Trajectory Generation On Approach & Landing For A RLV Using NOC Approach
A major objective of next generation reusable launch vehicle (RLV) programs includes significant improvements
in vehicle safety, reliability, and operational costs. In this paper, trajectory generation on approach/landing (A&L) for RLVs
using motion primitives (MPs) and neighboring optimal control (NOC) is discussed. The proposed trajectory generation
approach at A&L phase is based on an MP scheme which consists of trims and maneuvers. From an initial point to a given
touchdown point, all feasible trajectories that satisfy certain constraints are generated and saved into a trajectory database.
An optimal trajectory can then be found off-line by using Dijkstra’s algorithm. After perturbations are imposed on the initial
states of the off-line optimal trajectory, it is reshaped into a neighboring feasible trajectory on-line by using NOC approach.
At this point, a neighboring feasible trajectory existence theorem (NFTET) is investigated and its proof is provided as well.
The results show that the vehicle with stuck effectors can be recovered from failures in real time. Finally, robustness issues
on NOC approach are briefly discussed.