AI Can Control SuperHeated Plasma Inside a Fusion Reactor

DeepMind’s streak of applying its world-class AI to hard science problems continues. In collaboration with the Swiss Plasma Center at EPFL—a university in Lausanne, Switzerland—the UK-based AI firm has now trained a deep reinforcement learning algorithm to control the superheated soup of matter inside a nuclear fusion reactor. The breakthrough, published in the journal Nature, could help physicists better understand how fusion works, and potentially speed up the arrival of an unlimited source of clean energy.

This is one of the most challenging applications of reinforcement learning to a real-world system,” says Martin Riedmiller, a researcher at DeepMind.

In nuclear fusion, the atomic nuclei of hydrogen atoms get forced together to form heavier atoms, like helium. This produces a lot of energy relative to a tiny amount of fuel, making it a very efficient source of power. It is far cleaner and safer than fossil fuels or conventional nuclear power, which is created by fissionforcing nuclei apart. It is also the process that powers stars.

Controlling nuclear fusion on Earth is hard, however. The problem is that atomic nuclei repel each other. Smashing them together inside a reactor can only be done at extremely high temperatures, often reaching hundreds of millions of degreeshotter than the center of the sun. At these temperatures, matter is neither solid, liquid, nor gas. It enters a fourth state, known as plasma: a roiling, superheated soup of particles.

The task is to hold the plasma inside a reactor together long enough to extract energy from it. Inside stars, plasma is held together by gravity. On Earth, researchers use a variety of tricks, including lasers and magnets. In a magnet-based reactor, known as a tokamak, the plasma is trapped inside an electromagnetic cage, forcing it to hold its shape and stopping it from touching the reactor walls, which would cool the plasma and damage the reactor. Controlling the plasma requires constant monitoring and manipulation of the magnetic field. The team trained its reinforcement-learning algorithm to do this inside a simulation. Once it had learned how to control—and change—the shape of the plasma inside a virtual reactor, the researchers gave it control of the magnets in the Variable Configuration Tokamak (TCV), an experimental reactor in Lausanne. They found that the AI was able to control the real reactor without any additional fine-tuning. In total, the AI controlled the plasma for only two seconds—but this is as long as the TCV reactor can run before getting too hot.

Source: https://www.technologyreview.com/

Nuclear Fusion Is Now a Question of “If”, Not “When”

A small railway town in southern England could go down in history as the place where nuclear fusion kicked off. The reaction process – which would generate vast amounts of low-carbon energy – has evaded scientists for decades, but a private company in Didcot, Oxfordshire says it’s now a question of if, not when.

Tokamak Energy is firing its nuclear reactor up to 50 million degrees celsius – almost twice the core temperature of the sun. By shooting 140,000 amps of electricity into a cloud of hydrogen gas, the team are trying to force hydrogen atoms to fuse, thereby creating helium. These fusion forces are the same ones that power the sun. While there’s no danger that Didcot could become the new centre of the solar system, the industrial estate could spark the start of a cheap, clean energy supply.

We will crack it,” CEO Chris Kelsall told the BBC on a recent trip, “the answer is out there right now with Mother Nature as we speak. What we have to do is find that key and unlock the safe to that solution. It will be found.”

Having ramped the temperature up to mind-boggling degrees, the experiment’s next step is to see if nuclear fusion can produce more energy than it uses. In case it rings alarm bells to anyone in the vicinity, nuclear fusion is very different from nuclear fission and its associated disasters. The process occurs inside a ‘tokamak’ – a device which uses a powerful magnetic field to contain the swirling cloud of hydrogen gas. This stops the superheated plasma from touching the edge of the vessel, as it would otherwise melt anything it comes into contact with. If anything goes wrong inside a fusion reactor, the device just stops – so there’s no risk of this astronomical heat being unleashed.

The plasma has to be heated to 10 times the temperature of the sun to get it going, and is capable of fusing two hydrogen nuclei into a helium nucleus. Nuclear fission, on the other hand, is the dangerous kind. This creates energy by splitting one ‘heavy’ atom (typically uranium) into two. This breakdown generates a large amount of radioactive waste in the process, which remains hazardous for years. Fusion cannot produce a runaway chain reaction, like the one that happened at Chernobyl in 1986, so no exclusion zone is needed around Milton Park, Didcot, where the reactor is based. Laura Hussey, an editor who works minutes away at a publishing office on the business park, says she is “really encouraged to hear how safe it is and really happy to see this big investment in clean energy.”

Source: https://www.euronews.com/

All-Terrain NanoRobot Flips Through A Live Colon

A rectangular robot as tiny as a few human hairs can travel throughout a colon by doing back flips, Purdue University engineers have demonstrated in live animal models. Why the back flips? Because the goal is to use these robots to transport drugs in humans, whose colons and other organs have rough terrain. Side flips work, too. Why a back-flipping robot to transport drugs? Getting a drug directly to its target site could remove side effects, such as hair loss or stomach bleeding, that the drug may otherwise cause by interacting with other organs along the way.

The study, published in the journal Micromachines, is the first demonstration of a microrobot tumbling through a biological system in vivo. Since it is too small to carry a battery, the microrobot is powered and wirelessly controlled from the outside by a magnetic field.


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When we apply a rotating external magnetic field to these robots, they rotate just like a car tire would to go over rough terrain,” said David Cappelleri, a Purdue associate professor of mechanical engineering. “The magnetic field also safely penetrates different types of mediums, which is important for using these robots in the human body.

The researchers chose the colon for in vivo experiments because it has an easy point of entry – and it’s very messy. “Moving a robot around the colon is like using the people-walker at an airport to get to a terminal faster. Not only is the floor moving, but also the people around you,” said Luis Solorio, an assistant professor in Purdue’s Weldon School of Biomedical Engineering. “In the colon, you have all these fluids and materials that are following along the path, but the robot is moving in the opposite direction. It’s just not an easy voyage.

But this magnetic microrobot can successfully tumble throughout the colon despite these rough conditions, the researchers’ experiments showed. The team conducted the in vivo experiments in the colons of live mice under anesthesia, inserting the microrobot in a saline solution through the rectum. They used ultrasound equipment to observe in real time how well the microrobot moved around.

Source: https://www.purdue.edu/