Title of Presentation: Advanced Hypersonic Entry Guidance for Mars Pinpoint Landing

Primary (Corresponding) Author: Kenneth D. Mease

Organization of Primary Author: University of California, Irvine CA

Co-Authors: A. H. Salama, G. Sohl, M. Ivanov, J. A. Leavitt, J. Benito, J. Casoliva, A. Saraf, and S. Talole


Abstract:  Hypersonic entry guidance technology is being developed to support a broad range of future Mars missions. The goal is to develop guidance technology that, in conjunction with other entry, descent, and landing (EDL) technologies, will allow greater landing accuracy as well as access to higher elevation landing sites than currently achievable. The guidance technology should be applicable to capsule-type landers, but also higher lift-to-drag (L/D) configurations that will be required for landing higher mass and volume payloads. Relative to low L/D landers, higher L/D landers allow more shaping of the hypersonic entry trajectory for reduced aerodynamic loads, reduced thermal loads, and more desirable parachute deployment conditions. Higher L/D landers also have larger footprints of potential landing sites. Precise landing reduces the requirements for ground mobility by allowing payloads to be delivered where they will be used; mass not required for mobility can be devoted to science. The capability to land at higher elevation sites will make much more of the planet accessible.

The paper describes a hypersonic entry guidance algorithm developed for Mars pinpoint landing and extensive simulation results characterizing its performance for a low L/D capsule and a mid L/D lander. The guidance algorithm is based on the concept of planning and tracking drag, and extends the state of the art represented by the entry guidance algorithm of the Space Shuttle Orbiter. The algorithm has been tested in simulated flight for many off-nominal situations. The results demonstrate the effectiveness and versatility of the guidance algorithm. The guidance technology is also applicable for landing missions to other atmosphere-bearing planets and satellites.