Michael L. Workman

Adaptive Proximate Time-Optimal Servomechanisms: Continuous Time Case

A Proximate Time-Optimal Servo (PTOS) is developed, along with conditions for its stability. An algorithm is proposed for adapting the PTOS (APTOS) to improve performance in the face of uncertain plant parameters. Under ideal conditions APTOS is shown to be uniformly asymptotically stable. Simulation results demonstrate the predicted performance.

Adaptive proximate time-optimal servomechanisms: Discrete-time case

Following a brief review of the continuous time proximate time-optimal servomechanism (PTOS), a discrete time PTOS is developed, along with conditions for its stability. An algorithm is proposed for adapting PTOS when the plant parameters are not known yielding APTOS (adaptive PTOS). Under ideal conditions APTOS is shown to be uniformally asymptotically stable. Simulation results demonstrate the predicted performance, and experimental results validate the practicality of APTOS.

Adaptive Time-Optimal Control of Flexible Structures

The Extended Proximate Time-Optimal Servo (XPTOS) developed in [8] is analyzed for stability using new techniques. The XPTOS system operates in closed loop, and blends in its structure the characteristics of a time-optimal control law and the fine tracking properties of a properly tuned linear regulator. This study is addressed to the (idealized) case of flexible structures that contain a single or dominant structural mode. Simulation results demonstrate the performance of the XPTOS, and delineate its range of applicability.

Minimum-Time Control Of Large Space Structures

An Extended Proximate Time-Optimal Servomechanism (XPTOS) is developed for the control of a flexible structure with a single structural mode. The resulting control system is closed-loop , and embodies in its structure the characteristics of a time-optimal control law and the fine tracking properties of a properly tuned linear regulator. Simulation results demonstrate the performance of the XPTOS, and its robustness in the face of uncertain plant parameters.