Perry Parks made a big impression on the folks interviewing him at Siemens PLM about four years ago, his colleague Altaf Arsiwala recalled. As Parks described his master’s thesis—“Translational Damping on High-Frequency Flapping Wings”—he at one point leapt to his feet and flapped his arms to illustrate a concept. He was hired on the spot.
Parks earned an integrated master’s in mechanical engineering in five years at Purdue. That was another reason Arsiwala felt sure Parks could handle the tons of code and variety of concepts he would be exposed to in the first couple of years in the Assembly Modeling area in NX.
“Right from the start Perry demonstrated an instinctive talent for developing Mechanical CAD software,” he said. “He was unfazed by the complexity, and we were able to trust him with design and project leadership responsibilities towards the end of his first year.”
The research Parks took on at Purdue involved “bio-inspired robotics,” he said: “Taking cues from nature on how it had solved some of the biomechanical problems of locomotion.” Others at the school had developed a micro-air vehicle (MAV) flapper mechanism that resembled a cicada—for which they needed to design a control system.
To get there, they first needed Parks’ help studying the system dynamics: “We needed to understand the physical dynamics of the system before we could move on to using that information in a control loop in the electronics. So I worked on investigating what type of damping, or resistance, the cicada-size vehicle would encounter when moving through the air (and not rotating) while flapping its wings.”
He found that an MAV flapping in a vertical hovering orientation while moving through the air produced more drag than if it were just gliding in the same orientation. “You could imagine that, but you wouldn’t necessarily expect it—because the wings are pushing forward in one direction and backward in the other direction as it’s translating forward,” he said. “But it doesn’t completely cancel out.”
The data is helpful because it helps engineers create more inherently stable systems. “If you’re flapping in a hovering orientation and a wind gust hits you, it turns out that even without actively working to compensate for the gust you will already have a bit of natural resistance to this type of disturbance.” And such systems are what’s needed for autonomous flight.
Using CAD software, Parks built a test apparatus—a mounting point with a bracket and some ball bearings—and suspended a pendulum from it. He mounted the flapper mechanism on the end of the pendulum and set up the system so it could oscillate back and forth while flapping in order to measure drag.
He reached his goal of recording a drag coefficient that matched an existing theoretical model. And that, he said, means engineers can now more easily calculate the drag for such MAVs by measuring the geometry of the flapper and using existing equations—saving time in the lab.
Today, he is involved in the design of CAD software tools that let people design similar objects.
He loves variety. Projects he’s been able to work on include functionality to mirror an assembly of parts and clearance analysis—“when you have parts that are intersecting, we can use mesh geometry to make measurements that determine how far one object penetrates into another,” he said.
This article was first published in the July 2016 edition of Manufacturing Engineering magazine. Read all of the 2016 30 Under 30 Profiles as a PDF.