Robust adaptive control of robotic manipulator with input time-varying delay

This paper presents H∞ adaptive tracking control of uncertain robotic manipulator with unknown external disturbances and input time-varying delays. The new adaptive scheme is proposed for trajectory tracking, while H∞ performance is used to attenuate the effect of external disturbances. Firstly, a delay-dependent sufficient condition with input delay and the proposed adaptive controller are developed for the uncertain robotic manipulator, such that the resulting closed-loop system is robustly asymptotically stable. Secondly, a sufficient condition for the H∞ disturbance attenuation performance of the closed-loop system is derived, consequently, the system is robustly asymptotically stable. In the end, two examples are presented to verify the effectiveness of the proposed method.