Three-dimensional optimal skip entry with terminal maximum velocity

摘要

The optimal control and the optimal trajectory corresponding to this control at a skip 3D entry of a space vehicle into a planetary atmosphere is determined with reference to obtaining the maximum terminal velocity at a given azimuth. ^The optimal control to be determined involves the lift coefficient and the vehicle lateral inclination angle, that is, the roll angle. ^The problem is solved in the case of the entry general motion equations, that is, without making any approximation on these equations. ^One gives the initial conditions for the variables of state and the final conditions only for the altitude and azimuth. ^The final time is considered to be free. ^The final altitude should be equal to the initial altitude so that the entry should be a skip one. ^The optimization of this problem is solved applying the Pontriagin minimum principle. ^Thus, the above-defined problem of optimal control is transformed into a well-known two-point boundary problem. ^The problem was solved using a 'shooting'-type method. ^The calculations were performed for a skip' entry into the Earth atmosphere. ^(Author)