Leading the Way in Navigation Research

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Maps have always fascinated Dorota Grejner-Brzezinska, a professor of civil and environmental engineering and geodetic science. She considers maps — particularly old ones — pieces of art.


Dorota Grejner-Brzezinska
As an undergraduate student studying surveying and geodesy at Agricultural and Technical University of Olsztyn, Poland, Grejner-Brzezinska read professional journal papers about GPS and decided she wanted to study it more. But the technology was not yet available in Central Europe.“Since prehistoric times, people have been trying to figure out a reliable way to tell where they are, guide them to where they are going and get them back home again,” says Grejner-Brzezinska. “When I first chose to study surveying in college, I wanted to learn how maps are made. I never expected that I would end up working on algorithms and methods for map making from space satellites!”

“Everybody close to or related to geodetic science at that time knew Ohio State was the world capitol of geodetic science and had been a stronghold in the field since the 1950s,” says Grejner-Brzezinska.

So in 1990, she came to Ohio State on a Fulbright scholarship to earn master’s and doctoral degrees, and in 1995 she joined the Ohio State Center for Mapping and, subsequently, in 1998, College of Engineering faculty. Recognized nationally and internationally for her work in the science of navigation, she established the Satellite Positioning and Inertial Navigation (SPIN) Laboratory at Ohio State.

Her research has spanned continents. Her work has taken her to remote areas of Australia and Brazil, and she participated in a San Andreas Fault mapping mission in 2005. With the U.S. Geological Survey and an Ohio State geology team led by earth sciences Professor Terry Wilson, Grejner-Brzezinska in 2002 traveled to McMurdo Station in Antarctica, where the team set up a network of GPS receivers on bedrock to estimate the post-glacial rebound, or vertical uplift of the continent due to melting ice.

“I was extremely impressed with the breadth and scope of research in Antarctica. Performing research in one of the most beautiful places on earth is a privilege, and I felt very fortunate to work with world-class researchers and to be one of not so many to set my foot at the bottom of the world,” says Grejner-Brzezinska.

Since then, she has worked with SPIN Lab colleagues and students on a research project sponsored by the National Geospatial-Intelligence Agency to develop a personal navigation system that uses GPS technology with micro-electro-mechanical inertial navigation technology, a miniaturized barometer, digital compass and human locomotion model (i.e. step length and direction).

“By nature, personal navigation systems require constant research, as the technology keeps improving. We’re trying to extend the duration of reliable navigation and expand its coverage to GPS-denied environments, so the system is still being perfected,” says Grejner-Brzezinska.

Her current research explores the concept of collaborative navigation, which allows a networked group of users to navigate when GPS signals are not available or become jammed, such as in urban, underground, underwater or indoor environments. Collaborative navigation bridges gaps in GPS availability by using inter-nodal ranging measurements, inertial measurements and algorithms to find the distance and angle of an object or person.

In cases of limited signal availability, ground soldiers could use collaborative navigation to determine the exact locations of fellow soldiers. If each soldier represents a “node,” a master node can combine all available GPS signals and pass them onto the sub-nodes. And emergency rescue workers, such as dive teams who might not have GPS signals under water, also could benefit from the technology.

“The next frontier for the collaborative navigation research field includes real-time capabilities and layered sensing,” says Grejner-Brzezinska. “A layered sensing model would combine underwater, ground, air and space mapping to provide a ‘system of systems.’”

Contact:
Dorota Grejner-Brzezinska, (614) 292-8787, grejner-brzezinska.1@osu.edu

Category: Faculty