A Tracking Controller Design For A Class Of Underactuated Systems

Underactuated systems have recently received considerable attention from the control community.As a kind of typical underactuated system,tracking control of underactuated surface ships are important for research significance and practical value.This paper mainly focus is the tracking control problem of underactuated surface vessels,which has uncertainties parameters and environmental disturbance.The main results of this paper are as follows:1.We introduce a 3 degree-of-freedom kinematics model and dynamics model of underactuated surface vessels,which has uncertainties parameters and environmental disturbance.2.The simultaneous stabilization and path following control problem is considered for underactuated surface vessels with uncertain parameters.We design an integrative controller by using Lyapunov's direct method,backstepping technique and robust adaptive projection algorithm.Through the stability analysis,we prove under certain conditions,the designed controller can achieve simultaneous stabilization and path following control.And the numerical simulations verify the validity and robustness of the adaptive stabilization and path following integrated control algorithm.3.For a 3 degree-of-freedom underactuated surface vessels system with external dynamic disturbance.We use Serret-Frenet coordinate and nonlinear state transformation to transform the system into a SISO nonlinear chain system.By using the disturbance observer to compensate the influence of external dynamic disturbance,we propose a composite generalized predictive anti-disturbance controller,which integrate the nonlinear disturbance observer with the feedback loop.The controller guarantees that the system state trajectories can asymptotically track the given reference trajectories.The numerical simulations demonstrate the validity of the antidisturbance control strategy.