Modelling, simulation and optimal control for an aircraft of aileron-less folding wing

The purpose of this paper is to discuss the method of modeling and control system design for a loitering aircraft of aileron-less folding wing. A nonlinear model of the aircraft was established, and then linearized by small disturbance method. The lateral-directional stability augmentation options were analyzed through the root locus plots. The pole placement method based on linear quadratic regulator (LQR) technology was used to achieve desirable dynamic characteristics. In the analysis, the state parameters which represent rapid oscillation states of the aircraft such as roll rate and yaw rate were set as primary control parameters in the inner loop. The states oscillated slowly such as rolling angle and yaw angle were set as main control parameters in the outer loop. Based on the self-organizing fuzzy control algorithm, the aircraft can be controlled to fly in a desired path. Two types of course control plan were investigated and verified. The results show that the control plans are feasible and the control system is adequately robust to meet the requirements of the course control.