The results are presented of application of the methodology of Singular Perturbations and Time Scales (SPATS) to the control of digital flight systems. A block diagonalization method is described to decouple a full order, two time (slow and fast) scale, discrete control system into reduced order slow and fast subsystems. Basic properties and numerical aspects of the method are discussed. A composite, closed-loop, suboptimal control system is constructed as the sum of the slow and fast optimal feedback controls. The application of this technique to an aircraft model shows close agreement between the exact solutions and the decoupled (or composite) solutions. The main advantage of the method is the considerable reduction in the overall computational requirements for the evaluation of optimal guidance and control laws. The significance of the results is that it can be used for real time, onboard simulation. A brief survey is also presented of digital flight systems. Naidu, Desineni S. and Price, Douglas B. Langley Research Center RTOP 506-46-21-01...

In this book, control theory merges with singular perturbation techniques to form the first comprehensive two-time-scale methodology for the modeling, analysis and design of control systems. Its goal is to simplify the software and hardware implementation of control algorithms, while improving their robustness properties. The text is intended for control engineers and graduate students who seek an introduction to singular perturbation methods in control. A feature of the book is the illustration of two-time-scale analysis and design procedures by way of case studies drawn from flight control, power systems and adaptive control.

This book presents the twin topics of singular perturbation methods and time scale analysis to problems in systems and control. The heart of the book is the singularly perturbed optimal control systems, which are notorious for demanding excessive computational costs. The book addresses both continuous control systems (described by differential equations) and discrete control systems (characterised by difference equations).