AEM Seminar Series: Zachary Putnam

Zachary R. Putnam, a NASA Space Technology Research Fellow and Ph.D. candidate in aerospace engineering at the Georgia Institute of Technology, will be speaking as part of the Aerospace Engineering and Mechanic’s Research Seminar Series on “Integrated Design and Analysis of Guidance, Navigation, and Control Systems for Hypersonic and Space Systems”.


The increasing complexity of hypersonic systems requires integrated analysis of guidance, navigation, and control (GNC) systems to better understand subsystem interactions early in the design cycle to improve system performance and assess program cost. In this presentation, an integrated, GNC-focused analysis of drag modulation as a means of hypersonic trajectory control is discussed, followed by a comparison of lift and drag-modulation trajectory control systems. Drag modulation is shown to be an effective means of trajectory control that is potentially simpler than current state-of-the-art lifting systems. Mars Science Laboratory-class downrange errors are shown to be achievable with a dragmodulation entry, descent, and landing architecture. Analytical approximate solutions to the equations of motion are used to assess and compare lift and drag-modulation trajectory control schemes, resulting in design guidelines that may be used to inform system selection early in the design cycle. A research campaign is proposed to improve integrated GNC system design and performance through application of multidisciplinary design and optimization techniques to algorithm and mission design, modeling and simulation, flight software, and GNC hardware; these integrated analyses have application across a broad range of aerospace systems.


Zachary R. Putnam is a NASA Space Technology Research Fellow and Ph.D. candidate in aerospace engineering at the Georgia Institute of Technology. His Ph.D. research focuses on developing and comparing disparate trajectory control systems for planetary entry and aerocapture vehicles. His research interests include hypersonic and space systems, GNC systems, flight software, and design optimization. Before returning to academia to obtain his Ph.D., Mr. Putnam was a senior member of the technical staff at the Charles Stark Draper Laboratory where he was task leader for the entry guidance algorithms for NASA’s Project Orion. He earned an M.S. in Aerospace Engineering in 2006 and a B.S. in Aerospace Engineering in 2004, both from the Georgia Institute of Technology.