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Indexed by:Journal Papers

Date of Publication:2016-01-01

Journal:JOURNAL OF AEROSPACE ENGINEERING

Included Journals:SCIE、Scopus

Volume:29

Issue:1

ISSN No.:0893-1321

Key Words:Circular restricted three-body problem (CRTBP); Libration-point orbit; Time-varying controller; Finite time; Parameter optimization; Weighting matrix

Abstract:An improved time-varying optimal controller based on parameter optimization is proposed for the stabilization of spacecraft missions on nominal libration-point orbits of the Sun-Earth system. Because of the importance of the weighting matrices in the design of the time-varying controller, based on a genetic algorithm and the sequential quadratic programming method, two optimization models (for time-invariant and piecewise-constant weighting matrices) are used to determine the weighting matrices to improve the performance of the time-varying optimal controller. Practical missions are presented for a spacecraft moving steadily on a reference orbit. Numerical simulations of these missions demonstrate that the parameter-optimization methods provide a smaller overshoot and faster convergence time than when trial-and-error or Bryson's rule are used to select the weighting matrices. Piecewise-constant weighting matrices calculated for the time-varying controller using the parameter-optimization method provide better control performance than time-invariant weighting matrices. Additionally, for both optimization models, the genetic algorithm combined with sequential quadratic programming produces a shorter injection period and lower fuel consumption than the other optimization methods that are compared in this paper. (C) 2015 American Society of Civil Engineers.