Rapid re-entry trajectory optimization for boost-glide missile

Rapid re-entry trajectory optimization of near space boost-glide missile was studied via the Legendre-Gauss-Lobatto(LGL) pseudospectral method.Firstly,an accurate mathematics model in re-entry phase was established based on an improved aerodynamic model.Aiming at the difficulties of the optimization problem in processing of aerodynamic data as well as optimization solving,the steps based on LGL pseudospectral method were listed systemically for solving the optimal re-entry flight trajectory.Then a serial strategy based on LGL pseudospectral method was presented to deal with the difficulties in optimization using the LGL pseudospectral method directly.Finally,the feasibility and the optimality of optimal result were validated by integral propagation method and covector mapping principle,respectively.Simulation results show that computational time required for optimizing one re-entry trajectory is 3~4 s,and thus the computational efficiency is high.Path constrains and boundary constrains are well satisfied,and the precision of this trajectory optimization method is high.The rapid re-entry trajectory optimization with characteristics of multiple constraints,multiple variables and large sparsity is achieved.