Nov 7, 2019 12:02 AM
(This post was last modified: Nov 7, 2019 07:02 PM by C C.)
On the way to intelligent microrobots
https://www.psi.ch/en/media/our-research...icrorobots
RELEASE: Researchers at the Paul Scherrer Institute PSI and ETH Zurich have developed a micromachine that can perform different actions. First nanomagnets in the components of the microrobots are magnetically programmed and then the various movements are controlled by magnetic fields. Such machines, which are only a few tens of micrometres across, could be used, for example, in the human body to perform small operations. The researchers have now published their results in the scientific journal Nature.
The robot, which measures only a few micrometres across, is reminiscent of a paper bird made with origami – the Japanese art of paper folding. But, unlike a paper structure, the robot moves as if by magic without a visible force. It flaps its wings or bends its neck and retracts its head. These actions are all made possible by magnetism.
Researchers at the Paul Scherrer Institute PSI and ETH Zurich have assembled the micromachine from materials that contain small nanomagnets. These nanomagnets can be programmed to assume a particular magnetic orientation. When the programmed nanomagnets are then exposed to a magnetic field, specific forces act on them. If these magnets are located in flexible components, the forces acting on them cause the components to move.
The nanomagnets can be programmed again and again. This reprogramming results in different forces, and new movements result. For the construction of the microrobot, the researchers fabricated arrays of cobalt magnets on thin sheets of silicon nitride. The bird constructed from this material could then perform various movements, such as flapping, hovering, turning or side-slipping.
"The movements performed by the microrobot take place within milliseconds", says Laura Heyderman, head of the Laboratory for Multiscale Materials Experiments at PSI and professor for Mesoscopic Systems at the Department of Materials, ETH Zurich. "But programming of the nanomagnets only takes a few nanoseconds. This makes it possible to program the different movements one after the other. This means that the tiny microbird can first flap its wings, then slip to the side and afterwards flap again. "If needed, the bird could also hover in between", says Heyderman.
This novel concept is an important step towards micro- and nanorobots that not only store information to give a particular action, but also can be reprogrammed to carry out different tasks. "It is conceivable that, in the future, an autonomous micromachine will navigate through human blood vessels and perform biomedical tasks such as killing cancer cells", explains Bradley Nelson, head of Department of Mechanical and Process Engineering at ETH Zurich. “Other application areas are also conceivable, for example flexible microelectronics or microlenses that change their optical properties”, says Tianyun Huang, a researcher at the Institute of Robotics and Intelligent Systems at ETH Zurich.
In addition, applications are possible in which the characteristics of surfaces change. "For example, they could be used to create surfaces that can either be wetted by water or repel water", says Jizhai Cui, an engineer and researcher in the Mesoscopic Systems Lab.
https://www.youtube-nocookie.com/embed/YMygnALIjOA
Nuclear fusion is 'a question of when, not if'
https://www.bbc.com/news/science-environment-50267017
EXCERPT: The prospects for developing nuclear fusion as a feasible source of energy have significantly improved, say experts. The UK government has recently announced an investment of £200m to deliver electricity from a fusion reactor by 2040. Private companies and governments have told the BBC they aim to have demonstration models working within five years. But huge hurdles remain, say critics.
With the price of wind and solar continuing to drop, experts say these existing renewables might offer a more economical and timely method of tackling climate change and generating energy than an unproven technology like fusion. Nuclear fusion is an attempt to replicate the processes of the Sun on Earth. It differs significantly from nuclear fission, which has been our only way of getting electricity from atoms since the 1950s. Fission has proven to be hugely expensive. It generates large amounts of radioactive waste and raises serious concerns about safety and the proliferation of weapons.
Fusion is the process that drives our Sun. Every single second, millions of tonnes of hydrogen atoms crash together in the tremendous temperatures and pressures of our parent star. This forces them to break their atomic bonds and fuse to make the heavier element, helium. Natural, solar fusion generates enormous quantities of heat and light. For decades, researchers have been trying to replicate this process on Earth, or "build the Sun in a box" as one physicist dubbed it. The basic idea is to take a type of hydrogen gas, heat it to more than 100 million degrees until it forms a thin, fragile cloud called a plasma, and then control it with powerful magnets until the atoms fuse and release energy.
Potentially, it can generate power that is low carbon, with much smaller amounts of waste. It also comes without the danger of explosions. To deliver the fusion concept, countries have focused their energies on a major international co-operative effort called Iter. [...] In the UK, researchers have developed a different form of Tokamak, that more resembles an apple core than a doughnut. Called a Spherical Tokamak, it has the advantage of being more compact, potentially allowing future power plants to be located in towns and cities.
[...] While governments are wrestling with Iter, many are also driving ahead with their own national plans. China, India, Russia and the US among others are working on developing commercial reactors. As well as the UK government putting cash in, the European Investment Bank is pumping hundreds of millions of euros into an Italian programme to produce fusion energy by 2050. But perhaps the major excitement comes from private companies. They are usually smaller, nimbler, and they develop by making mistakes and learning from them quickly. There are now dozens of them around the world, raising funds and pushing forward often with different approaches to fusion than that seen in Iter and in the UK. Here's a brief sample of some different approaches to fusion... (MORE - details)
https://www.psi.ch/en/media/our-research...icrorobots
RELEASE: Researchers at the Paul Scherrer Institute PSI and ETH Zurich have developed a micromachine that can perform different actions. First nanomagnets in the components of the microrobots are magnetically programmed and then the various movements are controlled by magnetic fields. Such machines, which are only a few tens of micrometres across, could be used, for example, in the human body to perform small operations. The researchers have now published their results in the scientific journal Nature.
The robot, which measures only a few micrometres across, is reminiscent of a paper bird made with origami – the Japanese art of paper folding. But, unlike a paper structure, the robot moves as if by magic without a visible force. It flaps its wings or bends its neck and retracts its head. These actions are all made possible by magnetism.
Researchers at the Paul Scherrer Institute PSI and ETH Zurich have assembled the micromachine from materials that contain small nanomagnets. These nanomagnets can be programmed to assume a particular magnetic orientation. When the programmed nanomagnets are then exposed to a magnetic field, specific forces act on them. If these magnets are located in flexible components, the forces acting on them cause the components to move.
The nanomagnets can be programmed again and again. This reprogramming results in different forces, and new movements result. For the construction of the microrobot, the researchers fabricated arrays of cobalt magnets on thin sheets of silicon nitride. The bird constructed from this material could then perform various movements, such as flapping, hovering, turning or side-slipping.
"The movements performed by the microrobot take place within milliseconds", says Laura Heyderman, head of the Laboratory for Multiscale Materials Experiments at PSI and professor for Mesoscopic Systems at the Department of Materials, ETH Zurich. "But programming of the nanomagnets only takes a few nanoseconds. This makes it possible to program the different movements one after the other. This means that the tiny microbird can first flap its wings, then slip to the side and afterwards flap again. "If needed, the bird could also hover in between", says Heyderman.
This novel concept is an important step towards micro- and nanorobots that not only store information to give a particular action, but also can be reprogrammed to carry out different tasks. "It is conceivable that, in the future, an autonomous micromachine will navigate through human blood vessels and perform biomedical tasks such as killing cancer cells", explains Bradley Nelson, head of Department of Mechanical and Process Engineering at ETH Zurich. “Other application areas are also conceivable, for example flexible microelectronics or microlenses that change their optical properties”, says Tianyun Huang, a researcher at the Institute of Robotics and Intelligent Systems at ETH Zurich.
In addition, applications are possible in which the characteristics of surfaces change. "For example, they could be used to create surfaces that can either be wetted by water or repel water", says Jizhai Cui, an engineer and researcher in the Mesoscopic Systems Lab.
Nuclear fusion is 'a question of when, not if'
https://www.bbc.com/news/science-environment-50267017
EXCERPT: The prospects for developing nuclear fusion as a feasible source of energy have significantly improved, say experts. The UK government has recently announced an investment of £200m to deliver electricity from a fusion reactor by 2040. Private companies and governments have told the BBC they aim to have demonstration models working within five years. But huge hurdles remain, say critics.
With the price of wind and solar continuing to drop, experts say these existing renewables might offer a more economical and timely method of tackling climate change and generating energy than an unproven technology like fusion. Nuclear fusion is an attempt to replicate the processes of the Sun on Earth. It differs significantly from nuclear fission, which has been our only way of getting electricity from atoms since the 1950s. Fission has proven to be hugely expensive. It generates large amounts of radioactive waste and raises serious concerns about safety and the proliferation of weapons.
Fusion is the process that drives our Sun. Every single second, millions of tonnes of hydrogen atoms crash together in the tremendous temperatures and pressures of our parent star. This forces them to break their atomic bonds and fuse to make the heavier element, helium. Natural, solar fusion generates enormous quantities of heat and light. For decades, researchers have been trying to replicate this process on Earth, or "build the Sun in a box" as one physicist dubbed it. The basic idea is to take a type of hydrogen gas, heat it to more than 100 million degrees until it forms a thin, fragile cloud called a plasma, and then control it with powerful magnets until the atoms fuse and release energy.
Potentially, it can generate power that is low carbon, with much smaller amounts of waste. It also comes without the danger of explosions. To deliver the fusion concept, countries have focused their energies on a major international co-operative effort called Iter. [...] In the UK, researchers have developed a different form of Tokamak, that more resembles an apple core than a doughnut. Called a Spherical Tokamak, it has the advantage of being more compact, potentially allowing future power plants to be located in towns and cities.
[...] While governments are wrestling with Iter, many are also driving ahead with their own national plans. China, India, Russia and the US among others are working on developing commercial reactors. As well as the UK government putting cash in, the European Investment Bank is pumping hundreds of millions of euros into an Italian programme to produce fusion energy by 2050. But perhaps the major excitement comes from private companies. They are usually smaller, nimbler, and they develop by making mistakes and learning from them quickly. There are now dozens of them around the world, raising funds and pushing forward often with different approaches to fusion than that seen in Iter and in the UK. Here's a brief sample of some different approaches to fusion... (MORE - details)