SLR To DSLR Conversion Becomes Full Camera

August 22, 2023 by Bryan Cockfield 8 Comments

At least as far as the inner workings are concerned, there’s not a whole lot of difference between an single-lens reflex (SLR) camera that uses film and a digital SLR (DSLR) camera that uses an electronic sensor except the method for capturing the image. So adding the digital image sensor to a formerly analog camera like this seemed like an interesting project for [Wenting Zhang]. But this camera ballooned a little further than that as he found himself instead building a complete, full-frame digital camera nearly from scratch.

The camera uses a full-frame design and even though the project originally began around the SLR mechanism, in the end [Wenting] decided not to keep this complex system in place. Instead, to keep the design simple and more accessible a mirrorless design is used with an electronic viewfinder system. It’s also passive M lens mount, meaning that plenty of manual lenses will be available for this camera without having to completely re-invent the wheel.

As far as the sensor goes, [Wenting] wanted something relatively user-friendly with datasheets available so he turned to industrial cameras to find something suitable, settling on a Kodak charge-coupled device (CCD) for the sensor paired with an i.MX processor. All of the electronics have publicly-available datasheets which is important for this open-source design. There’s a lot more work that went into this build than just picking parts and 3D printing a case, though, and we’d definitely recommend anyone interested to check out the video below for how this was all done. And, for those who want to go back to the beginnings of this project and take a different path, it’s definitely possible to convert an analog SLR to a digital one.

Continue reading “SLR To DSLR Conversion Becomes Full Camera” →

DIY Eye Tracking For VR Headsets, From A To Z

August 5, 2023 by Donald Papp 4 Comments

Eye tracking is a useful feature in social virtual reality (VR) spaces because it really enhances presence and communication when one’s avatar has a realistic gaze. Most headsets lack this feature, but EyeTrackVR has a completely open source solution ready for anyone willing to put it together.

Camera is visible in lower right corner.

EyeTrackVR is a combination of hardware, software, and 3D printable mounts for attaching a pair of microcontroller boards, cameras, and IR LEDs to just about any existing VR headset out there. An ESP32-based board and tiny camera module watches each eyeball, and under IR illumination the pupil presents as an easily-identified round black area. Software takes care of turning the camera’s view of the pupil into a gaze direction value that can be plugged into other software.

The project is still under active development, but in its current state is perfectly suitable for creating a functional system that can integrate into a variety of existing headsets with printed mounting brackets. Interested? Check out the intro and if it sounds up your alley, dive into the build guide which spells out everything you need to know. Check out the video below for a demo of EyeTrackVR working in VRChat, along with an overview of software support.

We’ve seen headsets built to custom specs that integrate eye tracking, but even if one is repackaging an existing headset that’s a perfect opportunity to include this feature.

Continue reading “DIY Eye Tracking For VR Headsets, From A To Z” →

Open-Source Firmware For Soldering Irons

August 2, 2023 by Bryan Cockfield 23 Comments

For most of us, the first soldering iron we pick up to start working on electronics has essentially no features at all. Being little more than resistive heaters plugged straight into the wall with perhaps a changeable tip, there’s not really even a need for a power switch. But doing anything more specialized than through-hole PCB construction often requires a soldering iron with a little more finesse, though. Plenty of “smart” soldering irons are available for specialized soldering needs now, and some are supported by the open-source IronOS as well.

The project, formerly known as TS100, is a versatile soldering iron control firmware that started as an alternative firmware for only the TS100 soldering iron. It has since expanded to have compatibility with several other soldering irons and hosts a rich set of features, including temperature control, motion activation, and the ability to temporarily increase the temperature when using the iron. The firmware is also capable of working with irons that use batteries as well as irons that use USB power delivery.

For anyone with a modern smart soldering iron, like the Pinecil or various Miniware iron offerings, this firmware is a great way of being able to gain fine control over the behavior of one’s own soldering iron, potentially above and beyond what the OEM firmware can do. If you’re still using nothing more than a 30W soldering iron that just has a wall plug, take a look at a review we did for the TS100 iron a few years ago to see what you’re missing out on.

Photo via Wikimedia Commons

An Open-Source, Free Circuit Simulator

July 30, 2023 by Bryan Cockfield 60 Comments

The original circuit simulation software, called the Simulation Program with Integrated Circuit Emphasis, or SPICE as it is more commonly known, was originally developed at the University of Califorina Berkeley in the 1970s with an open-source license. That’s the reason for the vast versions of SPICE available now decades after the original was released, not all of which are as open or free as we might like. Qucs is a GPL circuit simulator. And if you want the GUI option, you might want to try out QucsStudio, which uses Qucs under the hood, and is free to use, but binary-only.

(Editor’s note: the author was confused between the GPL open-source Qucs and the closed-source, binary-only QucsStudio. We’ve cleaned that up.)

QucsStudio supports a wide range of circuit components and models much in the same fashion as other more popular SPICE programs, including semiconductor devices, passive components, and digital logic gates. Qucs also utilizes SPICE-based simulation, which can model various types of circuit behavior, such as DC, AC, transient, and small-signal analysis.

Unfortunately there are only Windows versions available, and although some might have some success running it under WINE. There are plenty of other options for those of us running non-Windows operating systems though. Here’s a review of 30 of them.

Thanks to [Electroagenda] for the tip!

When Is Open Source AI Not Open Source AI?

July 21, 2023 by Jenny List 18 Comments

The world of AI is abuzz, or at least parts of it are, at the news of Meta’s release of Llama 2. This is an AI text model which is thought to surpass ChatGPT in capabilities, and which the social media turned VR turned own all your things company wants you to know is open to all. That’s right, the code is open source and you can download the model, and Meta want you to feel warm and fuzzy about it. Unfortunately all is not as it seems, because of course the model isn’t open-source and is subject to a licensing restriction which makes it definitely not free of charge for larger users. This is of course disappointing to anyone hoping for an AI chatbot without restrictions, but we’re guessing Meta would prefer not to inadvertently enable a competitor.

Happily for the open source user large or small who isn’t afraid of a little work there’s an alternative in the form of OpenLLaMA, but we understand that won’t be for all users. Whichever LLM you use though, please don’t make the mistake of imagining that it possesses actual intelligence.

Thanks to the CoupledAI team for the tip!

Open Source OLED Nametag Is Full Of Features

July 20, 2023 by Donald Papp 5 Comments

Ever wanted a sweet OLED nametag with fancy features like daylight readability, automatic brightness adjustment, GIF animation support, all-day runtime, easy web interface, and more? [TobleMiner]’s OLED Nametag is the project you want to keep an eye on in that case.

It’s still an early prototype, but the feature list looks great and works with a variety of OLED modules that are easily available. The enclosure can be 3D printed, and while there is very little spare room inside the housing, [TobleMiner] has clearly made the most of all available space. Some PCB fab houses offer component placement these days, and the board is designed with exactly that in mind.

We’ve seen a batteryless E-paper display make a serviceable nametag in the past, and while those offer high contrast and wide viewing angles, they lack the sort of features this project is bursting at the seams with. Affordable access to good components and the ability to have high-quality PCBs made on demand has really raised the bar in terms of what a hacker project can work with in recent years, and we love to see it expressed in projects like this one.

Quetzal-1 Satellite Goes Open Source

July 4, 2023 by Jonathan Bennett 30 Comments

Back in 2020, students from Universidad Del Valle De Guatemala (UVG) pulled off a really impressive feat, designing and building a CubeSat that lasted a whopping 211 days in orbit. In addition to telemetry and radio equipment, it carried a black-and-white camera payload.

But it turns out space is hard. The first pictures were solid black or white, with the automatic exposure process failing pretty badly. A pair of good pictures were taken by waiting until the satellite was passing over Guatemala during sunrise or sunset. A hung I2C bus led to battery drain, and the team tried a system reset to clear the hung state. Sadly the craft never came back to life after the reset, likely because of one of the Lithium-Ion battery cells failed completely in the low charge state.

That was 2020, so why are we covering it now? Because the project just released a massive trove of open source design documents, the software that ran on the satellite and ground station, and all the captured telemetry from the flight. It’s the ultimate bootstrap for anyone else designing a CubeSat, and hopefully provides enough clues to avoid some of the same issues.

Even though the mission had problems, it did achieve a lot of milestones, including the first picture of Earth taken by a Central American satellite. Even coming online and making radio contact from orbit to an earthbound station is quite a feat. The team is already looking forward to Quetzal-2, so stay tuned for more!

And if you want the details on the Quetzal-1 design, and what went wrong with the electrical system, both PDF papers have been released. Seeing more open source in space is an encouraging development, and one that should continue to grow as the cost of payloads to orbit continues to fall. We’ve covered the UPSat satellite, the PyCubed framework, and even the RTL-SDR for listening to satellite radio traffic.