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Ultrafast Holographic Printer Creates 3D Objects in Mere Seconds
Rather than one layer at a time, this method creates an entire object all at once, using lasers.
Imagine this, you see something online you just have to have, like a rugged smartphone case emblazoned with your favorite character. You order it and instead of waiting for it to be delivered, your 3D printer fashions it for you, to your exact specifications, in seconds. Why don’t we have this right now? 3D printers can take hours or even days to create an object, making such a scenario difficult to implement.
3D printers are still a new technology with a lot of potential. Think of the cost savings to the consumer (no shipping costs), the time saved to the producer (no need to ship things anywhere), and to the environment (saving on exhaust from trucks, planes, delivery vans, producing unsold items, and so on). Not only could it transform manufacturing but the research and development process as well. Making prototypes fast and easy would revolutionize engineering and design.
The potential is there. What’s holding up additive printing, as it’s sometimes called, is that it's time intensive and the device is limited as to what shapes it can produce. The model we have today adds only one layer at a time.
Lattice work on the millimeter scale, produced by a new 3D printer technique. Credit: Shusteff et al., Science Advances.
Scientists at the Lawrence Livermore National Laboratory, in California, have now come up with a novel technique that can make complex objects in mere seconds, by adding several layers simultaneously. The details are in a report in the journal Science Advances.
There are two really big innovations here. The first is using a fast drying, photosensitive resin, and the second is the unique way the lasers are employed. In traditional 3D printing, a powerful laser is used to harden the resin into plastic. Here, the printer follows a pattern set up by a 3D laser model. Creation takes place inside a tank full of liquid resin.
Three weak lasers are used, so the resin doesn’t cure. Instead, it creates a holographic effect, forming a 3D model of what’s to be made inside the tank. Anywhere where the three lasers are made to come together unites them into one strong beam, which hardens the resin. In this way, rather than one layer at a time, multiple layers can be fabricated at once by orchestrating the lasers into complex patterns. This method can allow for pinpoint accuracy.
Once the pattern is complete, the lasers harden the resin in seconds, and the unused liquid is drained away, leaving the finished product behind. The process works with metal as well. But it’s a little different. Here, the lasers arrange metal dust into a pattern. Once complete, the dust is condensed into a solid by a laser or electron beam.
Volumetric 3D printing and the objects scientists have made so far. Credit: Shusteff et al., Science Advances.
LLNL engineer Maxim Shusteff led the study. He told New Atlas, "The fact that you can do fully 3D parts all in one step really does overcome an important problem in additive manufacturing." Not only is the new technique faster and able to create a wider variety of shapes, it eliminates the need for support structures current 3D printers often need to fashion objects. In addition to lattices, beams, squares, and other structures, it could be used to make something complex with moving parts, like a gearbox. Another advantage, it can print multiple objects at once, such as a set of chess pieces.
The objects made via volumetric 3D printing, as the technique is being called, aren’t yet able to produce as sophisticated a product as some commercial 3D printers out there today. Really, this was a proof of concept study. But Shusteff and his team believe they can reach the same level of resolution with their process. Future models may use LEDs rather than a complicated laser array, as the latter is expensive. Also “laser speckle” or when a laser interferes with itself, can cause noise and result in surface roughness on printed objects.
So far, Shusteff and colleagues have made a few shapes on the millimeter scale. Though the amount of power needed may steer entities away from using this technique for heavy manufacturing, it would be useful for creating biomedical implants, which need to be flexible and yet high resolution. Another option could be bioprinting living tissue. “We’ve taken a really good first shot at this,” Shusteff said, “but we’ve not yet taken it to the limit of its performance, so the space is wide open for us and others to demonstrate what this approach is capable of.”
To see volumetric 3D printing in action, click here:
Innovation in manufacturing has crawled since the 1950s. That's about to speed up.
Richard Feynman once asked a silly question. Two MIT students just answered it.
Here's a fun experiment to try. Go to your pantry and see if you have a box of spaghetti. If you do, take out a noodle. Grab both ends of it and bend it until it breaks in half. How many pieces did it break into? If you got two large pieces and at least one small piece you're not alone.
But science loves a good challenge<p>The mystery remained unsolved until 2005, when French scientists <a href="http://www.lmm.jussieu.fr/~audoly/" target="_blank">Basile Audoly</a> and <a href="http://www.lmm.jussieu.fr/~neukirch/" target="_blank">Sebastien Neukirch </a>won an <a href="https://www.improbable.com/ig/" target="_blank">Ig Nobel Prize</a>, an award given to scientists for real work which is of a less serious nature than the discoveries that win Nobel prizes, for finally determining why this happens. <a href="http://www.lmm.jussieu.fr/spaghetti/audoly_neukirch_fragmentation.pdf" target="_blank">Their paper describing the effect is wonderfully funny to read</a>, as it takes such a banal issue so seriously. </p><p>They demonstrated that when a rod is bent past a certain point, such as when spaghetti is snapped in half by bending it at the ends, a "snapback effect" is created. This causes energy to reverberate from the initial break to other parts of the rod, often leading to a second break elsewhere.</p><p>While this settled the issue of <em>why </em>spaghetti noodles break into three or more pieces, it didn't establish if they always had to break this way. The question of if the snapback could be regulated remained unsettled.</p>
Physicists, being themselves, immediately wanted to try and break pasta into two pieces using this info<p><a href="https://roheiss.wordpress.com/fun/" target="_blank">Ronald Heisser</a> and <a href="https://math.mit.edu/directory/profile.php?pid=1787" target="_blank">Vishal Patil</a>, two graduate students currently at Cornell and MIT respectively, read about Feynman's night of noodle snapping in class and were inspired to try and find what could be done to make sure the pasta always broke in two.</p><p><a href="http://news.mit.edu/2018/mit-mathematicians-solve-age-old-spaghetti-mystery-0813" target="_blank">By placing the noodles in a special machine</a> built for the task and recording the bending with a high-powered camera, the young scientists were able to observe in extreme detail exactly what each change in their snapping method did to the pasta. After breaking more than 500 noodles, they found the solution.</p>
The apparatus the MIT researchers built specifically for the task of snapping hundreds of spaghetti sticks.
(Courtesy of the researchers)
What possible application could this have?<p>The snapback effect is not limited to uncooked pasta noodles and can be applied to rods of all sorts. The discovery of how to cleanly break them in two could be applied to future engineering projects.</p><p>Likewise, knowing how things fragment and fail is always handy to know when you're trying to build things. Carbon Nanotubes, <a href="https://bigthink.com/ideafeed/carbon-nanotube-space-elevator" target="_self">super strong cylinders often hailed as the building material of the future</a>, are also rods which can be better understood thanks to this odd experiment.</p><p>Sometimes big discoveries can be inspired by silly questions. If it hadn't been for Richard Feynman bending noodles seventy years ago, we wouldn't know what we know now about how energy is dispersed through rods and how to control their fracturing. While not all silly questions will lead to such a significant discovery, they can all help us learn.</p>
Join Pulitzer Prize-winning reporter and best-selling author Charles Duhigg as he interviews Victoria Montgomery Brown, co-founder and CEO of Big Think.
Women today are founding more businesses than ever. In 2018, they made up 40% of new entrepreneurs, yet in that same year, they received just 2.2% of all venture capital investment. The playing field is off-balance. So what can women do?
In a recent study, researchers examined how Christian nationalism is affecting the U.S. response to the COVID-19 pandemic.
- A new study used survey data to examine the interplay between Christian nationalism and incautious behaviors during the COVID-19 pandemic.
- The researchers defined Christian nationalism as "an ideology that idealizes and advocates a fusion of American civic life with a particular type of Christian identity and culture."
- The results showed that Christian nationalism was the leading predictor that Americans engaged in incautious behavior.
A pastor at the chapel of the St. Josef Hospital on April 1, 2020 in Bochum, German
Sascha Schuermann/Getty Images<p>Christian nationalists, in general, believe the U.S. and God's will are tied together, and they want the government to embody conservative Christian values and symbols. As such, they also believe the nation's fate depends on how closely it adheres to Christianity.</p><p style="margin-left: 20px;">"Unsurprisingly then, in the midst of the COVID‐19 pandemic, conservative pastors prophesied God's protection over the nation, citing America's righteous support for President Trump and the prolife agenda," the researchers write.</p><p style="margin-left: 20px;">"Correspondingly, the link between Christian nationalism and God's influence on how COVID‐19 impacts America can be seen in proclamations about God's divine judgment for its immorality―with the logic being that God is using the pandemic to draw wayward America <em>back </em>to himself, which assumes the two belong together."</p><p>The logical conclusion to this kind of thinking: America can save itself not through cautionary measures, like mask-wearing, but through devotion to God. What's more, it stands to reason that Christian nationalists are less likely to trust the media and scientists, given that these sources are generally not concerned with promoting a conservative, religious view of the world.</p><p>(The researchers note that they're unaware of any research directly linking Christian nationalism to distrust of media sources, but that they're almost certain the two are connected.)</p>
Predicted values of Americans' frequency of incautious behaviors during the COVID‐19 pandemic across values of Christian nationalism
Perry et al.<p>In the new study, the researchers examined three waves of results from the Public and Discourse Ethics Survey. One wave of the survey was issued in May, and it asked respondents to rate how often they engaged in both incautious and precautionary behaviors.</p><p>Incautious behaviors included things like "ate inside a restaurant" and "went shopping for nonessential items," while precautionary behaviors included "washed my hands more often than typical" and "wore a mask in public."</p><p>To measure Christian nationalism, the researchers asked respondents to rate how strongly they agree with statements like "the federal government should advocate Christian values" and "the success of the United States is part of God's plan."</p><p>The results suggest that, compared to other groups, Christian nationalists are far less likely to wear masks, socially distance and take other precautionary measures amid the COVID-19 pandemic.</p><p style="margin-left: 20px;">"Christian nationalism was the leading predictor that Americans engaged in incautious behavior during the pandemic, and the second leading predictor that Americans avoided taking precautionary measures."</p><p>But that's not to say that religious beliefs are causing Americans to reject mask-wearing or social distancing. In fact, when the study accounted for Christian nationalist beliefs, the results showed that Americans with high levels of religiosity were likely to take precautionary measures for COVID-19.</p>
Limitations<p>Still, the researchers note that they're theorizing about the connections between Christian nationalism and COVID-19 behaviors, not documenting them directly. What's more, they suggest that certain experiences — such as having a family member that contracts COVID-19 — might change a Christian nationalist's behaviors during the pandemic.</p><p style="margin-left: 20px;">"Limitations notwithstanding, the implications of this study are important for understanding Americans' curious inability to quickly implement informed and reasonable strategies to overcome the threat of COVID‐19, an inability that has likely cost thousands of lives," they write.</p>
Parental anxieties stem from the complex relationship between technology, child development, and the internet's trove of unseemly content.