Switch in Research Focus Inspires Mechanical Engineer Kurt Wulff



By Claire Cusick



Kurt WulfYou might think that graduate school is all about specialization – continually narrowing your field to study a smaller subject in greater depth.

Not so in engineering. Or, at least, not in the case of Kurt Wulff.

Wulff, who earned a B.S. in electromechanical engineering from Loras College in Iowa, came to Duke interested in studying more about controls. Controls can be devices, design tweaks or programming that regulate activities–— keeping everything in balance and functioning properly.

"Controls are used everywhere," he said. "Heating systems, cars – they’re used pretty much across the board."

His senior undergraduate project was a firefighting robot. To build it, he had to do a lot of controls work – the part of the design process that ensures the robot will do what he wanted it to do – before he even thought about the firefighting aspect. For example, the robot moved using two motors, one on each side. No two motors produce identical driving speeds, so Kurt created a control mechanism to compensate for differences in the individual drive trains and used controls to synchronize the two motors.

y you want them to," he said. "It’s like when a person sees stairs, he knows what to do. Robots don’t have that sense. You have to build it in."

To continue this type of work, he applied to the Department of Mechanical Engineering and Materials Science, and began work in a lab that focused on acoustics and vibration control.

That lab, working under the supervision of Prof. Rob Clark, changed its focus in 2002 to areas associated with nanotechnology and tools for bioscience. Now the control was focused on tiny molecules rather than large machines.

Instead of working to correct undesirable results – for example, an airplane traveling too fast makes for an annoyingly loud trip -- the lab’s researchers now want to create desirable results in nanotechnology and bioscience. Studying how things work on a micrometer-sized level is an exciting new field, and there’s much basic science to be done.

So while he’s still studying controls, Kurt is now doing it in a biology environment. In pursuing his Ph.D, his research goal is to build a state-of-the-art optical trap for use in biological materials and nanosystem investigation. An optical trap (think of it as an optical tweezer) is an instrument capable of manipulating microscopic particles using the inherent momentum of light. "Kind of like the tractor beam on Star Trek," Wulff said. (Really.)

"As we’re walking around, light is continuously exerting force on us," he said. "But it’s just so small, we don’t notice it."

But light’s force on micrometer-sized objects is not small. Wulff wants to learn, document and be able to replicate the effects of this force on molecules, with possible impact on areas in physics, chemistry, biology and engineering.

So Wulff is building an optical "trap" to manipulate microscopic particles, and study the effects of that manipulation.

"When you’re moving things, you need to know how far you’re moving them," he explained.

Right now, his research is at the stage of using the optical trap to deliver accurate measures of displacement when force is applied. Wulff needs to know the degree of force and the degree of displacement. Force applied to an object has an effect on the object, and sometimes it exceeds desired conditions. So Kurt is studying how force affects tiny biological specimens, and how much force is needed to achieve precise maneuverability.

Kurt’s interest in mechanical engineering comes from growing up on his family’s Illinois farm, where he was around a lot of large machinery – tractors, combines.

"I always wanted to know how they worked or how they could be improved," he said. "Later on I realized that engineers were the ones who build these machines, and that was what I wanted to explore."

After staying within an hour of home for his bachelor’s degree, Kurt wanted to venture farther afield for his graduate work. He looked at a map, and drew a circle whose radius was a 10-hour drive from home. He applied to Duke, Penn State and Colorado State.

When he visited in January 2001, it was warm in Durham, both in temperature and in academic environment. He thought of Duke as "a bigger name school with still a comforting atmosphere," and has found that to be true.

"With eight to ten people, our research group is larger than most. So senior members of the team provide guidance to the newer students on everything from classes and degree requirements to social outings," he said. "Professor Clark has also encourages us to enjoy our time in graduate school."

Kurt enters his fourth year this fall, and hopes to graduate in December of 2005. He would be interested in a job in either academia or industry. Having lived in the Midwest and now the East, he’s also open to exploring another area of the country.

"I’m leaning toward the Pacific Northwest next, but that could change," he said.