Flexible hybrid electronics bend the rules of computing architectures

June 1, 2017

Typical computing platforms don’t bend, twist and flex the ways we humans do. Powerful silicon architectures in use today require rigidity, but the wearable, assistive and medical computing applications of the future would be most beneficial if they were flexible.

Umit Ogras, an assistant professor of electrical and computer engineering in Arizona State University’s Ira A. Fulton Schools of Engineering, is developing an innovative methodology and tools to optimize the design of flexible hybrid electronics — architectures that combine flexible elements and rigid silicon to overcome the performance limitations of purely flexible electronics. The work is supported by a $500,000, five-year National Science Foundation CAREER Award project. Portrait of Umit Ogras Umit Ogras is an assistant professor of electrical and computer engineering in Arizona State University’s Ira A. Fulton Schools of Engineering. Download Full Image

“Physical flexibility and stretchability expands the design space into an uncharted dimension,” Ogras said, “which introduces intricate trade-offs with the traditional power, performance and area metrics, but can also drive the next big leap forward in form factor design, similar to the shift from desktop and laptop computers to handheld devices.”

Purely rigid electronics like our smartphones boast high computing power but lack the flexibility required for wearables. However, flexible thin-film transistors fall short on processing power.

It’s up to electronic systems designers to figure out how to combine silicon and flexible printed electronics for better-performing, mostly flexible systems.

“However, there are no proposed solutions for the systematic modeling and design of flexible hybrid electronic systems,” Ogras said.

Ogras is taking a new approach to the problem. He is constructing new tools that quantify flexibility as a metric in the design process.

“This will enable designers to find the optimal set of rigid integrated circuits, such as state-of-the-art silicon microprocessors, and flexible/stretchable devices such as sensors, antenna and displays, that implement the target functionality,” Ogras said. “Then, the rigid ICs will be integrated onto flexible or stretchable substrates using emerging interface techniques such as those developed at NextFlex.”

Flexible hybrid electronics have great potential for wearable computing, assistive technologies, the Internet of Things, body sensors and medical applications.

This figure shows a system-on-polymer (SoP) proposal with flexible circuits, display and battery, and rigid integrated circuits, demonstrating an optimization of flexible and rigid parts to optimize performance.

Flexible hybrid electronics display the next step in form factor evolution. This figure shows a system-on-polymer (SoP) proposal with flexible circuits, display and battery, and rigid integrated circuits, demonstrating an optimization of flexible and rigid parts to optimize performance. Graphic courtesy of Umit Ogras

 “For example, flexible hybrid electronics can enable electronic patches equipped with motion, physiological and biochemical sensors, and wireless transceivers,” Ogras said. “These patches can be used to examine movement disorders at any time and anywhere, in stark contrast to the current practice, where a patient has to stay in a clinical environment.”

He hopes in the long term, flexible hybrid electronics can “deliver the functionality of current state-of-the-art mobile platforms and more in a truly pervasive form factor.”

Ogras said ASU is one of the leading institutions in the flexible electronics area, and collaborations with the Power One IC Research Center and Flexible Electronics and Display Center have greatly helped his NSF CAREER Award project development.

Monique Clement

Communications specialist, Ira A. Fulton Schools of Engineering


Study links deforestation to drug trafficking in Central America

June 1, 2017

Cocaine trafficking in Central America, a long-known and often discussed topic, is having a surprising impact — shrinking tropical forests.

A recent study, published in the journal Environmental Letters, estimates that up to 30 percent of the region’s tropical forest has been cut down and cleared out over the past 10 years as a by-product of the drug trade. A bird's-eye view of forests in Guatemala. Photo courtesy of Dennis Jarvis Download Full Image

“Drug trafficking not only affects areas where drugs are produced or consumed but also areas of transit,” according to Karina Benessaiah, a doctoral student with Arizona State University’s School of Geographical Sciences and Urban Planning and one of the paper’s co-authors.

Large, rapid forest clearings correlate with the movement of drugs through the region, particularly in Caribbean Honduras, Guatemala and Nicaragua.

“Over the same period of rapid deforestation, U.S.-led supply-side militarized interdiction drug policies that target the production and movement of drugs has pushed cartels from flying planes into Mexico and into overland, air and marine routes in Central America to move the cocaine northward,” said Elizabeth Tellman, also a co-author of the paper and doctoral student with the ASU’s School of Geographical Sciences and Urban Planning. “Interdiction pushes the movement of drugs into remote, forested regions of Central America.”

It’s not just the movement of the cocaine that is impacting the forest. The money produced from the drug trade also leaves its mark on the land. “An estimated $6 billion of illegal profit is left in Central America as a result,” said Tellman. “This money needs to be legitimized, or laundered, and it is often done so by converting forest into other land uses, like oil palm production and cattle ranching.” 

Swaths of land across the region disappearing could create irreparable changes to the ecosystem. The region, known as the MesoAmerican Biological Corridor, is home to 7 to 10 percent of the world’s endemic species. It is estimated that between 30 percent and 60 percent of the deforestation is taking place within biodiverse and internationally protected areas.  

“Drug trafficking — and the cat-and-mouse game between traffickers and law enforcement in the war on drugs — affects local people and the environment,” said Benessaiah. “Forests are lost, and that matters for conservation but it also matters because people are losing their livelihoods.”

The region is home to more than 80 ethnic groups and many impoverished farmers who depend on the land for survival. The high rate of deforestation poses a direct threat to these groups’ livelihoods and security.  

According to the researchers, the “war on drugs” has only exacerbated the issue and pushed the drug trade deeper and deeper into the forests. Their proposed solution? Environmental policy and drug policies can no longer live in silos.

“Conservation policy must be better aligned with drug policy, with the recognition that supply-side interdiction efforts may cause severe environmental damage in this biologically and ethnically diverse, sensitive region,” said Tellman.

You can read their full paper in the May 2017 issue of Environmental Research Letters.

Photo used is courtesy of Dennis Jarvis, licensed under CC BY 2.0.

Manager, Marketing and Communication, School of Geographical Sciences and Urban Planning