One Method For Removing Future Space Junk

March 22, 2023 by Bryan Cockfield 18 Comments

When sending satellites into space, the idea is to place them into as stable an orbit as possible in order to maximize both the time the satellite is useful and the economics of sending it there in the first place. This tends to become rather untenable as the amount of space junk continues to pile up for all but the lowest of orbits, but a team at Brown University recently tested a satellite that might help solve this problem, at least for future satellite deployments.

The main test of this satellite was its drag sail, which increases its atmospheric drag significantly and reduces its spaceflight time to around five years. This might make it seem like a problem from an economics standpoint, as it’s quite expensive to build satellites and launch them into space, but this satellite solves these problems by being both extremely small to minimize launch costs, and also by being built out of off-the-shelf components not typically rated for spaceflight. For example, it gets its power solely from AA batteries and uses an Arduino for its operation and other research.

The satellite is currently in orbit, and has already descended from an altitude of 520 km to 470 km. While it won’t help reduce the existing amount of debris in orbit, the research team hopes to demonstrate that small satellites can be affordable and economically feasible without further contributing to the growing problem of space junk. If you’re looking to launch your own CubeSat one day, take a look at this primer which goes over most of the basics.

Mice Play In VR

March 14, 2023 by Bryan Cockfield 9 Comments

Virtual Reality always seemed like a technology just out of reach, much like nuclear fusion, the flying car, or Linux on the desktop. It seems to be gaining steam in the last five years or so, though, with successful video games from a number of companies as well as plenty of other virtual reality adjacent technology that seems to be picking up steam as well like augmented reality. Another sign that this technology might be here to stay is this virtual reality headset made for mice. Continue reading “Mice Play In VR” →

A cartoon vehicle is connected to two wires. One is connected to an illustrated Li anode and the other to a γ-sulfur/carbon nanofiber electrode. Lithium ions and organic carbonate representations float between the two electrodes below the car. A red dotted line between the electrodes symbolizes the separator.

Lithium Sulfur Battery Cycle Life Gets A Boost

January 24, 2023 by Navarre Bartz 11 Comments

Lithium sulfur batteries are often touted as the next major chemistry for electric vehicle applications, if only their cycle life wasn’t so short. But that might be changing soon, as a group of researchers at Drexel University has developed a sulfur cathode capable of more than 4000 cycles.

Most research into the Li-S couple has used volatile ether electrolytes which severely limit the possible commercialization of the technology. The team at Drexel was able to use a carbonate electrolyte like those already well-explored for more traditional Li-ion cells by using a stabilized monoclinic γ-sulfur deposited on carbon nanofibers.

The process to create these cathodes appears less finicky than previous methods that required tight control of the porosity of the carbon host and also increases the amount of active material in the cathode by a significant margin. Analysis shows that this phase of sulfur avoids the formation of intermediate fouling polysulfides which accounts for it’s impressive cycle life. As the authors state, this is far from a commercial-ready system, but it is a major step toward the next generation of batteries.

We’ve covered the elements lithium and sulfur in depth before as well as an aluminum sulfur battery that could be big for grid storage.

Researching Factorio…For Science

October 19, 2022 by Bryan Cockfield 15 Comments

Science has affirmatively answered a lot of questions that, looking back, could be seen as bizarre to have asked in the first place. Questions like “can this moldy cheese cure disease” or “can this rock perform math if we give it some electricity.” Among the more recent of this list is the question of whether or not the video game Factorio, in which the player constructs an elaborate factory, can be used as the basis for other academic work. As [Kenneth Reid] discusses in this talk, it most certainly can.

If you haven’t played the game, it’s a sort of real-time strategy (RTS) game where the player gathers materials to construct a factory while defending it from enemies. On the surface it might seem similar to Age of Empires or Starcraft, but its complexity is taken to extremes not found in other RTS games. The complexity hides nuance, and [Kenneth] points out that it’s an excellent simulator to study real-world problems such as vehicle routing problems, decision making, artificial intelligence, bin packing problems, and production planning, among a whole slew of other interesting areas of potential research.

[Kenneth] and his partners on this project also developed some software tools with interacting with a Factorio game without having to actually play it directly. The game includes an API which the team used to develop tools so that other researchers can use it as a basis for simulations and studies. There was a research paper published as well for more in-depth reading on the topic. We shouldn’t be too surprised that a game can be used in incredibly productive ways like this, either. Here’s another example of a toy being used to train engineers working in industrial automation.

Continue reading “Researching Factorio…For Science” →

New Parkinson’s Test Smells Success

September 14, 2022 by Lewin Day 38 Comments

Parkinson’s disease affects millions of people all over the world. The degenerative condition causes characteristic tremors, trouble walking, and often comes with complications including dementia, depression, and anxiety.

One of the major challenges around Parkinson’s disease involves diagnosis. There’s no single, commonly-available test that can confirm or rule out the disease. It’s can cause particular frustration as the disease is most treatable in its early stages.

That may soon change, however. One woman identified that she seemingly had the ability to “smell” the disease in those affected, and is now working with scientists to develop a test for the condition.

Follow Your Nose

The human sense of smell, by and large, isn’t particularly impressive. It helps us enjoy the scent of fresh bread baking in an oven, or the aroma of freshly cut grass. However, as a tool for inspecting and learning about the world around us, it really comes up short.

Some of us, though, are more capable in the olfactory department than others. Joy Milne from Perth, Scotland, is one such person. She happened to detected a change in her partner’s characteristic smell, one day, and twelve years later, they were diagnosed with Parkinson’s disease.

The idea that someone could “smell” a difference with people with Parkinson’s disease is an easy one to test. When Milne eventually put the idea together that the different smell she noticed was perhaps related to her husbands condition, she quickly drew the interest of scientists. With the aid of her partner, a former doctor, she teamed up with researchers Dr. Tilo Kunath and Professor Perdita Barran to investigate further. Continue reading “New Parkinson’s Test Smells Success” →

Complex Movements From Simple Inflatables, Thanks To Physics

July 24, 2022 by Donald Papp 5 Comments

Inflatable actuators that change shape based on injected pressure can be strong, but their big limitation is that they always deform in the same way.

The Kresling pattern, which inspired the actuator design.

But by taking structural inspiration from origami, researchers created 3D-printed actuators that show it is possible to get complex movements from actuators fed by only a single source of pressure. How is this done? By making the actuators physically bi-stable, in a way that doesn’t require additional sources of pressure.

The key is a modified design based on the Kresling pattern, with each actuator having a specially-designed section (the colored triangles in the image above) that are designed to pop out under a certain amount of positive pressure, and remain stable after it has done so. This section holds its shape until a certain amount of negative pressure is applied, and the section pops back in.

Whether or not this section is popped out changes the actuator’s shape, therefore changing the way it deforms. This makes a simple actuator bi-stable and capable of different movements, using only a single pressure source. Stack up a bunch of these actuators, and with careful pressure control, complex movements become possible. See it in action in two short videos, embedded just below the page break.

Continue reading “Complex Movements From Simple Inflatables, Thanks To Physics” →

New Resin Printing Method Creates Objects In Seconds

June 1, 2022 by Bryan Cockfield 20 Comments

For anyone looking to buy a 3D printer at home, the first major decision that needs to be made is whether to get a resin printer or a filament printer. Resin has the benefits of finer detail, but filament printers are typically able to produce stronger prints. Within those two main camps are various different types and sizes to choose from, but thanks to some researchers at Switzerland’s École polytechnique fédérale de Lausanne (EPFL) there’s a new type of resin printer on the horizon that can produce prints nearly instantaneously.

The method works similarly to existing resin printers by shining a specific light pattern on the resin in order to harden it. The main difference is that the resin is initially placed in a cylinder and spun at a high speed, and the light is shined on the resin at different angles with very precise intensities and timings in order to harden the resin in specific areas. This high-speed method allows the printer to produce prints in record-breaking time. The only current downside, besides the high price for the prototype printer, is that it’s currently limited to small prints.

With the ability to scale in the future and the trend of most new technologies to come down in price after they have been on the market for some amount of time, it would be groundbreaking to be able to produce prints with this type of speed if printers like these can be scalable. Especially if they end up matching the size and scale of homemade printers like this resin printer.

Thanks to [suicidal.banana] for the tip!