Timeline of the universe. A representation of the evolution of the universe over 13.77 billion years. The far left depicts the earliest moment we can now probe, when a period of "inflation" produced a burst of exponential growth in the universe. (Size is depicted by the vertical extent of the grid in this graphic.) For the next several billion years, the expansion of the universe gradually slowed down as the matter in the universe pulled on itself via gravity. More recently, the expansion has begun to speed up again as the repulsive effects of dark energy have come to dominate the expansion of the universe. The afterglow light seen by WMAP was emitted about 375,000 years after inflation and has traversed the universe largely unimpeded since then. The conditions of earlier times are imprinted on this light; it also forms a backlight for later developments of the universe. (Credit: NASA)

ESA’s Euclid Space Telescope And The Quest For Dark Energy

July 31, 2023 by Maya Posch 30 Comments

Most of what humankind and other mammalian species on Earth experience of the Universe is primarily restricted to the part of the electromagnetic spectrum which our optical organs can register. Despite these limitations, we have found ways over the centuries which enable us to perceive the rest of the EM spectrum, to see both what is incredibly far away, and what is incredibly small, to constantly get a little bit closer to understanding what makes the Universe into what we can observe today, and what it may look like in the future.

An essential element of this effort are space telescopes, which gaze into the depths of the Universe with no limitations imposed by the Earth’s atmosphere, or human activity. Among the many uses of space telescopes, the investigation of the expansion of the Universe is perhaps the most fascinating, as this brings us ever closer to the answers to the most fundamental questions about not only its shape, but also to its future, which may include hitherto unknown types of matter and energy.

With the recently launched Euclid space telescope, another chapter is being opened in the saga on dark energy and matter, and their nature and effects on the Universe, as well as whether they exist at all. Yet how exactly do you use a space telescope to ferret out the potential effects of dark energy?

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Ask Hackaday: What’s The Deal With Humanoid Robots?

July 31, 2023 by Lewin Day 43 Comments

When the term ‘robot’ gets tossed around, our minds usually race to the image of a humanoid machine. These robots are a fixture in pop culture, and often held up as some sort of ideal form.

Yet, one might ask, why the fixation? While we are naturally obsessed with recreating robots in our own image, are these bipedal machines the perfect solution we imagine them to be?

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Automatic Transfer Switch Keeps Internet Online

July 31, 2023 by Bryan Cockfield 48 Comments

Living in a place where the electric service isn’t particularly reliable can be frustrating, whether that’s because of a lack of infrastructure, frequent storms, or rolling blackouts. An option for those living in these situations is a backup generator, often turned on and connected by an automatic transfer switch. These are necessary safety devices too; they keep power lines from being back-fed by the generators. But there are other reasons to use transfer switches as well as [Maarten] shows us with this automatic transfer switch meant to keep his computers and Internet powered up.

The device is fairly straightforward. A dual-pole, dual-throw relay is housed inside of an electrical junction box with two electrical plugs, each of which can be connected to a different circuit or power source in [Maarten]’s house. The relay coil is energized by the primary power supply, and when that power is lost the relay automatically changes over to the other power supply, which might be something like a battery backup system. [Maarten] was able to get a higher quality product by building it himself rather than spending a comparable amount of money on a cheap off-the-shelf product as well. Continue reading “Automatic Transfer Switch Keeps Internet Online” →

Hackaday Links: July 30, 2023

July 30, 2023 by Dan Maloney 14 Comments

A couple of weeks ago, we noted with interest that the space shuttle Endeavour (OV85) would be set up as a full-stack launch configuration display, complete with external fuel tank and solid rocket boosters. We predicted that this would result in some interesting engineering, not least of which will be making the entire 20-story stack safe from seismic activity. Looks like we were right on all counts, with this story about the foundation upon which the display will stand, which has been under construction for quite a while now. The base has six seismic isolators that support the 2.4-m thick slab of reinforced concrete that will serve as a perch for the full stack. The 1,800-ton slab will be able to move a meter or so from its resting position during earthquakes. Or perhaps more accurately, the foundation will allow Los Angeles to move as much as it wants while Endeavour rides it out.

If like us you’re worried that seismic loads are vastly different than the loads the spacecraft was actually designed for, relax — it turns out that the flight loads are far in excess of predicted loads from seismic stress. The plan is to build the booster stacks first — the aft skirts, which will support the entire stack, were just bolted in place — then lift the external tank in place between the boosters, and finally hoist the actual orbiter into place. After the stack is complete, the rest of the building will be built around it. We’re really looking forward to seeing some video on this project.

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Self-Hosted Chatbot Focuses On Privacy

July 30, 2023 by Bryan Cockfield 6 Comments

Large language models (LLMs) have been all the rage lately, assisting from all kinds of tasks from programming to devising Excel formulas to shortcutting school work. They’re also relatively easy to access for the most part, but as the old saying goes, if something on the Internet is free the real product is you (and your data). Luckily there are ways of hosting LLMs on your own to avoid your personal data getting harvested, as well as taking advantage of open-source solutions, but building these systems takes a little bit of effort. [Stephen] and a team from Mozilla walk us through this process and show us a number of options currently available.

Working from the ground up, the group first decides on hosting, which (unsurprisingly) involves using Mozilla hosting services. The choice of runtime environment was a little bit more challenging. The project was time constrained, so they looked at two options here: Hugging Face and llama.cpp. Eventually deciding to move forward with llama.cpp largely due to its ability to run on more consumer-oriented hardware (especially Apple silicon) and the fact that it doesn’t need a powerful GPU, the next task was to choose the model. Settling on the LLaMa model that Facebook recently open-sourced, this model works well with the runtime environment and is essentially the only one that does.

From there, the team at Mozilla wanted to make sure their chat bot would be able to provide other Mozilla employees with information more readily pertinent to their jobs, so they trained their model with some internal Mozilla data as well as other more generic information. This doesn’t mean the job is done, though, there are a number of other factors that went in to designing this system before it was finally complete. Even then, since they built this in a week it’s not perfect; there are some issues with non-permissive licensing of some of the components and many of the design choices may not have been ideal. It’s impressive what’s out there if you’re hosting your own system, though, and while this might be a little more advanced for a self-hosted project, take a look at some other more beginner-friendly projects you can try if you’re just starting out on the self-hosted path.

Fiber-Infused Ink Allows 3D-Printed Heart Muscle To Beat

July 29, 2023 by Maya Posch 7 Comments

Illustration from Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, Jun 19, 2013.

What makes a body’s organs into what they are is more than just a grouping of specialized cells. They also need to be oriented and attached to each other and scaffolding in order to create structures which can effectively perform the desired function. A good example here is the heart, which requires a large number of muscle cells to contract in unison in order for the heart component (like a ventricle) to effectively pump blood. This complication is what has so far complicated efforts to 3D print complex tissues and entire organs, but recently researchers have demonstrated a way to 3D print heart muscle which can contract when stimulated similarly to a human heart’s ventricle.

At the center of this technique lies a hydrogel that is infused with gelatin fibers. Using a previously developed Rotary Jet-Spinning technology that was reported on in 2016, a sheet of spun fibers was produced that were then cut up into micrometer-sized fibers which were dispersed into the hydrogel. After printing the desired structure – taking into account the fiber alignment – it was found that the cardiomyocytes (the cells responsible for carrying the contractile signal in the heart muscle) align along the thus laid out pattern, ultimately creating a cardiac muscle capable of organized contraction.

These findings come after many years of research into the topic, with e.g. Zihan Wang and colleagues in a 2021 paper reporting on the challenges remaining with 3D printing cardiac tissue, yet also the massive opportunities that this could provide. Although entire heart replacements (via therapeutic cloning with the patient’s own cells) might become possible too, more immediate applications would involve replacements for damaged cardiac muscle and other large structures of the heart.

Mechanical Pencil Solder Feeder Hack

July 29, 2023 by Chris Lott 29 Comments

Want a better way to feed solder, but want to do it on the quick and cheap? Well [ptkrf] has a solution for you in an old instructables post we stumbled upon recently. You might have, or can inexpensively buy, a mechanical pencil which has the feeder button on the side rather than on top, as usual. With the pencil in hand, [ptkrf] shows you the simple procedure for modifying the pencil into a solder feeder. You might need to experiment with different size pencils and solders to get a perfect match. Common mechanical pencils come in sizes to accommodate 0.5, 0.7, and 0.9 mm leads, but there are bigger and smaller ones available. Perhaps one of those really large drafting lead holders could be repurposed as a solder dispenser for the bigger jobs.

We discussed a 3D printed solder feeder a few days ago, but if you don’t have one, this may be a good way to go. Thanks to [iliis] for sending in this tip.