June 23, 2021

photo of matthew asper on ut campusMatthew Asper, an aerospace engineering Ph.D. student at The University of Texas at Austin, has been awarded the highly competitive National Defense Science and Engineering Graduate (NDSEG) Fellowship for 2021. Established by the U.S. Department of Defense (DoD) in 1989, the three-year fellowship is intended to promote education in science and engineering disciplines relevant to the DoD mission. Less than 10% of applicants are selected for the award, which pays for the cost of tuition and includes a monthly stipend and funding for professional development, travel and health insurance.

Asper, who is advised by Jayant Sirohi, a professor in the Department of Aerospace Engineering and Engineering Mechanics, was selected for his work on a novel vertical flight aircraft configuration. Learn more about Asper’s work and plans for the future.

Tell us about the research you are doing that is being supported by this award.

The NDSEG fellowship will support research investigating a novel vertical flight aircraft configuration. The concept involves the use of two helicopter rotors stacked on top of each other, each driven by independently-controlled electric motors. The novelty of the concept is shown by the ability of this system to change thrust in-flight via modifying the geometry of the stacked rotor blades, or more specifically the rotor-rotor azimuthal spacing. This is believed to produce less power requirements to vary total rotor thrust than a traditional speed control scheme. The significance of this is shown since a greater importance has been placed upon electrically-powered aircraft due to their improvements in sustainability versus combustion driven vehicles. However, electric aircraft suffer from decreases in power-density from batteries, so this concept may facilitate their use within aviation by requiring less power from the engine to vary thrust. This research includes both modeling and experimental testing to predict and validate the performance of this unique aircraft concept. 

photo of rotor test stand
Photo: The stacked rotor test stand mounted outside at Pickle Research Campus. The test stand is configured with a single electric motor driving two sets of two-bladed rotors, which are two meters in diameter.
What are some practical applications of this work?

Electrically-powered helicopters which are widely used in military and commercial applications such as drone delivery services and personal air mobility/air taxis.

What are your plans after you graduate?

I hope to continue researching state-of-the-art concepts integrating electric power into vehicles within the aerospace or related fields. Improvements in battery and electric motor technologies put our industry in a great position to take advantage of these systems and reduce the environmental impact gas-driven vehicles have. I plan to enter industry or a national laboratory performing research and design following graduation.