Control of an underactuated underwater vehicle manipulator system in the presence of parametric uncertainty and disturbance

Abstract

In this paper, an underactuated underwater vehicle manipulator system (u-UVMS) carrying 6-DOF manipulator system is modeled considering hydrostatic forces and hydrodynamic effects such as added mass, lift, drag and side forces. The shadowing effects of the bodies on each other are also taken into account when computing the hydrodynamic forces. The system equations of motion are then derived using Newton-Euler formulation including the thruster dynamics.Next, an inverse dynamics control algorithm is applied for the end-efrector trajectory tracking of the u-UVMS. Simulation results illustrate that the control method is applicable to underactuated systems and is efrective even in the presence of parametric uncertainty and disturbing current force.

Trajectory Tracking Control of an Underactuated Underwater Vehicle Redundant Manipulator System

“…. The 6‐DOF manipulator of U‐UVMS‐6 and 8‐DOF redundant manipulator of U‐UVMS‐8 have the same mass and fully extended lengths. The extra revolute joints in the redundant manipulator of U‐UVMS‐8 are placed between links 2 and 3 and between links 4 and 5 to further compensate undesired motions of the AUV.…”

“…. Weighted mean squared error (W‐MSE) values of the positional tracking errors obtained for the end‐effector of U‐UVMS‐8 are less than those of U‐UVMS‐6 during the execution of the same predefined tasks of the AUV and the manipulator given in even with smaller controller gains as shown in Table . W‐MSE values are obtained in such a way that the initial transient‐phase errors are less heavily weighted by means of an appropriate weighting function.…”

“…The control method allows utilization of the manipulator motion to perform secondary tasks like drag minimization, obstacle avoidance or avoidance of joint limits. Korkmaz et al applied an inverse dynamics control algorithm to an underactuated underwater vehicle having a 6‐DOF manipulator considering parametric uncertainty and ocean disturbance. Mohan and Kim presented an indirect adaptive control method for a UVMS based on an extended Kalman filter.…”

“…The purpose of this study is to control the position of a spatial underactuated underwater vehicle manipulator system (U‐UVMS). To this end, a U‐UVMS with an 8‐DOF redundant manipulator (U‐UVMS‐8) is used in order to increase the positioning accuracy of the end‐effector with regard to that of the U‐UVMS having a regular 6‐DOF manipulator (U‐UVMS‐6) described in . The AUV, which has three planes of symmetry with a prolate spheroidal shape, has four thrusters.…”

Reduction of the dynamic coupling in an underwater vehicle-manipulator system using an inverse dynamic model approach

“…The authors proposed an analysis technique that relates the inverse dynamic model with a second order filter. Korkmaz et al (2013) present a control method for the UVMS based on inverse dynamics. The interaction forces between the vehicle and manipulator are computed and used in the control law that aims to linearise the system.…”