Chernobyl’s Robots, Or The Hackathon From Hell

When the Chernobyl Nuclear Power Plant’s #4 reactor experienced an extreme criticality event on that infamous day in 1986, the resulting steam explosion and lack of any kind of containment building meant that parts of the core were scattered throughout the site. In an extensive update to the original 2023 video, the [Chornobyl Family] covers the mad scramble to design robots to perform on-the-ground measurements, and ultimately remove all this debris for safe disposal.

The TR-1A, an early debris removal robot. (Source: Chornobyl Family, YouTube)
The TR-1A, an early debris removal robot. (Source: Chornobyl Family, YouTube)

This essentially took the form of a hackathon, involving teams from all over the USSR and allied nations, creating the most diverse range of robots that 1980s Soviet technology and later Western technology could muster.

Many of these robots didn’t perform very well, or at all, mostly due to the bypassing of any kind of testing before deployment. Especially at the beginning of the clean-up the robots were being pushed into the high-radiation zones as soon as they were finished, with not only mechanical issues being a problem, but also with e.g. inaccurate radiation measurements by the RR-1 robot, that overstated measurements by more than a factor of ten. Meanwhile the RR-2 and RR-3 were too top-heavy and after deployment by helicopter simply tipped over. Eventually manual measurements proved to be faster and safer.

Early debris removal robots like the TR-1A were rather simplistic, with successive generations of robots over the next weeks and months improving on it. The use of a combustion engine instead of batteries provided to be a boon, as combustion engines are far less affected by radiation.

The BAER Beloyarets used an airport cart as the basis, with its electronics relying on vacuum tube technology and relays, with an internal combustion engine. This proved to be one of the most reliable designs and it’s been largely preserved on display in the Chornobyl Exclusion Zone, with many others of these robots also being on display around the nuclear plant or in the city of Chornobyl.

Overall an absolutely dizzying number of robotic designs were invented on the spot, adapted from existing designs or repurposed for operation in a high-radiation zone. Eventually bulldozer designs like the STR-1 helped to push radioactive debris off the roofs into containers, massively reducing the radioactive contamination of the area.

The fact that following #4’s RUD the other three RBMK units were able to keep operating safely without risks to its operators, and with the zone now safe for tourists, is a real testament to the success of the worst hackathon imaginable. Many of the lessons learned are relevant today, including during the decommissioning of Fukushima Daiichi’s melted-down cores.

Continue reading “Chernobyl’s Robots, Or The Hackathon From Hell”

A diagram of a neutron generator is shown in the top portion of the image, with the physical version below.

A Benchtop Neutron Generator For The Home Reactor

There are a surprising number of experiments an amateur nuclear physicist can perform, from making a Geiger counter to fusing hydrogen atoms in a fusor. One project which we haven’t seen before is a neutron generator, such as the benchtop neutron generator made by [Rapp Instruments] (translated).

This particular generator takes a feedstock of pure deuterium, which it ionizes and accelerates into a titanium target. The first deuterium nuclei to hit the target react with it to form titanium deuteride, immobilizing them until more ions strike them and they undergo nuclear fusion. The fusion reaction mostly forms helium-4, but sometimes forms helium-3 and a free neutron, which is radiated away. The radiated neutrons are slowed down by a block of high-density polyethylene, and a portion of them strike a silver or indium foil wrapped around a Geiger counter tube. The neutrons activate the silver or indium, and the Geiger counter detects the resultant increase in radioactivity.

The design is a linear particle accelerator built inside an evacuated glass tube. It uses two high-voltage power supplies: a 20 kV supply which ionizes the deuterium gas fed into the tube, and a 100 kV supply which accelerates ions emitted from the source into the target. The target itself is surrounded by a cup-shaped electrode to capture secondary electrons emitted during impact. To prevent arcing, the tube needs to be at a very low pressure, reached by extensive use of an oil diffusion pump.

Radioactivity measurements of the silver and indium foils showed that the generator did work; when irradiating the silver foil for five minutes, it generated 175 counts per second after the neutron source was turned off. Plotting the count rate versus time suggested that a mixture of two silver isotopes was being generated, Ag-110 and Ag-108, based on their half-lives. Irradiation of indium produced a similar exponential decay in radiation.

We recommend checking out the rest of the site; it’s a gold mine of projects, such as this mass spectrometer. For more background on neutron generators, we’ve covered their theory and some of the more common varieties.

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!

Continue reading “Venus Flytrap Takes Ride Through A Particle Accelerator”

The Hottest Spark Plugs Were Actually Radioactive

In the middle of the 20th century, the atom was all the rage. Radiation was the shiny new solution to everything while being similarly poorly understood by the general public and a great deal of those working with it.

Against this backdrop, Firestone Tire and Rubber Company decided to sprinkle some radioactive magic into spark plugs. There was some science behind the silliness, but it turns out there are a number of good reasons we’re not using nuke plugs under the hood of cars to this day.

Continue reading “The Hottest Spark Plugs Were Actually Radioactive”

Meter Mods Make Radioactive Prospecting More Enjoyable

While we often get a detailed backstory of the projects we cover here at Hackaday, sometimes the genesis of a build is a bit of a mystery. Take [maurycyz]’s radiation survey meter modifications, for instance; we’re not sure why such a thing is needed, but we’re pretty glad we stumbled across it.

To be fair, [maurycyz] does give us a hint of what’s going on here by choosing the classic Ludlum Model 3 to modify. Built like a battleship, these meters would be great for field prospecting except that the standard G-M tube isn’t sensitive to gamma rays, the only kind of radiation likely not to be attenuated by soil. A better choice is a scintillation tube, but those greatly increase the background readings, making it hard to tease a signal from the noise.

To get around this problem and make rockhounding a little more enjoyable, [maurycyz] added a little digital magic to the mostly analog Ludlum. An AVR128 microcontroller taps into the stream of events the meter measures via the scintillation tube, and a little code subtracts the background radiation from the current count rate, translating the difference into an audible tone. This keeps [maurycyz]’s eyes on the rocks rather than on the meter needle, and makes it easier to find weakly radioactive or deeply buried specimens.

If you’re not ready to make the leap to a commercial survey meter, or if you just want to roll your own, we’ve got plenty of examples to choose from, from minimalist to cyberpunkish.

A piece of perovskite crystal

Perovskite Solar Cell Crystals See The Invisible

A new kind of ‘camera’ is poking at the invisible world of the human body – and it’s made from the same weird crystals that once shook up solar energy. Researchers at Northwestern University and Soochow University have built the first perovskite-based gamma-ray detector that actually works for nuclear medicine imaging, like SPECT scans. This hack is unusual because it takes a once-experimental lab material and shows it can replace multimillion-dollar detectors in real-world hospitals.

Current medical scanners rely on CZT or NaI detectors. CZT is pricey and cracks like ice on a frozen lake. NaI is cheaper, but fuzzy – like photographing a cat through steamed-up glass. Perovskites, however, are easier to grow, cheaper to process, and now proven to detect single photons with record-breaking precision. The team pixelated their crystal like a smartphone camera sensor and pulled crisp 3D images out of faint radiation traces. The payoff: sharper scans, lower radiation doses, and tech that could spread beyond rich clinics.

Perovskite was once typecast as a ‘solar cell wonder,’ but now it’s mutating into a disruptive medical eye. A hack in the truest sense: re-purposing physics for life-saving clarity.

Food Irradiation Is Not As Bad As It Sounds

Radiation is a bad thing that we don’t want to be exposed to, or so the conventional wisdom goes. We’re most familiar with it in the context of industrial risks and the stories of nuclear disasters that threaten entire cities and contaminate local food chains. It’s certainly not something you’d want anywhere near your dinner, right?

You might then be surprised to find that a great deal of research has been conducted into the process of food irradiation. It’s actually intended to ensure food is safer for human consumption, and has become widely used around the world.

Continue reading “Food Irradiation Is Not As Bad As It Sounds”