Accession Number : AD0860126

Title :   Improved Initial Value Estimates for Minimum-Fuel Orbital Transfers.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Gill, Daniel E. ; Wambold, Gary D.

Report Date : APR 1969

Pagination or Media Count : 226

Abstract : A method is developed for computing improved initial-value estimates for minimum-fuel transfer trajectories between coplanar, elliptic orbits with a thrust-limited, variable-mass rocket moving in an inverse square-law gravitational field. The initial and final orbits are specified by their eccentricities, semilateral recta and arguments of pericenter and the entire transfer consists of two finite-thrust phases. Estimates for the parameters of the optimal transfer trajectory are provided by the two-impulse solution and the techniques presented in this study provide good estimates for the unknown initial values of unspecified control, state and adjoint variables which are required to successfully compute the minimum-fuel transfer trajectory between specified orbits. (Author)

Descriptors :   *SCIENTIFIC SATELLITES, *TRANSFER TRAJECTORIES, *FUEL CONSUMPTION, MATHEMATICAL ANALYSIS, ORBITS, BOUNDARY VALUE PROBLEMS, EQUATIONS OF MOTION, ERRORS, MATHEMATICAL MODELS, SUBROUTINES, COMPUTER PROGRAMS, GRAVITY, THESES.

Subject Categories : Unmanned Spacecraft
      Spacecraft Trajectories and Reentry

Distribution Statement : APPROVED FOR PUBLIC RELEASE