SUB-OPTIMAL CORRECTION OF SPACECRAFT TRAJECTORIES.

Abstract

The problem considered is the minimum-fuel correction of spacecraft trajectories. The presence of a nominal trajectory during the midcourse phase is exploited to represent the system by a set of linear, time-dependent, ordinary differential equations. The control is assumed to be constrained in magnitude. Both measurement and execution errors are assumed to be present so that the resulting problem is stochastic. By an application of Decision Theory, an open-loop, fuel-optimal control is derived which is continuous in nature and dependent only on the solution of a deterministic version of the problem. A sub-optimal approximation, which is on-off in nature, is presented. The sub-optimal open loop control also depends only on the solution of a deterministic version of the problem, and in addition, provides a separation property whereby the estimator and the controller can be optimized separately. In the noiseless case, the sub-optimal control reduces to the optimal deterministic control. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1968
Accession Number
AD0710325

Entities

People

  • George Parkins

Organizations

  • New York University

Tags

DTIC Thesaurus Topics

  • Decision Theory
  • Differential Equations
  • Equations
  • Estimators
  • Mathematics
  • Measurement
  • Orbits
  • Spacecraft
  • Spacecraft Orbits
  • Spacecraft Trajectories
  • Trajectories

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Control Systems Engineering.

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers