quarta-feira, 19 de novembro de 2014

R&D–Research and Development

 

Research and development (R&D), also known in Europe as research and technical (or technological) development (RTD), is a general term for activities related to the enterprise of corporate or governmental innovation. The activities that are classified as R&D differ from company to company, but there are two primary models, with an R&D department being either staffed by engineers and tasked with directly developing new products, or staffed with industrial scientists and tasked with applied research in scientific or technological fields which may facilitate future product development. In either case, R&D differs from the vast majority of corporate activities in that it is not often intended to yield immediate profit, and generally carries greater risk and an uncertain return on investment

Background

New product design and development is more often than not a crucial factor in the survival of a company. In an industry that is changing fast, firms must continually revise their design and range of products. This is necessary due to continuous technology change and development as well as other competitors and the changing preference of customers. Without an R&D program, a firm must rely on strategic alliances, acquisitions, and networks to tap into the innovations of others.

A system driven by marketing is one that puts the customer needs first, and only produces goods that are known to sell. Market research is carried out, which establishes what is needed. If the development is technology driven then R&D is directed toward developing products that market research indicates will meet an unmet need.

In general, R&D activities are conducted by specialized units or centers belonging to a company, or can be out-sourced to a contract research organization, universities, or state agencies. In the context of commerce, "research and development" normally refers to future-oriented, longer-term activities in science or technology, using similar techniques to scientific research but directed toward desired outcomes and with broad forecasts of commercial yield.

Statistics on organizations devoted to "R&D" may express the state of an industry, the degree of competition or the lure of progress. Some common measures include: budgets, numbers of patents or on rates of peer-reviewed publications. Bank ratios are one of the best measures, because they are continuously maintained, public and reflect risk.

In the U.S., a typical ratio of research and development for an industrial company is about 3.5% of revenues; this measure is called "R&D intensity". A high technology company such as a computer manufacturer might spend 7%. Although Allergan (a biotech company) tops the spending table with 43.4% investment, anything over 15% is remarkable and usually gains a reputation for being a high technology company. Companies in this category include pharmaceutical companies such as Merck & Co. (14.1%) or Novartis (15.1%), and engineering companies like Ericsson (24.9%). Such companies are often seen as credit risks because their spending ratios are so unusual.

Generally such firms prosper only in markets whose customers have extreme needs, such as medicine, scientific instruments, safety-critical mechanisms (aircraft) or high technology military armaments. The extreme needs justify the high risk of failure and consequently high gross margins from 60% to 90% of revenues. That is, gross profits will be as much as 90% of the sales cost, with manufacturing costing only 10% of the product price, because so many individual projects yield no exploitable product. Most industrial companies get 40% revenues only.

On a technical level, high tech organizations explore ways to re-purpose and repackage advanced technologies as a way of amortizing the high overhead. They often reuse advanced manufacturing processes, expensive safety certifications, specialized embedded software, computer-aided design software, electronic designs and mechanical subsystems.

Research has shown that firms with a persistent R&D strategy outperform those with an irregular or no R&D investment program.

source : Wikipedia-en

Report: China headed to overtake EU, U.S. in science and technology spending

 

Wed, 11/12/2014 - 11:59am

Catherine Bremer, OECD

 

Squeezed R&D budgets in the EU, Japan and U.S. are reducing the weight of advanced economies in science and technology research, patent applications and scientific publications and leaving China on track to be the world’s top R&D spender by around 2019, according to a OECD report.

The OECD Science, Technology and Industry Outlook 2014 finds that with R&D spending by most OECD governments and businesses yet to recover from the economic crisis, the OECD’s share in global R&D spending has slipped from 90% to 70% in a decade.

Annual growth in R&D spending across OECD countries was 1.6% over 2008-12, half the rate of 2001-08 as public R&D budgets stagnated or shrank in many countries and business investment was subdued. China’s R&D spending meanwhile doubled from 2008 to 2012.

Gross domestic expenditure on R&D (GERD) in 2012 was USD 257 billion in China, USD 397 billion in the United States, USD 282 billion for the EU28 and USD 134 billion in Japan.

The report warns that with public finances still tight in many countries, the ability of governments to compensate for lower business R&D with public funding, as they did during the worst of the economic downturn, has become more limited. Other key findings include:

  • 2012 R&D spending surpassed USD 1.1 trillion in OECD countries and stood at USD 330 billion in the BRIICS (Brazil, Russia, India, Indonesia, China and South Africa).
  • Korea became the world’s most R&D intensive country in 2012, spending 4.36% of GDP on R&D, overtaking Israel (3.93%) and versus an OECD average of 2.40%.
  • The BRIICS produced around 12% of the top-quality scientific publications in 2013, almost twice its share of a decade ago and compared to 28% in the United States.
  • China and Korea are now the main destinations of scientific authors from the United States and experienced a net “brain gain” over 1996-2011.
  • European countries are diverging in R&D as some move closer to their R&D/GDP targets (Denmark, Germany) and others (Portugal, Spain) fall further behind.
  • In most countries, 10% to 20% of business R&D is funded with public money, using various investment instruments and government targets.

View Report

Source: OECD

Lighter, cheaper radio wave device could transform telecommunications

 

Wed, 11/12/2014 - 11:18am

Sandra Zaragoza, The Univ. of Texas at Austin

 

Radio wave circulator developed by researchers at the Cockrell School of Engineering.

Radio wave circulator developed by researchers at the Cockrell School of Engineering.Researchers at the Cockrell School of Engineering at The Univ. of Texas at Austin have achieved a milestone in modern wireless and cellular telecommunications, creating a radically smaller, more efficient radio wave circulator that could be used in cellphones and other wireless devices, as reported in Nature Physics.

The new circulator has the potential to double the useful bandwidth in wireless communications by enabling full-duplex functionality, meaning devices can transmit and receive signals on the same frequency band at the same time.

The key innovation is the creation of a magnetic-free radio wave circulator.

Since the advent of wireless technology 60 years ago, magnetic-based circulators have been in principle able to provide two-way communications on the same frequency channel, but they are not widely adopted because of the large size, weight and cost associated with using magnets and magnetic materials.

Freed from a reliance on magnetic effects, the new circulator has a much smaller footprint while also using less expensive and more common materials. These cost and size efficiencies could lead to the integration of circulators within cellphones and other microelectronic systems, resulting in substantially faster downloads, fewer dropped calls and significantly clearer communications.

The team of researchers, led by Associate Professor Andrea Alu, has developed a prototype circulator that is 2 cm in size—more than 75 times smaller than the wavelength of operation. The circulator may be further scaled down to as small as a few microns, according to the researchers. The design is based on materials widely used in integrated circuits such as gold, copper and silicon, making it easier to integrate in the circuit boards of modern communication devices.

“We are changing the paradigm with which isolation and two-way transmission on the same frequency channel can be achieved. We have built a circulator that does not need magnets or magnetic materials,” Alu said.

The researchers’ device works by mimicking the way magnetic materials break the symmetry in wave transmission between two points in space, a critical function that allows magnetic circulators to selectively route radio waves. With the new circulator, the researchers accomplish the same effect, but they replaced the magnetic bias with a traveling wave spinning around the device.

Another unique feature is that the new circulator can be tuned in real time over a broad range of frequencies, a major advantage over conventional circulators.

“With this technology, we can incorporate tunable nonreciprocal components in mobile platforms,” said Nicholas Estep, lead researcher and a doctoral student in the Dept. of Electrical and Computer Engineering. “In doing so, we may pave the way to simultaneous two-way communication in the same frequency band, which can free up chunks of bandwidth for more effective use.”

For telecommunications companies, which pay for licenses to use frequencies allotted by the U.S. Federal Communications Commission, a more efficient use of the limited available bandwidth means significant cost advantages.

Additionally, because the design of the circulator is scalable and capable of circuit integration, it can potentially be placed in wireless devices.

“We envision micron-sized circulators embedded in cellphone technology. When you consider cellphone traffic during high demand events such as a football game or a concert, there are enormous implications opened by our technology, including fewer dropped calls and clearer communications,” Estep said.

The circulator also could benefit other industries that currently use magnetic-based circulators. For instance, circulators used in phased arrays and radar systems for aircraft, ships and satellites can be extremely heavy and large, so minimizing the size of these systems could provide significant savings.

“We are also bringing this paradigm to other areas of science and technology,” Alu said. “Our research team is working on using this concept to protect lasers and to create integrated nano-photonic circuits that route light signals instead of radio waves in preferred directions.”

Source: Univ. of Texas at Austin

Why We Selfie

 

469875265.jpg - Tang Ming Tung/Getty Images

Tang Ming Tung/Getty Images

Unsurprisingly, the practice of photographing oneself and sharing that image via social media is more common among Millennials (aged 18 to 33 at the time of the survey): more than one in two has shared a selfie. So have nearly a quarter of those classified as Generation X (loosely defined as those born between 1960 and the early 1980s). The selfie has gone mainstream.

Evidence of its mainstream nature is seen in other aspects of our culture too. In 2013 "selfie" was not only added to the Oxford English Dictionary, but also named Word of the Year. Since late January, 2014 the music video for "#Selfie" by The Chainsmokers has been viewed on YouTube over 250 million times. Though recently cancelled, a network television show focused on a fame-seeking and image conscious woman titled "Selfie" debuted this fall. And, the reigning queen of the selfie, Kim Kardashian West, is slated to debut in 2015 a collection of selfies in book form, titled Selfish. Some, like yours truly, might suggest we are living in the moment of "Peak Selfie" (à la, Peak Oil).

Yet, despite the ubiquity of the practice and how many of us are doing it (1 in 4 Americans!), a pretense of taboo and disdain surrounds it. An assumption that sharing selfies is or should be embarrassing runs throughout the journalistic and scholarly coverage on the topic. Many report statistics on the practice by noting how many "admit" to sharing them. Descriptors like "vain" and "narcissistic" inevitably become a part of any conversation about selfies. Qualifiers like "special occasion," "beautiful location," and "ironic" are used to justify them.

The usual reasons given--vanity, narcissism, fame-seeking--are as shallow as those who critique the practice suggest it is. From the sociological perspective there is always more to a mainstream cultural practice than meets the eye. Let's use it to dig deeper into the question of why we selfie.

1. Technology Compels Us

Simply put, physical and digital technology makes it possible, so we do it. The idea that technology structures the social world and our lives is a sociological argument as old as Marx, and one oft repeated by theorists and researchers who have tracked the evolution of communication technologies--and others too--over time. The selfie is not a new form of expression. Artists have created self-portraits for millennia, from cave to classical paintings, to early photography and modern art. What's new about today's selfie is its commonplace nature, and its ubiquity. Technological advancement liberated the self-portrait from the art world and gave it to the masses.

Now, those physical and digital technologies that allow for the selfie act upon us as a form of technological rationality (a term coined by critical theorist Herbert Marcuse in his book One-Dimensional Man). They exert a rationality of their own which shapes how we live our lives. Digital photography, front-facing cameras, social media platforms, and wireless communications begat a host of expectations and norms which now infuse our culture. We can, and so we do. But also, we do because both the technology and our culture expect us to.

2. Identity Work Has Gone Digital

We are not isolated beings living strictly individuated lives. We are social beings who live in societies, and as such, our lives are fundamentally shaped by social relations with other people, institutions, and social structures. As photos meant to be shared, selfies are not individual acts; they are social acts. Selfies, and our presence on social media generally, is a part of what sociologists David Snow and Leon Anderson describe as "identity work"--the work that we do on a daily basis to ensure that we are seen by others as we wish to be seen. Far from a strictly innate or internal process, the crafting and expressing of identity has long been understood by sociologists as a social process. The selfies we take and share are designed to present a particular image of us, and thus, to shape the impression of us held by others.

Famed sociologist Erving Goffman described the process of "impression management" in his book The Presentation of Self in Everyday Life. This term refers to the idea that we have a notion of what others expect of us, or what others would consider a good impression of us, and that this shapes how we present ourselves. Early American sociologist Charles Horton Cooley described the process of crafting a self based on what we imagine others will think of us as "the looking-glass self," whereby society acts as a sort of mirror to which we hold ourselves up. In the digital age our lives are increasingly projected onto, framed by, and filtered and lived through social media. It makes sense, then, that identity work takes place in this sphere. We engage in identity work as we walk through our neighborhoods, schools, and places of employment. We do it in how we dress and style ourselves; in how we walk, talk, and carry our bodies. We do it on the phone and in written form. And now, we do it in email, via text message, on Facebook, Twitter, Instagram, Tumblr, and LinkedIn. A self-portrait is the most obvious visual form of identity work, and its socially mediated form, the selfie, is now a common, perhaps even necessary form of that work.

3. The Meme Compels Us

In his book The Selfish Gene,evolutionary biologist Richard Dawkins offered a definition of the meme that became deeply important to cultural studies, media studies, and sociology. Dawkins described the meme as a cultural object or entity that encourages its own replication. It can take musical form, be seen in styles of dance, and manifest as fashion trends and art, among many other things. Memes abound on the internet today, often humorous in tone, but with increasing presence, and thus importance, as a form and mode of communication. In the pictorial forms that fill our Facebook and Twitter feeds, memes pack a powerful communicative punch with a combination of repetitious imagery and phrases. They are densely laden with symbolic meaning. As such, they compel their replication; for, if they were meaningless, if they had no cultural currency, they would never become a meme.

In this sense, the selfie is very much a meme. It has become a normative thing that we do that results in a patterned and repetitious way of representing ourselves. The exact style of representation may vary (sexy, sulky, serious, silly, ironic, drunk, "epic," etc.), but the form and general content--an image of a person or group of people who fill the frame, taken at arm's length--remains the same, time and again. The cultural constructs that we have collectively created shape how we live our lives, how we express ourselves, and who we are to others. The selfie, as a meme, is a cultural construct and a form of communication now deeply infused into our daily lives, and loaded with meaning and social significance.

So, now that we've got a working idea of why we selfie, let's take a look at what it all means, in a sociological sense, starting with those who offer critiques of the practice.

Snap 2014-11-19 at 21.47.35

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All aboard: Japan's maglev train hits 500 km/h

 

The experimental Shinkansen maglev train topped 500 km/h (311 mph) with passengers onboard...

The experimental Shinkansen maglev train topped 500 km/h (311 mph) with passengers onboard (Photo: Central Japan Railway Company)

 

The Central Japan Railway Company has whisked passengers along a section of track at up to 500 km/h (311 mph) during testing of the Shinkansen maglev train. The BBC reports that one hundred wide-eyed train enthusiasts were onboard the train's first manned voyage, with trials to continue over eight days.

Japan's famed bullet trains travel at speeds of around 320 kmh 200 (mph). But these may soon be left in the wake of the record-breaking levitating Shinkansen, which uses the force of electromagnets for propulsion and to hover above the track.

The benefits of these super fast, friction-free train systems have been explored for several years. China's state-owned press agency reported in 2012 that the China South Locomotive & Rolling Stock Corporation Limited, the country's largest rail vehicle maker, built a train inspired by an ancient Chinese sword capable of hitting 500 km/h (311 mph). But China's vision for ultra fast transport systems stretch back further than this, with Shanghai's Transrapid maglev train hitting the 500 km/h mark during testing in 2003.

On a more speculative note, earlier this year Chinese scientists built a super-maglev train that could theoretically hit speeds of 1,800 mph. This would be achieved, according to those involved, by running the train through a vacuum, eliminating the issue of air resistance. Then there's also Elon Musk's proposed (non-maglev) Hyperloop, which would aim to transport passengers from San Francisco to downtown Los Angeles in 30 minutes.

Testing began on Japan's new maglev train last year, after a prototype was revealed in November 2012. Unmanned journey's took place over an 18 km (11 mi) piece of track. The train is now the first to carry passengers at such speeds. The Daily Mail reports that 2,400 in total were selected by lottery to ride the train during its test period, drawn from a pool of almost 300,000. The system is due for completion in 2027 and is expected to halve travel time between Tokyo's Shinagawa Station and the city of Nagoya, a trip that takes around 80 minutes at present. The thrill experienced by the train's first passengers can be seen on this BBC video.

Sources:

BBC, Central Japan Railway Company

Trem de levitação magnética–Maglev ( Magnetic levitation transport)

 

Maglev de Shangai

Um trem de levitação magnética ou Maglev (Magnetic levitation transport) é um veículo semelhante a um comboio que transita numa linha elevada sobre o chão e é propulsionado pelas forças atrativas e repulsivas do magnetismo através do uso de supercondutores. Devido à falta de contato entre o veículo e a linha, a única fricção que existe, é entre o aparelho e o ar. Por consequência, os comboios de levitação magnética conseguem atingir velocidades enormes, com relativo baixo consumo de energia e pouco ruído, (existem projetos para linhas de maglev que chegariam aos 650 km/h.

Embora a sua enorme velocidade os torne potenciais competidores das linhas aéreas, o seu elevado custo de produção limitou-o, até agora, à existência de uma única linha comercial, o transrapid de Xangai. Essa linha faz o percurso de 30 km até ao Aeroporto Internacional de Pudong em apenas 8 minutos.

Tecnologia

Existem três tipos primários de tecnologia aplicada aos maglev. Uma que é baseada em ímãs supercondutores (suspensão eletrodinâmica), outra baseada na reação controlada de eletroímãs, (suspensão eletromagnética) e a mais recente e potencialmente mais econômica que usa ímãs permanentes (Inductrack).

O Japão e a Alemanha são os países que mais têm pesquisado esta tecnologia, tendo apresentado diversos projetos. Num deles o trem é levitado pela força repulsiva dos polos idênticos ou pela força atrativa dos polos diferentes dos ímãs. O trem é propulsionado por um motor linear, colocado na linha, no trem ou em ambas. Bobinas elétricas são massivamente colocadas ao longo da linha de modo a produzir o campo magnético necessário para a movimentação do trem, especulando-se que por isso que a construção de tal linha teria custos enormes.
China

O trem maglev de Xangai é um projeto importado da Alemanha, o Transrapid maglev, sendo capaz de uma velocidade operacional de 430 km/h e uma velocidade máxima de 501 km/h, ligando Xangai ao Aeroporto Internacional de Pudong desde Março de 2004.
Suspensão eletrodinâmica

Os engenheiros japoneses estão desenvolvendo uma versão concorrente dos trens maglev que usam um sistema de suspensão eletrodinâmica (SED), que é baseado na força de repulsão dos ímãs. A principal diferença entre os trens maglev japoneses e os alemães é que os trens japoneses usam eletroímãs com super-resfriadores e super-condutores. Este tipo de eletroímã pode conduzir eletricidade mesmo se após o suprimento de energia for cortado. No sistema SEM, que usa eletroímãs padrão, as bobinas somente conduzem a eletricidade quando um suprimento de energia está presente. Ao esfriar as bobinas, o sistema do Japão economiza energia. Entretanto, o sistema criogênico que costuma esfriar as bobinas pode ser caro. Outra diferença entre os sistemas é que os trens japoneses levitam mais ou menos 10 cm sobre os trilhos. Uma dificuldade no uso do sistema SED é que os trens maglev devem rodar sobre pneus de borracha até que ele alcance a velocidade de 100 km/h. Os engenheiros japoneses dizem que as rodas são uma vantagem se uma falha de energia causasse a queda do sistema. O trem Transrapid alemão está equipado com um suprimento de energia de emergência. Também os passageiros com marca-passo deveriam ser protegidos contra os campos magnéticos gerado pelos eletroímãs super-condutores.

O Inductrack é um dos tipos mais novos de SED que usa ímãs permanentes em temperatura ambiente para produzir campos magnéticos em vez de eletroímãs energizados ou ímãs super-condutores resfriados. O Inductrack usa uma fonte de energia para acelerar o trem somente até o início da levitação. Se a força falhar, o trem pode descer gradativamente e parar sobre suas rodas auxiliares.

O trilho é, em geral, um arranjo de curto circuitos elétricos contendo fios isolados. Em um projeto, esses circuitos são alinhados como degraus em uma escada. Conforme o trem se move, um campo magnético o repele, fazendo o trem levitar.

Há 2 projetos do Inductrack: Inductrack I e Inductrack II. O inductrack I é projetado para altas velocidades, enquanto o segundo é apropriado para baixas velocidades. Os trens Inductrack podem levitar mais alto com maior estabilidade. Contanto que se mova alguns quilômetros por hora, esse trem vai levitar em torno de 2,54 cm sobre o trilho. Uma grande falha sobre o trilho que significa que o trem não requereria sistemas complexos de sensores para manter a estabilidade.

Os ímãs permanentes não foram usados antes porque os cientistas achavam que eles não criariam força magnética suficiente. O projeto Inductrack suplanta este problema ao organizar os ímãs em um arranjo Halbach. Os ímãs são configurados para que a intensidade do campo magnético se concentre acima do arranjo, e não abaixo. Eles são feitos de um material mais novo compreendendo uma liga de boro, aço e neodímio, que gera um campo magnético mais forte. O projeto Inductrack II incorpora 2 arranjos Halbach para gerar um campo magnético mais forte em velocidade mais baixa.

Brasil
Trem de alta velocidade no Brasil

O Maglev Cobra é um trem de levitação desenvolvido na UFRJ (Universidade Federal do Rio de Janeiro) pela Coppe (Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa em Engenharia) e pela Escola Politécnica através do LASUP (Laboratório de Aplicações de Supercondutores). O trem brasileiro, assim como o maglev alemão, flutua sobre os trilhos, tendo atrito apenas com o ar durante seu deslocamento. O Maglev Cobra se baseia em levitação, movendo-se sem atrito com o solo através de um motor linear de primário curto. O veículo foi concebido visando uma revolução no transporte coletivo através da alta tecnologia, de forma não poluente, energeticamente eficiente e de custo acessível para os grandes centros urbanos.

O custo de implantação do Maglev Cobra é significativamente menor do que o do metrô, chegando a custar apenas um terço deste. Sua velocidade normal de operação ocorrerá dentro de uma faixa de 70 a 100km/h, compatível à do metrô e ideal para o transporte público urbano.

Levitação magnética supercondutora

A tecnologia da levitação magnética supercondutora (SML) baseia-se na propriedade diamagnética dos supercondutores para exclusão do campo magnético do interior dos supercondutores. No caso dos supercondutores do tipo II, esta exclusão é parcial, o que diminui a força de levitação, mas conduz à estabilidade, dispensando sistemas de controle sofisticados ou rodas. Esta propriedade, que representa o grande diferencial em relação aos métodos EDL e EML, só pôde ser devidamente explorado a partir do final do século 20 com o advento de novos materiais magnéticos, como o Nd2Fe14B (NdFeB), e de pastilhas super-condutoras de alta temperatura crítica, como o YBa2Cu3OX (YBCO).

Os novos supercondutores de alta temperatura crítica podem ser resfriados com nitrogênio liquido (temperatura de ebulição -196°C) enquanto os supercondutores convencionais necessitam de hélio liquido (temperatura de ebulição –269°C), o que torna a refrigeração onerosa. Por se tratar da tecnologia mais recente, ainda não existe linha de teste em escala real. Em outros países, como no Brasil, existem linhas em modelo reduzido. No protótipo brasileiro, construido pelo grupo proponente deste projeto, o formato oval tem 30 metros de extensão, com guia linear formada por imãs de NdFeB compondo o circuito magnético e interagindo com os supercondutores de YBCO para levitação. O MagLev é acionado por motor linear síncrono (LSM) de armadura longa, alimentado com inversor de frequência.

Fonte :Wikipedia

Better micro-actuators to transport materials in liquids

 


Researchers have developed improved forms of tiny magnetic actuators thanks to new materials and a microscopic 3D printing technology.

Scientists have been conducting research on micrometre-sized actuators which one day may make it possible to transport drugs or chemical sensor molecules to specific locations throughout the human body. Researchers at ETH Zurich have now taken the development of such micro-devices a crucial step forward: a new production technology and new materials have made it possible to manufacture tiny actuators in any form and optimise them for future applications.

The elongated actuators elements, which can move through liquids, possess a helical shape and are magnetic. They are driven by an external rotating magnetic field; they align themselves along the magnetic field lines and rotate about their longitudinal axis. Due to their helical shape, they are able to swim forward through liquids.

When applying conventional fabrication techniques, the magnetic properties of these micro-objects depend on the shape of the devices themselves. This restriction made it difficult for researchers to develop actuators with precise control and directional stability, as doctoral student Christian Peters from the group led by Christofer Hierold, Professor of Micro and Nanosystems, explains: "Previously, these elements wobbled as they moved forward, and they were less efficient because their magnetic properties were not ideal. We have now developed a material and a fabrication technique with which we can adjust the magnetic properties independent of the object's geometry."

Microscopic 3D printer

The scientists utilised a light-sensitive, bio-compatible epoxy resin, in which they incorporated magnetic nanoparticles. In the first part of the curing stage, they exposed a thin layer of this material to a magnetic field. This field magnetised the nanoparticles, leading to a particle re-arrangement in form of parallel lines. The orientation of these lines determines the magnetic properties of the material. The researchers then manufactured the tiny elongated structures out of the modified epoxy film via two-photon polymerisation. This technique is similar to a microscopic 3D printer: a laser beam is moved in a computer-controlled, three-dimensional manner within the epoxy resin layer, thus curing the resin locally. Uncured areas can then be washed away with a solvent.

This technique allowed the researchers to manufacture helical structures 60 micrometres in length and nine micrometres in diameter, and with a magnetisation perpendicular to the longitudinal axis. A conventional manufacturing method would not have allowed the production of an object with such magnetic properties, as the preferred magnetisation is usually in the direction of the longitudinal axis of an object, like a compass needle. The new actuators can be controlled precisely, they swim nearly four times as fast as previous elements, and they do not wobble.

New forms with larger surfaces

Previous micro-actuators usually took the shape of a corkscrew (helix), but thanks to the microscopic 3D fabrication technology the ETH scientists were able to produce modified shapes. In the study they fabricated structures similar to spiral-shaped, twisted strips and double-twisted wires. Tests show that these forms swim as fast as corkscrew-shaped actuators, but the new shapes differ from the latter in that their surface is two to four times larger. "This makes the actuators more interesting for certain applications," says Salvador Pané, research associate in the group led by Bradley Nelson, Professor of Robotics and Intelligent Systems.

If such elements are to carry medications or chemical sensor molecules to specific locations in the body, the actuators must be coated with the corresponding molecules. And the larger the element's surface, the larger the quantity of materials that can be transported. The researchers demonstrated that it is possible, in principle, to coat the structures with interesting biomedical materials by connecting antibodies to the surface of the spiral motors.

"But it is not just about swimming micro robots," says Peters. "The new technology can also be used when other micro-objects have to be manufactured with specific magnetic properties." The work is the result of many years of joint research between the two professors in the Department of Mechanical and Process Engineering in the fields of microsystems technology and micro-robotics, adds Pané. The group led by Nelson has many years' experience in the fabrication and application of magnetic micro robots, and the group led by Hierold has a strong competence in the integration of new materials into microsystems.