Summer 2016

Teeing Off

Golfers know that the wind can be a fickle factor. On any given day, a golfer can strike a ball with the same force but have dramatically different trajectories—depending on wind conditions and course topography. Wouldn’t it be nice to have a handy cellphone app that could gauge local wind conditions and predict a ball’s trajectory?

That’s the daydream of one of the world’s leading authorities on computational fluid dynamics, Rajat Mittal, a professor of mechanical engineering and self-described “recreational golfer.” Mittal has analyzed everything from how blood flows through the heart to why the dolphin kick of swimmer Michael Phelps is so efficient. So when the opportunity arose, he teamed up with visiting postdoc Neda Yaghoobian to explore this perplexing problem.

The co-inventors have filed for a patent on golf ball trajectory prediction mapping software that can display the predicted path of a ball, taking into account wind effects, local topography, and golf ball aerodynamics. This technology promises to give golfers, coaches, sports commentators, equipment manufacturers, and others a way to predict how wind conditions could affect a ball’s flight.

Smart Catheters

Moving catheters through blood vessels is crucial for many lifesaving procedures. But doctors often have to rely on X-ray fluoroscopy for guidance, exposing patients and practitioners to radiation. Inspired by the sensing abilities of electric fish, computer scientist Nassir Navab and mechanical engineer Noah Cowan are working on a catheter using bioimpedance (the electric properties of blood and tissue) to measure blood vessels from the inside out.

Before a procedure, a CT scan helps construct a model of the vessel, including predictions of that vessel’s bioimpedance at each point the catheter will traverse. During the procedure, the system aligns the measured and predicted bioimpedance signal, thereby determining the catheter’s position within the vessel. “This system provides the physician with a real-time estimate of the catheter’s location as it moves through the vessels, without the need for harmful radiation,” Cowan says.

Superlight, Superstrong Material

Carbon fiber is a high-strength material matching steel, but much lighter. But it is expensive, energy-intensive, and polluting to produce. A typical carbon-fiber auto body might weigh 80 percent less than a typical car and use less fuel—but it could be twice as expensive to make.

Jonah Erlebacher, chair of the Department of Materials Science and Engineering, is pushing to reduce those costs. Today, carbon fiber production is a multistep process: Researchers start with fossil fuels, turn them into polymer threads, and process these polymer threads at extremely high temperatures, throwing off lots of volatiles.

Erlebacher’s lab is simplifying this process by taking fossil fuels, such as natural gas, and directly converting them to carbon fiber without any polymer intermediate. In addition, the process is powered by hydrogen released from the fossil fuel, eliminating the polluting carbon dioxide byproduct and increasing manufacturing efficiency. The process uses a metal salt as a reactant intermediate that is recycled during the process. The upshot: This process may one day pave the way for lighter, more fuel-efficient cars, airplanes, and other products.