LAUSR

Actuator aging is generally unavoidable in practice, and it may lead to the degradation of system performance. Therefore, how to resist the uncertainties caused by aging during the system operation is important in modern control systems. In this paper, the authors aim to address such a problem by considering controlling strict feedback systems with unknown actuator aging. Unlike the traditional parameter estimation, a piecewise update law with non-linearized aging parameters is constructed by using mean value theorem and maximum–minimum property. Thus, a new adaptive control scheme is developed successfully. It is shown that the effects caused by aging can be compensated by the proposed control law, and system stability, tracking, and transient performance can also be guaranteed.