Fault tolerant flight controller design using μ-synthesis for the unmanned winged re-entry space vehicles

Unmanned winged re-entry space vehicles glide without any thrust in their re-entry phase. In this phase, one of the most possible and important faults in the airframe is jamming of the elevon. In order to make control systems tolerant to this failure, the flight control system is required to keep its stability and the performance, even if such a failure occurs. Since this kind of fault can be modeled as a structured parameter deviation from a robust control point of view, this paper presents some new ideas to realize a fault tolerant flight control system based on μ-synthesis, and apply it to the unmanned winged re-entry space vehicle HOPE-X (H-II Orbiting Plane-Experimental). Simulations are also demonstrated to verify the usefulness of the proposed method.