Citation: Xue, G.; Liu, Y.; Shi, Z.; Guo,
L.; Li, Z. Research on Trajectory
Tracking Control of Underwater
Vehicle Manipulator System Based on
Model-Free Adaptive Control
Method. J. Mar. Sci. Eng. 2022, 10,
652. https://doi.org/10.3390/
jmse10050652
Academic Editors:
Jacopo Aguzzi, Sascha Flögel
and Alessandro Ridolfi
Received: 24 March 2022
Accepted: 10 May 2022
Published: 11 May 2022
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Journal of
Marine Science
and Engineering
Article
Research on Trajectory Tracking Control of Underwater Vehicle
Manipulator System Based on Model-Free Adaptive
Control Method
Gang Xue
1,2
, Yanjun Liu
1,3,
* , Zhenjie Shi
3
, Lei Guo
1
and Zhitong Li
4,
*
1
Institute of Marine Science and Technology, Shandong University, Qingdao 266237, China;
xuegangzb@163.com (G.X.); rendar_lx@163.com (L.G.)
2
Key Laboratory of Ocean Observation Technology, Ministry of Natural Resources, Tianjin 300112, China
3
National Demonstration Center for Experimental Mechanical Engineering Education, Key Laboratory of
High-Efficiency and Clean Mechanical Manufacture of Ministry of Education, School of Mechanical
Engineering, Shandong University, Jinan 250061, China; shizhenjie1992@163.com
4
Qingdao Institute of Marine Geology, Qingdao 266237, China
* Correspondence: lyj111yjslw@163.com (Y.L.); lizhitong199488@163.com (Z.L.)
Abstract:
In order to improve the trajectory tracking accuracy of an Underwater Vehicle Manipulator
System (UVMS) under uncertain disturbance conditions of ocean current, a Model-free Adaptive
Control (MFAC) method was used. Combined with Radial Basis Function Neural Networks (RBFNN),
the RBFNN-MFAC method is proposed to improve the performance of the controller. A hydrody-
namic model of UVMS was defined in the commercial software, Fluent, to calculate hydrodynamics
disturbance, and the mechanism of the dynamic model of UVMS was defined in the commercial
software, Adams, to simulate the motion of UVMS. The trajectory tracking performance with various
control schemes, including PID (Proportional Integral Derivative), MFAC and RBFNN-MFAC, were
analyzed with the Adams and Simulink joint simulation model. The results show that the position
tracking accuracy and the speed tracking accuracy with the MFAC control scheme were 68.1% and
81.0% better, respectively, than those with PID control scheme. The position tracking accuracy and
the speed tracking accuracy with the RBFNN-MFAC control scheme were 66.3% and 43.1% better,
respectively, than those with the MFAC control scheme. The MFAC control scheme and the RBFNN-
MFAC control scheme proposed in this paper exhibit good trajectory tracking performance without
the precise dynamic model of UVMS, which is of great importance to applications in engineering.
Keywords:
underwater vehicle manipulator system; model-free adaptive control; disturbance
rejection control; trajectory tracking
1. Introduction
Underwater Vehicle Manipulator Systems (UVMSs) are important for ocean explo-
ration and have been widely used in offshore oil production [
1
], marine aquaculture [
2
],
underwater asset inspection [3] among other applications.
A UVMS is composed of two subsystems, the underwater vehicle and the underwater
manipulator [
4
]. The kinematics and coupling effect between the underwater vehicle and
manipulator are intrinsic factors affecting the performance of a UVMS. Wang et al. [
5
] pro-
posed a new redundancy resolution method to address the motion coordination problem
between the underwater vehicle and underwater manipulator of the UVMS that consists of
a fuzzy logic component and a multitasks weighted gradient projection method compo-
nent. Considering the effect of hydrodynamic force, Ambar et al. [
6
] proposed a resolved
acceleration control (RAC) method to control a dual-arm UVMS and achieved coordinated
control between the vehicle and the two robotic arms. Tang et al. [
7
] developed a control
framework consisting of online motion planning, multitask kinematic control, dynamic
feedforward compensation, and adaptive parameter undulatory control for a UVMS, in
J. Mar. Sci. Eng. 2022, 10, 652. https://doi.org/10.3390/jmse10050652 https://www.mdpi.com/journal/jmse
