October 18, 2013, Webb 1100

Spacecraft atmospheric entry guidance presents a challenging control problem. It is a finite-time terminal point control problem with nonlinear dynamics, path and control constraints, and substantial modeling uncertainty. The effective strategy of planning and tracking a drag acceleration profile emerged from the U.S. Apollo and Shuttle programs. Subsequent efforts have built on this basic strategy to further improve performance and to respond to new mission challenges. Extensions for onboard trajectory re-planning, expanding the landing footprint, and enabling higher elevation landing at Mars are described. Entry guidance performance assessment results, via computer simulation, for several vehicles with low to mid lift-to-drag ratios for both Earth entry and Mars entry are presented.

Kenneth D. Mease is Professor and Associate Chair of Mechanical and Aerospace Engineering at the University of California, Irvine. He received his B.S. degree from the University of Michigan and his M.S. and Ph.D. degrees from the University of Southern California. He held positions at the Jet Propulsion Laboratory and at Princeton University before joining the faculty of UC Irvine. His research has addressed the guidance, navigation and control of aircraft and spacecraft, time-scale decomposition for nonlinear dynamical systems, and molecular control. He is an Associate Editor for the Journal of Optimization Theory and Application, and previously served as Associate Editor for the AIAA Journal of Guidance, Control, and Dynamics and the AAS Journal of the Astronautical Sciences. He was a member of the NASA Human Planetary Landing Capability Roadmapping Team in 2005. He is an Associate Fellow of the AIAA and a Member of SIAM and the SAE Control and Guidance Systems Committee.