%J IEEE Access %L scholars13995 %A N.A.A. Hussain %A S.S.A. Ali %A M. Ovinis %A M.R. Arshad %A U.M. Al-Saggaf %P 1851-1865 %I Institute of Electrical and Electronics Engineers Inc. %X This paper presents the control modelling and synthesis using a coupled multivariable under-actuated nonlinear adaptive U-model approach for an unmanned marine robotic platform. A nonlinear marine robotics model based on the dynamic equation using the Newtonian method and derivation with respect to the kinematics equations and rigid-body mass matrixes are explained. This nonlinear marine robotics model represents the underwater thruster dynamics, marine robotics dynamics and kinematics related to the earth-fixed frame. Coupled multivariable nonlinear adaptive control synthesis using a U-model approach for the Remotely Operated Vehicle (ROV) and Unmanned Surface Vessel (USV) represent an unmanned marine robotics application. A comparison is presented for the proposed nonlinear control approach between the U-model control approach with nonlinear Fuzzy Logic Control and Sliding Mode Control for the ROV and USV platforms. The results show minimum mean square error values and tracking performance between the plant or system model with the proposed method. Lastly, robustness and stability analysis for the proposed U-Model nonlinear control approach are presented by implementing an adaptive learning rate value. © 2013 IEEE. %K Adaptive control systems; Fuzzy logic; Kinematics; Mean square error; Remotely operated vehicles; Robotics; Sliding mode control; Unmanned surface vehicles, Adaptive Control; Marine robotics; Minimum mean square errors; Non-linear adaptive controls; nonlinear; Remotely Operated Vehicles (ROV); Underactuated; Unmanned surface vessels, Nonlinear equations %V 8 %T Underactuated Coupled Nonlinear Adaptive Control Synthesis Using U-Model for Multivariable Unmanned Marine Robotics %O cited By 16 %D 2020 %R 10.1109/ACCESS.2019.2961700