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Real-time approximate optimal guidance laws for the advanced launch systemAn approach to optimal ascent guidance for a launch vehicle is developed using an expansion technique. The problem is to maximize the payload put into orbit subject to the equations of motion of a rocket over a rotating spherical earth. It is assumed that the thrust and gravitational forces dominate over the aerodynamic forces. It is shown that these forces can be separated by a small parameter epsilon, where epsilon is the ratio of the atmospheric scale height to the radius of the earth. The Hamilton-Jacobi-Bellman or dynamic programming equation is expanded in a series where the zeroth-order term (epsilon = 0) can be obtained in closed form. The zeroth-order problem is that of putting maximum payload into orbit subject to the equations of motion of a rocket in a vacuum over a flat earth. The neglected inertial and aerodynamic terms are included in higher order terms of the expansion, which are determined from the solution of first-order linear partial differential equations requiring only quadrature integrations. These quadrature integrations can be performed rapidly, so that real-time approximate optimization can be used to construct the launch guidance law.
Document ID
19890066679
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Speyer, Jason L.
(Texas Univ. Austin, TX, United States)
Feeley, Timothy
(Texas Univ. Austin, TX, United States)
Hull, David G.
(Texas, University Austin, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Subject Category
Astrodynamics
Meeting Information
Meeting: 1989 American Control Conference
Location: Pittsburgh, PA
Country: United States
Start Date: June 21, 1989
End Date: June 23, 1989
Accession Number
89A54050
Funding Number(s)
CONTRACT_GRANT: NAG1-945
Distribution Limits
Public
Copyright
Other

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