Adaptive Systems with Closed–loop Reference Models: Composite control and observer feedback

A class of Closed-loop Reference Models (CRM) was shown in Gibson et al. (2013) to have improved transient performance. In this paper, we show that the introduction of CRM in Combined direct and indirect Model Reference Adaptive Control (CMRAC) leads to significant improvement in their transient response as well. We also show that CRM allow stable feedback of noise-free state estimates in CMRAC. Theoretical derivations are supported with numerical simulations.