Small UAV controlled by an online adaptive fuzzy control system

Abstract

Since small unmanned helicopter flight attitude control process has strong time-varying characteristics and random disturbances, the conventional control methods with unchanged parameters are often unworkable. An online adaptive fuzzy control system (AFCS) is designed in this paper, in a way that a process model of the plant or its approximation in the form of a Jacobian matrix is not required. An online AFCS implements a simultaneous online tuning of fuzzy rules and the output scale factors of the system. A two-cascade controller is designed with an inner (attitude controller) and outer controller (navigation controller) of the small unmanned helicopter. At last, an attitude controller based on an online AFCS is implemented. The flight experiments show that the proposed fuzzy logic controller provides quick response, small overshoot, high accuracy, robustness and adaptive ability. It satisfies the needs of autonomous flight.