Ernest S. Armstrong

An extension of Bass' algorithm for stabilizing linear continuous constant systems

A stabilization algorithm of Bass originally developed for controllable systems is extended to include systems which are stabilizable.

A stabilization algorithm for linear discrete constant systems

A procedure is derived for stabilizing linear constant discrete systems which is a discrete analog of the extended Bass algorithm for stabilizing linear constant continuous systems. The procedure offers a method for constructing a stabilizing feedback without the computational difficulty of raising the unstable open-loop response matrix to powers thus making the method attractive for high order or poorly conditioned systems.

Series representations for the weighting matrices in the sampled-data optimal linear regulator problem

Taylor-series representations for the weighting matrices in the optimal sampled-data regulator problem are presented along with error bounds and doubling formulas for computer implementation.

Design of Robust Line-of-Sight Pointing Control System for the Scole Configuration

The design of a robust compensator is considered for the SCOLE configuration using a frequency-response shaping technique based on the LQG/LTR procedure. An additive perturbation formulation is used to obtain robustness to modeling errors. A satisfactory compensator is obtained by including the rigid modes and three elastic modes in the design model.

A discrete analog of the extended Bass algorithm for stabilizing constant linear systems

A discrete analog of the extended Bass algorithm for stabilizing continuous constant systems is discussed and computational experience from using both the continuous and discrete algorithms is presented.

On the linear optimal digital servo problem

Abstract For linear time-invariant digital systems, convergence of the Riccati equation associated with the optimal servo problem is examined. Necessary and sufficient conditions are established for the existence of finite gains when the command input trajectories may fail to be asymptotically stable.

An asymptotic property for a class of finite difference equations

Mathematical conditions are derived which characterize the asymptotic behaviour of a. class of finite difference equations. The results find application in the theory of optimal control.

ORACLS-A modern control theory design package

A digital computer program (ORACLS) for implementing the optimal regulator theory approach to the design of controllers for linear time-invariant systems is described. The user-oriented program employs the latest numerical techniques and is applicable to both the digital and continuous control problems.