Backstepping and integrative sliding mode control for trajectory tracking of a hybrid remotely operated vehicle

Many Hybrid Remotely Operated Vehicles (HROVs) have been designed according the biomicry principles for performance improvements. To obtain an appropriated navigation control of a HROV it is necessary to know its accurate mathematical model. In order to avoid troubles in the design of control due to the lack of precision in HROV model parameters, in this paper it is proposed an integrative sliding mode control combined with a backstepping control. This approach control has the main property of overcoming the imprecision of model parameters. To design the sliding mode control is necessary to calculate the switching surface, which is determined utilizing two similar transformations of the linearized model. This discontinuous control has two parts: First, the control which drives any trajectory to switching surface and second, the control when states of model are on the switching surface, called equivalent control; in this case, this control was replaced by the backstepping controller. The system was simulated with input disturbances. This control proved to be robust in the presence of limited system nonlinearities, as well as limited disturbances.