Why You Can’t Make A Wearable Display With A Transparent OLED

August 19, 2021 by 37 Comments

After seeing the cheap transparent OLED displays that have recently hit the market, you might have thought of using them as an affordable way to build your own wearable display. To save you the inevitable disappointment that would result from such a build, [Zack Freedman] took it upon himself to test out the idea, and show why transparent wearable displays are a harder than it looks.

He put together a headband with integrated microcontroller that holds the transparent OLED over the user’s eye, but unfortunately, anything shown on the display ends up being more or less invisible to the wearer. As [Zack] explains in the video after the break, the human eye is physically incapable of focusing on any object at  such a short distance. Contrary to what many people might think, the hard part of wearable displays is not in the display itself, but rather the optics.  For a wearable display to work, all the light beams from the display need to be focused into your eyeball by lenses and or reflectors, without distorting your view of everything beyond the lens. This requires, lightweight and distortion-free collimators and beam splitters, which are expensive and hard to make.

While these transparent OLEDs might not make practical heads-up displays, they are still a cool part for projects like a volumetric display. It’s certainly possible to build your own smart glasses or augmented reality glasses, you just need to focus on getting the optics right.

Golden Rice’s Appearance On Philippine Store Shelves And The Rise Of Biofortification

August 18, 2021 by 45 Comments

After decades in development, the Philippines became the first country on July 21st of this year to formally approve the commercial propagation of so-called golden rice. This is a rice strain that has been genetically engineered to produce beta-carotene in its grains. This is the same compound that has made carrots so famous, and is a significant source of vitamin A.

Getting enough vitamin A is essential for not only children and newborns, but also for pregnant and lactating women. Currently, vitamin A deficiency (VAD) is the primary cause of preventable childhood blindness and an important cause of infant mortality. While VAD is hardly the only major form of world-wide malnutrition, biofortification efforts like golden rice stand to dramatically improve the lives of millions of people around the globe by reducing the impact of VAD.

This raises questions of how effective initiatives like golden rice are likely to be, and whether biofortification of staple foods may become more common in the future, including in the US where fortification of foods has already become commonplace. Continue reading “Golden Rice’s Appearance On Philippine Store Shelves And The Rise Of Biofortification” →

Teardown: 3D Printed Space Shuttle Lamp

August 17, 2021 by 14 Comments

Since the very beginning, the prevailing wisdom regarding consumer desktop 3D printers was that they were excellent tools for producing prototypes or one-off creations, but anything more than that was simply asking too much. After all, they were too slow, expensive, and finicky to be useful in a production setting. Once you needed more than a few copies of a plastic part, you were better off biting the bullet and moving over to injection molding.

But of course, things have changed a lot since then. Who could have imagined that one day you’d be able to buy five 3D printers for the cost of the crappiest Harbor Freight mini lathe? Modern 3D printers aren’t just cheaper either, they’re also more reliable and produce higher quality parts. Plus with software like OctoPrint, managing them is a breeze. Today, setting up a small print farm and affordably producing parts in mass quantities is well within the means of the average hobbyist.

Space shuttle lamp
Flickering LEDs provide a sense of motion

So perhaps I shouldn’t have been so surprised when I started seeing listings for these 3D printed rocket lamps popping up on eBay. Available from various sellers at a wide array of price points depending on how long you’re willing to wait for shipping, the lamps come in several shapes and sizes, and usually feature either the Space Shuttle or mighty Saturn V perched atop a “exhaust plume” of white PLA plastic. With a few orange LEDs blinking away on the inside, the lamp promises to produce an impressive flame effect that will delight space enthusiasts both young and old.

As a space enthusiast that fits somewhere in between those extremes, I decided it was worth risking $30 USD to see what one of these things looked like in real life. After waiting a month, a crushed up box arrived at my door which I was positive would contain a tiny mangled version of the majestic lamp I was promised — like the sad excuse for a hamburger that McBurgerLand actually gives you compared to what they advertise on TV.

But in person, it really does look fantastic. Using internally lit 3D printed structures to simulate smoke and flame is something we’ve seen done in the DIY scene, but pulling it off in a comparatively cheap production piece is impressive enough that I thought it deserved a closer look.

Now it’s always been my opinion that the best way to see how something was built is to take it apart, so I’ll admit that the following deviates a bit from the rest of the teardowns in this series. There’s no great mystery around flickering a couple LEDs among Hackaday readers, so we already know the electronics will be simplistic in the extreme. This time around the interesting part isn’t what’s on the inside, but how the object itself was produced in the first place.

Continue reading “Teardown: 3D Printed Space Shuttle Lamp” →

Solving Ultra High Vacuum Leaks Has An Elementary Solution

August 16, 2021 by 34 Comments

When we think of a vacuum leak we generally think of a car that just doesn’t want to run quite right. Most normally aspirated internal combustion engines rely on the vacuum created by the pistons to draw in the air fuel mixture that’s produced by the carburetor or fuel injection system. Identifying the leak usually involves spraying something combustible around common trouble areas while the engine is running. Changes to the engine speed indicate when the combustible gas enters the intake manifold and the leak can be found.

What if your vacuum leak is in a highly specialized piece of scientific equipment where the pressures are about 12 times orders of magnitude lower than atmospheric pressure, and the leak is so small it’s only letting a few atoms into the vacuum chamber at a time? [AlphaPhoenix] takes dives deep into this very subject in his video “Air-tight vs. Vacuum-tight.” which you can watch below the break.

Not only does [AlphaPhoenix] discuss how a perfect pressure vessel is sealed, he also explains the specialized troubleshooting methods used which turn out not to be all that different from troubleshooting an automotive vacuum leak- only in this case, several magnitudes more complex and elemental in nature.

We also enjoyed the comments section, where [AlphaPhoenix] addresses some of the most common questions surrounding the video: Torque patterns, the scarcity of the gasses used, and leaving well enough alone.

Does talking about vacuums get you pumped? Perhaps you’d enjoy such vacuum hacks as putting the toothpaste back in the tube in your homemade vacuum chamber.

Thank you [Morgan] for sending this one in. Be sure to send in your own hacks, projects, and fantastic finds through the Tip Line!

Continue reading “Solving Ultra High Vacuum Leaks Has An Elementary Solution” →

Review: Mini AMG8833 Thermal Camera

August 12, 2021 by 29 Comments

In our ceaseless quest to bring you the best from the cheaper end of the global electronics markets, there are sometimes gadgets that we keep an eye on for a while because when they appear they’re just a little bit too pricey to consider cheap.

Today’s subject is just such a device, it’s a minimalist infra-red camera using the 8 pixel by 8 pixel Panasonic AMG8833 thermal sensor. This part has been around for a while, but even though any camera using it has orders of magnitude less performance than more accomplished models it has remained a little too expensive for a casual purchase. Indeed, these mini cameras were somewhere above £50 ($70) when they first came to our attention, but have now dropped to the point at which they can be found for somewhere over £30 ($42). Thirty quid is cheap enough for a punt on a thermal camera, so off went the order to China and the expected grey parcel duly arrived.

The interface on this camera is about as simple as it gets.
The interface on this camera is about as simple as it gets.

It’s a little unit, 40 mm x 35 mm x 18 mm, constructed of two laser-cut pieces of black plastic held together by brass stand-offs that hold a PCB between them, and on the front is a cut-out for the sensor while on the rear is one for the 35mm OLED display.At the side on the PCB is a micro USB socket which serves only as a power supply. It’s fair to say that this is a tiny unit.

Applying power from a USB battery bank, the screen comes up with a square colour thermal picture and a colour to temperature calibration stripe to its left. The colours adapt to the range of temperatures visible to the sensor, and there is a crosshair in the centre of the picture for which the temperature in Celsius is displayed below the picture. It’s a very straightforward and intuitive interface that requires no instruction, which is handy because the device has none. Continue reading “Review: Mini AMG8833 Thermal Camera” →

Should You Be Able To Repair It? We Think So.

August 11, 2021 by 179 Comments

You own it, you should be able to fix it. So much equipment on sale today has either been designed to be impossible to maintain, unnecessarily too complex to maintain, maintainable only with specialist tooling only available to authorised service agents, or with no repair parts availability. It’s a hot-button issue in an age when sustainability is a global concern, so legislators and regulators worldwide now finally have it in their sights after years of inaction and it’s become a buzzword. But what exactly is the right to repair, and what do we want it to be?

Is It Designed For Repair?

A Nestle Dolce Gusto machine
For some reason, pod coffee makers are especially resistant to repair. Andy1982, CC BY 3.0

The first question to consider is this: does it matter whether or not you have the right to repair something, if it’s designed specifically with lack of repairability in mind? Consider a typical domestic pod coffeemaker such as a Tassimo or similar: despite being physically quite a simple device, it is designed to be especially complex to dismantle and reassemble. You just can’t get into it when something goes wrong.

Should it be the preserve of regulators to require design for easy repair? We think so. There are other forces working on the designers of home appliances; design-for-manufacture considerations and exterior appearance concerns directly affect the firm’s bottom line, while the end users’ repair experience is often at the bottom of the list, even though the benefit at a national level is obvious. That’s what laws are for.
Continue reading “Should You Be Able To Repair It? We Think So.” →

A New Flying Car Illustrates The Same Old Problems

August 9, 2021 by 98 Comments

For almost as long as there have been cars and planes, people have speculated that one day we will all get around in flying cars. They’d allow us to “avoid the traffic” by flying through the air instead of sitting in snarling traffic jams on the ground.

The Klein Vision AirCar hopes to be just such a panacea to our modern traffic woes, serving as a transformable flying car that can both soar through the air and drive on the ground. Let’s take a look at the prototype vehicle’s achievements, and the inherent problems with the underlying flying car concept.

It Flies and Drives

The AirCar is a somewhat futuristic looking, yet simultaneously dated, vehicle. It’s a two-seater with a big bubble canopy for the driver and a single passenger. At the rear, there’s a propeller and twin-boom tail, while the folding wings tuck along either side of the vehicle in “car” mode. At the flick of a switch, the wings fold out and lock in place, while the tail extends further out to the rear. The conversion from driving mode to flight mode takes on the order of a few minutes. The powerplant at the heart of the vehicle is a 160-horsepower BMW engine which switches between driving the wheels and the propeller as needed.

Unlike some concepts we’ve explored in the past, the AirCar has successfully demonstrated itself as a working flying car without incident. Additionally, it did so as a single vehicular package, without removable wings or other such contrivances. On June 28th, 2021, it successfully flew from an airport in Nitra, Slovakia, down to the neighbouring city of Bratislava in 35 minutes – roughly half the time it takes by car. Company founder Stefan Klein was behind the controls, casually driving the vehicle downtown after the successful landing. Continue reading “A New Flying Car Illustrates The Same Old Problems” →