USB Video Capture Devices: Wow! They’re All Bad!!

December 7, 2025 by Donald Papp 46 Comments

[VWestlife] purchased all kinds of USB video capture devices — many of them from the early 2000s — and put them through their paces in trying to digitize VHS classics like Instant Fireplace and Buying an Auxiliary Sailboat. The results were actually quite varied, but almost universally bad. They all worked, but they also brought unpleasant artifacts and side effects when it came to the final results. Sure, the analog source isn’t always the highest quality, but could it really be this hard to digitize a VHS tape?

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Lessons Learned After Trying MeshCore For Off-grid Text Messaging

December 6, 2025 by Donald Papp 65 Comments

[Michael Lynch] recently decided to delve into the world of off-grid, decentralized communications with MeshCore, because being able to communicate wirelessly with others in a way that does not depend on traditional communication infrastructure is pretty compelling. After getting his hands on a variety of hardware and trying things out, he wrote up his thoughts from the perspective of a hardware-curious software developer.

He ends up testing a variety of things: MeshCore firmware installed on a Heltec V3 board (used via an app over Bluetooth), a similar standalone device with antenna and battery built in (SenseCAP T-1000e, left in the header image), and a Lilygo T-Deck+ (right in the header image above). These all use MeshCore, which is built on and reportedly compatible with Meshtastic, a framework we have featured in the past.

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New Browser-based CAD System Is Best Friends With Triangle Meshes

December 4, 2025 by Donald Papp 41 Comments

Who’s interested in a brand new, from-scratch boundary representation (BREP) kernel? How about one that has no topological naming problem, a web-native parametric CAD front end to play with, and has CAD-type operations making friends with triangle meshes? If you’re intrigued, check out [mmiscool]’s BREP project.

Functioning (let alone feature-filled, or efficient) CAD systems are not a software project we see a whole lot of. Ones that represent models as genuine BREP structures but cleverly use mesh-based operations where it makes sense? Even less so.

In theory, CAD programs are simple: allow a user to define features, keep track of what they are and how they relate to one another, and perform operations on them as requested. In practice, it’s significant work. Chains of operations and dependencies easily become complex, volatile things and there is really no room for error.

Read [Arya Voronova]’s best practices for using FreeCAD to get a few hints as to what goes on behind the scenes in a modern CAD program, and the kinds of challenges the back end has to deal with, like the topological naming problem (TNP). A problem [mmiscool]’s implementation completely avoids, by the way.

There is a live demo at BREP.io which acts as a playground for the state of the project. You can get started by clicking the + button towards the top on the left panel to add features and operations to the history (like add a cube, then add chamfers or fillets, or extrude a face, and so on).

[mmiscool] points out that all computation is done client-side; even complex operations like fillets, lofts, and multi-body booleans execute directly in the browser with no need to be offloaded to a back end. BREP’s development is being documented on Hackaday.io and there is a video embedded below that gives an overview. Why don’t you give it a spin?

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The Database Powering America’s Hospitals May Not Be What You Expect

December 3, 2025 by Donald Papp 25 Comments

Ever heard of MUMPS? Both programming language and database, it was developed in the 1960s for the Massachusetts General Hospital. The goal was to streamline the increasingly enormous timesink that information and records management had become, a problem that was certain to grow unless something was done. Far from being some historical footnote, MUMPS (Massachusetts General Hospital Utility Multi-Programming System) grew to be used by a wide variety of healthcare facilities and still runs today. If you’ve never heard of it, you’re in luck because [Asianometry] has a documentary video that’ll tell you everything.

MUMPS had rough beginnings but ultimately found widespread support and use that continues to this day. As a programming language, MUMPS (also known simply as “M”) has the unusual feature of very tight integration with the database end of things. That makes sense in light of the fact that it was created to streamline the gathering, processing, and updating of medical data in a busy, multi-user healthcare environment that churned along twenty-four hours per day.

It may show its age (the term “archaic” — among others — gets used when it’s brought up) but it is extremely good at what it does and has a proven track record in the health care industry. This, combined with the fact that efforts to move to newer electronic record systems always seem to find the job harder than expected, have helped keep it relevant. Have you ever used MUMPS? Let us know in the comments!

And hey, if vintage programming languages just aren’t unusual enough for you, we have some truly strange ones for you to check out.

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LoRa Repeater Lasts 5 Years On PVC Pipe And D Cells

December 2, 2025 by Donald Papp 63 Comments

Sometimes it makes sense to go with plain old batteries and off-the-shelf PVC pipe. That’s the thinking behind [Bertrand Selva]’s clever LoRaTube project.

PVC pipe houses a self-contained LoRa repeater, complete with a big stack of D-size alkaline cells.

LoRa is a fantastic solution for long-range and low-power wireless communication (and popular, judging by the number of projects built around it) and LoRaTube provides an autonomous repeater, contained entirely in a length of PVC pipe. Out the top comes the antenna and inside is all the necessary hardware, along with a stack of good old D-sized alkaline cells feeding a supercap-buffered power supply of his own design. It’s weatherproof, inexpensive, self-contained, and thanks to extremely low standby current should last a good five years by [Bertrand]’s reckoning.

One can make a quick LoRa repeater in about an hour but while the core hardware can be inexpensive, supporting electronics and components (not to mention enclosure) for off-grid deployment can quickly add significant cost. Solar panels, charge controllers, and a rechargeable power supply also add potential points of failure. Sometimes it makes more sense to go cheap, simple, and rugged. Eighteen D-sized alkaline cells stacked in a PVC tube is as rugged as it is affordable, especially if one gets several years’ worth of operation out of it.

You can watch [Bertrand] raise a LoRaTube repeater and do a range test in the video (French), embedded below. Source code and CAD files are on the project page. Black outdoor helper cat not included.

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TARS-Like Robot Both Rolls, And Walks

December 1, 2025 by Donald Papp 7 Comments

[Aditya Sripada] and [Abhishek Warrier]’s TARS3D robot came from asking what it would take to make a robot with the capabilities of TARS, the robotic character from Interstellar. We couldn’t find a repository of CAD files or code but the research paper for TARS3D explains the principles, which should be enough to inspire a motivated hacker.

What makes TARS so intriguing is the simple-looking structure combined with distinct and effective gaits. TARS is not a biologically-inspired design, yet it can walk and perform a high-speed roll. Making real-world version required not only some inspired mechanical design, but also clever software with machine learning.

[Aditya] and [Abhishek] created TARS3D as a proof of concept not only of how such locomotion can be made to work, but also as a way to demonstrate that unconventional body and limb designs (many of which are sci-fi inspired) can permit gaits that are as effective as they are unusual.

TARS3D is made up of four side-by-side columns that can rotate around a shared central ‘hip’ joint as well as shift in length. In the movie, TARS is notably flat-footed but [Aditya] found that this was unsuitable for rolling, so TARS3D has curved foot plates.

The rolling gait is pretty sensitive to terrain variations, but the walking gait proved to be quite robust. All in all it’s a pretty interesting platform that does more than just show a TARS-like dual gait robot can be made to actually work. It also demonstrates the value of reinforcement learning for robot gaits.

A brief video is below in which you can see the bipedal walk in action. Not that long ago, walking robots were a real challenge but with the tools available nowadays, even a robot running a 5k isn’t crazy.

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How To Design 3D Printed Pins That Won’t Break

December 1, 2025 by Donald Papp 9 Comments

[Slant 3D] has a useful video explaining some thoughtful CAD techniques for designing 3D printed pins that don’t break and the concepts can be extended to similar features.

Sure, one can make pins stronger simply by upping infill density or increasing the number of perimeters, but those depend on having access to the slicer settings. If someone else is printing a part, that part’s designer has no actual control over these things. So how can one ensure sturdier pins without relying on specific print settings? [Slant 3D] covers two approaches.

The first approach includes making a pin thick, making it short (less leverage for stress), and adding a fillet to the sharp corner where the pin meets the rest of the part. Why? Because a rounded corner spreads stress out, compared to a sharp corner.

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