A dynamic weak-disturbance-decoupling-based prescribed performance control strategy for actual manipulators

In this article, an adaptive weak-disturbance-decoupling-based finite-time dynamic prescribed performance controller is firstly proposed for manipulators driven by servo motors with input nonlinearities. Combining weak disturbance decoupling and adaptive control, the uncertainties of manipulators are handled effectively, ensuring that the manipulators can operate over the entire time domain. Further, the disturbance effects on the manipulators are limited to a given form, and the asymptotic stability of tracking errors is achieved. Simultaneously, a dynamic performance function is introduced, which can be adjusted in real time, not only to constrain the behaviours of manipulators but also to guarantee their robustness against external disturbances. Because the sufficient differentiability of the performance function is ensured by the adjustment rules, the control voltages of the manipulators are continuous. For practicality, the saturation and dead-zone of control are considered. Finally, the effectiveness, superiority, and practical applicability are validated through the stability analysis, simulations, and real-world application.