Design of Fault-Tolerant Landing Guidance for Multi-Engine Reusable Launchers

Kurzfassung

This work investigates whether, and in what manner, online guidance can provide fault tolerance in the presence of propulsion faults during the landing burn, and to determine the extent to which this contingency guidance remains effective throughout the descent. To this end, the effect of guidance re- configuration is analyzed in the presence of engine loss, thrust inefficiencies, and thrust vectoring faults. A return-to-launch-site scenario is considered, restricted to the landing phase, where the mitigation of engine faults is paramount to recover the vehicle. In such cases, a new optimal trajectory must be re- computed, constraining the solution to the new degraded vehicle resources. To address these challenges, a fault-tolerant landing guidance method for a multi-engine Reusable Launch Vehicle is developed, formulated through a sequential convex programming framework, where the optimization problem is updated according to the fault information. Monte Carlo simulations demonstrate that the algorithm is highly effective in generating feasible recovery trajectories under a wide range of fault scenarios. The results show that the proposed method allows successful recovery where nominal guidance would otherwise fail.