VSTOL aircraft longitudinal control using fuzzy logic

Hybrid fuzzy-PID (HFPID) control, the cascade of a fuzzy and a conventional PID controller with the fuzzy controller acting as the designer of the PID controller, is applied to the control of the longitudinal axis of a VSTOL aircraft. The control of the longitudinal axis is a nonlinear problem complicated by the transition from hover to normal flight required by a VSTOL aircraft. This transition region may introduce singular matrices not usually encountered in a normal flight regime, hence requiring existing techniques to be compensated. A HFPID controller is designed and simulation results are presented