Kinematic and Dynamic Control of Cooperating Underwater Vehicle-Manipulator Systems

Abstract

Cooperative control of autonomous underwater robots can provide capabilities that exceed those of any single marine robot. In this paper, the cooperation between two different underwater vehicle-manipulator systems is considered. Cooperation is enabled through a control scheme which generates state-dependent reference signals to achieve synchronization of the end-effector positions of the robots. These references are tracked by the individual control systems, which consist of decoupled kinematic and dynamic controllers. Consequently, the control systems do not constrain the choice of cooperation scheme. Due to the kinematic redundancy of the robots, a task-priority inverse kinematics controller is used for velocity-level redundancy resolution, and several tasks are defined for each robot. Furthermore, the dynamics of the robots are controlled by a higher-order sliding mode controller, namely the generalized super-twisting algorithm with adaptive gains. The dynamic control approach provides robustness to model uncertainties and unknown disturbances. The effectiveness of the methods is verified in a simulation study on a heterogeneous pair of UVMSs.