Demonstrating Gray Codes With Industrial Display

Many people base huge swaths of their lives on foundational philosophical texts, yet few have read them in their entirety. The one that springs to the forefront of many of our minds is The Art of Computer Programming by Donald Knuth. Full of many clever and outright revolutionary algorithms and new ways of thinking about how computers work, [Attoparsec] has been attempting to read this tome from cover to cover, and has found some interesting tidbits. One of those is the various algorithms around Gray Codes, and he built this device as a visual aid.

Gray Codes, otherwise known as reflected binary, is a way of ordering an arbitrarily large set of binary values so that only one bit changes between any two of them. The most common place these are utilized is in things like rotary encoders, where it provides better assurance that the position of a shaft is in a known location. To demonstrate this in a more visual way [Attoparsec] hooked up an industrial signal light, normally used for communicating the status of machinery in a factory, and then programmed it to display the various codes. A standard binary counter is used as a reference, and it can also display standard Gray Code as well as a number of other algorithms used for solving similar problems.

[Attoparsec] built this as an interactive display for the Open Sauce festival in San Francisco. To that end it needed to be fairly rugged, so he built it out of old industrial equipment, which is also a fitting theme for the light itself. There’s also a speed controller and an emergency stop button which also add to the motif. For a deeper dive on Gray Codes and their uses, take a look at this feature from a few years back.

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Venus Flytrap Takes Ride Through A Particle Accelerator

In the blue corner, we have the VENUS FLYTRAP! In the red corner, we have the underdog of the century, AN ENTIRE PARTICLE ACCELERATOR. Yes, you read that right. When you have a particle accelerator, it’s only second nature to throw anything you can into it. That’s why [Electron Impressions] put a poor fly-eating trap into their accelerator.

Chloride and potassium ions leaving cause osmotic pressure in neighboring cells

The match-up isn’t quite as arbitrary as it might seem at first. The flytrap’s main mechanism of trapping and digesting insects relies heavily on intracellular ion movement. Many cells along the inside of the trap have hair-activated calcium channels that respond to a fly landing on its surface. This ion movement then creates an action potential, which propagates along the entire surface, triggering closing. As the potential moves across different cells, other ions leave and create osmotic pressure. This pressure is what creates the mechanical movement.

Of course, this makes it no surprise when the plant finds itself under the ionizing radiation that every single head closes at once. While this is a cool demonstration, there is a slight side effect of killing every single cell by ripping apart the trap’s DNA.

Well, who would have guessed that the underdog accelerator would have won… Anyways, the DNA being ripped apart is far from ideal for repeatability. If you want to learn more about genetic features that SHOULD be repeated, then make sure to check out the development of open-source insulin!

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Low Self-Discharge, High-Voltage Supercapacitors Using Porous Carbon

Supercapacitors rely mostly on double-layer capacitance to bridge the divide between chemical batteries and traditional capacitors, but they come with a number of weaknesses. Paramount among these are their relatively low voltage of around 2.7 V before their electrolyte begins to decompose, as well as their relatively high rates of self-discharge. Here a new design using lignin-derived porous carbon electrodes and a fluorinated diluent was demonstrated by [Shichao Zhang] et al., as published in Carbon Research, that seems to address these issues.

Most notable are the relatively high voltage of 4 V, an energy density of 77 Wh/kg and a self-discharge rate that’s much slower than that of conventional supercapacitors. In comparison with these supercapacitors, these demonstrated versions are also superior in terms of recharge cycles with 90% of capacity remaining after 10,000 cycles, which together with their much higher energy density should prove to be quite useful.

This feat is accomplished by using lignin as the base for the carbon electrodes to make a highly porous surface, along with the new electrolyte formulation consisting of a lithium salt (LiBF4) dissolved in sulfolane with TTE as a non-solvating diluent. The idea of using lignin-derived carbon for such a purpose has previously been pitched by [Jia Liu] et al. in 2022 and [Zhihao Ding] in 2025, with this seemingly one of the first major applications we may be seeing.

Although the path towards commercialization from a lab-assembled prototype is a rough one, we may be seeing some of these improvements come to supercapacitors near you sooner rather than later.

Storing Solar Energy As Ice For Air Conditioning

Thermal energy storage is pretty great, as phase-change energy storage is very consistent with its energy output over time, unlike chemical batteries. You also get your pick from a wide range of materials that you can either heat up or cool down to store energy. Here, the selection is mostly dependent on how you wish to use that energy at a later date. [Hyperspace Pirate] is mostly interested in cooling down a house, on account of living in Florida.

As can be seen in the top image, the basic setup is pretty straightforward. PV solar power charges a battery until it’s fully charged. Then an MCU triggers a relay on the AC inverter, which then starts the cooling compressor on the water reservoir. This proceeds to phase change the water from a liquid into ice. The process can later be reversed, which will draw thermal energy out of the surrounding air and thus provide cooling.

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Replicating A Nuclear Event Detector For Fun And Probably Not Profit

Last year, we brought you a story about the BhangmeterV2, an internet-of-things nuclear war monitor. With a cold-war-era HSN-1000 nuclear event detector at its heart, it had one job: announce to everything else on the network than an EMP was inbound, hopefully with enough time to shut down electronics. We were shocked to find out that the HSN-1000 detector was still available at the time, but that time has now passed. Fortunately [Bigcrimping] has stepped up to replicate the now-unobtainable component at the heart of his build with his BHG-2000 Nuclear Event Detector — but he needs your help to finish the job. Continue reading “Replicating A Nuclear Event Detector For Fun And Probably Not Profit”

Seeing The World Through Animal Eyes

If you think about it, you can’t be sure that what you see for the color red, for example, is what anyone else in the world actually sees. All you can be sure of is that we’ve all been trained to identify whatever we do see as red just like everyone else. Now, think about animal vision. Most people know that dogs don’t see as many colors as we do. On the other hand, the birds and the bees can see into ultraviolet. What would the world look like with extra colors? That’s the question researchers want to answer with this system for duplicating different animals’ views of the world.

Of course, this would be easy if you were thinking about dogs or cats. They can’t see the difference between red and green, making them effectively colorblind by human standards. Researchers are using modified commercial cameras and sophisticated video processing to produce images that sense blue, green, red, and UV light. Then they modify the image based on knowledge of different animal photoreceptors.

We were somewhat surprised that the system didn’t pick up IR. As we know snakes, for example, can sense IR. You’d think more sophisticated animals would have better color vision, but that seems to be untrue. The mantis shrimp, for example, has 12-16 types of photoreceptors. Even male and female humans have different vision systems that make them see colors differently.

Maybe you need a photospectrometer. You wonder if animals dream in color, too.

Building A Class 100 Semiconductor Cleanroom Inside A Shed

Just your typical backyard cleanroom shed. (Credit: Dr. Semiconductor, YouTube)
Just your typical backyard cleanroom shed. (Credit: Dr. Semiconductor, YouTube)

Most people see that garden shed as little more than a place to store some gardening tools in, but if you’re like [Dr. Semiconductor], then what you see is a potential cleanroom for semiconductor manufacturing. As ridiculous as this may sound, the basic steps behind the different levels of cleanrooms work just as well for a multi-million dollar fab as they do for for a basic shed.

Key to everything is HEPA filtration along with positive pressure, to constantly push clean air into the cleanroom, while preventing dirty air from flowing in. The shed was also split into two sections, the first room once you enter it being the the gowning room. This is where you change into cleanroom gear before you transition into the cleanroom.

In addition to the flame-resistant drywalls, a water-based epoxy coating was applied to the insides of the cleanroom walls to make it smooth and free of debris. The HEPA filtration system constantly filters the shed’s air along with some fresh outside air, while an airconditioning unit ensures that the temperature remains constant.

The measured >0.5 µm particle contamination inside the shed turned out to be enough for a FED STD 209E equivalent of Class 100, which is ISO 5 class with a maximum of 3,520 particles/m3. For comparison, room air is ISO 9 with max 35,200,000 particles/m3. At ISO 5 it’s good enough to do some semiconductor R&D laboratory things, which is what [Dr. Semiconductor]’s channel is – shockingly – about.

Thanks to [Thayer] for the tip.

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