User:Egm6341.s10/Seminars

Tuesday, March 30, 2010

4:00 pm

in Room 303 MAE-A

Orbit Architectures to Support Lunar Communications from the Perspective of Multi-Body Dynamical Analysis

Professor Kathleen Howell

School of Aeronautics and Astronautics

Purdue University

Abstract

In recent years, autonomous and manned exploration studies have focused on the Moon. Communications satellites are an important component of long-duration surveillance and manned exploration missions. A proposal for a potential facility at the lunar south pole has prompted studies of orbit architectures to ensure adequate coverage options with a minimum number of spacecraft. Generally, the focus is deployment of at least two spacecraft for complete coverage. Constant communications can be achieved with two spacecraft in different combinations of Earth-Moon libration point orbits. Halo and vertical families, as well as other orbits near L1 and L2 are investigated. But, potential orbits for continuous surveillance of the lunar south pole with just one spacecraft, employing low-thrust or a solar sail, are also a consideration. Periodic orbits are first computed in the Earth-Moon restricted three-body problem, using Hermite-Simpson and seventh-degree Gauss-Lobatto collocation schemes that are then adapted to include path constraints favorable for lunar south pole coverage. Feasible trajectories can then be transitioned to higher fidelity models. Various options are investigated, noting that orbits near the Earth-Moon L2 point yield the best coverage results.

Biography

Professor Kathleen Connor Howell is presently the Hsu Lo Professor of Aeronautical and Astronautical Engineering at Purdue University; she has been a member of the faculty at Purdue since 1982. In that capacity, she maintains an active research program that includes technical publications in the areas of spacecraft trajectory design and optimization as well as maneuver strategies for transfers and on-orbit operations. As a principal investigator, she has obtained numerous grants and received various awards related to her research program including the Dirk Brouwer Award from the AAS. She was also honored with the Breakwell Award at the Astrodynamics Symposium of the International Astronautical Congress and invited to give the Memorial Lecture at the 2007 IAF Congress in Hyderabad, India. She teaches both undergraduate and graduate courses at Purdue and has received a number of national awards for excellence as an engineering educator. Dr. Howell is also active in a number of professional societies. Currently the Editor-in-Chief of the AAS Journal of the Astronautical Sciences, she previously served as Managing Editor for the journal. She has been a member of the AIAA Astrodynamics Technical Committee and the Astrodynamics Committee of the International Astronautical Federation. She is currently a member of the AAS Space Flight Mechanics Technical Committee. She regularly attends the IAC as well as AIAA and AAS technical conferences. She earned her BS degree in Aerospace Engineering from Iowa State University; her MS and Ph.D. degrees in Aeronautical and Astronautical Sciences are from Stanford University.

Refreshments served in 303 MAE-A beginning at 3:50 pm