Research On Vertical Trajectory Optimization Strategy Based On TBO

This thesis focuses on the optimization strategy of the vertical profile trajectory of an aircraft.According to the flight characteristics of each phase of the whole flight process,under the trajectory-based operation mode,three phases of cruise,climb and descent are analyzed individually before the joint optimization of the trajectory of the whole process.Firstly,in the cruise phase,an altitude layer assignment and conflict resolution model is constructed,an altitude layer assignment strategy is formulated,and the total fuel consumption of multiple flights is minimised as the optimisation objective.In the climb and descent phases,a dynamics model is constructed and a multi-stage control formula is established based on the optimal control theory,and a Gaussian pseudo-spectral method is used to solve the multi-stage optimal control problem to obtain the optimal continuous climb operation trajectory and continuous descent operation trajectory,which are compared with the traditional stepped operation mode.Finally,according to the operation characteristics of each stage,the trajectory search optimization is carried out for the whole process of single aircraft flight under the limited general state,initial state and terminal state of each stage,and the sensitivity analysis is carried out for the continuous climb apex and continuous descent apex.In order to better match the cruise phase on the articulation,the aircraft enters the airspace cruise start point or the specified position for the timed and fixed control,and the simulation results obtained are helpful to understand the the characteristics of an optimal trajectory with flight time and fuel consumption as the optimisation metrics.In addition,the trajectory information given can provide flight guidance on the vertical profile trajectory for the whole flight process from climb to cruise to descent.