Multivariable fast nonsingular terminal sliding mode control for remotely operated vehicle

Remotely Operated Vehicle (ROV) need to maintain the stability of the ROV body as much as possible to achieve efficient operation, so the ROV dynamic positioning technology is essential. A new multivariable fast nonsingular terminal sliding mode control (MFNTSM) method is proposed for the problem that global convergence of the nonsingular terminal sliding mode control (NTSM) method is slow. The six-degree-of-freedom motion model of our ROV is established based on the hydrodynamic coefficients calculated by the pool experiment and numerical simulation. Finally, the new sliding mode controller (MFNTSM) is simulated and compared with the NTSM under the condition of static water and disturbance. Simulation results show that the MFNTSM controller has better convergence speed and better robust performance than the NTSM controller in the dynamic positioning system.