The basic principles of a motion picture film camera should be well understood by most readers — after all, it’s been well over a hundred years since the Lumière brothers wowed 19th century Paris with their first films. But making one yourself is another matter entirely, as they are surprisingly complex and high-precision devices. This hasn’t stopped [Henry Kidman] from giving it a go though, and what makes his camera more remarkable is that it’s 3D printed.
The problem facing a 16mm movie camera designer lies in precisely advancing the film by one frame at the correct rate while filming, something done in the past with a small metal claw that grabs each successive sprocket. His design eschews that for a sprocket driven by a stepper motor from an Arduino. His rotary shutter is driven by another stepper motor, and he has the basis of a good camera.
The tests show promise, but he encounters a stability problem, because as it turns out, it’s difficult to print a 16mm sprocket in plastic without it warping. He solves this by aligning frames in post-processing. After fixing a range of small problems though, he has a camera that delivers a very good picture quality, and that makes us envious.
The build is based around a Raspberry Pi Compute Module 4. If you’re unfamiliar with the Compute Module, it’s basically a Raspberry Pi that has been designed specifically for easy integration into a larger carrier PCB. In this case, the carrier PCB interfaces all the other necessary gear to make this a fully functional computer. The PCB is installed inside a vaguely-rectangular 3D-printed enclosure, with a 5-inch TFT LCD on a sliding mount. Push the screen up, and it reveals a small-format keyboard for text entry. There’s also a hall-effect joystick and a couple of buttons for mouse control to boot. [Rahmanshaber] has designed the computer to run off a couple of different battery packs—you can use a pair of 18650 cells if you like, or switch to lager 21700 cells if you want greater capacity for longer running time.
You’ve got a laser cutter. You’ve got a 3D printer. What do you make? [Ayushmaan45] suggests a telescope. The modest instrument isn’t going to do serious astronomy with only 8X worth of optics, but it would make a fine spyglass for a youngster.
The body is cut from MDF, and there are only a few 3D printed parts. The only other things you need are rubber bands and a pair of lenses. You don’t even need glue. We might have spray painted the inside of the scope black or used some black contact paper to cut down on reflections, although it probably wouldn’t make much difference.
Of course, depending on your lenses, you may have to make some changes. Or find new lenses, for that matter. We like that it doesn’t take any exotic parts. We also appreciate that it is easy for kids to take apart and put back together. It would be interesting to see how a motivated kid might alter the design, as well.
Arguably, the golden age of browser gaming occurred in the 00s mostly revolving around Adobe Flash. This was an era with high creativity and a low barrier of entry, and also decentralized from gatekeeping app stores. Sadly, these times have passed us by as the security concerns around Flash led to its discontinuation and most casual gamers have migrated to the app store for their fix. But that doesn’t stop some from continuing to bring gaming to the browser, even if those games were never intended for it in the first place like this browser port of Celeste.
Celeste is an indie platformer where the player climbs a mysterious mountain while confronting her inner struggles. Originally meant for consoles and PC, a group of friends including [velzie], [bomberfish], and [Toshit] aka [r58Playz] took this as a challenge especially after seeing someone else’s half finished web port of this game. Most of the build revolves around WebAssembly (wasm) and around “cursed” .NET runtime hacks which also allow the port to run the community-made Everest mod loader. It uses a multithreaded and JIT compiling version of mono-wasm backported from .NET 10 to .NET 9 to maximize performance. The team actually first started by porting Terraria to the browser, and then moved on to this Celeste port from there.
The port of Celeste can be played here, and their port of Terrariais also available, although may not support a ton of Hackaday traffic so some patience is advised. There are also GitHub repositories for Celeste and Terraria as well. With impressive ports of relatively modern games moving into the browser, perhaps we’re entering a new golden age of browser gaming; we’ve also seen things like Minecraft implemented in only HTML and CSS lately as well.
Aliens is the second film from the legendary science-fiction series about, well… aliens. Naturally, it featured some compelling future-tech — such as the M314 Motion Tracker. [RobSmithDev] wanted to recreate the device himself, using modern technology to replicate the functionality as closely as possible.
While a lot of cosmetic replicas exist in the world, [Rob] wanted to make the thing work for real. To that end, he grabbed the DreamHAT+ Radar HAT for the Raspberry Pi. It’s a short-range radar module, and thus is useless for equipping your own air force or building surface-to-air weaponry. However, it can detect motion in a range of a few meters or so, using its 60 GHz transmitter and three receivers all baked into the one chip.
[Rob] does a great job of explaining how the radar works, and how he integrated it into a viable handheld motion tracker that works very similarly to the one in the movie. It may not exactly keep you safe from alien predators, but it’s always fun to see a functional prop rather than one that just looks good.
This isn’t the first time we’ve seen somebody try to replicate this particular prop, but the modern electronics used in this build definitely bring it to the next level.
The Las Vegas Sphere is great and all, but few of us can afford the expense to travel to out there to see it on the regular. If you’re looking for similar vibes you can access at home, you might enjoy the desk toy that [AGBarber] has designed.
The scale is small — the sphere measures just 98 mm (3.6 inches) in diameter — but that just means it’s accessible enough to be fun. The build is based around various sizes of WS2812B addressable LED rings, and contains 120 individual RGB LEDs in total. They’re wrapped up in a 3D printed housing which does a great job of diffusing the light. Transparent filament was used to print parts that light up with a richly-saturated glow with few visible hotspots. Commanding the LEDs is an ESP8266 microcontroller in the form of a Wemos D1 Mini, which provides plenty of grunt to run animations as well as great wireless connectivity options. [AGBarber] relied on their own Pixel Spork library to handle all the cool lighting effects. Files are on GitHub for the curious.
Maybe you don’t like spheres, and icosahedrons are more your speed. Well, we’ve featured those too—with 2,400 LEDs, no less.
These days, surveillance cameras are all around us, and they’re smarter than ever. In particular, many of them are running advanced algorithms to recognize faces and scan license plates, compiling ever-greater databases on the movements and lives of individuals. Flock You is a project that aims to, at the very least, catalogue this part of the surveillance state, by detecting these cameras out in the wild.
The system is most specifically set up to detect surveillance cameras from Flock Safety, though it’s worth noting a wide range of companies produce plate-reading cameras and associated surveillance systems these days. The device uses an ESP32 microcontroller to detect these devices, relying on the in-built wireless hardware to do the job. The project can be built on a Oui-Spy device from Colonel Panic, or just by using a standard Xiao ESP32 S3 if so desired. By looking at Wi-Fi probe requests and beacon frames, as well as Bluetooth advertisements, it’s possible for the device to pick up telltale transmissions from a range of these cameras, with various pattern-matching techniques and MAC addresses used to filter results in this regard. When the device finds a camera, it sounds a buzzer notifying the user of this fact.
Meanwhile, if you’re interested in just how prevalent plate-reading cameras really are, you might also find deflock.me interesting. It’s a map of ALPR camera locations all over the world, and you can submit your own findings if so desired. The techniques used by in the Flock You project are based on learnings from the DeFlock project. Meanwhile, if you want to join the surveillance state on your own terms, you can always build your own license plate reader instead!
If we’re talking about oxidized iron… probably nobody. If we’re talking about Rust the programming language, well, that might be a different story. Google agrees, and is working on bringing the language into Android. That’s not enough for [Paul Sanja], who has the first Redox OS smartphone.
It’s alive!
Redox OS is a Unix-like operating system written entirely in Rust, and somehow we haven’t covered it until now. Unlike Asterinas, a project to recreate the Linux kernel in Rust, Redox has few pretensions of being anything but its own thing, and that’s great! On desktop, Redox has a working windowing system and many utilities, including a basic browser in the form of NetSurf.
It’s claims to be source-compatible with Linux and BSD programs, and partially POSIX compliant. A certain someone around here might want to try it as a daily driver. The header image is a desktop screenshot, because there’s more to see there and it fits our aspect ratio.
On smartphones, it… boots. Some smartphones, anyway. It’s actually a big first step. That booting is possible is actually thanks to the great work put in by the Postmarket OS team to get Uboot working on select android devices. That uboot loader doesn’t need to load the Linux-based Postmarket OS. It can be used for anything compatible. Like, say, Redox OS, as [Paul] shows us.
Of course, Redox OS has no drivers for the touchscreen or anything else, so at the moment that rusty smartphone can only boot to a login screen. But thanks to Rust, you can rest assured that login screen hasn’t got any memory leaks! Jokes aside, this is a great start and we’re hoping to see more.
Redox is a promising project on mobile or desktop, and its development seems a much better use of time and effort than fighting over Rust in the Linux kernel.
[Curious Scientist] has been working with some image sensors. The latest project around it is a 6K camera. Of course, the sensor gives you a lot of it, but it also requires some off-the-shelf parts and, of course, some 3D printed components.
An off-the-shelf part of a case provides a reliable C mount. There’s also an IR filter in a 3D-printed bracket.
The processor gets hot, so he used different heat sinks and a fan, too. Overall, this isn’t much custom electronics, but this is an excellent example of assembling existing parts with high-quality 3D printed components.
Heat-set inserts provide a tripod mount. There’s also a custom HDMI monitor mount if you don’t want to use your phone as a viewfinder. One neat oddity that helps is a USB-A cable that splits into three USB-C connectors. Of course, only one of them has data lines. The other two feed power to different parts of the camera.
A good-looking build. At a glance, you could easily think this was a commercial product. We do like these digital camera builds, but we also find 3D printed film cameras fascinating. If 6K is too much for you, you can always downsize.
Disposable batteries seem so 1990s. Sure, it’s nice to be able to spend a couple of bucks at the drugstore and get a flashlight or TV remote back in the game, but when the device is a daily driver, rechargeable batteries sure seem to make more financial sense. Unfortunately, what makes sense to the end user doesn’t always make sense to manufacturers, so rolling your own rechargeable calculator battery pack might be your best option.
This slick hack comes to us from [Magmabow], who uses a Casio FXCG50 calculator, a known battery hog. With regular use, it goes through a set of four alkaline AA batteries every couple of months, which adds up quickly. In search of a visually clean build, [Magmabow] based the build around the biggest LiPo pillow-pack he could find that would fit inside the empty battery compartment, and planned to tap into the calculator’s existing USB port for charging. A custom PCB provides charging control and boosts the nominal 3.7-volt output of the battery to the 5-ish volts the calculator wants to see. The PCB design is quite clever; it spans across the battery compartment, with its output feeding directly into the spring contacts normally used for the AAs. A 3D-printed insert keeps the LiPo and the PCB in place inside the battery compartment.
Almost no modifications to the calculator are needed, other than a couple of bodge wires to connect the battery pack to the calculator’s USB port. The downside is that the calculator’s battery status indicator won’t work anymore since the controller will just shut the 5-volt output down when the LiPo is discharged. It seems like there might be a simple fix for that, but implementing it on such a small PCB could be quite a challenge, in which case a calculator with a little more room to work with might be nice.
[Noisy Electrons] is a maker who also likes to keep fish. He sometimes needs to travel and keep his fish fed in the meantime, so he created an automated solution to handle that for him.
The build is based around an STM32 microcontroller, paired with a MCP7940N real-time clock to keep time. The microcontroller is hooked up to a few buttons and a small display to serve as an interface, allowing the feeding times and dosage amounts to be configured right on the device. Food is distributed from a 3D printed drum with a hole in it, which is rotated via a stepper motor. Each time the drum rotates, some food falls through the hole and into the tank. Dosage amount is measured in rotations — the more times the drum rotates, the more food is delivered to the fish.
[Noisy Electron] built three of these devices for three separate tanks. Thus far, it’s been three weeks and all the fish are still alive, so we’ll take that as a vote of confidence in the build. We’ve featured some other great pet feeders over the years, too
Fresh hacks here! Get your fresh hot hacks right here! Elliot and Dan teamed up this week to go through every story published on our pages to find the best of the best, the cream of the crop, and serve them up hot and fresh for you. The news this week was all from space, with the ISS getting its latest push from Dragon, plus <<checks notes>> oh yeah, life on Mars. Well, maybe, but it’s looking more and more like we are not alone, or at least not a few million years ago.
But even if we are, plenty is still going on down here to keep you interested. Like homebrewing? Good, because we looked at DIY inductors, wire nuts, and even a dope — but nope — ultralight helicopter. Into retro? We’ve got you covered with a loving look at IRC, a 60s bedside computer guaranteed to end your marriage, and a look at the best 8-bit language you never heard of.
We looked at a rescued fume hood, sensors galore on your phone, a rug that should have — and did, kind of — use a 555, and raytracing for the rest of your natural life. As for “Can’t Miss Articles,” Elliot could barely contain himself with the bounty of projects written up by our Hackaday writers, not to mention Arya’s deep dive into putting GPS modules to work in your builds.
Generally, you think that if you pay more for something, it must be better, right? But that’s not always true. Even if it is true at the lower end, sometimes premium brands are just barely better than the midrange. [Project Farm] looks at a bunch of different calipers — a constant fixture around the shop if you do any machining, 3D printing, or PCB layout. The price range spans from less than $10 for some Harbor Freight specials to brands like Mitutoyo, which cost well over $100. Where’s the sweet spot? See the video below to find out.
The first part of the video covers how much the units weigh, how smooth the action is, and how much force it takes to push it down. However, those are not what you probably care most about. The real questions are how accurate and repeatable they are.
If you just want a summary of the first part of the video, skip to the ten minute mark. The table there shows that the three instruments that have the most consistent force on the slide range in price from $27 to $72. The $454 pair (which, to be fair, included a micrometer) was number six by that measure. The smoothness factor, which is somewhat subjective, came in favor of the most expensive pair, but there was a $25 caliper that was nearly as good in the number two slot.
Using a calibration block and some special techniques, he attempts to see how accurate they all are. We wish he’d used millimeters instead of inches, but in the inch range, none of them are bad. Only one set had a real problem of not making consistent readings.
If you want to jump right to the tables again, jump to the 17:20 mark. With two exceptions, they were all mostly accurate and fell into three groups. We wondered if there are three different chipsets involved. The cheapest caliper in the first group cost $27 and was as good as the expensive Mitutoyo. The second group ranged from $18 to as much as $40 and were only 0.000675 inches (only 0.017145 mm) off from the higher group.
Which was the best? That table is at about the 18:00 minute mark. In all fairness, the best, by his estimation, did cost $144, so it was the second most expensive set in the review. But that’s still cheaper than the Mitutoyo, which placed third. The fourth-place set was good, too, and came in at $27. For a few bucks less, the sixth-place caliper was also good.
Do you know how to do all the measurements your calipers are capable of? Ever wonder what’s inside those things? We did too.
To every gadget, tool, or toy, you can reasonably think: ‘Sure I could buy this… but can I make it myself?’ And that’s where [Ben] decided he could, and got to work. On a sea scooter, to be exact.
This sea scooter was to be a fully waterproof, hermetically sealed 3D-printed underwater personal propulsion device, with the extreme constraint that the entire hull and mechanical interfaces are printed in one go. No post-printing holes for shafts, connectors, or seals. It also meant [Ben] needed to embed all electronics, motor, magnetic gearbox, custom battery pack, wireless charging, and non-contact magnetic control system inside the print during the actual print process.
As [Ben] explains, both Bluetooth and WiFi ranges are laughable once underwater. He elegantly solves this with a reed-switch-based magnetic control system. The non-contact magnetic drive avoids shaft penetrations entirely. Power comes from a custom 8S LiFePO₄ pack, charged wirelessly through the hull. Lastly, everything’s wrapped in epoxy to make it as watertight as a real submarine.
The whole trick of ‘print-in-place’ is that [Ben] pauses the builder mid-print, and drops in each subsystem like a secret ingredient. Continuing, he tweaks the printer’s Z-offset, and onwards it goes. It’s tense, high-stakes work; a 14-hour print where one nozzle crash means binning hundreds of dollars’ worth of embedded components.
Still, [Ben] took the chance, and delivered a cool, fully packed and fully working sea scooter. Comment below to discuss the possibilities of building one yourself.
Having a chiller is often essential for the chemistry laboratory, but what if you’re somewhere without easy access to water, nevermind a mains outlet to plug your usual chiller into? In that case you can build a portable one that will happily run off the 12 VDC provided by a mobile source like the accessory outlet in a car while reusing the water from its reservoir, as demonstrated by [Markus Bindhammer] in a recent video.
The build uses a compressor-based freezer as the base, which is significantly more capable than the typical Peltier-cooled refrigerators that cannot cool as fast or efficiently. The changes he made involve running in- and outlet tubing into the freezer’s compartment, with a submerged 12 VDC water pump providing the water to the outlet. This pump is controlled by a variable speed controller board that’s put in a box on the outside with the power lead also sneaking into the freezer. With these modifications in place the freezer’s functionality isn’t significantly impacted, so it can be used as normal.
After filling the compartment with water, the lid is closed and the freezer engaged. The pump controller is then switched on, with the water flow adjusted to fit the distillation job at hand. Although in this case a fairly small freezer was modified, nobody is saying that you cannot also do it with a much larger freezer, and fill it with ice cream and other treats to help it and lab critters cool down faster.
No, of course not. Per Betteridge’s law, that’s the answer to any headline with a question mark. On the other hand, while a thermal printer might not cure ADHD, it can help treat it — according to [Laurie Hérault], to the point of curing his procrastination habit. Even if you don’t have ADHD, you probably do procrastinate sometimes, so this hack is worth a look.
The printer itself is a key hardware portion of the hack, but the hack itself is purely organizational. [Laurie] started with post-its before adding automation. Before the post-it notes came a simple realization: [Laurie] could sit and play games for hours, but not buckle down for serious work for more than a few minutes, if he could even get started. (Who can’t relate?) That sent him down a rabbit hole reading about the psychology of what makes games so addictive — and the idea of “gamification” that was so popular in educational circles not long ago.
Unlike work, games give you a loop of unambiguous, instant, and continuous feedback to pump your dopamine circuits. [Laurie] uses the example of an FPS. You aim, you shoot — and either you miss, or you hit the target. Either way, there’s feedback. When you hit, your brain gives you dopamine. This fast loop of input -> feedback is what [Laurie] felt he was missing from his day.
You’d want to organize the post-its better than this. (Image by Pexels.)
That’s where the post-it notes came in. Post-its went up on a board with all of his tasks for the day; the input was his completing the tasks, and the feedback was taking them down, crumpling them up, and putting them into a clear jar that would serve as a score bar for his productivity. The feedback actually rewarded multiple senses this way: the tactility of crumpling paper, the sound of it, and the visual of the rising level of the jar.
A key insight [Laurie] had in this process is that many productivity apps (including gamifying ones) are focused too much on high-level tasks by default. “Clean the kitchen,” for example. That’s too big! It’s daunting, and it takes too long for that immediate, gamified feedback. Instead [Laurie] breaks down “Cleaning the Kitchen” into “Clean the dishes”, “Wipe the Counter”, “Take out the Trash”, et cetera. The smaller the steps, the more frequent the reward, and the easier it is to start them without exerting much willpower: just like a video game.
Of course writing all of those post-it notes gets tedious, especially for recurring and pre-scheduled tasks, and that tedium increases exponentially when breaking tasks down into the smallest possible chunks. That’s where the thermal printer came in. [Laurie] wrote a simple software utility to allow him to create high-level tasks, and break them down into small action items that are immediately sent to the thermal printer. After that, the system works just as it does with the post-it notes. He promises to share this software, but it does not seem to have yet been released. Hopefully he’s not procrastinating on that, or our faith in the process is ruined.
[Avi Gupta] recently sent in their LoRaSense RGB Pi HAT project. This “HAT” (Hardware Attached to Top) is for any Raspberry Pi with 40-pin header. The core of the build is the custom printed circuit board which houses the components and interconnects. The components include an SHT31 temperature and humidity sensor, an SX1278 LoRa module, and a 10 amp 220 VAC relay. The interconnects include support for UART, I2C, SPI, and WS2812B RGB LED interfaces as well as a stackable header for daisy chaining HATs.
The attached components in combination support a wide range of use cases. Possible uses for this Raspberry Pi HAT include smart home systems, agricultural projects, industrial monitoring, smart greenhouse, remote weather stations, or alerting systems. You can detect weather conditions, send and receive information, switch mains powered loads, and use RGB LEDs for status and alerting.
Despite being a readily-available source of useful plastic, massive numbers of disposable bottles go to waste every day. To remedy this problem (or take advantage of this situation, depending on your perspective) [Igor Tylman] created the PETmachine, an extruder to make 3D printer filament from PET plastic bottles.
The design of the extruder is fairly standard for such machines: a knife mounted to the frame slices the bottle into one long strip, which feeds through a heated extruder onto a spool which pulls the plastic strand through the system. This design stands out, though, in its documentation and ease of assembly. The detailed assembly guides, diagrams, and the lack of crimped or soldered connections all make it evident that this was designed to be built in a classroom. The filament produced is of respectable quality: 1.75 mm diameter, usually within a tolerance of 0.05 mm, as long as the extruder’s temperature and the spool’s speed were properly calibrated. However, printing with the filament does require an all-metal hotend capable of 270 ℃, and a dual-drive extruder is recommended.
One issue with the extruder is that each bottle only produces a short strand of filament, which isn’t sufficient for printing larger objects. Thus, [Igor] also created a filament welder and a spooling machine. The welder uses an induction coil to heat up a steel tube, inside of which the ends of the filament sections are pressed together to create a bond. The filament winder, for its part, can wind with adjustable speed and tension, and uses a moving guide to distribute the filament evenly across the spool, avoiding tangles.
These days, the personal MP3 player has been largely replaced by the the smartphone. However, [Justinas Petkauskas] still appreciates the iPod for its tactility and portability, and wanted to bring that vibe back. Enter JPL.mp3
The build is based around the ESP32-S3 microcontroller. It’s hooked up with a PCM5102 DAC hooked up over I2S to provide quality audio, along with a micro SD card interface for music storage, and a small IPS LCD. The best feature, though? The mechanical click-wheel which provides a very tactile way to scroll and interact with the user interface. Everything is assembled into a neat 3D printed case, with a custom four-layer PCB lacing all the electronics together.
On the software side, [Justinas] cooked up some custom software for organizing music on the device using a SQLite database. As he primarily listens to classical music, the software features fields for composer/piece and conductor, orchestra, or performer.
[Justinas] calls the final build “chunky, but nevertheless functional” and notes it is “vaguely reminiscent of classic iPods.” We can definitely see the fun in building your own personalized version of a much-enjoyed commercial product, for sure. Meanwhile, if you’re cooking up your own similar hardware, we’d certainly love to hear about it.
When Raspberry Pi’s new RP2350 MCU was released in 2024, it had a slight issue in that its GPIO pins would leak a significant amount of current when a pin is configured as input with the input buffer enabled. Known as erratum 9 (E9), it has now been addressed per the July 29 Product Change Note from Raspberry Pi for the A4 stepping along with a host of other hardware and software issues.
Although the PCN is for stepping A4, it covers both steppings A3 and A4, with the hardware fixes in A3 and only software (bootrom) fixes present in A4, as confirmed by the updated RP2350 datasheet. It tells us that A3 was an internal development stepping, ergo we should only be seeing the A4 stepping in the wild alongside the original defective A2 stepping.
When we first reported on the E9 bug it was still quite unclear what this issue was about, but nearly a month later it was officially defined as an input mode current leakage issue due to an internal pull-up that was too weak. This silicon-level issue has now finally been addressed in the A3 and thus new public A4 stepping.
Although we still have to see whether this is the end of the E9 saga, this should at least offer a way forward to those who wish to use the RP2350 MCU, but who were balking at the workarounds required for E9 such as external pull-downs.
Login
