Adaptive prescribed performance control for dynamic positioning SSPs with dynamic actuators’ faults

Abstract

This paper presents a control scheme for the dynamic positioning (DP) semi-submersible platform (SSP) with dynamic actuators’ faults. In this algorithm, robust damping technique is employed to adaptively compensate for actuator gain uncertainties and system model uncertainties. Furthermore, by incorporating a tuning parameter with contractibility into a $ln$-type performance function, a simplified prescribed performance control (PPC) strategy based on barrier error transformation is derived. The dynamic error is ensured to converge from the initial state to the predefined region by means of shifting function. Additionally, a fault correcting gain is used to provide online compensation for the effects of dynamic actuators’ faults, which is incorporated into the adaptive controller. Under the effect of the designed controller, all signals within the entire closed-loop system are proved to semi-globally ultimately uniformly bounded (SGUUB) stability by the Lyapunov stability theory. Finally, the closed-loop performance simulations confirm the algorithm’s effectiveness in PPC and FTC, the comparison simulations confirm the algorithm’s superiority with the faster convergence speed, economic efficiency, and reduced computational burden.