Accession Number:

ADA034005

Title:

An Energy Management Guidance Scheme Applicable to the Interim Upper Stage.

Descriptive Note:

Master's thesis,

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING

Personal Author(s):

Report Date:

1976-12-01

Pagination or Media Count:

165.0

Abstract:

A workable open loop guidance scheme for orbital transfer maneuvers is developed for a two stage solid-rocket vehicle which has no thrust termination capability. The scheme effectively manages any excess energy by matching a non-Hohmann transfer trajectory to the fixed energy capabilities of the vehicle. The entire burden of effecting the transfer is put on prelaunch targeting, so that during the burns the thrust can be directed along a precomputed direction using constant attitude maneuvers only. A computer program has been developed which employs a nonlinear equation solving routine to accomplish exact targeting for the finite-thrust transfer maneuver. The transfer trajectory is characterized by 6 control parameters outputs of targeting, and the final orbit is defined by a set of hit conditions. An error analysis is performed on the scheme throughout the range of possible trajectories which exist for excess energy missions. These trajectories are compared on the basis of optimality, such as minimum insertion errors and transfer time. Results are presented for geosynchronous and subsynchronous transfers between circular orbits.

Subject Categories:

  • Spacecraft Trajectories and Reentry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE