Realization of fault tolerant control using μ-synthesis for the reusable launch vehicle

The reusable launch vehicles fly glidingly without any thrusts in the returning phase. In this phase, one of the most possible and important faults in the airframe is a jamming of the elevon. In order to make the control system tolerant to this failure, the flight control system is required to keep the stability and performance even if such failure occurs. Since this kind of faults can be modeled as a structured parameter deviation from robust control point of view, this paper presents some new ideas to realize the fault tolerant flight control system based on the μ-synthesis, and apply it to the reusable launch vehicle HOPE-X (H-II Orbiting Plane-Experimental) as an example. Also, some simulations are demonstrated to verify the usefulness of the proposed method.