SOME GENERALIZATIONS IN SYSTEM THEORY AND THEIR APPLICATIONS TO CONTROL SYSTEMS,

Abstract

Some definitions of the concepts 'state' and 'state-deterministic system' have been given by L. A. Zadeh and C. A. Desoer in their book 'Linear System Theory: The State Space Approach'. In this thesis, using some of their ideas such as physical systems and their measurable attributes, a more fundamental definition of a 'system' is given. Two new concepts, namely, 'functional dependence' and 'quasi-functional dependence' between attribute sets, are introduced, by means of which the concepts of output, input, and state, attribute sets are defined. Comparison of systems in two ways, in terms of their 'index sets' and in terms of their 'attributes sets,' is used to clarify the concepts of 'extensionally-state-determined' and 'extensionally-state-stochastic' systems. The concept of 'versatility of a system' is next introduced to provide a third way of comparing two systems. It is shown that if a linear control system is less versatile than another, it is as versatile as the latter system provided with a suitable linear feedback and with the system matrix same as that of the first. Two theorems are proved regarding the versatility of linear free systems. A new perturbation process, called 'brief perturbation process' here, which can be applied to control systems, is described in detail. Next, an interesting connection between uncontrollability and optimality is pointed out and the well-known sufficient conditions for controllability of a linear time-invariant control system are derived. Finally, a new definition of impulse response for linear as well as nonlinear control systems, using the concept of a brief perturbation process, is given. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1967
Accession Number
AD0653524

Entities

People

  • Sadanand D. Agashe

Organizations

  • University of Illinois Urbana–Champaign

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Closed Loop Systems
  • Control Systems
  • Feedback
  • Linear Systems
  • Perturbations

Fields of Study

  • Mathematics

Readers

  • Control Systems Engineering.
  • Mathematical Modeling and Probability Theory.
  • Theoretical Analysis.

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers