One part reflects off a mirror at a fixed distance from the splitter. The other reflects off another, often movable, mirror. The beam splitter also recombines the two beams when they reflect back, producing an interference pattern that varies with differences in the path length between the splitter and the mirror. For example, if the air between the splitter and one mirror changes temperature, the change in the refra...