The Eyes Have It: Stare Down Your Lighting

March 6, 2023 by 8 Comments

You know how you can feel when someone is looking at you? Thanks to a person detector, [Michael Rigsby’s] little robotic light switch also knows when you are looking at it. As you can see in the video below, when it notices you are looking at it, it lights up an LED. If you continue to gaze at it, it will turn to stare back at you. Keep staring it down and it will toggle the state of a remote control light switch.

This all works because of the person sensor module by Useful Sensors. The little module has a camera and face detection built into it. It doesn’t draw much power at 150 milliwatts. It can sense faces, including where they are and how many people are looking.

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Your Phone Is A 200X Microscope — Sort Of

March 6, 2023 by 19 Comments

[A. Cemal Ekin] over on PetaPixel reviewed the Apexel 200X LED Microscope Lens. The relatively inexpensive accessory promises to transform your cell phone camera into a microscope. Of course, lenses that strap over your phone’s camera lens aren’t exactly a new idea, but this one looks a little more substantial than the usual piece of plastic in a spring-loaded clip. Does it work? You should read [Cemal’s] post for the details, but the answer — as you might have expected — is yes and no.

On the yes side, you can get some pretty neat photomicrographs from the adapter. On the negative side, your phone isn’t made to accommodate microscope samples. It also isn’t made to stay stable at 200X.

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MEMS Teardown And Macroscopic Models

March 6, 2023 by 18 Comments

There is a bit of a paradox when it comes to miniaturization. When electronics replaced mechanical devices, it was often the case that the electronic version was smaller. When transistors and, later, ICs, came around, things got smaller still. However, as things shrink to microscopic scales, transistors don’t work well, and you often find — full circle — mechanical devices. [Breaking Taps] has an investigation of a MEMS chip. MEMS is short for Micro Electromechanical Systems, which operate in a decidedly mechanical way. You can see the video, which has some gorgeous electron microscopy, below. The best part, though, is the 3D-printed macroscale mechanisms that let you see how the pieces work.

Decapsulating the MPU-6050 was challenging. We usually mill a cavity on the top of an IC and use fuming nitric on a hot plate (under a fume hood) to remove the remaining epoxy. However, the construction of these chips has two pieces of silicon sandwiched together, so you need to fully expose the die to split them apart, so our usual method might not work so well. Splitting them open, though, damaged parts of the chip, so the video shows a composite of several devices.

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What Does An Electron Look Like?

March 6, 2023 by 23 Comments

In school, you probably learned that an atom was like a little solar system with the nucleus as the sun and electrons as the planets. The problem is, as [The Action Lab] points out, the math tells us that if this simplistic model was accurate, matter would be volatile. According to the video you can see below, the right way to think about it is as a standing wave.

What does that mean? The video shows a very interesting demonstrator that shows how that works. You can actually see the standing waves in a metal ring. This is an analog — still not perfect — for the workings of an atom. An input frequency causes the ring to vibrate, and at specific vibration frequencies, a standing wave develops in the ring.

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What’s Going To Happen To Legacy Broadcast Bands When The Lights Go Out?

March 6, 2023 by 215 Comments

Our smartphones have become our constant companions over the last decade, and it’s often said that they have been such a success because they’ve absorbed the features of so many of the other devices we used to carry. PDA? Check. Pager? Check. Flashlight? Check. Camera? Check. MP3 player? Of course, and the list goes on. But alongside all that portable tech there’s a wider effect on less portable technology, and it’s one that even has a social aspect to it as well. In simple terms, there’s a generational divide that the smartphone has brought into focus, between older people who consume media in ways born in the analogue age, and younger people for whom their media experience is customized and definitely non-linear.

The Kids Just Don’t Listen To The Radio Any More

A 1957 American family watching TV
We’re guessing this is no longer a scene played out in many homes. Evert F. Baumgardner, Public domain.

The effect of this has been to see a slow erosion of the once-mighty reach of radio and TV broadcasters, and with that loss of listenership has come less of a need for the older technologies they relied on. Which leaves a fascinating question here at Hackaday, what is going to happen to all that spectrum? Indeed, there’s a deeper question behind all that, is lower frequency spectrum even that valuable any more?

In the old days, we had analogue TV in several-MHz-wide channels spread across a large part of the UHF bands and some smaller chunks of VHF. Among that we had 20 MHz of FM broadcasting around the 100 MHz mark, and disregarding shortwave, then a MHz of AM down around 1 MHz. Europeans got a bonus band down there too: we’ve got Long Wave, over 100 kHz of AM goodness roughly centered around 200 kHz.

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A yellow computer with a black keyboard and a small monochrome LCD screen

Low Power Challenge: The PotatoP Runs Lisp For Months Without Recharging

March 6, 2023 by 54 Comments

A common complaint among laptop users is that while battery technology has vastly improved over the past decades, a simulltaneous shrink in form factors has meant that a typical laptop today doesn’t last much longer on a battery charge than one from the early 2000s. But it doesn’t have to be that way, as [Andreas Eriksen] demonstrates with his entry for the Low Power Challenge. The PotatoP is a portable computer that should be able to run for about two years on a single battery charge, and can be topped up through an integrated solar panel.

Granted, it doesn’t have the processing power of even the cheapest laptop you can buy today, but it’s perfectly fine for [Andreas]’s use case. He’s a Lisp hacker, and a Sparkfun RedBoard Artemis can run uLisp just fine on its 48 MHz Cortex-M4F processor. The operating environment is very basic though, even requiring [Andreas] to write his own text editor, called Typo, to give him editing luxuries like backspace functionality and a movable cursor.

The Artemis board is very power-efficient by itself – typical power consumption is less than 1 mA. [Andreas] added a simple monochrome black-and-white LCD screen capable of displaying 53 columns of text, plus an SD card reader for data storage, and designed a sleek 3D-printed case to hold everything together. When running a typical piece of code, the entire system uses around 2.5 mA, which translates to about 125 days of continuous run-time on the beefy 12000 mAh lithium battery. Add a bit of solar power, plus a more realistic eight-hour working day, and the two year runtime estimated by [Andreas] appears entirely reasonable.

This has to be one of the most power-efficient portables we’ve ever seen, and one running Lisp at that. Despite its age, Lisp keeps popping up in interesting custom computers like the Lisperati1000 cyberdeck and The Lisp Badge.

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The Future Of RISC-V And The VisionFive 2 Single Board Computer

March 6, 2023 by 47 Comments

We’ve been following the open, royalty-free RISC-V ISA for a while. At first we read the specs, and then we saw RISC-V cores in microcontrollers, but now there’s a new board that offers enough processing power at a low enough price point to really be interesting in a single board computer. The VisionFive 2 ran a successful Kickstarter back in September 2022, and I’ve finally received a unit with 8 GB of ram. And it works! The JH7110 won’t outperform a modern desktop, or even a Raspberry Pi 4, but it’s good enough to run a desktop environment, browse the web, and test software.

And that’s sort of a big deal, because the RISC-V architecture is starting to show up in lots of places. The challenge has been getting real hardware that’s powerful enough to run Linux and compile software on, that doesn’t cost an arm and a leg. If ARM is an alternative architecture, then RISC-V is still an experimental one, and that is an issue when trying to use the VF2. That’s a theme we’ll repeat a few times, but the thing to remember here is that getting more devices in the wild is the first step to fixing things. Continue reading “The Future Of RISC-V And The VisionFive 2 Single Board Computer” →