Research On Ship Landing Control Technology Of Vertical Take-off And Landing Fixed-Wing UAV

The vertical take-off and landing fixed-wing UAV,with its convenient take-off and landing mode and high reliability,has become a popular model in small and medium-sized UAVs in recent years.According to the outstanding characteristics of vertical take-off and landing,its use for autonomous landing will greatly reduce landing difficulty and flight accidents and improve landing accuracy.At the same time,this kind of unmanned aerial vehicle also meets long-haul and heavy-duty offshore operations demand.In this paper,a complete set of control scheme is proposed for landing on the ship automatically and dynamically by using the special take-off and landing method for this kind of aircraft.While improving the precision of landing point,it will not cause damage to the UAV,The main research contents are as follows:Firstly,the complete six-degree-of-freedom mathematical model of the fixed-wing UAV is optimized and established,and the model-based object characteristics analysis is carried out to provide the basis for the control law design.Secondly,in order to enhance the wind resistance,the longitudinal control law of the fixed-wing UAV based on the total energy is designed to realize the decoupling of the speed and the track.The lateral control law based on the L1 guidance designed to improve the trajectory control accuracy.In addition,the anti-wind control law in the rotor mode is designed which will effectively reduce the moving time of the rotor landing.Next,based on the Gauss pseudo-spectral method,according to the initial and terminal states of the UAV in the transition phase of landing mode,the optimal trajectory is planned by selecting reasonable performance indexes.And several control strategies of composite mode are proposed.Through comparative analysis,the appropriate longitudinal and lateral control modes are determined.By using the optimal control tracking method,a good tracking of the nominal trajectory is achieved in the MATLAB environment,which verifies the rationality of the trajectory planning and the correctness of the control strategy.Finally,the whole automatical landing process is designed in functional segments,including guidance and capture segment,course calibration segment,flight straight segment,trajectory tracking segment and tracking dynamically segment.Based on ?C/OS-? kernel,we establish digital integrated simulation system,including flight control system,ground control system and simulation model system.We have realized the real-time digital simulation of the automatically landing on the moving ship for the vertical take-off and landing fixed-wing UAV.And the simulation data shows that the control scheme is reasonable and feasible.It has certain practical significance.