Physical Neural Network Can Be Trained Like A Digital One

July 20, 2023 by 11 Comments

Here’s an unusual concept: a computer-guided mechanical neural network (video, embedded below.) Why would one want a mechanical neural network? It’s essentially a tool to explore what it would take to make physical materials work in nonstandard ways. The main part is a lattice of interlinked mechanical components. When one applies a certain force in a certain direction on one end, it causes the lattice to deform in a non-intuitive way on the other end.

To make this happen, individual mechanical elements  in the lattice need to have their compliance carefully tuned under the guidance of a computer system. The mechanisms shown can be adjusted on demand while force is applied and cameras monitor the results.

This feedback loop allows researchers to use the same techniques for training neural networks that are used in machine learning applications. Ultimately, a lattice can be configured in such a way that when side A is pressed like this, side B moves like that.

We’ve seen compliant structures that move in unexpected ways before, and they are always fascinating. One example is this 3D-printed door latch that translates a twisting motion into a linear one. Research into physical neural networks seems like it might open the door to more complex systems, or provide insights into metamaterial design.

You can watch the video below just under the page break, or if you prefer, skip the intro and jump straight into How It Works at [2:32].

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Smart Powermeter Uses E-Paper Display

July 20, 2023 by 17 Comments

In most places around the world, electricity is getting ever more expensive. Cutting back on your usage is one of the easier ways to escape this pain. This smart powermeter from [JGAguagdo] may prove a useful tool to achieve that goal.

The project uses an ESP32-S2 as the brains of the operation. It’s capable of reading up to six current-transformer clamps for measuring current draw in AC devices. It also features an embedded BMP280 temperature and air pressure sensor. Live data is displayed on a 2.9-inch e-Paper display, making it clear and easy to read under normal lighting conditions. By default, it’s set up to display graphs of power usage both over the last 24 hours, and the last ten days. It can even be set up with the prevailing energy rates in your area to display a realistic figure for what you’ll pay for your daily usage.

It can even be set up to work with Home Assistant for more logging and control options. We can imagine that, with a little work, you could even do some fancy plotting of energy use versus temperature to determine the performance and cost of your home HVAC setup.

If you want one with a minimum of fuss, you can score one on Tindie. Alternatively, design files are available on GitHub, too. We’ve featured some other great power meters over the years, and if you’re cooking up your own smart designs, don’t hesitate to let us know!

Game Boy-Style Camera For Playdate

July 20, 2023 by No comments

The Game Boy Camera, while perhaps not the most technologically advanced piece of equipment, left a huge mark on video game and electronics culture. The grayscale photographs are still highly prized, and there are an untold number of projects which interface with original hardware to download authentic Game Boy Camera pictures to modern computers. There are others that look to recreate the feel and style of these images, and the latest comes to us on a Game Boy-like platform as well, the Playdate.

[t0mg] is the creator of this project, utilizing a OV7670 camera module sending data to a Teensy 4.1 which interfaces with the Playdate via USB. The images recorded on the Playdate are 1-bit, slightly different than the 2-bit images the Game Boy Camera was capable of. The case of the camera also physically matches up well with the small console, using magnets to secure it to the device either in normal camera mode, in reverse for selfie mode, and can also support the console in “cover” mode as a way of storing the console to protect the screen. A companion application needs to run on the Playdate to get this all up and running, but with that and a battery plenty of retro-style images are ready to be captured.

All of the source for this project is available on the project’s GitHub page for anyone ready to experience some nostalgia or just experiment with a small camera like this. It’s a clean build that takes advantage of the Playdate’s open-source nature, through which we’ve seen the console turned into a typewriter and inspire other builds like this one-off handheld with a crank-style controller.

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TV Typewriter Remembered

July 20, 2023 by 23 Comments

With the recent passing of Don Lancaster, I took a minute to reflect on how far things have come in a pretty short period of time. If you somehow acquired a computer in the early 1970s, it was probably some discarded DEC, HP, or Data General machine. A few people built their own, but that was a stout project with no microprocessor chips readily available. When machines like the Mark-8 and, more famously, the Altair appeared, the number of people with a “home computer” swelled — relatively speaking — and it left a major problem: What kind of input/output device could you use?

An ad from Kilobaud offered you a ready-to-go, surely refurbished, ASR33 for $840

At work, you might have TeleType. Most of those were leased, and the price tag of a new one was somewhere around $1,000. Remember, too, that $1,000 in 1975 was a small fortune. Really lucky people had video terminals, but those were often well over $1,500, although Lear Siegler introduced one at the $1,000 price, and it became wildly successful. Snagging a used terminal was not very likely, and surplus TeleType equipment was likely of the 5-bit Baudot variety — not unusable, but not the terminal you really wanted.

A lot of the cost of a video terminal was the screen. Yet nearly everyone had a TV, and used TVs have always been fairly cheap, too. That’s where Don Lancaster came in. His TV Typewriter Cookbook was the bible for homebrew video displays. The design influenced the Apple 1 computer and spawned a successful kit for a company known as Southwest Technical Products. For around $300 or so, you could have a terminal that uses your TV for output. Continue reading “TV Typewriter Remembered” →

Open Source OLED Nametag Is Full Of Features

July 20, 2023 by 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.

PCIe For Hackers: An M.2 Card Journey

July 20, 2023 by 22 Comments

I’ve designed a few M.2 adapters for my own and my friends’ use, and having found those designs online, people have asked me for custom-made adapters. One of these requests is quite specific – an adapter that adds one more PCIe link to an E-key M.2 slot, the kind of slot you will see used in laptops for WiFi cards.

See, the M.2 specification allows two separate PCIe links connected to the E-key slot; however, no WiFi cards use this apart from some really old WiGig-capable ones, and manufacturers have long given up on connecting a second link. Nevertheless, there are some cards like the Google Coral M.2 E-key dual AI accelerator and the recently announced uSDR, that do indeed require the second link – otherwise, only half of their capacity is available.

It’s not clear why both Google and WaveletSDR designed for a dual-link E-key socket, since those are a rare occurrence; for the Google card, there are plenty of people complaining that the board they bought just doesn’t fully work. In theory, all you need to do to help such a situation, is getting a second PCIe link from somewhere, then wiring it up to the socket – and a perfect way to do it is to get a PCIe switch chip. You will lose out on some bandwidth because the uplink PCIe connection of the switch can only go so fast; for things like this AI accelerator, it’s not much of a problem since the main point is to get the second device accessible. For the aforementioned SDR, it might turn out useless, or you might win some but lose some – can’t know until you try! Continue reading “PCIe For Hackers: An M.2 Card Journey” →

PCjr WebServer Hits 2500 Hours Uptime

July 20, 2023 by 23 Comments

When [Mike] fired up his PCjr webserver back in March, he probably wasn’t expecting it to go viral. 2640 hours later, here we are! Not only has his machine run continuously for over 110 days, it also is surviving a global hug of death. All of this is thanks to some very special software.

We see lots of old machines here on Hackaday. We also see lots of minimal web servers. But we don’t see many that can run for thousands of hours, offering up to 8 simultaneous connections. Curious if jr is still up? Check brutmanlabs.org. The whole website is hosted on the 40-year-old machine. If you want to be a bit more kind, here’s a direct link to the text-only status page. While many of those hours were idle, currently lots of folks are hitting that little V20 CPU, so please give it a few seconds to respond.

The PCjr has a few upgrades — the aforementioned V20 CPU upgrade, a jrIDE sidecar, and a memory upgrade to 736 kB to name a few.  Ethernet connectivity is via a Xircom parallel port adapter – which is circa 1993.  The operating system is IBM PC DOS 5.02. One thing to note is that all these upgrades were possible back in the mid-1980’s when the PCjr was still current.  [Mike] could run the system with an MFM hard drive, an ISA ethernet card (via an adapter), and use the original CRT monitor. Older DOS versions would work too — though partition sizes would be limited. The “modern” conveniences are just to keep from wearing out vintage hardware which is quickly becoming rare.

The real glue that holds this all together is [Mike’s] own software: mTCP. mTCP is a full set of tools for running internet applications on systems running MS-DOS or a compatible OS. We’ve seen quite a few mTCP projects over the years.  [Mike] has worked tirelessly testing the software, ensuring that it is stable and reliable.

Software is never perfect though – one thing [Mike] didn’t implement is a log roller. Since he has logging turned on, the PCjr was slowly filling up its hard drive. Once the drive was full, mTCP would perform an orderly shutdown — but the uptime will be reset.  [Mike] was able to go in and switch off logging with  DOS’s DEBUG command. A live patch is not the way one would normally update software – but the fact that he was able to do it shows how deep [Mike’s] knowledge of the software goes.

[Mike] has even provided a live stream recording of the little PCjr handling requests from all over the globe.

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