A reentry trajectory planning approach satisfying waypoint and no-fly zone constraints

A trajectory planning approach is proposed for the reentry vehicle with relatively high lift-to-drag ratio. Multiple constraints including waypoints and no-fly zones are taken into consideration. The three-dimensional trajectory planning problem is decomposed into a longitudinal trajectory planning subproblem and a lateral trajectory planning subproblem. The former is to determine a drag-energy profile (D-E profile) that is consistent with the required trajectory length and satisfies the given path constraints except waypoints and no-fly zones. The latter is to specify the sign of bank angle for satisfying the waypoint and no-fly zone constraints and minimizing the final crossrange error. The trajectory length and lateral maneuverability may not meet requirements, so an adjustment of D-E profile is required after solving the previous subproblems. Thus, the longitudinal trajectory planning and lateral trajectory planning subproblems are iteratively solved to converge to a feasible three-dimensional trajectory which meets all the path and terminal constraints. The trajectory planning approach is tested using the Common Aero Vehicle model. Simulations demonstrate that the approach consistently achieves the desired target conditions within allowable tolerances and satisfies waypoint and no-fly zone constraints.