Nonlinear adaptive control synthesis using U-model for multivariable underwater remotely operated vehicle

This paper presents the development of ROV control modelling and control synthesis using nonlinear adaptive U-model approach. Nonlinear ROV model based on the dynamic equation using the Newtonian method and derivation towards the kinematics equations and rigid-body mass matrixes are explained. This nonlinear ROV model represents the underwater thruster dynamics, ROV dynamics and kinematics related to the earth-fixed frame. MIMO Nonlinear adaptive control synthesis using U-model approach incorporate with neural networks algorithm are developed with MATLAB™ Simulink software and integrated together with the nonlinear ROV model using Internal Model Control structure. The controller output is based on Newton Raphson recursive algorithm with learning rate value between zero and one which improve the system stability. Radial basis function (RBF) is chosen for the neural networks activation function due to faster learning speed. Results show good control signal convergence and tracking performance between plant or system model with U-model polynomial.