DIFFERENCE EQUATIONS - ADAPTIVE CONTROLLER DESIGN TECHNIQUE.

Abstract

An 'identification' means for adaptive control systems is an average difference equation approximation for the vehicle transfer function. Solution of the difference equation, accomplished in the control computer of the adaptive system, determines which of several fixed compensators to use for existing flight conditions. The difference equation derived for the X-15 longitudinal dynamics is analyzed mathematically for various inputs. The X-15 pitch-rate loop and control computer is simulated on analog and digital computers. The difference equation solution error becomes large after two or three seconds. Exact difference equations for given flight conditions are generally more accurate. Significant errors still result after several seconds. Computer results indicated the difference equation solution was relatively accurate for not more than two or three seconds. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1966
Accession Number
AD0639693

Entities

People

  • Theodore T. Stein Jr.

Organizations

  • Air Force Institute of Technology

Tags

DTIC Thesaurus Topics

  • Adaptive Control Systems
  • Adaptive Systems
  • Computers
  • Control Systems
  • Difference Equations
  • Digital Computers
  • Equations
  • Transfer Functions

Readers

  • Control Systems Engineering.