Fictional Computers: The Three Body Problem

April 5, 2024 by Al Williams 54 Comments

If you intend to see the Netflix series “The Three Body Problem” or you want to read the Hugo-winning story from Chinese author [Cixin Liu], then you should probably bookmark this post and stop reading immediately. There will be some mild spoilers. You have been warned.

While the show does have some moments that will make your science brain cringe, there is one scene that shows a computer that could actually be built. Would it be practical? Probably not in real life, but in the context provided by the show, it was perfectly feasible. It could have, however, been done a little better, but the idea was — like many great ideas — both deceptively simple and amazingly profound. The computer was made of human beings. I’m not talking like Dune’s mentats — humans with super brains augmented by drugs or technology. This is something very different.

Background

This is your last chance. There are spoilers ahead, although I’ll try to leave out as much as I can. In the story, top scientists receive a mysterious headset that allows them to experience totally immersive holodeck-style virtual reality. When they put the headset on, they are in what appears to be a game. The game puts you in a historical location — the court of Henry VIII or Ghengis Kahn. However, this Earth has three suns. The planet is sometimes in a nicely habitable zone and sometimes is not. The periods when the planet is uninhabitable might have everything bursting into flames or freezing, or there might not be sufficient gravity to hold them on the planet’s surface. (Although I’ll admit, I found that one hard to grasp.)

Apparently, the inhabitants of this quasi-Earth can hibernate through the “chaotic eras” and wait for the next “stable era” that lasts a long time. The problem, as you probably know, is that there is no general closed-form solution for the three-body problem. Of course, there are approximations and special cases, but it isn’t easy to make long-term predictions about the state of three bodies, even with modern computers.

Continue reading “Fictional Computers: The Three Body Problem” →

Where Graph Theory Meets The Road: The Algorithms Behind Route Planning

April 4, 2024 by Maya Posch 35 Comments

Back in the hazy olden days of the pre-2000s, navigating between two locations generally required someone to whip out a paper map and painstakingly figure out the most optimal route between those depending on the chosen methods of transport. For today’s generations no such contrivances are required, with technology having obliterated even the a need to splurge good money on a GPS navigation device and annual map updates.

These days, you get out a computing device, open Google Maps or equivalent, ask it how you should travel somewhere, and most of the time the provided route will be the correct one, including the fine details such as train platform and departure times. Yet how does all of this seemingly magical route planning technology work? It’s often assumed that Dijkstra’s algorithm, or the A* graph traversal algorithm is used, but the reality is that although these pure graph theory algorithms are decidedly influential, they cannot be applied verbatim to the reality of graph traversal between destinations in the physical world.

Continue reading “Where Graph Theory Meets The Road: The Algorithms Behind Route Planning” →

Amazon’s ‘Just Walk Out’ Shopping Is Out, Moves To Dash Carts At Its Grocery Stores

April 4, 2024 by Maya Posch 60 Comments

After a few years of Amazon promoting a grocery shopping experience without checkout lines and frustrating self-checkout experiences, it is now ditching its Just Walk Out technology. Conceptualized as a store where you can walk in, grab the items you need and walk out with said items automatically charged to your registered payment method, it never really caught much traction. More recently it was revealed that the technology wasn’t even as automated as portrayed, with human workers handling much of the tedium behind the scenes. This despite claims made by Amazon that it was all powered by deep machine learning and generative AI.

An Amazon Dash Cart's user interface, with scanner and display. (Credit: Amazon) — An Amazon Dash Cart’s user interface, with scanner and display. (Credit: Amazon)

Instead of plastering the ceilings of stores full with cameras, it seems that Amazon instead wishes to focus on smart shopping carts that can keep track of what has been put inside them. These so-called Dash Carts are equipped with cameras and other sensors to scan barcodes on items, as well as weigh unlabeled items (like fruit), making them into somewhat of a merging of scales at the vegetable and fruit section of stores today, and the scanning tools offered at some grocery stores to help with self-checkout.

As the main problem with the Just Walk Out technology was that it required constant (700 out of 1,000 sales in 2022) human interaction, it will be interesting to see whether the return to a more traditional self-service and self-checkout model (albeit with special Dash Lanes) may speed things along. Even so, as Gizmodo notes, Amazon will still keep the Just Walk Out technology running across locations in the UK and elsewhere. Either this means the tech isn’t fully dead yet, or we will see a revival at some point in time.

PCB Design Review: Tinysparrow, A Module For CAN Hacking Needs

April 3, 2024 by Arya Voronova 22 Comments

I enjoy seeing modules that can make designing other devices easier, and when I did a call for design reviews, [enp6s0] has submitted one such board to us. It’s a module called TinySparrow (GitHub), that helps you build your own vehicle ECUs and any other CAN-enabled things. With a microcontroller, plenty of GPIOs, a linear regulator and a CAN transceiver already onboard, this board has more than enough kick for anyone in hobbyist-range automotive space – and it’s surprisingly tiny!

You could build a lot of things around this module – a CAN bus analyzer or sniffer, a custom peripheral for car dashes, or even a full-blown ECU. You can even design any hardware for a robot or a piece of industrial technology that uses CAN for its backbone – we’ve all seen a few of those! It’s a great board, but it uses six layers. We’ll see if we can do something about that here.

Modules like TinySparrow will make your PCBs cheaper while ordering, too! Thanks to the carefully routed microcontroller and the CAN transmitter, whatever board you design around this chip definitely wouldn’t need six layers like this one does – and, unlike designing your own board, you can use someone’s well-tested and tailored libraries and reference circuits!

With TinySparrow, you save a lot of time, effort and money whenever you want to design a car or industrial accessory. After looking at the board files, my proposal for helping today’s board is – like last time – to make its production cheaper, so that more people can get this board into their hands if the creator ever does try and manufacture it. I also have some tips to make future improvements on this design easier, and make it more friendly for its userbase.

Continue reading “PCB Design Review: Tinysparrow, A Module For CAN Hacking Needs” →

Space Mirrors: Dreams Of Turning The Night Into Day Around The Clock

April 3, 2024 by Maya Posch 28 Comments

Recently, a company by former SpaceX employee Ben Nowack – called Reflect Orbital – announced that it is now ready to put gigantic mirrors in space to reflect sunshine at ground-based solar farms. This is an idea that’s been around for a hundred years already, both for purposes of defeating the night through reflecting sunshine onto the surface, as well as to reject the same sunshine and reduce the surface temperature. The central question here is perhaps what the effect would be of adding or subtracting (or both) of solar irradiation on such a large scale as suggested?

We know the effect of light pollution from e.g. cities and street lighting already, which suggests that light pollution is a strongly negative factor for the survival of many species. Meanwhile a reduction in sunshine is already a part of the seasons of Autumn and Winter. Undeniable is that the Sun’s rays are essential to life on Earth, while the day-night cycle (as well as the seasons) created by the Earth’s rotation form an integral part of everything from sleep- and hibernation cycles, to the reproduction of countless species of plants, insects, mammals and everyone’s favorite feathered theropods.

With these effects and the gigantic financial investments required in mind, is there any point to space-based mirrors?

Continue reading “Space Mirrors: Dreams Of Turning The Night Into Day Around The Clock” →

Mining And Refining: Tungsten

April 2, 2024 by Dan Maloney 16 Comments

Our metallurgical history is a little bit like a game of Rock, Paper, Scissors, only without the paper; we’re always looking for something hard enough to cut whatever the current hardest metal is. We started with copper, the first metal to be mined and refined. But then we needed something to cut copper, so we ended up with alloys like bronze, which demanded harder metals like iron, and eventually this arms race of cutting led us to steel, the king of metals.

But even a king needs someone to keep him in check, and while steel can be used to make tools hard enough to cut itself, there’s something even better for the job: tungsten, or more specifically tungsten carbide. We produced almost 120,000 tonnes of tungsten in 2022, much of which was directed to the manufacture of tungsten carbide tooling. Tungsten has the highest melting point known, 3,422 °C, and is an extremely dense, hard, and tough metal. Its properties make it an indispensible industrial metal, and it’s next up in our “Mining and Refining” series.

Continue reading “Mining And Refining: Tungsten” →

Japan’s First Commercial Rocket Debuts With A Bang

March 27, 2024 by Tom Nardi 11 Comments

Though it suffered through decades of naysayers, these days you’d be hard pressed to find anyone who would still argue that the commercialization of space has been anything but a resounding success for the United States. SpaceX has completely disrupted what was a stagnant industry — of the 108 US rocket launches in 2023, 98 of them were performed by the Falcon 9. Even the smaller players, such as Rocket Lab and Blue Origin, are innovating and bringing new technologies to market at a rate which the legacy aerospace companies haven’t been able to achieve since the Space Race.

So it’s no surprise that other countries are looking to replicate that success. Japan in particular has been following NASA’s playbook by offering lucrative space contracts to major domestic tech companies such as Mitsubishi, Honda, NEC, Toyota, Canon, Kyocera, and Sumitomo. Over the last several years this has resulted in the development of a number spacecraft and missions, such as the Hakuto-R Moon lander. It’s also laid the groundwork for exciting future projects, like the crewed lunar rover Toyota and Honda are jointly developing for the Artemis program.

But so far there’s been a crucial element missing from Japan’s commercial space aspirations, an orbital booster rocket. While the country has state-funded launch vehicles such as the H-IIA and H3 rockets, they come with the usual bureaucracy one would expect from a government program. In comparison, a privately developed and operated booster holds the promise of reduced costs and a higher launch cadence, especially if there are multiple competing vehicles on the market.

With the recent test flight of Space One’s KAIROS rocket, that final piece of the puzzle may finally be falling into place. While the launch unfortunately failed shortly after liftoff, the fact that the private rocket was able to get off the ground — literally and figuratively — is a promising sign of what’s to come.

Continue reading “Japan’s First Commercial Rocket Debuts With A Bang” →