Power for Electronic ‘Super Skin’

Power for Electronic ‘Super Skin’

By Louis Bergeron, Stanford University

Thursday, March 10, 2011

The foundation for the artificial skin is a flexible organic transistor, made with flexible polymers and carbon-based materials.

"Super skin" is what Stanford researcher Zhenan Bao wants to create. She’s already developed a flexible sensor that is so sensitive to pressure it can feel a fly touch down. Now she’s working to add the ability to detect chemicals and sense various kinds of biological molecules. She’s also making the skin self-powering, using polymer solar cells to generate electricity. And the new solar cells are not just flexible, but stretchable – they can be stretched up to 30 percent beyond their original length and snap back without any damage or loss of power.

Super skin, indeed.

"With artificial skin, we can basically incorporate any function we desire," said Bao, a professor of chemical engineering. "That is why I call our skin ‘super skin.’ It is much more than what we think of as normal skin."

The foundation for the artificial skin is a flexible organic transistor, made with flexible polymers and carbon-based materials. To allow touch sensing, the transistor contains a thin, highly elastic rubber layer, molded into a grid of tiny inverted pyramids. When pressed, this layer changes thickness, which changes the current flow through the transistor. The sensors have from several hundred thousand to 25 million pyramids per square centimeter, corresponding to the desired level of sensitivity.

To sense a particular biological molecule, the surface of the transistor has to be coated with another molecule to which the first one will bind when it comes into contact. The coating layer only needs to be a nanometer or two thick.

"Depending on what kind of material we put on the sensors and how we modify the semiconducting material in the transistor, we can adjust the sensors to sense chemicals or biological material," she said.

Bao’s team has successfully demonstrated the concept by detecting a certain kind of DNA. The researchers are now working on extending the technique to detect proteins, which could prove useful for medical diagnostics purposes.

"For any particular disease, there are usually one or more specific proteins associated with it – called biomarkers – that are akin to a ‘smoking gun,’ and detecting those protein biomarkers will allow us to diagnose the disease," Bao said.

The same approach would allow the sensors to detect chemicals, she said. By adjusting aspects of the transistor structure, the super skin can detect chemical substances in either vapor or liquid environments.

Regardless of what the sensors are detecting, they have to transmit electronic signals to get their data to the processing center, whether it is a human brain or a computer.

Having the sensors run on the sun’s energy makes generating the needed power simpler than using batteries or hooking up to the electrical grid, allowing the sensors to be lighter and more mobile. And having solar cells that are stretchable opens up other applications.

A recent research paper by Bao, describing the stretchable solar cells, will appear in an upcoming issue of Advanced Materials. The paper details the ability of the cells to be stretched in one direction, but she said her group has since demonstrated that the cells can be designed to stretch along two axes.

The cells have a wavy microstructure that extends like an accordion when stretched. A liquid metal electrode conforms to the wavy surface of the device in both its relaxed and stretched states.

"One of the applications where stretchable solar cells would be useful is in fabrics for uniforms and other clothes," said Darren Lipomi, a postdoctoral fellow in Bao’s lab and lead author of the paper.

"There are parts of the body, at the elbow for example, where movement stretches the skin and clothes," he said. "A device that was only flexible, not stretchable, would crack if bonded to parts of machines or of the body that extend when moved." Stretchability would be useful in bonding solar cells to curved surfaces without cracking or wrinkling, such as the exteriors of cars, lenses and architectural elements.

The solar cells continue to generate electricity while they are stretched out, producing a continuous flow of electricity for data transmission from the sensors.

Bao said she sees the super skin as much more than a super mimic of human skin; it could allow robots or other devices to perform functions beyond what human skin can do.

"You can imagine a robot hand that can be used to touch some liquid and detect certain markers or a certain protein that is associated with some kind of disease and the robot will be able to effectively say, ‘Oh, this person has that disease,’" she said. "Or the robot might touch the sweat from somebody and be able to say, ‘Oh, this person is drunk.’"

Finally, Bao has figured out how to replace the materials used in earlier versions of the transistor with biodegradable materials. Now, not only will the super skin be more versatile and powerful, it will also be more eco-friendly.


3D printing for architects

3D printing for architects

Initially, 3D printing was not created for architects. In fact, most 3D printer manufacturers probably didn’t even foresee their machines’ potential in architecture.

The printers were mainly designed for the aerospace and automotive industries, or other sectors requiring physical realization of elements in order to test their design.

Things have changed, and 3D CAD applications are now very much a part of the design process. 3D printing has become a strategic necessity for architects.

The question is no longer “should we go into this?” but rather “how are we going to integrate 3D printing into our business?”

Architects can use 3D printed models in the same way as hand-made ones. But they have the added benefit of being faster to design, less costly and more accurate.

Many architects recognize the ease of use of 3D modeling software such as Google SketchUp, which is particularly useful in the early stages of design, when multiple iterations of a model are required.

The problem is that SketchUp, like many other 3D CAD applications, is more of a rendering tool than a solid modeling system. Designers must therefore be especially careful when preparing their model for 3D printing to ensure a flawless print. To be honest, it should be noted that Google’s v8 of SketchUp has resulted in marked improvements in addressing the needs of solid modeling.

Below is an example that illustrates how 3D printing has become essential for any architecture firm.

On its blog, 3D printer manufacturer Zcorporation quotes from a recent article in Building Design.

We learn that British Education Secretary Michael Gove called Amanda Levet “Britain’s best architect” at the Globe Academy’s opening ceremony.

Said Gove: “So much care and attention and the work of Britain’s best architect has gone into providing you with the best possible building in which to spend the next few years.” He said everyone involved in the design had “shaped a building which is impressive on the outside and beautiful on the inside”.

OCCs Electrifying Chopper

Subject: OCCs Electrifying Chopper



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Whistleblower: Rolls-Royce Hid Repeated Defects

INDIANAPOLIS (AP) — Rolls-Royce Corp. concealed repeated defects at an aircraft engine plant in Indianapolis and fired a safety official for reporting the problems, according to a whistleblower lawsuit filed in federal court.

Lawyers for Thomas McArtor said a federal court in Indianapolis unsealed his complaint Tuesday, 34 months after it was filed. His lawyer criticized the long-running secrecy.

"Aircraft manufacturers enjoy a special position of public trust," said Mike Kanovitz of Loevy & Loevy. "It is arrogant for any of them to pick and choose which defects the public gets to hear about. Aircraft operators and airline travelers deserve complete transparency so that they can evaluate the risks and take steps to protect themselves."

The Associated Press left several e-mail and telephone messages for London-based Rolls-Royce seeking comment Wednesday.

McArtor was a senior quality control official for Rolls-Royce and the Federal Aviation Administration’s chief designated airworthiness representative for the plant, according to the complaint. It said he worked there for 12 years before being fired in 2007.

The suit says the company cut quality controls to increase profits, then concealed information about an increase in defects from customers.

It says problems affect the Model 250, T56 and AE2100 engines, used in civilian and military aircraft. They include Bell helicopters, Saab turbo props, C130 transports, and the Kiowa military helicopter.

The suit says some engines from the plant have experienced ‘catastrophic failures," including nine that have failed in Iraq, causing the loss of U.S. lives.

Rolls-Royce was the manufacturer at a different plant of a Trent 900 engine that blew apart Nov. 4 on superjumbo Airbus A380 passenger jet operated by Qantas. The plane had about 450 passengers aboard and made a safe emergency landing.

Creaform Named 2010 Company of the Year by AQA

Subject: Creaform Named 2010 Company of the Year by AQA


Creaform Receives 2010 company of the Year Award from Quebec aerospace association

Montréal, December 9, 2010 – Creaform, world-class company offering 3D technology and engineering services, received last night the 2010 Quebec Aerospace Association (AQA) Company of the Year Award.

Of the 4 finalists, Creaform distinguished itself with strong financial management and strategic planning, innovation and continuous improvement, leadership and excellence in human resources management, dedication to the environment and sustainable development, corporate citizenship and involvement with the AQA. Most definitely, the fact that Montréal is one of the world’s 3 major aerospace centres confers an international dimension to this prize.

"We are absolutely thrilled and honoured to receive this award, said Stéphane Galibois, Director – Canada Technology Sales & Strategic Accounts for North America. The 3 other contenders are amazing companies, and it was certainly not an easy pick for the jury. Creaform is based in the province of Quebec, which has long been a high flyer among aerospace industry leaders. Our company works very hard to develop technologies and engineering services that meet the specific and stringent needs of aerospace major prime contractors, technical centres and world-class OEM. This award recognizes the hard work, passion and dedication of Creaform’s entire staff.”

World-class aerospace clients such as Bombardier, EADS, Pratt & Whitney, Embraer, Aircelle, Boeing, NASA, Héroux-Devtek and Cessna have improved their suite of equipment with technologies developed by Creaform.


Shaping an Obsession

A favorite media lament these days concerns the lack of high-school graduates prepared to go forth into design, engineering, or technology. That’s why we have seen so much push recently on STEM (science, technology, engineering, and mathematics) programs for our schools. Industry is clamoring for suitable people wanting to work in a technology-rich environment, and unfortunately, too many students are coming out of high school either uninterested or ill-prepared to take on the challenge of a technology degree. The same could be said of arts programs. Budget cuts across many school districts have lead to drastic slashes in all types of arts teaching, from music to painting.

So, for many students, whose interest might lie in art or technology (or as we will see, a bit of both) they are on their own. Whether they succeed in bootstrapping themselves into their career of choice depends largely on industry support, parental support, and in the end, their own gumption.

We recently ran on a story about a young man who is charting his career without the help of the school system. He is doing it on his own with financial and moral support from his parents. Jamie Goldstein is charting his own way.

Since 2006, when he first saw a picture of that year’s Camaro concept car, Goldstein knew that he wanted to be a car designer, what he now calls his “obsession.”

That may sound like the pipe dreams of a 12-year-old kid, but in Goldstein’s case, it was a dream that wouldn’t let go. In 2009, at the age of 15, and with his dream school, the Art Center College of Design in Pasadena, California, in his sights, Goldstein set about working on his portfolio; a good portfolio improves your chances of getting into a prestigious design school. Most young designers start their portfolios with sketches, drawings, renderings, and the like. But in Goldstein’s case, his very first portfolio project was to be a 1/18-scale clay model of his own concept car.

The thing is, Goldstein had almost no art experience, no mentor, and oh yeah, no familiarity in sculpting or working with clay. He set out to do something that he had no idea if he could even pull off. But an obsession is an obsession, so as Goldstein explains “I had a picture in my head of what I wanted, so I grabbed the clay and just started doing it.”

After two months of “just doing it,” Goldstein had a 10-inch long scale model of a concept car inspired by the first and second generation Corvette Stingray.

By itself, that would have been a pretty impressive achievement. However, once the model was done, Goldstein had another problem. Permanence. Because he had neither the money nor the tools to handle the specialty clay used by automakers for car modeling, he had used a commercially available sculpting clay that didn’t have the permanence he needed. After all, the model needed to hang around at least three or four years, until Goldstein applied to design school, and then survive being handled by others for portfolio review. You don’t want your portfolio coming apart in someone’s hands. That’s when the young designer started his next phase of self-teaching: finding a way to turn his clay model into a more robust portfolio piece. Over the next six months Goldstein researched and learned to converse with vendors on technologies he had never heard. It probably surprised the heck out of the sales staff of several CNC, scanning, and rapid prototyping companies when this high-school sophomore called them for quotes.

If you ask Goldstein what he learned from the process of starting from a lump of clay (a material he had never touched before) and ending up with a finished prototype (using a technology he had never heard of before), a project that took him eight months from start to finish, you might expect him to talk about all the cool technologies he learned about: 3-D scanning, 3-D printing, reverse engineering tools, CAD, and so forth.

But, no.

“Patience,” says Goldstein. “I’m pretty much into instant gratification and so I learned a lot about patience.”

And where is Goldstein’s car now?

“Right now it is on my desk,” he says. “Sitting there and being awesome. But it will be part of my portfolio for design school.” Goldstein has yet to apply for college (the Art Center is typically entered as a graduate program) but will be taking his SATs soon.

Certainly, it thrills me to see teenagers like Goldstein chart their own destiny. There is no doubt in my mind that he will succeed in whatever direction he goes. But what about the other Goldstein’s out there—talented, potential art, technology, or design enthusiasts—who don’t have the type of support and confidence that Goldstein has?

We need more mentors. If the schools can’t take up the mantle of preparing and encouraging those who have a desire to excel in a field, then industry must. We need companies to keep their eyes open for teenagers like Goldstein and support them, to take them under their wing. By the way, Goldstein hinted that GKS gave him a pretty good discount on their services. And so they should. I applaud them for it.

Helping students is something that Quality Digest also feels strongly about. For our own part, we just brought on a self-motivated intern, Aly Fields, who advanced her employment opportunities by taking it upon herself to earn a Six Sigma Yellow Belt and is now working toward a Green Belt. We’re helping her along by making sure she gets a lot of exposure to industry experts and that they get exposed to her. She will be blogging her experiences for us. Read her first blog here.

There are a lot of bright young students out there who can succeed if given the support. Imagine if every company in the United States, big or small, helped just one student a year inch toward his or her goal. Wow.