Self-Designing Controller

Abstract:
If an aircraft in flight suffers a flight control, mechanical, electrical or hydraulic failure or damage due to midair collisions or adverse environmental conditions due to weather or battle. Barron's adaptive control law technology compensates for the failure in real time, thus preventing the loss of aircraft and of life.

Problem:
How does one design a control system that keeps an aircraft stable and flyable even in the presence of mechanical failures or damage? Moreover, how can such a control law be designed so that it does not need to be designed ahead of time to compensate for specific failures, but will tune itself in flight to adapt to unforeseen failures.



Solution:
BAI designed an indirect-adaptive control law that uses Modified Sequential Least Squares to build a mathematical model of the aircraft dynamics in flight. A Receding Horizon Optimal Controller then uses this information to generate control gains in real time that compensate for the failure. In a series of VISTA/F-16 flight tests, close tracking of flying-qualities models and continuous control law adaptation, including reconfiguration for single and multiple unforeseen effector impairments. Flight testing culminated with a smooth landing in crosswind conditions with a (simulated) missing left horizontal tail surface.

Links and References:

Air Force Research Laboratory website