$mathcal {L}_1$ Adaptive Control for Safety-Critical Systems

This article presents the development of L₁ adaptive-control theory and its application to safety critical flight control system (FCS) development. Several architectures of the theory and benchmark examples are analyzed. The key feature of L₁ adaptive-control architectures is the decoupling of estimation and control, which enables the use of arbitrarily fast estimation rates without sacrificing robustness. Rohrs´s example and the two-cart system are used as benchmark problems for illustration. NASA´s flight tests on subscale commercial jet verify the theoretical claims in a set of safety-critical test flights.