Open-Source Cell Phone Based On ESP32

Over the past decade or so, smartphones have exploded in popularity and seamlessly integrated themselves into nearly every aspect of most people’s lives. Although that comes with a few downsides as well, with plenty of people feeling that the smart phone makes it a little too easy to waste time and looking to switch to something simpler, like an older-style flip phone. If this style of phone is more your speed, take a look at this DIY cell phone which takes care of everything a phone really needs to do. (Google Translate from French)

The phone uses an ESP32 at its core, with a SIM800L GSM modem to interact with the cell network, including retrieving the system time. A small battery is included as well as all of the support circuitry for charging it as well as a USB interface that can communicate to a PC. The operating system for the phone is built from the ground up as well, with a touch screen interface allowing the user to make phone calls, send text messages, store contacts, and a few other basic features. There’s also a GPS application though, allowing the phone to know basic location information.

Another perk of this device is that its creator, [Gabriel], made the design schematics, print files for the case, and the operating system software completely open source for anyone to build this phone on their own. Everything is available on the project’s GitHub page. It’s a fairly remarkable achievement, especially considering [Gabriel] is only 16. And, if you’re not one to eschew modern smart phone technology there are some DIY smart phones available to build as well.

Thanks to [come2] for the tip!

Making Your Own VR Headset? Consider This DIY Lens Design

Lenses are a necessary part of any head-mounted display, but unfortunately, they aren’t always easy to source. Taking them out of an existing headset is one option, but one may wish for a more customized approach, and that’s where [WalkerDev]’s homebrewed “pancake” lenses might come in handy.

Engineering is all about trade-offs, and that’s especially true in VR headset design. Pancake lenses are compact units that rely on polarization to bounce light around internally, resulting in a very compact assembly at the cost of relatively poor light efficiency. That compactness is what [WalkerDev] found attractive, and in the process discovered that stacking two different Fresnel lenses and putting them in a 3D printed housing yielded a very compact pancake-like unit that gave encouraging results.

This project is still in development, and while the original lens assembly is detailed in this build log, there are some potential improvements to be made, so stay tuned if you’re interested in using this design. A DIY headset doesn’t mean you also must DIY the lenses entirely from scratch, and this option seems economical enough to warrant following up.

Want to experiment with mixing and matching optics on your own? Not only has [WalkerDev]’s project shown that off-the-shelf Fresnel lenses can be put to use, it’s in a way good news that phone-based VR is dead. Google shipped over 10 million cardboard headsets and Gear VR sold over 5 million units, which means there are a whole lot of lenses in empty headsets laying around, waiting to be harvested and repurposed.

Behold A DIY VR Headset Its Creator Will “Never” Build Again

Unsatisfied with commercial VR headset options, [dragonskyrunner] did what any enterprising hacker would: gathered parts over time and ultimately made their own. Behold the Hades Widebody (HWD), a DIY PC VR headset that aims for a wide field of view and even manages to integrate some face and eye tracking. (Editor’s note: link went dead in 2025. You’ll find the Hades Widebody here. Thanks [DragonSkyRunner] for keeping us in the loop!)

The Fresnel elements hugging the primary lenses provide a way of extending the display into the wearer’s peripheral vision.

[dragonskyrunner] is — and we quote — “NEVER building one of these again.” The reason is easily relatable to anyone who has spent a lot of time and effort creating something special: it does the job it was created for, but it also has limitations and is a lot of work. If one were to do it all over again, there would be a host of improvements and changes to consider. But one won’t be doing it all over again any time soon because it’s done now.

The good news is that [dragonskyrunner] made an effort to document things, so there is at least a parts list and enough details for any suitably motivated hacker to replicate the work and perhaps even put their own spin on it.

The Hades Widebody has a dual-lens arrangement and wide displays that aim to provide a wider field of view than most setups allow. There’s a main lens in front of the user’s eyes and a cut Fresnel lens providing a sort of extension to the side. [dragonskyrunner] claims that while there is certainly not a seamless transition between the lens elements, it does a better job than an Ambilight at providing a sense of visuals extending into the wearer’s peripheral vision.

The DIY spirit of making a piece of hardware to suit one’s own needs is exactly the sort of thing that would fit into our 2023 Cyberdeck content, and while a headset by itself isn’t quite enough to qualify (devices must have some form of usable input and output), it just might get those creative juices flowing.

IKEA LACK Table Becomes Extremely Affordable DIY Copy Stand

A copy stand is a tool used to capture images of photos, artwork, books, and things of a similar nature. It holds a camera perpendicular to a large and flat surface, upon which the subject rests.

A threaded rod provides effective vertical adjustment.

They are handy, but there’s no need to spend a lot when [BlandPasta]’s DIY copy stand based on a cheap IKEA LACK table can be turned into an economical afternoon project with the help of simple hardware and a few 3D printed parts.

The main structure comes from a mixture of parts from two LACK tables: one small and one normal-sized. A tabletop is used as the bed, and the square legs make up the structural parts with the help of some printed pieces. A threaded rod combined with some captive hardware provides a way to adjust the camera up and down with a crank, while one can manually slide the horizontal camera mount as needed to frame the subject appropriately.

This is a clever remix of IKEA parts, and the somewhat matte white finish of the LACK complements photography well. Adding some DIY LED lighting is about all it takes to get a perfectly serviceable copy stand that won’t break the bank.

Ask Hackaday: What’s Your “Tactical Tool” Threshold?

With few exceptions, every field has a pretty modest set of tools that would be considered the minimum for getting most jobs done. A carpenter can make do with tools that would fit in a smallish bag, while a mechanic can handle quite a few repairs with a simple set of socket wrenches and other tools. Even in electronics, a lot of repairs and projects can be tackled with little more than a couple of pairs of pliers, some cutters, and a cheap soldering iron.

But while the basic kit of tools for any job may be enough, there will always be those jobs that need more tools. Oh sure, sometimes you can — and should — make do with what you’ve got; I can’t count the number of times I’ve used an elastic band wrapped around the handles of a pair of needlenose pliers as an impromptu circuit board vise. But eventually, you’re going to come upon a situation where only the “real” tool will do, and substitutes need not apply.

As I look around my shop and my garage, I realize that I may have a problem with these “tactical tool” purchases. I’ve bought so many tools that I’ve used far fewer times than I thought I would, or perhaps even never used, that I’m beginning to wonder if I tackle projects just as an excuse to buy tools. Then again, some of my tactical purchases have ended up being far more useful than I ever intended, which has only reinforced my tendency toward tool collecting. So I thought I’d share a few of my experiences with tactical tools, and see how the community justifies tactical tool acquisitions.

Continue reading “Ask Hackaday: What’s Your “Tactical Tool” Threshold?”

Mat Boards Are Spendy, So DIY CNC Tool To The Rescue

Mats are flat pieces of paper-based material that fill the space between a frame and the art within. They perform a number of aesthetic and practical functions, and they can also be expensive to purchase. Making them by hand is an option, but it’s an exacting process. [wooddragon48] felt that a CNC solution would serve this need nicely, and began designing a DIY CNC tool to do exactly that.

One of the tricky parts about cutting mat boards is that cuts are at an angle, and there is really no tolerance for overcuts or any kind of visual blemish. CNC control would seem to offer a great solution to both the need for precisely straight cuts, as well as fine control over where cuts begin and end in a way that opens the door to complex designs that would be impractical to do by hand.

[wooddragon48]’s design has an angled cutter designed to plunge perfectly on demand, surrounded by a ring — similar to that on a router — which ensures the cutting tool is always consistently positioned with the material. It’s still in the design phase, but this is a type of tool that doesn’t yet exist so far as we can tell. The ability to CNC cut mat board, especially in complex designs, would be a huge timesaver.

Art and DIY CNC have a long history of happy intersection, as we have seen with a CNC router repurposed for string art, a CNC painting robot, and even an interactive abstract sculpture generator.

Hack Simple

Here at Hackaday, we definitely love to celebrate the hard hacks: the insane feats of reverse engineering, the physics-defying flights of fancy, or the abuse of cutting edge technology. But today I’d like to raise a rhetorical glass in tribute of the simple hacks. Because, to be perfectly honest, the vast majority of my hacks are simple hacks, and it’s probably the same for you too. And these often go unsung because, well, they’re simple. But that doesn’t mean that something simple can’t be helpful.

Case in point: an ESP8266 press-buttons device that we featured this week. It doesn’t do much. It’s main feature is that it connects to a home automation network over WiFi and enables you to flip three relays. Wires coming off the board are to be soldered to the not-yet-smart device in question, simply connected to each side of the button you’d like to press. In the example, a coffee machine was turned on and the “go” button pressed, automating one of the most essential kitchen rituals. While recording the podcast, I realized that I’ve built essentially this device and have it controlling our house’s heating furnace.

For the experienced hacker, there’s not much here. It’s a simple board design, the software heavily leverages ESPHome, so there’s not much work on that front either. But imagine that you lacked any of the wide-ranging skills that it takes to make such a device: PCB layout, ESP8266 software wrangling, or the nuances of designing with relays. You could just as easily build this device wrong as right. The startup costs are non-trivial.

Making a simple design like this available to the public isn’t a technical flex, and it’s not contributing to the cutting edge. But it just might be giving someone their first taste of DIY home automation, and a sweet taste of success. There’s not much easier than finding a switch and soldering on two wires, but if that’s the spark that pushes them on their path to greater hacks, that’s awesome. And even if it doesn’t, at least it’s another appliance under user control, connected to a private WiFi network rather than spying you out and phoning home to Big Toaster.

So here’s to the simple hacks!