What One-Winged Squids Can Teach The Airship Renaissance

It’s a blustery January day outside Lakehurst, New Jersey. The East Coast of North America is experiencing its worst weather in decades, and all civilian aircraft have been grounded the past four days, from Florida to Maine. For the past two days, that order has included military aircraft, including those certified “all weather” – with one notable exception. A few miles offshore, rocking and bucking in the gales, a U.S. Navy airship braves the storm. Sleet pelts the plexiglass windscreen and ice sloughs off the gasbag in great sheets as the storm rages on, and churning airscrews keep the airship on station.

If you know history you might be a bit confused: the rigid airship USS Akron was lost off the coast of New Jersey, but in April, not January. Before jumping into the comments with your corrections, note the story I’ve begun is set not in 1933, but in 1957, a full generation later.

The airship caught in the storm is no experimental Zeppelin, but an N-class blimp, the workhorse of the cold-war fleet. Yes, there was a cold war fleet of airships; we’ll get to why further on. The most important distinction is that unlike the last flight of the Akron, this story doesn’t end in tragedy, but in triumph. Tasked to demonstrate their readiness, five blimps from Lakehurst’s Airship Airborne Early-Warning Squadron 1 remained on station with no gaps in coverage for the ten days from January 15th to 24th. The blimps were able to swap places, watch-on-watch, and provide continuous coverage, in spite of weather conditions that included 60 knot winds and grounded literally every other aircraft in existence at that time. Continue reading “What One-Winged Squids Can Teach The Airship Renaissance”

Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Uni-body That Does The Splits

Personally, I love a monoblock or uni-body split. You’ll pry this Kinesis Advantage from under my cold, dead hands. But on the go, I really like the Glove 80, a true split that can be completely wireless in case you want to put the halves really far apart.

A triple-black split keyboard without a case, for now.
Image by [thehaikuza] via reddit
[thehaikuza] is the opposite, preferring a full split at the desk, but finding it troublesome when using it on the couch or at a cafe or co-working space, and so created dǎ bāo (打包) — a uni-body split that can also be a distant split. And this best-of-both worlds creation is remarkably [thehaikuza]’s first keyboard.

The name means to take out food, and if you click the picture you can see a cute little take-out container on the silkscreen of the right half. Directly below it, there’s a track point nubbin to be used with the thumb.

It does its split-in-half trick via a magnetic four-pin connector for when you want the halves stuck together. When the halves are separated, they can instead talk over a USB-C cable. One half has the microcontroller, and the other has a GPIO expander.

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Railguns: Making Metal Go Fast Using The Lorentz Force

In science fiction, the use of gunpowder-based weapons is generally portrayed as something from a savage past, with technology having long since moved on to more civilized types of destructive weaponry, involving lasers, microwaves, and electromagnetism. Instead of messy detonating powder, energy-weapons are used to near-instantly deposit significant amounts of energy into the target, and railguns enable the delivery of projectiles at many times the speed of sound using nothing but the raw power of electricity and some creative physics.

Of course, the reason that we don’t see sci-fi weapons deployed everywhere has arguably less to do with today’s levels of savagery in geopolitics and more with the fact that physical reality is a very harsh mistress, who strongly frowns upon such flights of fancy.

Similarly, the Lorentz force that underlies railguns is extremely simple and effective, but scaled up to weapons-grade dimensions results in highly destructive forces that demolish the metal rails and other components of the railgun after only a few firings. Will we ever be able to fix these problems, or are railguns and similar sci-fi weapons forever beyond our grasp?

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Tech In Plain Sight: Projection Clocks

You wake up in the middle of the night. Is it time to get up? Well, you can look at the nightstand clock. Unless your partner is in the way. Whoops. Even then, without your glasses, the time is just a fuzzball of light. You could ask Alexa, but that’s sure to wake your partner, too. The answer is a projection clock. In its modern form, it shoots a digital time display on a wall or ceiling with digits so large that you don’t need your glasses. If you can see the ceiling, you can tell what time it is.

New Tech

A modern invention, of course. No, not really. According to [Roger Russel], a UK patent in 1909 used an analog clock face and lightbulbs to project the clock face and hands on the ceiling. Unfortunately, [Roger’s] website is no more, but the Wayback Machine is on the job. You can see a device of the same type at the British Museum.

A modern projection clock on the ceiling.

In 1938, [Leendert Prins] filed for a patent on a similar projection clock. Sometimes known as “ceiling clocks” or “night clocks,” these devices often have a regular clock visible as well as a way to project the time. In the old days, this was often an image of a translucent analog clock lit up by light bulbs. In the modern era, it is almost always either LEDs or an LCD with a halogen backlight. Of course, there are many variations. A clock might use numbers on a rotating drum with a lamp behind it, for example.

Development

It isn’t hard to imagine someone putting a pocket watch in a magic lantern as a prototype. In general, some bright light source has to pass through a condenser lens. The light then travels through the LCD or translucent clock face. Finally, a projector lens expands the image.

We couldn’t find much about the actual history of old projection clocks outside of [Roger’s] defunct website. But if you can project an image and build a clock, all you need is the idea to combine them.

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How Safe Are Old Airbags, Anyway?

Automotive airbags are key safety devices that aim to reduce injuries and mortality in the event of motor vehicle accidents. These rapidly-inflating cushions act to soften the blow of an impact, catching occupants of the vehicle and preventing them from hitting hard parts of the vehicle’s interior.

Airbags are rigorously tested to perform as faultlessly as possible under all conditions. However, no system is perfect, and every automotive component has an expected service life. The question is—how old is too old when it comes to airbags? The answer is not exactly straightforward.
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In Praise Of The Proof Of Concept

Your project doesn’t necessarily have to be a refined masterpiece to have an impact on the global hacker hivemind. Case in point: this great demo of using a 64-point time-of-flight ranging sensor. [Henrique] took three modules, plugged them into a breadboard, and wrote some very interactive Python code that let him put them all through their paces. The result? I now absolutely want to set up a similar rig and expand on it.

That’s the power of a strong proof of concept, and maybe a nice video presentation of it in action. What in particular makes [Henrique]’s POC work is that he’s written the software to give him a number of sliders, switches, and interaction that let him tweak things in real time and explore some of the possibilities. This exploratory software not only helped him map out what directions to go, but they also work in demo mode, when he’s showing us what he has learned.

But the other thing that [Henrique]’s video does nicely is to point out the limitations of his current POC. Instantly, the hacker mind goes “I could work that out”. Was it strategic incompleteness? Either way, I’ve been nerd-sniped.

So are those the features of a good POC? It’s the bare minimum to convey the idea, presented in a way that demonstrates a wide range of possibilities, and leaving that last little bit tantalizingly on the table?

Ask Hackaday: Do You Have A Dead Man’s Switch?

During the Cold War, the specter of a nuclear “dead man’s switch” was central to the concept of Mutually Assured Destruction (MAD). In the event that one side was annihilated by the other, an automated system would be triggered to deliver a revenge strike that would ultimately destroy the attacker. It was the ultimate defense, as your enemy will never attack if they know doing so will inevitably lead to their own destruction.

The same idea has occasionally been employed by whistleblowers and journalists as well. Should the individual fail to check in regularly, a series of predetermined events will be set into motion. Again, the idea is defensive in nature. If somebody is in possession of information so damning that they could be abducted or even killed to keep it quiet, making arrangements to have that information be released to the public in the event anything should happen to them is a great way to stay safe.

A nuclear dead man’s switch is a key plot point in Dr. Strangelove.

But what about for the average person? In the past, there was no need for most people to think about something as elaborate as a dead man’s switch. But we live in interesting times, to say the least. In an information society such as ours, whistleblowers have never been more common, and the Internet has significantly blurred the definition of what it means to be a journalist.

For those living under a repressive regime or in a war zone, simply posting to social media can provide the outside world with an unfiltered look at what’s actually happening on the ground. A teenager with a cell phone has the potential to reach a wider audience than the legacy media — a powerful, but dangerous, proposition.

Even if you’re not in the middle of political upheaval, there are still reasons you might want to have previously secret information made available in the event of your death or incapacitation. Perhaps you’d like to send your loved ones a final personal message, or make sure the passwords for all your accounts get in the hands of whoever will be handling your estate.

Of course, one could argue that could be accomplished with little more than a notebook hidden in your sock drawer. But this is Hackaday, and over-engineering is the name of the game. So do you have a dead man’s switch? How is it implemented? Or is the whole idea just a bit too out there for you?

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