Integrated fuzzy controllers for aircrafts under faulty flight conditions

摘要

In this paper an intelligent control design methodology is presented for the design of controller for commercial aircrafts operating under abnormal flight conditions. The intelligent methodology is fuzzy logic based, i.e. a group of fuzzy controllers are designed and used as an adaptive control system to meet transient specifications determined by a desired reference model. A linearized aircraft model utilized to simulate failures in the aircraft and test the effective intelligent fuzzy controller. A baseline controller is used for performance comparison of the fuzzy logic control in its ability to operate the aircraft under abnormal flight conditions. First an individual fuzzy controller was developed for each state of the aircraft and then the controllers are integrated together to test their performance as an integrated control system. The testing was conducted in three phases: 1) Nominal flight conditions, 2) a stall of the right aileron at 0.2 radians, and 3) a stall of the right aileron at max upward level. The integrated fuzzy controller was interfaced with the left aileron only to observe its effectiveness in compensating the failed aileron of the other side of the aircraft wing. The results from the integrated fuzzy controller produced the desired results and at a faster rate compared with the baseline controller both under nominal and failure—1 flight conditions. The test results under failure—2 flight conditions were acceptable in terms of compensation speed and correcting the failed state. However, the time needed to completely identify and maintain the state was a little less than desired. Overall the performance of the integrated fuzzy controller was superior to that produced by the baseline controller.