open source

311 Articles

Open Source Hardware, How Open Do You Want It To Be?

March 7, 2025 by 43 Comments

In our wider community we are all familiar with the idea of open source software. Many of us run it as our everyday tools, a lot of us release our work under an open source licence, and we have a pretty good idea of the merits of one such document over another. A piece of open source software has all of its code released under a permissive licence that explicitly allows it to be freely reproduced and modified, and though some people with longer beards take it a little too seriously at times and different flavours of open source work under slightly different rules, by and large we’re all happy with that.

When it comes to open hardware though, is it so clear cut?  I’ve had more than one rant from my friends over the years about pieces of hardware which claim to be open-source but aren’t really, that I think this bears some discussion.

Open Source Hardware As It Should Be Done

To explore this, we’ll need to consider a couple of open source hardware projects, and I’ll start close to home with one of my own. My Single 8 home movie cartridge is a 3D printable film cartridge for a defunct format, and I’ve put everything necessary to create one yourself in a GitHub repository under the CERN OHL. If you download the file and load it into OpenSCAD you can quickly create an STL file for your slicer, or fiddle with the code and make an entirely new object. Open source at its most efficient, and everyone’s happy. I’ve even generated STLs ready to go for each of the supported ISO values. Continue reading “Open Source Hardware, How Open Do You Want It To Be?” →

Open Safety In The Auto Business: Renault Shares Its Battery Fire Suppression Tech

March 7, 2025 by 31 Comments

As consumers worldwide slowly make the switch from internal combustion vehicles to lower-carbon equivalents, a few concerns have appeared about electric vehicles. Range anxiety is ebbing away as batteries become bigger and chargers become more frequent, but a few well-publicized incidents have raised worries over fire safety.

Lithium-ion batteries can ignite in the wrong circumstances, and when they do so they are extremely difficult to extinguish. Renault has a solution, and in a rare moment for the car industry, they are sharing it freely for all manufacturers to use.

The innovation in question is their Fireman Access Port, a standardized means for a fire crew to connect up their hoses directly to the battery pack and attack the fire at its source. An opening is covered by an adhesive disk designed to protect the cells, but breaks under a jet of high-pressure water. Thermal runaway can then be halted much more easily.

The licensing terms not only allow use of the access port itself, but also require any enhancements be shared with the rest of the community of automakers using the system. This was the part which caught our interest, because even if it doesn’t come from the same place as the licences we’re used to, it sounds a lot like open source to us.

Oddly, this is not the first time Renault have open-sourced their technology, in the past they’ve shared an entire car.

Open-Source Random Numbers

February 20, 2025 by 26 Comments

Whether it’s a game of D&D or encrypting top-secret information, a wide array of methods are available for generating the needed random numbers with high enough entropy for their use case. For a tabletop game this might be a single die but for more sensitive applications a more robust method of generating random numbers is needed. Programmers might reach for a rand() function of some sort, but these pseudorandom numbers don’t cut the mustard for encryption. For that you’ll need a true random number generator (RNG), and this open-source hardware RNG uses one of the better methods we’ve seen.

The device, called RAVA, is based on a property found in many electronic devices called avalanche breakdown. Avalanche breakdown occurs when a high voltage (in this case approximately 25V) is applied in the reverse bias direction, with this device using a pair of Zener diodes. When this high voltage is applied, an “avalanche” of electrons occurs which allows the diodes conduct in the opposite direction that they would when they are forward biased. This isn’t a constant current flow, though; there are slight variations over time which can be amplified and used as the random number generator. The noise is amplified over a series of op amps and then fed to an ATmega32U4 microcontroller which can provide the user with 136.0 Kbit/s of random data.

Unlike other random number generators, this device is based on a method generally accepted to be truly random. Not only that, but since it’s based on discrete hardware it can be accessed directly for monitoring and replacement in case of faults, unlike other methods which are more “black boxes” and are more opaque in their processes which are thus harder to audit. We also appreciate it’s open-source nature as well, and for some more information on it be sure to check out the paper on it in IEEE. If you’re looking for something to generate random numbers but will also bring some extra flair to the next game night, take a look at this radioactive dice replacement.

Software In Progress

February 8, 2025 by 69 Comments

Open source software can be fantastic. I run almost exclusively open software, and have for longer than I care to admit. And although I’m not a serious coder by an stretch, I fill out bug reports when I find them, and poke at edge cases to help the people who do the real work.

For 3D modeling, I’ve been bouncing back and forth between OpenSCAD and FreeCAD. OpenSCAD is basic, extensible, and extremely powerful in the way that a programming language is, and consequently it’s reliably bug-free. But it also isn’t exactly user friendly, unless you’re a user who likes to code, in which case it’s marvelous. FreeCAD is much more of a software tool than a programming language, and is a lot more ambitious than OpenSCAD. FreeCAD is also a program in a different stage of development, and given its very broad scope, it has got a lot of bugs.

I kept running into some really serious bugs in a particular function – thickness for what it’s worth – which is known to be glitchy in the FreeCAD community. Indeed, the last time I kicked the tires on thickness, it was almost entirely useless, and there’s been real progress in the past couple years. It works at least sometimes now, on super-simple geometries, and this promise lead me to find out where it still doesn’t work. So I went through the forums to see what I could do to help, and it struck me that some people, mostly those who come to FreeCAD from commercial programs that were essentially finished a decade ago, have different expectations about the state of the software than I do, and are a lot grumpier.

Open source software is working out its bugs in public. Most open source is software in development. It’s growing, and changing, and you can help it grow or just hang on for the ride. Some open-source userland projects are mature enough that they’re pretty much finished, but the vast majority of open-source projects are coding in public and software in progress.

It seems to me that people who expect software to be done already are frustrated by this, and that when we promote super-star open projects like Inkscape or Blender, which are essentially finished, we are doing a disservice to the vast majority of useful, but still in progress applications out there that can get the job done anyway, but might require some workarounds. It’s exactly these projects that need our help and our bug-hunting, but if you go into them with the “finished” mentality, you’re setting yourself up for frustration.

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Time Vs Money, 3D Printer Style

February 1, 2025 by 28 Comments

A few months ago, Hackaday’s own Al Williams convinced me to buy a couple of untested, returned-to-manufacturer 3D printers. Or rather, he convinced me to buy one, and the incredible success of the first printer spurred me on to the second. TL;DR: Lightning didn’t strike twice, but I’d still rate it as worth my time. This probably isn’t a good choice for your first printer, but if you’ve done the regular maintenance on your first printer already, I’d recommend it for your second or twelfth.

As background, Al has been volunteering with local schools to teach a 3D printing summer class, and this means outfitting them with a 3DP lab on the dirt cheap. His secret is to buy last year’s model which has all of the features he needs – most importantly for the kids, automatic bed height probing – but to buy it from the scratch-and-dent shelf at Creality. Why? Because they are mid-grade printers, relatively new, but on deep discount.

How deep? I found an essentially endless supply of printers that retail for $300 on discount for $90 each. The catch? It might work, it might not. I bought my son one, because I thought that it would at least make a good project for us to work on together. Those plans were spoiled – it worked absolutely flawlessly from the moment we bolted it together, and he runs 24-hour jobs on the thing without fear. From the look of the build plate, it had been used exactly once and returned for whatever reason. Maybe the owner just didn’t want a 3D printer?

The siren song of straightforward success was too much for me to resist, and I picked another up to replace my aging A8 which was basically a kit for a 3D printer, and not a particularly good one at that, but could be made to work. My scratch-and-dent Creality came with a defective bed-touch sensor, which manifest itself as a random absolute refusal to print.

I took it apart, but the flaw is in the design of the V1 touch sensors – the solenoid requires more current to push down than the 3DP motherboard can reliably deliver. It works 100% of the time on my bench power supply, but in situ it fails about 30% of the time, even after hitting it with graphite and making sure everything is mechanically sound. Creality knows this and offers a free trade-in, just not for me. The new version of the Creality probe costs $50 new, but you can get cheap knock-off BL Touch models for $14. Guess what I did?

And guess what bit me? The cheapo touch probe descends a bit slower than the Creality version should, and the firmware is coded to time-out in an extra-short timeframe. Thankfully, Creality’s modifications to Marlin are all open source, and I managed to tweak and flash a new firmware that made it work 100% of the time, but this was at a cost of probably eight hours of bug-hunting, part-ordering, and firmware-compiling. That said, I got some nice extra features along the way, which is the advantage of a printer running open-source firmware.

So my $300 printer cost me $105, plus eight hours of labor. I only charge one coffee per hour for fun hardware debugging tasks, but you may have a different valuation. Taken together with my son’s printer, we have $600 worth of printer for under $200 plus labor, though, which starts to sound a little better.

Is gambling on an untested return 3D printer worth it? For us, I would say it was, and I’d do it again in a few years. For now, though, we’ve got three printers running and that’s all we need. Have you gone down this perilous path?

This article is part of the Hackaday.com newsletter, delivered every seven days for each of the last 200+ weeks. It also includes our favorite articles from the last seven days that you can see on the web version of the newsletter. Want this type of article to hit your inbox every Friday morning? You should sign up!

38C3: Towards An Open WiFi MAC Stack On ESP32

December 28, 2024 by 15 Comments

At the 38th Chaos Communications Congress, [Frostie314159] and [Jasper Devreker] gave us a nice update on their project to write an open-source WiFi stack for the ESP32. If you’re interested in the ESP32 or WiFi in general, they’ve also got a nice deep dive into how that all works.

On the ESP32, there’s a radio, demodulator, and a media access controller (MAC) that takes care of the lowest-level, timing-critical bits of the WiFi protocol. The firmware that drives the MAC hardware is a licensed blob, and while the API or this blob is well documented — that’s how we all write software that uses WiFi after all — it’s limited in what it lets us do. If the MAC driver firmware were more flexible, we could do a lot more with the WiFi, from AirDrop clones to custom mesh modes.

The talk starts with [Jasper] detailing how he reverse engineered a lot of Espressif’s MAC firmware. It involved Ghidra, a Faraday cage, and a lucky find of the function names in the blob. [Frostie] then got to work writing the MAC driver that he calls Ferris-on-Air. Right now, it’s limited to normal old station mode, but it’s definite proof that this line of work can bear fruit.

This is clearly work in progress — they’ve only been at this for about a year now — but we’ll be keeping our eyes on it. The promise of the ESP32, and its related family of chips, being useful as a more general purpose WiFi hacking tool is huge.

A Robot Meant For Humans

November 26, 2024 by 11 Comments

Although humanity was hoping for a more optimistic robotic future in the post-war era, with media reflecting that sentiment like The Jetsons or Lost in Space, we seem to have shifted our collective consciousness (for good reasons) to a more Black Mirror/Terminator future as real-world companies like Boston Dynamics are actually building these styles of machines instead of helpful Rosies. But this future isn’t guaranteed, and a PhD researcher is hoping to claim back a more hopeful outlook with a robot called Blossom which is specifically built to investigate how humans interact with robots.

For a platform this robot is not too complex, consisting of an accessible frame that can be laser-cut from wood with only a few moving parts controlled by servos. The robot is not too large, either, and can be set on a desk to be used as a telepresence robot. But Blossom’s creator [Michael] wanted this to help understand how humans interact with robots so the latest version is outfitted not only with a large language model with text-to-speech capabilities, but also with a compelling backstory, lore, and a voice derived from Animal Crossing that’s neither human nor recognizable synthetic robot, all in an effort to make the device more approachable.

To that end, [Michael] set the robot up at a Maker Faire to see what sorts of interactions Blossom would have with passers by, and while most were interested in the web-based control system for the robot a few others came by and had conversations with it. It’s certainly an interesting project and reminds us a bit of this other piece of research from MIT that looked at how humans and robots can work productively alongside one another.