New Faculty Profile: Brian Mann
Not long ago, while taking a walk and bemoaning the fact his cell phone kept dying, Brian Mann had an inspiration. “I know I walk enough to recharge my cell phone,” he thought. “Now I just need to find a way to turn that motion into energy.”
The idea of exploring everyday activities or natural phenomena as novel sources of energy, known as energy harvesting, is the newest research interest for Mann, who joined the faculty of Duke University’s Pratt School of Engineering this academic year as assistant professor in the Department of Mechanical Engineering and Material Science.
This line of research is a logical offshoot to his primary interest in nonlinear dynamics - a research area that investigates the stability behavior of natural phenomena and the evolution of systems in nature. While non-linearity can be found in virtually every engineered and natural system, Mann said “linear models are often applied for analytical convenience although they suffer from elucidating the true behavior. Thus the ability to understand, control, and take advantage of nonlinear behavior provides a complementary set of tools to address modern engineering problems.
“Researchers have been studying energy harvesting devices that operate in linear regimes, however we’re interested in using non-linearity as a way to take advantage of what’s happening in nature,” Mann continued. “We want to integrate sophisticated theory into novel experimental devices that extract environmental energy through vibration and turn this mechanical energy into usable electrical energy.”
This Missouri native already has three undergraduate students working on the development of devices to capture these everyday motions and turn them into energy. He hopes to start testing devices this spring.
Recognizing his potential in the field of energy harvesting, the Office of Naval Research named Mann one of 24 promising young researchers in the nation for 2008 in its Young Investigator Program. He was one of nine investigators awarded grants in the Sea Warfare and Weapons section of the program. The three-year program awards grants of up to $100,000 per year.
The title of his proposal, “Broadband Energy Harvesting in Varied and Uncertain Environments,” belies the nature of his proposal – developing buoys that harvest the energy in ocean waves to power a network of sensors.
“We proposed a scientific investigation that takes into account the challenges of real ocean environments, such as wave height and frequency and wind speeds, all of which can change considerably in a short period of time,” Mann explained. “The project includes the design, fabrication and testing of these buoy energy harvesters. Experiments will first be performed in the lab, before moving to a wave tank and finally the ocean.”
Mann also continues to apply his skills in the aerospace field, most recently with Boeing, where he has worked to develop stability and vibration prediction techniques that are being used to machine aircraft structures that are lighter in weight, yet more durable. As an example, his work is being implemented to increase the dimensional accuracy of thin wall structures used in spacecraft and unmanned aircraft. In 2006, Mann received a Defense Manufacturing Achievement Award for his work in this area.
In a similar vein, Mann has helped to develop techniques that determine the material behavior of thin films and surface coatings. “When there are layers in a composite material, it can be difficult to test the properties of the thinnest, topmost layer. These layers may have different properties than the underlying layers, and we need to know this to better understand whether the surface and not just the bulk material can withstand certain stresses.”
This work was supported by the National Science Foundation.
Mann’s journey to Duke has taken a number of varied turns. After graduating from high school, he enlisted in a two-year hitch in the United States Air Force at Dyess Air Force Base outside Abilene, Texas. He then earned a B.S. degree in mechanical engineering – the first family member to graduate from college – from the University of Missouri. He stayed in the Show Me state – earning an M.S. degree in mechanical engineering design and a D.Sc. degree in mechanical engineering, both from Washington University.
He came to Duke after spending five years in the aerospace and automotive industries to take advantage of the opportunities offered by an academic setting, particularly Pratt faculty and the students.
“There are world-class experts here in my field to collaborate with,” he said. “Also attractive was the opportunity to do interdisciplinary work with groups of researchers whose work transcends traditional engineering. Just as important was the chance work with students who will be future leaders in our field.”
For someone who is so immersed in such intricate and precision matters, it might be surprising to learn that Mann spends much of his non-engineering time in his woodworking shop using traditional hand tools to build furniture, such as rocking chairs and roll-top desks.
“It’s an artistic and creative outlet, and it is something I can do with my two young boys,” he said, referring Dillon and Drake, four and seven respectively. “Together, we’re involved in what will someday become family heirlooms. It is also an example to them that they can do anything they want if they set their mind to it.”