March 30, 2018
Each year the Graduate School at The University of Texas at Austin awards continuing graduate students competitive research fellowships in the amount of $28,000. Faculty advisors nominate students who have demonstrated important and innovative academic research. This year, three graduate students from the Department of Aerospace Engineering and Engineering Mechanics received continuing research fellowships for their ingenuity and creative problem-solving.
Daiju Uehara
In a world where swarms of quad-copter shaped drones perform in synchronized light shows and startup companies use rotors to turn flying cars from science fiction to reality, it’s important to understand the delicate balance of how helicopter blades transform during rotation.
Advised by associate professor Jayant Sirohi, Daiju Uehara who is working toward his Ph.D. in aerospace engineering, focuses his research on understanding helicopter rotor blade behavior and developing a new method for experimentally investigating shape changes in the blade’s rotation. Traditional measurement techniques require the installation of sensors on a blade. Uehara and other members of Sirohi’s research group applied a non-contact optical measurement technique called Digital Image Correlation (DIC), which photographs a number of images of an object surface and correlates these to compute its deformation, to rotating helicopter blades. Their design has already proven successful in measuring the blades of a 2 m-diameter lab-scale coaxial counter-rotating helicopter as well as an extremely flexible rotor concept, whose rotor cannot be measured by conventional methods.
Uehara’s ultimate goal for his research is to create an algorithm or methodology to reconstruct the aerodynamic forces acting on helicopter blades from structural response data using DIC instead of the more expensive conventional method of using on-blade sensors to test a rotor.
Kirsten Tuggle
While some students shoot for the stars, aerospace engineering graduate student Kirsten Tuggle has her eyes on other objects in the sky. Tuggle is spending the next year tracking satellites and space debris orbiting Earth. She said the goal of her research is to prevent satellites from colliding with each other and with the International Space Station.
Tuggle’s research involves rigorous mathematical calculations as well as developing code and simulations for tracking space debris from the ground. She said the most difficult part of her work is factoring in and quantifying uncertainty.
“The challenge is that you want to do this very accurately and since it is performed on the ground, there does exist more computational power available than that provided by an on-board computer,” Tuggle said. “But at the same time, there are tens of thousands of these objects orbiting our planet, so it has to be this balance between efficient computation, accurate state estimation, and uncertainty quantification.”
Advised by professor Maruthi Akella and assistant professor Renato Zanetti, Tuggle hopes to apply real space traffic data to her research once it is completed as well as contribute to autonomous navigation for space vehicles in the future.
Masoud Behzadinasab
Third year engineering mechanics Ph.D. candidate Masoud Behzadinasab is spending the remainder of his time as a graduate student exploring new theories in peridynamics – a relatively recent mathematical theory in mechanics for analysis of material behaviors, well-suited to modeling cracks and fracture growth.
Advised by associate professor John Foster, Behzadinasab will improve upon his previous work, investigate capabilities of some of the recent peridynamic theories, and seek for more robust constitutive models in peridynamics. His work will propose new mathematical frameworks, eventually implemented in computer codes and simulations, creating cost effective and more accurate ways of predicting how a material will respond to stress.
Because crack modeling has remained a common challenge and peridynamics has shown great potential in predicting crack growth, Behzadinasab believes his work will transcend an array of scientific disciplines.
“It’s sort of a generic problem so it’s not just limited to metals,” Behzadinasab said. “It can be applied to anywhere that fractures can happen for example in bones or in many structures. It has a lot of applications and I hope to see the impact of my work in many industries from mechanical companies to technology to the medical industry.”
