Seminar: Analysis vs Simulation or Brains vs Computers - Oct. 17

Terry Alfriend
Professor, Aerospace Engineering, Texas A&M University
Friday, Oct. 17 | 10:40 A.M. | AERO 111

Abstract: The significant advances in computational technology now allow us to perform detailed simulations of complex systems. Accompanying this advancement has been a reduction in the cost of developing many systems. Many wind tunnels have been shut down due to the advances in CFD and aircraft simulators/emulators have reduced the cockpit training time for pilots.   Our students can now solve much more complex problems in class and in their theses.  Accompanying these advances in computational capability has been a trend to total reliance on simulations, and not performing the analytical work to develop approximate analytic solutions to problems that can provide significant insight into the physics of the problem.   Approximate analytical solutions can also help in validating the software and performing sensitivity studies, which helps reduce costs. In this seminar the value of approximate analytical solutions to complex problems will be demonstrated with three examples, estimation of the space object population and distribution, the tracking of mobile missiles, and control of a satellite formation that maintains the relative motion orbit while minimizing total system fuel consumption and balancing the fuel use over all the satellites in the formation.

Bio: Terry Alfriend is currently the Professor and Holder of the Jack E. & Francis Brown Chair II of Aerospace Engineering at Texas A&M University and a University Distinguished Professor. He has over 55 years of diverse experience in the aerospace business that includes research, development and management in the private sector, government, and academia.  He is a member of the NAE, an Honorary Fellow of the AIAA, a Fellow of the AAS and a member of the International Academy of Astronautics.  He has served as an Associate Editor and Editor-in-Chief of both the AIAA Journal of Guidance, Control and Dynamics and the AAS Journal of the Astronautical Sciences and the.  He is also the recipient of the AIAA Goddard Astronautics Award, the AIAA Mechanics and Control of Flight Award, the AIAA Guidance, Navigation and Control of Flight Award, and the AAS Dirk Brouwer Award. His research interests are in space domain awareness, astrodynamics, satellite attitude dynamics and control and spacecraft design. Recently he had a minor planet named after him (5963) Terryalfriend = 1990 QP2. He is a co-author of two books:  Spacecraft Formation Flying: Dynamics, Control and Navigation, Alfriend, Vadali, Gurfil, How and Breger, Elsevier 2010 and just published History of Space Surveillance and Satellite Cataloging: A Long and Winding Road. Schumacher, Hoots and Alfriend, AIAA, Sept. 2025.