A U.S. Navy engineer filed an intriguing patent for energy’s holy grail, a compact nuclear fusion reactor; the world’s largest 3D printer produced — what else? — the world’s largest 3D-printed object; and a lab in San Diego is building a better, softer robot. Here are this week’s coolest scientific advances.
What is it? A U.S. Navy engineer filed a patent for a compact fusion reactor that could create tremendous amounts of power while fitting onto a small craft — like a plane. (This inventor’s been busy: He’s the same guy who received a patent earlier this year for a flying device resembling a UFO.)
Why does it matter? A nuclear fusion reactor has long been a kind of holy grail among energy scientists. Taking advantage of the same reaction that keeps the sun shining, nuclear fusion could produce basically limitless amounts of carbon-free energy, and unlike nuclear fission — the atom-splitting reaction that fuels today’s nuclear power plants — fusion doesn’t generate long-lasting radioactive waste. “If scientists were able to harness fusion energy, all it would do is completely change the course of humanity,” writes Popular Mechanics’ Jennifer Leman.
How does it work? Rather than splitting the atom, nuclear fusion works by uniting hydrogen isotopes — basically squeezing hydrogen atoms under conditions of immense pressure and exorbitant temperatures (think hundreds of millions of degrees Fahrenheit) to produce helium, releasing energy in the process. Scientists look to technology like superconductors to manage this feat, but even the experimental versions they’ve created are somewhere around the size of a building — and, due to their instability, can generate energy for only seconds or minutes. The heart of the Navy’s patent is a device called a dynamic fusors, which pumps fuel gases into a vacuum chamber where the fusion reaction takes place. Nobody knows quite what to make of it yet, though; the project is cloaked in secrecy and the designs, according to Popular Mechanics, “stretch the limits of science.”
What is it? Capturing the enormous amount of plastics that humans are dumping into the world’s oceans is a big enough problem — but then there’s the matter with what to do with that plastic instead. Priyanka Bakaya, the founder of Renewlogy and an associated nonprofit called Renew Oceans, had one idea: Why not turn it into fuel?
Why does it matter? Bakaya began the project at MIT’s Sloan School of Management in 2009 to try to address an environmental crisis that has not yet abated. According to National Geographic, about 8 million tons of plastic waste ends up every year in the world’s oceans, where it stays. It can take nature centuries to break plastic down. Through Renew Oceans, Bakaya is focusing on rivers, one of the channels by which plastic ends up in the ocean — including the Ganges, one of the most polluted rivers in the world.
How does it work? In the Ganges basin of India, Renew Oceans is incentivizing the collection of plastic waste by installing “reverse vending machines” into which residents can deposit plastic in exchange for coupons. In the system developed by Bakaya’s Renewlogy, those plastics are shredded and then put through a chemical reformer, where they’re further broken down by a catalyst. Three-quarters of what’s left is converted into high-value fuels, including diesel fuel — 60 barrels of fuel for every 10 tons of plastic.
What is it? What good is having the world’s largest 3D printer if you can’t create the world’s largest 3D-printed object? Recently the University of Maine’s Advanced Structures and Composites Center won a triple-header in the 3D-printing sweepstakes, honored with Guinness World Records for world’s biggest prototype polymer 3D printer, world’s biggest solid 3D-printed object and world’s biggest 3D-printed boat. (Cue “Jaws” theme.)
Why does it matter? On hand for the ceremony, U.S. Senator Angus King said, “This is probably the biggest day for this university since Stephen King matriculated in 1965.” Habib Dagher, founding director of the composites center, told the AP that the huge printer will be able to assist companies in prototyping products by speeding up the process — the 5,000-pound boat was printed in just 72 hours. “This new printer is going to allow us to innovate so much faster by having prototypes made faster than in the past,” Dagher said. A collaboration between the university and Oak Ridge National Laboratory, the project will continue to focus on “large-scale, biobased additive manufacturing.”
How does it work? “Biobased” refers to the next phase of research, as engineers are working on developing printer feedstock — that is, the material the printer prints with — that involves wood cellulose, for a material that’s ultimately “stronger, durable and recyclable,” according to the AP: “If it works according to plan, the printer will be able to quickly produce items like molds for boats or concrete casks that could be recycled afterward.” Plus, it takes advantage of a resource that Maine is rich in: trees.
What is it? “Biggest in the world” is probably not the spec being sought by the U.S. Army under a new advanced manufacturing policy: It’s looking to get tech like 3D printers out into the field, where soldiers could print their own replacement parts for a tank — for instance — rather than wait for them to be shipped out.
Why does it matter? Basically, economy and logistics. “If you can produce them much faster, and have them on hand, you can reduce costs because you can be lighter,” Army Secretary Ryan D. McCarthy said in an interview with the Army Times. Advanced manufacturing could also improve the Army’s “logistics train,” he added: “If you had an expeditionary capability, for example, to print parts, you’d be able to extend the range of a brigade combat team. Their ability to replace parts quickly, doing it within hours, as [opposed] to weeks. … There’s an immediate return where you can put it in to tactical formations.”
How does it work? According to the Army Times, McCarthy’s initiative “will put strategic guidance out to the service and industry partners to indicate that Army leaders will be putting the resources, people and funding into advanced manufacturing technology in future funding plans.” McCarthy and Alexis L. Ross, a deputy assistant Army secretary, also described the initiative as a way to keep pace with private industry — like aviation, where many airplane parts are already 3D-printed — and other countries like China. “If we don’t start taking action, we will fall behind and we need to catch up,” Ross said.
What is it? With the help of electrically controlled “soft, tubular actuators,” engineers at the University of California San Diego have found a way to make soft robots that are “compact, portable and multifunctional.”
Why does it matter? As UCSD explains, a typical problem with soft actuators is that they’re bulky, because their movements need to be controlled via pumping air or fluid through their innards. (An actuator is, essentially, the part of a machine that moves other parts.) The UCSD researchers found a way around this by creating actuators out of a material called liquid crystal elastomers, which can move, change shape or contract in response to electric stimuli. “This feature makes our tubular actuators compatible with most low-cost, commercially available electronic devices and batteries,” said mechanical and aerospace engineering professor Shengqiang Cai, co-author of a paper in Science Advances.
How does it work? Two thin films of liquid crystal elastomers are layered in each actuator around three heating wires, like bread around sandwich filling, and then the material is rolled into a tube. An electrical charge coming down one or two of the wires causes the tube to bend; when all three of them receive a current, the tube contracts. As proofs of concept, the engineering team built an untethered robot that walks on four actuator legs and a gripper where three actuators function as the fingers.