Combined adaptive control with unmodelled dynamics

This paper considers the combined method of adaptive control in the presence of unmodelled dynamics. For the direct method, it is well known that modifications in the adaptive laws are needed to cope with unmodelled dynamics and retain stability robustness. For the combined adaptive control, this paper addresses to a simulation study of three modifications in the adaptive laws. This study indicates that a recently developed modification yields an improved performance, as compared with the earlier modifications.