2026-09-20T20:28:28Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/110395 2023-07-11 col_2142_5131 com_2142_5130

Prussing, John E. Prussing, John E. Scott, Edward J. Hilton, Harry H. Conway, Bruce A. Heckathorn, William G. 2021-09-14T18:21:17Z 2021-09-14T18:21:17Z 1985-08 A method for determining the optimal impulsive trajectories is applied to minimum fuel, direct ascent, time-fixed intercept trajectories. The optimal trajectory is obtained by satisfying Lawden's necessary conditions expressed in terms of the primer vector. The vehicle is initially at rest on the surface of a spherical planet and the target is assumed to be in a circular, equatorial orbit around the planet. Results are presented and compared for two planetary models: a non-rotating planet, and one rotating with an angular velocity approximating that of the Earth. Each model is investigated for transfers in which the launch point is in the same plane as the target orbit (coplanar) and in which the launch point is not in the target orbit plane (noncoplanar). Parameters varied during the analysis include transfer time, target radius, initial position of the target in relation to the launch point, the latitude of the launch point, and the direction of the transfer trajectory, i.e. posigrade or retrograde. Cost comparisons are made between various cases, and generalizations indicated. Open Restriction set for Item 118214 on 2021-09-14T18:09:00Z with date null by eliasbh2@illinois.edu. Submitted by Eli Hubbard (eliasbh2@illinois.edu) on 2021-09-14T18:21:17Z No. of bitstreams: 1 9988658912205899.pdf: 19707695 bytes, checksum: 5171b1111108f8cc03842728bf96b886 (MD5) Made available in DSpace on 2021-09-14T18:21:17Z (GMT). No. of bitstreams: 1 9988658912205899.pdf: 19707695 bytes, checksum: 5171b1111108f8cc03842728bf96b886 (MD5) Previous issue date: 1985-08 Open http://hdl.handle.net/2142/110395 en Astronautical Engineering Optimal, impulsive, direct ascent, time-fixed orbital interception dissertation/thesis text Department of Aerospace Engineering Aeronautical and Astronautical Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D. (doctoral) Ph.D in Aeronautical and Astronautical Engineering