Technology that could help save lives of soldiers

University at Buffalo researchers Jason Corso and Natalia Litchinitser have been awarded funding from the US Department of Defense (DoD) to conduct research into technologies that could help save the lives of American soldiers.

UB computer scientist Jason Corso is engineering robots that could detect potential threats and help keep American soldiers at a safe distance.

Corso, assistant professor of computer science and engineering, and Litchinitser, associate professor of electrical engineering, each received Defense University Research Instrumentation Program (DURIP) awards for their research. The two awards total $486,250.

Corso leads a multi-disciplinary team of researchers from the University of Buffalo School of Engineering and Applied Sciences whose joint research focuses on using swarms of robots to accomplish challenging operations, such as surveillance, search-and-destroy, search-and-rescue, soldier-aid, communication chaining and terrain mapping.

UB electrical engineer Natalia Litchinitser is conducting research on how light interacts with a novel class of optical media called metamaterials.

Corso's DURIP award will fund the purchase of a fleet of mobile robots -- classified as unmanned ground vehicles in military language -- with varying capabilities to support this research. The equipment will enrich the research environment and will be used in student courses as well.

The 2001 Congressional Defense Authorisation Act stated that one-third of ground combat vehicles should be unmanned by 2015. So while the DoD already uses unmanned ground vehicles in battlegrounds such as Afghanistan, Corso's robots will take advantage of more intuitive radio controls and more acute visual detection systems.

"Unmanned and autonomous vehicles clearly have a strong potential to empower the army to better achieve its mission into the future," says Corso.

And Corso is engineering multiple types of robots designed to complement each other's strengths.

"There is no general purpose soldier in an elite fighting squad," says Corso. "Rather, each must specialise in one area so the whole is greater than the sum of the parts."

These unmanned ground vehicles – or robots – would provide their human radio-operator with sensory feedback from either line-of-sight visual observation or remote sensory input, such as video cameras. The robot's ability to detect objects of interest and potential threats, such as people or vehicles, will help keep American soldiers a safe distance from potentially dangerous situations.

Litchinitser's work involves fundamental and applied research in light interaction with a novel class of optical media – metamaterials – an artificial material designed to have properties and functionalities not normally found in nature. Meta is Greek for beyond. Impressive phenomena to be enabled by these materials are negative index of refraction and cloaking device -- a device that makes objects invisible -- a long-awaited realisation of the science fiction idea described in H. G. Wells' Invisible Man or J K Rowling's Harry Potter stories.

Metamaterial technology offers unique opportunities for engineering previously inaccessible values of refractive indices and achieving unprecedented control over light propagation.

Negative or near-zero index of refraction, subwavelength imaging, and cloaking are just a few of the peculiar phenomena and functionalities enabled by these unique structures.

Litchinitser's research focuses on the design and realisation of nonlinear ultra-compact metamaterial devices, including electro-optically and nonlinear-optically tunable components for photonic integrated circuits, nonlinear visible-IR frequency and image converters, optical limiting and pulse-shaping devices for infrared countermeasures and sensing, and light concentrators for highly efficient photovoltaic devices.

She hopes to demonstrate an ultra-compact photonic microchip enabled by metamaterials, which would be capable of much faster signal processing speeds than a traditional electronic microchip of the same size.

"With electronics you can do very small devices, but as a technology it's reaching its maximum speed," says Litchinitser. "Electronics can only be so fast."

Optical characterisation is a crucial part of fundamental studies of metamaterials properties and of the design of novel devices. Litchinitser's award will pay for a purchase of the state-of-the-art optical characterisation tool, a variable angle spectroscopic ellipsometer (VASE) system.

She will use this system to retrieve the key electromagnetic parameters of optical metamaterials essential for the realisation of functionalities at visible and near-infrared wavelengths.

Another direction of her metamaterial research is in the emerging area of transformation optics. Litchinitser, together with UB doctoral student Apra Pandey, is investigating nonlinear optical devices that enable reconfigurable optical structures that can be switched from being a light concentrator to a directional emitter to a reflector or provide scattering functionality.

Finally, they design metamaterial structures to manipulate spin and orbital momentum of the light beam. These very fundamental studies are likely to enable such important DoD applications as large depth of focus imaging systems and enhanced secure free-space communication systems.

The DoD has dedicated $37.8 million to 83 academic institutions, divided into 165 DURIP awards. The awards are expected to range from $50,000 to $990,000 and average approximately $230,000.