Fault Tolerant Digital Flight Control with Analytical Redundancy

Item

Title
Fault Tolerant Digital Flight Control with Analytical Redundancy
Date
1977
Identifier
ADA045671
ADA045671
Abstract
Analytical redundancy offers high potential for solving the sensor redundancy problem. The current state-of-the-art in analytical redundancy contains a number of candidate filters which are developed here from a fundamental relationship of variables through hybrid simulation. Three analytical redundancy concepts of varying complexity were developed for the A-7D aircraft. Two monitor techniques were used: a multiple trip level exceedance criteria currently in use with voting systems, and a sequential likelihood ratio hypothesis test (SLRT) on the mean value of the error signal. Results indicate that fault detection, whether designed by classical methods or Kalman filtering, perform similarly and that gust estimation improves fault detection performance. Also, failure isolation for a single set of unlike sensors is difficult to achieve with a reasonable computation load. The output recommendation is to proceed to flight test with a set of nonlinear diagnostic filters to be used with comparison monitors for dual sensor failure isolation, creating a fail-operative dual sensor system. Fail-safe operation will also be achieved by continuing to monitor the filters and to detect, but not isolate, a second failure.
Date Issued
1977-05
Extent
396
Corporate Author
Honeywell Systems & Research Center
Laboratory
Air Force Flight Dynamics Laboratory
Report Number
AFFDL-TR-77-25
Contract
F33615-76-C-3031
DoD Project
1987
DoD Task
198701
Distribution Conflict
No
Access Rights
Approved for public release; distribution unlimited
Photo Quality
Incomplete
Distribution Classification
1
DTIC Record Exists
Yes
Report Availability
Full text available by request
Creator
Cunningham, Tom
Carlson, Don
Hendrick, Russ
Shaner, Don
Hartmann, Gary
Stein, Gunter
Provenance
University of Colorado Colorado Springs, Kraemer Family Library
Type
report