Line-of-Sight Path Following Control on UAV with Sideslip Estimation and Compensation

This paper presents a new online reconfigurable line-of-sight (LOS) path following control approach for an unmanned aerial vehicle (UAV). First, a time-varying lookahead distance mechanism is developed for guaranteeing agile and abrupt actions of the UAV by moving it towards the desired path from which the UAV is far away, while generating more smooth operations of the UAV to reduce the fluctuations when it is close to the demanded path. Then, a self-adjustable integral LOS guidance strategy is devised to effectively compensate the steady-state errors and sideslip angles which are caused by the negative impacts from wind. The neural network technique is employed for learning and regulating control parameters of the proposed guidance law online in order to precisely counteract the adverse effects of time-varying wind-induced sideslips. Finally, extensive simulation studies are carried out to demonstrate the effectiveness of the proposed path following methodology.