Autonomous Free-Floating Underwater Assembly Control for an Underwater Biomimetic Vehicle-Manipulator System

In this article, an improved coordinated control method based on the tracking differentiator with a median filter and dynamic surface control was proposed for an autonomous free-floating underwater assembly manipulation. In addition, the disturbances caused by the manipulator’s motion were considered and compensated by a feedforward controller of the manipulator. Furthermore, the inward counter-propagating sinusoidal waves of the biomimetic undulatory-finned propulsors were adopted and a fuzzy logic controller was designed to realize the transformation between the control parameters and the demanded propulsive forces. The stability of the proposed control scheme was proven by the Lyapunov theory. Finally, practical experiments verified that the control scheme can complete the autonomous free-floating underwater assembly manipulation task, which indicated the good feasibility and robustness of the proposed methods.