Probabilistic robust control of rotorcraft

This paper presents an approach for the design of reliable high-performance control systems for rotorcraft in order to enhance handling qualities and ensure closed-loop stability. The proposed control system has a two-tier hierarchical architecture. The lower-tier controller is designed using a probabilistic robust control approach. By allowing different levels of risk under different flight conditions, the control system can trade off between stability robustness and nominal performance. The upper-tier supervisory controller monitors the system response for anomalous behavior that might lead to instability or loss of performance. The supervisor may then switch between robust controllers with different levels of risk and performance.