摘要: This study investigates minimum-time rendezvous trajectories and thrust control profiles for an upper stage vehicle of the Space Transportation System. A numerical technique is presented to solve the nonlinear two-point boundary v... 展开 This study investigates minimum-time rendezvous trajectories and thrust control profiles for an upper stage vehicle of the Space Transportation System. A numerical technique is presented to solve the nonlinear two-point boundary value problem associated with the finite-thrust time-optimal trajectories. This method serves to reduce the associated computer burden through the use of a general-purpose subroutine developed by the mathematician M.J.D. Powell to solve a system of nonlinear equations. The general technque uses a gradient-type iteration when poorer estimates of the unknowns are encountered and, yet, switches automatically to the more rapid convergence of a Newton-Raphson scheme as the estimates are improved. The discontinuities associated with the on-off thrust control are overcome through an iterative determination of the related switching times. 收起