How Different Are SpaceX Thermal Tiles From The Space Shuttle’s?

February 14, 2024 by Maya Posch 9 Comments

When SpaceX first showed off the thermal tiles on its Starship spacecraft that should keep it safe when re-entering the Earth’s atmosphere towards the loving embrace of the chopsticks on the launch tower, some similarity to the thermal tiles on NASA’s now retired Space Shuttle Orbiter was hard to miss.

Electron microscope image of the fibrous part of a Starship thermal tile, showing very large fibers. (Credit: Breaking Taps, YouTube)

Yet how similar are they really? That’s what the [Breaking Taps] channel on YouTube sought to find out, using an eBay-purchased chunk of Shuttle thermal tile along with bits of Starship tiles that washed ashore following the explosive end to the vehicle’s first integrated test last year.

To answer the basic question: the SpaceX engineers responsible for the Starship thermal tiles seem to have done their homework. An analysis of not only the structure of the fibrous material, but also the black IR-blocking coating, shows that the Starship tiles are highly reminiscent of the EATB (introduced in 1996) tiles with TUFI (toughened unipiece fibrous insulation) coatings with added molybdenum disilicide, which were used during the last years of the Shuttle program.

TUFI is less fragile than the older RCG (reaction cured glass) coating, but also heavier, which is why few TUFI tiles were used on the Shuttles due to weight concerns. An oddity with the Starship tiles is that they incorporate many very large fibers, which could be by design, or indicative of something else.

Continue reading “How Different Are SpaceX Thermal Tiles From The Space Shuttle’s?” →

Inputs Of Interest: The Svalboard Could Be Your Salvation

February 14, 2024 by Kristina Panos 12 Comments

You know, sometimes dreams really do come true. When I told you about the DataHand keyboard almost four years ago, I never imagined I’d ever get to lay my hands on anything even remotely like it, between the original price point and the fact that they really, really hold their value. But thanks to [Morgan Venable], creator of the Svalboard, I can finally tell you what it’s like to type with your digits directionalized.

If you don’t recall, the DataHand was touted to be a total revolution in typing for RSI sufferers. It debuted in 1993 for a hefty price tag of about $1,500 — pretty far out of reach of the average consumer, but well within the budgets of the IT departments of companies who really wanted to keep their workers working. You want minimum finger travel? It doesn’t get more minimal than this concept of a d-pad plus the regular down action for each finger.

The Svalboard aims to be the new and improved solution for something that barely exists anymore, but still has a devoted following. Although the DataHand was built on a gantry and adjustable using knobs, the smallest fit possible on the thing is still rather big. Conversely, the Svalboard is fully customizable to suit any size hand and fingertip.

Continue reading “Inputs Of Interest: The Svalboard Could Be Your Salvation” →

How Many Time Zones Are There Anyway?

February 14, 2024 by Al Williams 38 Comments

Nowadays, it’s an even bet that your newest project somehow connects to the Internet and, thus, to the world. Even if it doesn’t, if you share your plans, someone might reproduce your creation in some far distant locale. If your design uses time, you might need to think about time zones. Easy, right? That’s what [Zain Rizvi] thought until he tried to deploy something that converted between timezones. You can learn from his misconceptions thanks to a detailed post he provides.

You might think, “What’s the big deal?” After all, there’s UTC, and then there are 12 time zones ahead of UTC and 12 time zones later. But that’s not even close to true.

As [Zain] found out, there are 27 hours in a full-day cycle if you count UTC as one hour. Why? Because some islands in the Pacific wanted to be on the wrong side of the International Date Line. So there are a few extra zones to accommodate them.

You can’t even count on time zones being offset by an hour from the previous zone. Several zones have a half-hour offset from UTC (for example, India’s standard time is 5.5 hours from UTC). But surely the offset is always either a whole number or a number where the fractional part is 0.5, right?

Um, no. Nepal wants the sun to be directly over the mountain at noon, so it offsets by 45 minutes! [Zain] wonders — as we do — what would happen if the mountain shifted over time? Until 1940, Amsterdam used a 20-minute offset. Some cities are split with one half in one time zone and another in the other.

Of course, there are the usual problems with multiple names for each zone, both because many countries want their own zone and because the exact same zone is different in different languages. Having your own zone is not just for vanity, though. Daylight savings time rules will vary by zone and even, in some cases, only in certain parts of a zone. For example, in the United States, Arizona doesn’t change to daylight savings time. Oh, except for the Navajo Nation in Arizona, which does! Some areas observe daylight savings time that starts and ends multiple times during the year. Even if you observe daylight savings time, there are cases where the time shift isn’t an entire hour.

Besides multiple names, common names for zones often overlap. For example, in the United States, the Eastern Standard Time zone differs from Australia’s. Confused? You should be.

Maybe we should have more respect for multiple time zone clock projects. We’ve noticed these problems before when we felt sorry for the people who maintain the official time zone database.

Parts We Miss: The Mains Transformer

February 14, 2024 by Jenny List 57 Comments

About two decades ago there was a quiet revolution in electronics which went unnoticed by many, but which overturned a hundred years of accepted practice. You’d have noticed it if you had a mobile phone, the charger for your Nokia dumbphone around the year 2000 would have been a weighty device, while the one for your feature phone five years later would have been about the same size but relatively light as a feather. The electronics industry abandoned the mains transformer from their wall wart power supplies and other places in favour of the much lighter and efficient switch mode power supply. Small mains transformers which had been ubiquitous in electronics projects for many years, slowly followed suit.

Coils Of Wire, Doing Magic With Electrons

Inside and outside views of Jenny Lists's home made linear power supply from about 1990 — This was a state of the art project for a future Hackaday scribe back in 1990.

A transformer works through transferring alternating electrical current into magnetic flux by means of a coil of wire, and then converting the flux back to electric current in a second coil. The flux is channeled through a ferromagnetic transformer core made of iron in the case of a mains transformer, and the ratio of input voltage to output voltage is the same as the turns ratio between the two. They provide a safe isolation between their two sides, and in the case of a mains transformer they often have a voltage regulating function as their core material is selected to saturate should the input voltage become too high. The efficiency of a transformer depends on a range of factors including its core material and the frequency of operation, with transformer size decreasing with frequency as efficiency increases.

When energy efficiency rules were introduced over recent decades they would signal the demise of the mains transformer, as the greater efficiency of a switch-mode supply became the easiest way to achieve the energy savings. In a sense the mains transformer never went away, as it morphed into the small ferrite-cored part running at a higher frequency in the switch-mode circuitry, but it’s fair to say that the iron-cored transformers of old are now a rare sight. Does this matter? It’s time to unpack some of the issues surrounding a small power supply. Continue reading “Parts We Miss: The Mains Transformer” →

Apple Pushes Back On Right To Repair Bill Due To Parts Pairing

February 14, 2024 by Maya Posch 66 Comments

After previously supporting one in California, Apple has made an about-face and is now pushing back against a “Right to Repair” bill (Senate Bill 1596) currently under consideration in Oregon. The reason for this appears to be due to this new bill making parts pairing illegal, as reported by [404media] and [PCMag].

The practice of parts pairing is becoming ever more prevalent with Apple devices, which links specific parts of a system such as cameras, displays, batteries, and fingerprint sensors to the mainboard. During the open hearing on the newly proposed Oregonian bill, Apple’s [John Perry] insisted that this parts pairing is done for user security, safety and privacy.

Even in we take that claim at face value, the fact remains that with parts pairing in place, only authorized Apple repair centers can routinely replace components — while user repairs are limited to specific devices with limited part availability. Even in the latter case the user still has to contact Apple to have them reauthorize the replaced part. This is becoming an issue with Apple’s MacBooks as well, where the lid angle sensor requires calibration using a proprietary tool.

During the same hearing, the director of an Oregon nonprofit organization noted that of the 15,000 iPhones which they had donated to them last year, only 300 could be refurbished due to parts pairing. The remainder of otherwise perfectly fine phones are discarded for recycling, which is terrible for everyone but Apple. Whether the parts pairing element of the bill survives it to the final form remains to be seen, but if it passes it’d set the trend for future bills in other states as well as amendments to existing ones.

Thanks to [paulvdh] for the tip.

AI-Powered Bumper Sticker Provides Context-Sensitive Urban Camouflage

February 14, 2024 by Dan Maloney 17 Comments

While we absolutely support the right of everyone to express their opinions, it seems to us that it’s rarely wise to turn your vehicle into a mobile billboard for your positions. Aside from potentially messing up the finish on your car, what’s popular and acceptable at home might attract unwanted attention while traveling abroad, leading to confrontations that might make your trip a little more eventful than it needs to be.

So why not let technology help you speak your mind in a locally sensitive manner? That’s the idea behind [Pegor]’s “smahtSticker”, an AI-powered bumper sticker that provides the ultimate in context-sensitive urban camouflage. The business end of smahtSticker — we’re going to go out on a limb here and predict that [Pegor] hails from the Boston area — is an 8.8″ (22-cm) wide HDMI display capable of 1920×480 resolution. That goes on the back of your car and is driven by a Raspberry Pi Zero with a GPS module. The Pi grabs a geolocation every second, and if you’ve moved more than 25 feet (7.6 m) — political divisions are at least that granular in the US right now, trust us — it grabs your current ZIP code using GeoPy. That initiates a query to the OpenAI API to determine the current political attitudes in your location, which is used to select the right slogan to display. You’ll fit in no matter where you wander — wicked smaht!

Now, of course, this is all in good fun, and with tongue planted firmly in cheek. The display isn’t weatherized at all, so that would need to be addressed if one felt like fielding this. Also, ZIP codes may be good for a lot of things, but it’s not the best proxy for political alignment, so you might want to touch that part up.

Thermal Earring Tracks Body Temperature

February 13, 2024 by Kristina Panos 11 Comments

If you want to constantly measure body temperature to track things like ovulation, you usually have to wear something around your wrist or finger in the form of a smartwatch or ring. Well, what if you can’t or don’t want to adorn yourself this way? Then there’s the thermal earring.

Developed at the University of Washington, the thermal earring is quite small and unobtrusive compared to a smartwatch. Sure, it dangles, but that’s so it can measure ambient temperature for comparison’s sake.

You don’t even need to have pierced ears — the earring attaches to the lobe magnetically. And yeah, the earring can be decorated to hide the circuitry, but you know we would rock the bare boards.

The earring uses BLE to transmit readings throughout the day, and of course goes into sleep mode between transmissions to save power. Coincidentally, it runs for 28 days per charge, which is the length of the average menstrual cycle. While the earring at this time merely “shows promise” as a means of monitoring stress and ovulation, it did outperform a smartwatch at measuring skin temperature while the wearers were at rest.

This is definitely not the only pair of earrings we’ve got around here. These art deco earrings use flexible PCBs, and this pair will light up the night.