Why is it always a helium leak? It seems whenever there’s a scrubbed launch or a narrowly averted disaster, space exploration just can’t get past the problems of helium plumbing. We’ve had a bunch of helium problems lately, most famously with the leaks in Starliner’s thruster system that have prevented astronauts Butch Wilmore and Suni Williams from returning to Earth in the spacecraft, leaving them on an extended mission to the ISS. Ironically, the launch itself was troubled by a helium leak before the rocket ever left the ground. More recently, the Polaris Dawn mission, which is supposed to feature the first spacewalk by a private crew, was scrubbed by SpaceX due to a helium leak on the launch tower. And to round out the helium woes, we now have news that the Peregrine mission, which was supposed to carry the first commercial lander to the lunar surface but instead ended up burning up in the atmosphere and crashing into the Pacific, failed due to — you guessed it — a helium leak. Continue reading “Hackaday Links: September 1, 2024”→
Additive manufacturing (AM) has been getting a lot of attention over the years, with its use in construction a recurring theme. Generally this brings to mind massive 3D printers that are carted to construction sites and assemble entire homes on the spot. That’s the perspective with which a recent ZDNet article by [Rajiv Rao] opens, before asking whether AM in construction is actually solving any problems. As [Rajiv] notes, the main use of such on-site AM construction is for exclusive, expensive designs, such as ICON’s House Zero which leans into the extruded concrete printing method.
Their more reasonable Wolf Ranch residential homes in Texas also use ICON’s Vulcan II printer to print walls out of concrete, with a roof, electrical wiring, plumbing, etc. installed afterwards. Prices for these Wolf Ranch 3 to 4 bedroom houses range from about $450,000 to $600,000, and ICON has been contracted by NASA to work a way to 3D print structures on the Moon out of regolith.
3D printed home by WASP out of clay. (Credit: WASP)
Naturally, none of these prices are even remotely in the range of the first-home buyers, or the many economically disadvantaged who make up a sizable part of the population in the US and many other nations in the Americas, Africa, etc. To make AM in construction economically viable, it would seem that going more flatpack and on-site assembly is the way to go, using the age-old pre-fabrication (prefab) method of constructions.
This is the concept behind the University of Maine’s BioHome3D, which mainly uses PLA, wood fiber and similar materials to create modules that contain insulation in the form of wood fiber and cellulose. These modules are 3D printed in a factory, after which they’re carted off to the construction site for assembly, pretty much like any traditional prefab home, just with the AM step and use of PLA rather than traditional methods.
Prefab is a great way to speed up construction and already commonly used in the industry, as modules can have windows, doors, insulation, electrical wiring, plumbing, etc. all installed in the factory, with on-site work limited to just final assembly and connecting the loose bits. The main question thus seems to be whether AM in prefab provides a significant benefit, such as in less material wasted by working from (discarded) wood pulp and kin.
While in the article [Rajiv] keeps gravitating towards the need to use less concrete (because of the climate) and make homes more affordable through 3D printing, AM is not necessarily the panacea some make it out to be, due to the fact that houses are complex structures that have to do much more than provide a floor, walls and a roof. If adding a floor (or two) on top of the ground floor, additional requirements come into play, before even considering aspects like repairability which is rarely considered in the context of AM construction.
Even when the boss is away, the show must go on, so Dan slid back behind the guest mic and teamed up with Tom to hunt down the freshest of this week’s hacks. It was a bit of a chore, with a couple of computer crashes and some side-quests down a few weird rabbit holes, but we managed to get things together in the end.
Tune in and you’ll hear us bemoan HOAs and celebrate one ham’s endless battle to outwit them, no matter what the golf cart people say about his antennas. Are you ready to say goodbye to the magnetic stripe on your credit card? We sure are, but we’re not holding our breath yet. Would you 3D print a 55-gallon drum? Probably not, but you almost can with a unique Cartesian-polar hybrid printer. And, if you think running MS-DOS on a modern laptop is hard, guess again — or, maybe you just have to get really lucky.
We also took a look at a digital watch with a beautiful display, a hacked multimeter, modern wardriving tools, switchable magnets, and debate the eternal question of v-slot wheels versus linear bearings. And finally, you won’t want to miss our look at what’s new with 3D scanning, and the first installment of Kristina’s new “Boss Byproducts” series, which delves into the beauty of Fordite.
This week on the Podcast, we have something a little different for you. Elliot is on vacation, so Tom was in charge of running the show and he had Kristina in the hot seat.
First up in the news: the 2024 Tiny Games Challenge is still underway and has drawn an impressive 44 entries as of this writing. You have until 9AM PDT on September 10th to show us your best tiny game, whether that means tiny hardware, tiny code, or a tiny BOM.
Then it’s on to What’s That Sound, which Tom and Kristina came up with together, so there will be no pageantry about guessing. But can you get it? Can you figure it out? Can you guess what’s making that sound? If you can, and your number comes up, you get a special Hackaday Podcast t-shirt.
Now it’s on to the hacks, beginning with an open-source liquid-fueled rocket and a really cool retro trackball laptop. Then we’ll discuss screwdriver mange, the Wow! signal, and whether you’re using you’re calipers incorrectly. Finally, we look at a laptop that that isn’t really a laptop, and one simple trick to keep things aligned on your laser engraver.
Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Download in DRM-free MP3 and savor at your leisure.
If you’re running a big factory, you’ve probably got a massively expensive contract with a major programmable logic controller (PLC) manufacturer. One shudders to think about the cost of the service subscription on that one. If you’re working on a smaller scale, though, you might consider a DIY PLC like this one from [Mr Innovative.]
PLCs are rarely cutting-edge; instead, they’re about reliability and compliance with common industry standards. To that end, this design features the ATmega328P. Few other microcontrollers are as well understood or trusted as that one. The device is compatible with RS232 and RS485 and will run off 24 VDC, both of which you would find in a typical industrial environment. It offers 24 V digital inputs and outputs, as well as analog inputs and outputs from 0 to 10 V. [Mr Innovative] demonstrates it by hooking up a DWIN human-machine interface (HMI) for, well… human interaction, and a variable frequency drive to run a motor.
If you want to run a basic industrial-lite system but can’t afford the real industrial price tag, you might enjoy tinkering around at this level first. It could be a great way to get a simple project up and running without breaking the bank. Video after the break.
As battery-to-grid and vehicle-to-home technologies become increasingly mainstream, the potential for repurposing electric vehicle (EV) batteries has grown significantly. No longer just a niche pursuit, using retired EV batteries for home energy storage has become more accessible and appealing, especially as advancements in DIY solutions continue to emerge. Last year, this project by [Dala] showcased how to repurpose Nissan Leaf and Tesla Model 3 battery packs for home energy storage using a LilyGO ESP32, simplifying the process by eliminating the need for battery disassembly.
In the past few months, this project has seen remarkable progress. It now supports over 20 different solar inverter brands and more than 25 EV battery models. The most exciting development, however, is the newly developed method for chaining two EV packs together to create a single large super-battery. This breakthrough enables the combination of, for example, two 100kWh Tesla packs into a massive 200kWh storage system. This new capability offers an accessible and affordable way to build large-scale DIY home powerwalls, providing performance that rivals commercial systems at a fraction of the cost.
With these advancements, the possibilities for creating powerful, cost-effective energy storage solutions have expanded significantly. We do however stress to put safety first at all times.
It could happen to anyone of us: suddenly you got this inkling of an idea for a product that you think might just be pretty useful or even cool. Some of us then go on to develop a prototype and manage to get enough seed funding to begin the long and arduous journey to turn a sloppy prototype into a sleek, mass-produced product. This is basically the story of how the Fitbit came to be, with a pretty in-depth article by [Tekla S. Perry] in IEEE Spectrum covering the development process and the countless lessons learned along the way.
Of note was that this idea for an accelerometer-based activity tracker was not new in 2006, as a range of products already existed, from 1960s mechanical pedometers to 1990s medical sensors and the shoe-based Nike+ step tracker that used Apple’s iPod with a receiver. Where this idea for the Fitbit was new was that it’d target a wide audience with a small, convenient (and affordable) device. That also set them up for a major nightmare as the two inventors were plunged into the wonderfully terrifying world of industrial design and hardware development.
One thing that helped a lot was outsourcing what they could to skilled people and having solid seed funding. This left just many hardware decisions to make it as small as possible, as well as waterproof and low-power. The use of the ANT protocol instead of Bluetooth saved a lot of battery, but meant a base station was needed to connect to a PC. Making things waterproof required ultrasonic welding, but lack of antenna testing meant that a closed case had a massively reduced signal strength until a foam shim added some space. The external reset pin on the Fitbit for the base station had a low voltage on it all the time, which led to corrosion issues, and so on.
While much of this was standard development and testing fun, the real challenge was in interpreting the data from the accelerometer. After all, what does a footstep look like to an accelerometer, and when is it just a pothole while travelling by car? Developing a good algorithm here took gathering a lot of real-world data using prototype hardware, which needed tweaking when later Fitbits moved from being clipped-on to being worn on the wrist. These days Fitbit is hardly the only game in town for fitness trackers, but you can definitely blame them for laying much of the groundwork for the countless options today.
![Maker [Dala] showing powerwall statistics](https://hackaday.com/wp-content/uploads/2024/08/diy-batteries-800.jpg?w=600&h=450)
