JWST mirror actuator model

Working Model Reveals Amazing Engineering Of Webb’s Mirror Actuators

We end up covering a lot of space topics here on Hackaday, not because we’re huge space nerds — spoiler alert: we are — but because when you’ve got an effectively unlimited budget and a remit to make something that cannot fail, awe-inspiring engineering is often the result. The mirror actuators on the James Webb Space Telescope are a perfect example of this extreme engineering, and to understand how they work a little better, [Zachary Tong] built a working model of these amazing machines.

The main mirror of the JWST is made of 18 separate hexagonal sections, the position of each which must be finely tuned to make a perfect reflector. Each mirror has seven actuators that move it through seven degrees of freedom — the usual six that a Stewart platform mechanism provides, plus the ability to deform the mirror’s curvature slightly. [Zach]’s model actuator is reverse-engineered from public information (PDF) made available by the mirror contractor, Ball Aerospace. While the OEM part is made from the usual space-rated alloys and materials, the model is 3D printed and powered by a cheap stepper motor.

That simplicity belies the ingenious mechanism revealed by the model. The actuators allow for both coarse and fine adjustments over a wide range of travel. A clever tumbler mechanism means that only one motor is needed for both fine and coarse adjustments, and a flexure mechanism is used to make the fine adjustments even finer — a step size of only 8 nanometers!

Hats off to [Zach] for digging into this for us, and for making all his files available in case you want to print your own. You may not be building a space observatory anytime soon, but there’s plenty about these mechanisms that can inform your designs.

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Hackaday Links: January 30, 2022

After all the fuss and bother along the way, it seems a bit anticlimactic now that the James Webb Space Telescope has arrived at its forever home orbiting around L2. The observatory finished its trip on schedule, arriving on January 24 in its fully deployed state, after a one-month journey and a couple of hundred single-point failure deployments. The next phase of the mission is commissioning, and is a somewhat more sedate and far less perilous process of tweaking and trimming the optical systems, and getting the telescope and its sensors down to operating temperature. The commissioning phase will take five or six months, so don’t count on any new desktop photos until summer at the earliest. Until then, enjoy the video below which answers some of the questions we had about what Webb can actually see — here’s hoping there’s not much interesting to see approximately in the plane of the ecliptic.

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Hackaday Links: January 16, 2022

As winter well and truly grips the northern hemisphere, it’s time once again to dunk on Tesla for leaving some owners out in the cold — literally. It seems that some Model 3 and Model Y owners are finding their ride’s heat pump isn’t exactly up to the task of, you know, pumping heat. That this seems to be happening mostly in the northeastern US and southern Canada, where a polar vortex is once again dominating the weather and driving temperatures down into the -30 °C (-22 °F) range, perhaps speaks more to the laws of thermodynamics than it does to the engineering of the Tesla climate control system. After all, if there’s not much heat outside the car, it’s hard to pump it inside. But then again, these are expensive machines, some of which have had extensive repairs to address this exact same issue when it cropped up last year. It seems to us that owners have a legitimate gripe with Tesla about this, and they may be getting some help from the Feds, who are taking an interest in the situation from a safety standpoint. After all, no heat likely means fogged up windows, and that’s hardly conducive to a safe trip. But hey, that’s what self-driving is for, right?

Much has been made of the dearth of engineering cameras on the James Webb Space Telescope, and the fact that we’ve been relying on animations to illustrate the dozens of deployments needed to unfurl the observatory and make it ready for its mission. Putting aside the fact that adding extra cameras to the spacecraft makes little sense since the interesting stuff was all happening on the side where the sun doesn’t shine, we did get treated to what was billed as “humanity’s last look at Webb” thanks to an engineering camera on the Ariane 5 rocket. But not so fast — an astrophotographer named Ethan Gone managed to spot the JWST as it transited to L2 the day after launch. Granted, the blip of light isn’t as spectacular as the Ariane shots, and it took a heck of a lot of astrophotography gear to do it, but it’s still thrilling to watch Webb moving gracefully through Orion.

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Hackaday Links: January 9, 2022

It looks like we have a new space observatory! According to NASA, all the major deployments on the James Webb Space Telescope have been completed successfully. This includes the tricky sunshield deployment and tensioning, which went off this week without much in the way of trouble. The final major deployment, the unfolding of the starboard wing of the primary mirror of the telescope, was completed on Saturday while the spacecraft was still almost 400,000 km from its forever home orbiting Lagrange point L2. Mission controllers had allotted two weeks for the 300-odd deployments needed to turn the packaged machine into a working observatory. The remaining two weeks or so of flight include less dramatic tasks, such as trimming the shape of the primary mirror with servos that subtly alter the position and curvature of each of the 18 segments, plus a bunch of calibration tasks. But it looks like most of the really scary stuff is behind us now.

From the “Interesting Innards” department, if you’re a fan of either gaming or industrial CT scans, check out Scan of the Month’s look inside Nintendo handheld game consoles. They’ve put a bunch of games through computed tomography scans, and the results are really interesting, false-colored though they may be. Seeing the progression of technology from the original 1989 Game Boy to the Switch is fascinating. The side notes on the history and tech inside each one are pretty cool too.

A couple of weeks ago we mentioned Andrew Sink’s online low-poly generator, which takes any 3D model and allows you to control the number of polygons used to render it. He dropped us a line to let us know the tool proved popular enough that he had to move it off GitHub and onto a dedicated site. Check it out at its new home.

When something like this pops up in your feed, it seems like the best approach is to share it. It’s called DentalSlim, and claims to be the first intra-oral device designed for weight loss. It’s a hardware lock for your teeth, and it looks perfectly horrifying. The device is designed to be applied by a sadist dentist and effectively locks the lower jaw to the upper with magnets, allowing the wearer to open his or her mouth only enough to take a liquid diet. There’s also a provision for the wearer to unlock the device in an emergency, which is wise — can you imagine catching a stomach bug with your jaw locked shut? — but that seems to defeat the “hardware-enforced willpower” that the device is based on.

Have you got a bunch of filament spools lying around from all that 3D printing? Rather than put them to use rolling up strings of lights from the Christmas tree, here’s another idea: turn them into nice covered bird feeders. All you need to do is apply a rim around one side to hold the seed before hanging them out for the birds. We suppose walling off the space between the sides completely and drilling some holes could also turn them into birdhouses, too.

And finally, if your filament spool bird feeder isn’t attracting the attention of the neighborhood cats, perhaps it’s because they’ve found a nice, cozy spot to soak up some heat. At least that’s what some Starlink users are seeing as their feline friends cuddle up on Dishy McFlatface for a long winter’s nap. You see, the phased array antenna inside the enclosure gets pretty toasty, and cats are pretty much any-port-in-a-storm critters, so it’s only natural. We can’t imagine their choice of basking locale does much for data throughput, and it’s probably quite a laugh when the dish pivots to track a satellite. But it’s hard to feel sorry for something that sleeps 23-½ hours a day.

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Hackaday Links: January 2, 2022

That sound you may have heard in the wee hours of Christmas morning had nothing to do with Santa; rather, it was the sound of a million astronomers collectively letting out their breath around the world as the James Webb Space Telescope survived its fiery ride to space. And not only did it survive, but the ESA launch team did such a good job putting the Ariane rocket on course that NASA predicts the observatory now has enough fuel to more than double its planned ten-year mission. Everything about the deployment process seems to be going well, too, with all the operations — including the critical unfurling of the massive and delicate sunshield — coming off without a hitch. Next up: tensioning of the multiple layers of the sunshield. If you want to play along at home, NASA has a nice site set up to track where JWST is and what its current status is, including temperatures at various points on the telescope.

We got a tip from Mark about some dodgy jumper wires that we thought we should share. Low-quality jumpers aren’t really a new problem, but they can really put a damper on the fun of prototyping. The ones that Mark found could be downright dangerous. He got them with a recent dev board purchase; outwardly, they appear fine, at least at first. Upon closer inspection, though, the conductors have turned to powder inside the insulation. Even the insulation is awful, since it discolors when even slightly flexed. He suspects conductors are actually copper-plated aluminum; check out his pictures below and maybe look through your collection for similarly afflicted jumpers.

Speaking of dodgy hardware, if you love the smell of melting MOSFETs in the morning, then have we got a deal for you. It seems that a non-zero number of Asus Z690 Hero PC motherboards have suffered a fiery demise lately, stirring complaints and discontent. This led some curious types to look for the root cause, which led to the theory that an electrolytic cap had been installed with the wrong polarity on the dead boards. Asus confirmed the diagnosis, and is doing the right thing as they are “working with the relevant government agencies on a replacement program.” So if you’ve got one of these motherboards, you might want to watch the video below and see how the caps were installed.

If you’re in the mood for some engineering eye-candy, check out the latest video from Asianometry. They’ve got a finger on the pulse of the semiconductor industry, with particular attention paid to the engineering involved in making the chips we all have come to depend on. The video below goes into detail on the extreme ultraviolet (EUV) light source that fabrication machine maker ASML is developing for the next generation of chip making. The goal is to produce light with a mind-bending wavelength of only 13.5 nanometers. We won’t spoil the details, but suffice it to say that hitting microscopic droplets of tin with not one but two lasers is a bit of a challenge.

And finally, bad luck for 38 people in Tokyo who were part of a data breach by the city’s Metropolitan Police Department. Or rather, good luck since the data breach was caused by the loss of two floppy disks containing their information. The police say that there haven’t been any reports of misuse of the data yet, which is really not surprising since PCs with floppy drives are a little thin on the ground these days. You’d think that this would mean the floppies were left over from the 90s or early 2000s, but no — the police say they received the disks in December of 2019 and February of 2021. We’d love to know why they’re still using floppies for something like this, although it probably boils down to yet another case of “if it ain’t broke, don’t fix it.”

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Hackaday Links: December 26, 2021

At the time of this writing, the James Webb Space Telescope was perched upon its ride to space, ready for its much-delayed launch from the ESA spaceport in French Guiana. The $10 billion space observatory suffered one final delay (knocks on wood) when predictions of high winds aloft pushed it back from a Christmas Eve launch to a Christmas Day departure, at 12:20 UTC. Given the exigencies of the day, we doubt we’ll be able to watch the launch live — then again, past experience indicates we’ll still be wrapping presents at 4:20 PST. Either way, here’s hoping that everything comes off without a hitch, and that astronomers get the present they’ve been waiting many, many Christmases for.

In other space news, things are getting really interesting on Mars. The ESA announced that their ExoMars Trace Gas Orbiter has detected signs of water in the Valles Marineris. The satellite found a large area of increased hydrogen concentration in the top meter of Martian soil; the assumption is that the hydrogen comes from water, meaning that as much as 40% of the material in the region scanned may be water. If so, that’s a huge find, as we thought most of Mars’ water was locked in the polar regions. The Mariner Valley stretches more than 4,000 km just below the equator, and so may prove to be an important resource for future explorers.

Meanwhile, in Jezero crater, Perseverance has decided to upstage its rotorcraft sidekick for a change by finding signs of organic molecules on Mars. It’s not the first time organic compounds have been found — Perseverance’s cousin Curiosity found some too, ESA’s Mars Express mission spotted methane from on high, and then there were the equivocal but intriguing results from the Viking missions in the 1970s. But the latest evidence is really great news for the scientists who picked Jezero crater as a likely place to search for signs of past life on Mars. The organics found are not proof of life by any means, as there are many ways to make organic molecules abiotically. But then again, if you’re going to find evidence of life on Mars, you’ve got to start with detecting organics.

Back on Earth, getting your laptop stolen would be bad enough. But what if it got yoinked while it was unlocked? Depending on who you are and what you do with that machine, it could be a death sentence. That’s where BusKill could come in handy. It’s a hardware-software approach to securing a laptop when it — or you — suddenly goes missing. A dongle with a breakaway magnetic lanyard gets plugged into a USB port, and the other end of the lanyard gets attached to your person. If you get separated from your machine, the dongle sends customizable commands to either lock the screen or, for the sufficiently paranoid, nuke the hard drive. The designs are all up on GitHub, so check it out and think about what else this could be useful for.

If you like the look of low-poly models but hate the work involved in making them, our friend and Hack Chat alumnus Andrew Sink came up with a solution: an online 3D low-poly generator. The tool is pretty neat; it uses three.js and runs completely in-browser. All you have to do is upload an STL file and set sliders to get rid of as many triangles as you want. Great stuff, and fun to play with even if you don’t need to decimate your polygons.

And finally, what have you done with your oscilloscope for the last three years? Most of us can’t answer that except in the vaguest of terms, but then there’s DrTune, who took three years’ worth of screencaps from this Rigol DS1054z and strung them together into a 60-second movie. He swears he didn’t purposely sync the video to the soundtrack, which is “Flight of the Bumblebee” by Rimsky-Korsakov, but in some places it’s just perfect. See if you can guess what DrTune has been working on by watching the waveforms fly by. And watch for Easter eggs.

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Hackaday Links: December 19, 2021

Key fobs as a service? Have we really gotten to that point? It would seem so, at least for Toyota, which is now requiring a subscription to use the company’s Remote Connect function. To be fair to Toyota, the Remote Connect system seems to do a bit more than the average key fob, with things like remote start and smartphone or smartwatch integration. It doesn’t appear that using the key fob for more mundane uses, like opening the doors, will be nerfed by this change. But if you want to warm up your car on a cold winter’s morn while you’re still in your jammies, then be prepared to cough up $8 a month or $80 a year on select 2018 and above models. Whether Toyota and other manufacturers get away with this nickel-and-dime stuff is up to the buyers, of course; if enough people opt out, maybe they’ll think of some other way to pad their bottom line. But since we’ve already seen heated seats as a service (last item), we suspect this is the shape of things to come, and that it will spread well beyond the car industry.

Speaking of cars, if you thought the chip shortage was over just because car dealer lots are filling back up, think again. Steve over at Big Mess o’ Wires reports that he’s having trouble sourcing chips for his vintage computer accessories. He includes a screenshot from Digi-Key showing zero stock on ATmega1284s. He also reports that the Lattice FPGA he uses for his Yellowstone universal disc controller is now unobtainium, where it had previously been easily sourced for about $5. He also has a pointed warning about some suppliers making it look like they have stock, only to send a “whoopsie” email after charging your credit card, or worse, telling you the price has increased over 400%. We suppose this was inevitable; there’s only so much fab capacity in the world, so eventually the fabs will switch over to producing whatever they can get paid the most for. And since car manufacturers have a lot more clout with suppliers than just about anyone else, it’s only natural for the shortages to shift down-market like this.

Do we finally have a “go” on James Webb? Maybe. The launch of the space telescope was originally scheduled for December 18 — well, OK, originally it was supposed to be in space in 2007, but let’s not go there — but a problem with a clamp caused unexpected vibrations in the $10 billion space observatory, resulting in inspections that pushed the launch back to the 22nd. That lasted for about a week, until the fueled and packaged spacecraft stopped sending data to launch controllers. The problem ended up being entirely relatable — a bad data cable — but resulted in the loss of two more days. JWST is now set to launch on Christmas Eve at 7:20 AM Eastern Standard Time, pending a readiness review on Tuesday morning. Fingers crossed that the long-awaited observatory has a safe 30-day trip to Lagrange point L2.

And finally, breathless tech journalists couldn’t wait to report this week that the world’s first warp bubble had been created. The paper was published by Dr. Harold “Sonny” White et al from the Limitless Space Institute, and claims to have discovered a “micro/nano-scale structure” that “predicts negative energy density distribution that closely matches requirements for the Alcubierre metric.” That last bit, the one about the Alcubierre metric, refers to the Alcubierre drive, which proposed a way to warp space-time and drive a ship at arbitrarily high speeds. But did this team actually create a warp bubble? It doesn’t seem so, at least according to one article we read. There’s also the problem of Dr. White’s previous claims of breaking the laws of physics with a reactionless EM drive. Scientific quibbling aside, there’s a sure-fire way of telling that no warp bubble was created — if there had been one, this would have happened.