Terminal Area Energy Management Trajectory Design And Guidance Research For Reusable Launch Vehicle

At present,many countries in the world are trying to carry out research on reusable launch vehicle(RLV).From Britain and the United States to Japan and India,many kinds of RLV have been developed and applied in varying degrees because of their ability to share costs through multiple use,short launch cycle and being used as return carriers.When reusable vehicles return to the airport,they usually fly back to the airport for recovery by powerless gliding.During the whole return flight,the flight environment changes enormously.The aircraft needs to go through many stages,such as derailment,reentry,energy management and landing,from the on-orbit operation state.There are problems to be solved in each stage.Terminal Area Energy Management is an important stage in flight,which is responsible for adjusting the large-scale uncertain flight state of the aircraft from the end of the reentry phase to the end of the runway alignment,so that the aircraft has the required flight state.In this paper,the flight of RLV in the Terminal Area Energy Management is discussed.By decoupling its three-dimensional trajectory,it is decomposed into longitudinal and transverse sections.On the basis of the analysis of flight safety requirements,the energy corridor boundary is given in the longitudinal section.According to the energy corridor,combined with the actual flight situation and the design requirements for engineering application,the longitudinal nominal trajectory is given.The requirement of guidance law design for longitudinal and lateral synthesis of aircraft is analyzed,and the problems that need to be solved for each direction guidance law are clarified.Aiming at these problems,the guidance scheme and guidance law of aircraft in Terminal Area Energy Management phase are given.In the longitudinal direction,the combination of altitude tracking and multi constraint control is used for guidance,and the guidance law is given;in the lateral direction,the strategy of subsection control is used to make the RLV realize the energy management while tracking the altitude,and meet the conditions for entering the next stage at the end.The correctness of the guidance system is verified by simulation analysis in nominal state.The anti-jamming ability of the guidance system is verified by applying certain uncertainty to the initial state using Monte Carlo simulation method.