Accession Number : ADA309938

Title :   Multiple Model Adaptive Control of the Vista F-16.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Stepaniak, Michael J.

PDF Url : ADA309938

Report Date : DEC 1995

Pagination or Media Count : 177

Abstract : Multiple model adaptive control (MMAC) is investigated using the high-fidelity, nonlinear, six-degree-of-freedom Simulation Rapid-Prototyping Facility VISTA F-16. Detection of single actuator and sensor failures is considered, with an MMAC algorithm initially pursued which allows a controller specifically designed for each particular failure condition to replace the standard F-16 Block 40 flight control system (FCS) once the failure is detected. The synthesis of certain discrete-time LQG/PI controllers (those using control variables linearly dependent on state derivatives) is shown to be unattainable due to numerical difficulties. A novel control technique, termed control redistribution, is introduced which redistributes control commands (that would normally be sent to failed actuators) to the non-failed actuators, accomplishing the same control action on the aircraft. Multiple model adaptive estimation-based control redistribution is demonstrated to detect single failures in less than one second and to provide a response nearly identical to that anticipated from a fully functional aircraft in the same environment. Moreover, this method directly employs the proven Block 40 FCS, and no other, thereby guaranteeing desirable closed loop performance. A description of modifications necessary for in-flight testing is also provided. This research represents the most realistic simulation of multiple model adaptive control for flight control to date.

Descriptors :   *ADAPTIVE CONTROL SYSTEMS, *JET FIGHTERS, ALGORITHMS, SIMULATION, FLIGHT TESTING, DETECTION, DETECTORS, FLIGHT CONTROL SYSTEMS, DISTRIBUTION, SYNTHESIS, MODIFICATION, VARIABLES, ACTUATORS, FAILURE(MECHANICS), CLOSED LOOP SYSTEMS.

Subject Categories : Attack and Fighter Aircraft
      Flight Control and Instrumentation

Distribution Statement : APPROVED FOR PUBLIC RELEASE