Year: 2022

Accessible Arduino Mouse Helps

April 6, 2022 by 3 Comments

We enjoy access to cheap stuff because of the mass market for things like mice, keyboards, and cell phones. But if you need a device that doesn’t have mass appeal, you will have to pay a lot more if you can find it at all. However, with modern techniques like 3D printing and Arduino-like microcontrollers being cheap and simple to use, you now have the option to build that special one-of-a-kind device. Case in point: [Davy’s] mouse for people who have brain or nervous system disorders. This particular device is helping a 6-year-old who can’t manipulate a normal mouse.

The device uses an Arduino Pro and an MPU-6050 accelerometer and gyroscope. The original design uses machined aluminum, but 3D printing should work, too. There’s something wrong with the link to the design files in the post, but it is easy to find the correct link.

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Hacking A Fuel Sensor Into A Portable Tank, Literally

April 6, 2022 by 23 Comments

Regular readers of Hackaday will know that the projects we feature are generally of the high-tech variety. Microcontrollers, 3D printed parts, embedded Linux, lots of wires, that sort of thing. But that’s not to say we don’t appreciate the somewhat more visceral builds out there; after all, hacking is about creative problem solving and thinking outside the box, and none of that is limited to how complex the fix actually is.

Take for example this quick hack that [R. Preston McAfee] recently sent our way. Looking for a way to check how much fuel was left in his outboard motor’s small portable gas tank without crawling back to look at it, he decided to rig it up with a sending unit. While they’re technically designed for larger tanks which are permanently installed into a boat’s hull, he reasoned there was nothing about the float sensor that would keep it from working in his case so long as it could be safely mounted.

To that end, [Preston] started by cutting a 38 mm (1.5″) hole in the thickest part of the tank, and sanded the area around the opening to smooth things out. He then measured the depth of the tank at that point, and ordered an appropriately sized float sensor. He drilled out the holes for the five mounting bolts, and inserted them through the larger whole so their heads would be inside the tank. By holding the exposed threads with a pair of vice grips he was able to crank the nuts down on each bolt to form a tight seal to the gasket, though it should be noted that the resulting damage to the threads will likely make it difficult to remove the nuts in the future.

Admittedly this is a pretty simple fix, but it’s well thought-out and we appreciate the effort [Preston] put in to documenting the whole process. We’ve certainly covered more elaborate ways of seeing what’s left in the tank, but just because a solution is flashier doesn’t mean it’s necessarily any better.

Pong In Hardware… Virtually

April 6, 2022 by 5 Comments

We are big fans of the Falstad circuit simulator. Sure, it isn’t perfect, but there’s nothing else like it when you want to whip up a simple circuit. But we were blown away when we saw a more or less complete hardware implementation of Pong in Falstad. No kidding. Starting with the original schematics, there are multiple pages that show each sub-circuit and even a playable subset that you can play the game in your browser.

But wait… you probably noticed there’s no CRT display in the simulator’s component menu. That’s true, there isn’t. However, you can write JavaScript to interact with a running simulation, so the display is a simple bit of JavaScript that samples signals at predetermined points and does the appropriate drawings. There’s even audio output for the sound effects, although that is built into the simulator.

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Whales Help Scientists Investigate The Mystery Of Menopause

April 6, 2022 by 7 Comments

Menopause is the time of life when menstrual periods come to a halt, and a woman is no longer able to bear children. The most obvious cause of menopause is when the ovaries run out of eggs, though it can also be caused by a variety of other medical processes. While menopause is in many ways well-understood, the biological reason for menopause, or the way in which it evolved in humanity remains a mystery. The process was once thought to be virtually non-existent in the animal kingdom, raising further questions.

Surprisingly recently, however, scientists began to learn that humans are not alone in this trait. Indeed, a small handful of sea-going mammals also go through this unique and puzzling process.

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Magnetic Hockey Game Uses A 555

April 6, 2022 by 1 Comment

We love a good project here at Hackaday, particularly one that makes us want to pick it up and have a go at whatever it does for ourselves. And when we see such a project and find that it contains the One Chip To Rule Them All (otherwise known as the NE555 timer), our collective cup runneth over with joy. So [Andrew Fentem]’s magnetic hockey project certainly pushes all our buttons, as it’s a game superficially similar to an air hockey table in which a magnetic puck is accelerated by a handheld electronic bat.

The bats look extremely high-tech but are in fact surprisingly simple. Each one contains a Hall effect sensor which triggers the 555 which we’d expect is wired as a monostable, this in turn fires a MOSFET which energises an electromagnet for a set period of time. The puck is a magnet, and thus when it is detected by the Hall sensor it is shot away at high speed by the electromagnet. the result is a fast-paced game which has an extra edge over conventional air hockey, and which being honest, we’d love to have a go at. You can see it in the video below the break.

Of course, if your budget doesn’t stretch to not one but two chips in this era of semiconductor shortages, you can always try a conventional table.

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Bath County Pumped Storage Station (Credit: CHA)

Grid-Level Energy Storage And The Challenge Of Storing Energy Efficiently

April 6, 2022 by 118 Comments

Although every electrical grid begins with the production of electricity, there are times when storing this power in some form instead of using it immediately is highly convenient. Today’s battery-powered gadgets are an obvious example of such time-shifting, but energy storage plays a major role on the grid itself, too, whether in electrochemical, mechanical or in some other form.

Utility-level energy storage is essential for not only stabilizing the grid, but also to time-shift excess energy and provide a way to deal with sudden spikes in demand (peak-shaving) plus demand drops by absorbing the excess energy. The health of the grid can essentially be regarded as a function of its alternating current (AC) frequency, with strong deviations potentially leading to a collapse of the grid.

Naturally, such energy storage is not free, and the benefits of adding it to the grid have to be considered against the expense, as well as potential alternatives. With the rapid increase of highly volatile electrical generators on the grid in the form of non-dispatchable variable renewable energy, e.g. wind turbines and PV solar, there has been a push to store more excess power rather than curtailing it, in addition to using energy storage for general grid health.

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Helping The War Effort With 3D Printed Tourniquets

April 6, 2022 by 32 Comments

It’s a sad statement on the modern world that even civilians are at risk for severe traumatic injuries in the course of going about their lives. And if something unthinkable happens to you or someone you love, here’s hoping both that the injury can be treated, and that someone is nearby who both knows what to do and is properly equipped to do it.

That’s the thinking behind these 3D printed tourniquets, an unfortunate but necessary response to the ongoing war in Ukraine. To get tourniquets into the hands of those trained to use them, [3DPrintingforUkraine] is working on plans for a printable version of the C-A-T, or combat application tourniquet, a lightweight but strong tourniquet that can be rapidly applied, even by victims themselves. The commercial device consists of molded nylon buckles and hook-and-loop fastener bands, along with a very sturdy plastic handle that serves as a windlass that provides the necessary occlusive force when twisted. The 3D printed version’s parts aren’t as streamlined as the commercial unit’s, but they appear to be strong enough to withstand the considerable forces involved. From the look of their site, STL files and instructions for assembly will be available soon.

To be clear, tourniquets should only be applied by someone properly trained to do so. But having ample tourniquets available where traumatic injuries to the extremities are likely to occur can only improve the odds that one will be available when it’s needed. So hats off to [3DPrintingforUkraine] for making the effort to push this forward.

[Austin Everman] sent us this tip. Thanks!