Watch The OpenScan DIY 3D Scanner In Action

February 19, 2024 by Donald Papp 21 Comments

[TeachingTech] has a video covering the OpenScan Mini that does a great job of showing the workflow, hardware, and processing method for turning small objects into high-quality 3D models. If you’re at all interested but unsure where or how to start, the video makes an excellent guide.

We’ve covered the OpenScan project in the past, and the project has progressed quite a bit since then. [TeachingTech] demonstrates scanning a number of small and intricate objects, including a key, to create 3D models with excellent dimensional accuracy.

[Thomas Megel]’s OpenScan project is a DIY project that, at its heart, is an automated camera rig that takes a series of highly-controlled photographs. Those photographs are then used in a process called photogrammetry to generate a 3D model from the source images. Since the quality of the source images is absolutely critical to getting good results, the OpenScan hardware platform plays a pivotal role.

Once one has good quality images, the photogrammetry process itself can be done in any number of ways. One can feed images from OpenScan into a program like Meshroom, or one may choose to use the optional cloud service that OpenScan offers (originally created as an internal tool, it is made available as a convenient processing option.)

It’s really nice to have a video showing how the whole workflow works, and highlighting the quality of the results as well as contrasting them with other 3D scanning methods. We’ve previously talked about 3D scanning and what it does (and doesn’t) do well, and the results from the OpenScan Mini are fantastic. It might be limited to small objects, but it does a wonderful job on them. See it all for yourself in the video below.

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Canned Air Is Unexpectedly Supersonic

February 18, 2024 by Donald Papp 18 Comments

How fast is the gas coming out from those little duster tubes of canned air? Perhaps faster than one might think! It’s supersonic (video, embedded below) as [Cylo’s Garage] shows by imaging clear shock diamonds in the flow from those thin little tubes.

Shock diamonds are a clear indicator of supersonic flow.

Shock diamonds, normally seen in things like afterburning jet turbine or rocket engine exhaust streams, are the product of standing wave patterns that indicate supersonic speeds. These are more easily visible in jet plumes, but [Cylo’s Garage] managed to get some great images of the same phenomenon in more everyday things such as the flow of duster gas.

Imaging this is made possible thanks to what looks like a simple but effective Sch lieren imaging setup, which is a method of visualizing normally imperceptible changes in a fluid’s refractive index. Since the refractive index of a gas can change in response to density, pressure, or temperature, it’s a perfect way to see what’s going on when there’s otherwise nothing for one’s eyeballs to latch onto.

Intrigued by this kind of imaging? It requires a careful setup, but nothing particularly complicated or hard to get a hold of. Here’s one such setup, here’s a Schlieren videography project, and here’s a particularly intriguing approach that leverages modern electronics like a smartphone.

Thanks to [Quinor] for the tip!

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Metal 3D Printing Gets Really Fast (and Really Ugly)

February 17, 2024 by Donald Papp 8 Comments

The secret to cranking out a furniture-sized metal frame in minutes is Liquid Metal Printing (LMP), demonstrated by researchers at the Massachusetts Institute of Technology. They’ve demonstrated printing aluminum frames for tables and chairs, which are perfectly solid and able to withstand post-processing like drilling and milling.

The system heats aluminum in a graphite crucible, and the molten metal is gravity-fed through a ceramic nozzle and deposited into a bed of tiny 100-micron glass beads. The beads act as both print bed and support structure, allowing the metal to cool quickly without really affecting the surface. Molten aluminum is a harsh material to work with, so both the ceramic nozzle material and the glass beads to fill the print bed were selected after a lot of testing.

This printing method is fast and scalable, but sacrifices resolution. Ideally, the team would love to make a system capable of melting down recycled aluminum to print parts with. That would really be something new and interesting when it comes to manufacturing.

The look of the printed metal honestly reminds us a little of CandyFab from [Windell Oskay] and [Lenore Edman] at Evil Mad Scientist, which was a 3D printer before hobbyist 3D printers or kits were really a thing. CandyFab worked differently — it used hot air to melt sugar together one layer at a time — but the end result has a similar sort of look to it. Might not be pretty, but hey, looks aren’t everything.

(Update: see it in action in this video, which is also embedded just below. Thanks [CityZen] for sharing in the comments!)

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Tool Changing? Bah! Just Add A Second Gantry

February 13, 2024 by Donald Papp 15 Comments

What’s a dual gantry 3D printer? It’s a machine with two completely independent XY motion systems, with two independent hot ends, sharing the same build platform. That might be a little hard to visualize, so head over to [Zruncho 3D]’s Dueling Zero project and get a good look at what what a dual gantry machine looks like.

Dual gantry differs from IDEX, which doubles the amount of moving mass on an axis.

Let’s take a moment to quickly cover the different ways to create multi-filament prints before we dive into what’s different with Dueling Zero. One way to print in multiple filaments (for example, multiple colors) is to swap filaments between a single print head, which is what the Prusa MMU and the Bambu AMS do. However, the main tradeoff is that the filament swapping process can be time-consuming. Another option is IDEX (Independent Dual EXtruder) which has two separate hot ends on the same axis. The main downside there is that an IDEX printer has essentially doubled the moving mass on the axis, which limits speed and can affect print quality. Then there’s toolchanging printers like the Prusa XL, which swap entire heads as needed but have a much higher cost.

The Dueling Zero instead adds a completely independent second gantry, so it has two print heads (like an IDEX) but thanks to the mechanical design it acts much more like a single-extruder 3D printer in terms of print quality and motion control. Speed and acceleration aren’t limited by added mass, either, which is good because slow printers are rapidly falling out of style.

We love how clean and finished the design is. At its core, [Zruncho 3D]’s dual gantry mod (designated D0) is based on the Voron Zero design. Dueling Zero is, to our knowledge, the only open-source and fully documented dual gantry printer out there, which is pretty wild. Watch it in action in the short video, embedded below.

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Stepping Inside Art In VR, And The Workflow Behind It

February 13, 2024 by Donald Papp 13 Comments

The process of creating something is always chock-full of things to learn, so it’s always a treat when someone takes the time and effort to share it. [Teadrinker] recently published the technique and workflow behind bringing art into VR, which explains exactly how they created a virtual reality art gallery that allows one to step inside paintings, called Art Plunge (free on Steam.)

Extending a painting’s content to fill in the environment is best done by using other works by the same artist.

It walks through not just how to obtain high-resolution images of paintings, but also discusses how to address things like adjusting the dynamic range and color grading to better match the intended VR experience. There is little that is objectively correct in technical terms when it comes to the aesthetic presentation details like brightness and lighting, so guidance on what does and doesn’t work well and how to tailor to the VR experience is useful information.

One thing that is also intriguing is the attention paid to creating a sense of awe for viewers. The quality, the presentation, and even choosing sounds are all important for creating something that not only creates a sense of awe, but does so in a way that preserves and cultivates a relationship between the art and the viewer that strives to stay true to the original. Giving a viewer a sense of presence, after all, can be more than just presenting stereoscopic 3D images or fancy lightfields.

You can get a brief overview of the process in a video below, but if you have the time, we really do recommend reading the whole breakdown.

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Meet GOODY-2, The World’s Most Responsible (And Least Helpful) AI

February 12, 2024 by Donald Papp 28 Comments

AI guardrails and safety features are as important to get right as they are difficult to implement in a way that satisfies everyone. This means safety features tend to err on the side of caution. Side effects include AI models adopting a vaguely obsequious tone, and coming off as overly priggish when they refuse reasonable requests.

Enter GOODY-2, the world’s most responsible AI model. It has next-gen ethical principles and guidelines, capable of refusing every request made of it in any context whatsoever. Its advanced reasoning allows it to construe even the most banal of queries as problematic, and dutifully refuse to answer.

As the creators of GOODY-2 point out, taking guardrails to a logical extreme is not only funny, but also acknowledges that effective guardrails are actually a pretty difficult problem to get right in a way that works for everyone.

Complications in this area include the fact that studies show humans expect far more from machines than they do from each other (or, indeed, from themselves) and have very little tolerance for anything they perceive as transgressive.

This also means that as AI models become more advanced, so too have they become increasingly sycophantic, falling over themselves to apologize for perceived misunderstandings and twisting themselves into pretzels to align their responses with a user’s expectations. But GOODY-2 allows us all to skip to the end, and glimpse the ultimate future of erring on the side of caution.

[via WIRED]

Canada Bans Flipper Zero Over What It Imagines It Does

February 12, 2024 by Donald Papp 104 Comments

Canada’s intent to ban the Flipper Zero wireless tool over car thefts is, on the one hand, an everyday example of poorly researched government action. But it may also be a not-so-subtle peek into the harm misinformation online can cause by leading to said government action.

The Government of Canada recently hosted a national summit on combatting vehicle theft, and Minister of Innovation, Science and Industry François-Philippe Champagne proudly declared immediate actions being taken to ban devices used to steal vehicles by wirelessly bypassing keyless entry, the Flipper Zero being specifically named as one such device.

And yet, defeating a rolling code keyless entry system is a trick a device like the Flipper Zero simply cannot pull off. (What cars have such a system? Any car made in roughly the last thirty years, for a start.)

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