Resumen
Underwater vehicle-manipulator system (UVMS) can be applied to fulfill different complex underwater tasks such as grasping, drilling, sampling, etc. It is widely used in the field of oceanographic research, marine exploration, military, and commercial applications. In this paper, the dynamic simulation of UVMS is presented in the process of grasping an object. First, the dynamic model of UVMS, which considers the change of the load of manipulator when the end effector of manipulator grasps the object, is developed. To compare different conditions, numerical simulation of grasping processes without/with vehicle attitude control are carried out. The simulation results show that the coupling dynamics between the vehicle and the manipulator in the grasping process are clearly illustrated. It deteriorates the positioning accuracy of the end effector of the manipulator and is harmful to underwater precision operations. The tracking position error of end effector without vehicle control is large and UVMS cannot complete the grasping task under this condition. Vehicle control can compensate the motion of the vehicle due to the coupling effect caused by the motion of the manipulator. This study will contribute to underwater operation mission for UVMS with floating base.