Hitoshi Katayama

Straight-Line Trajectory Tracking Control for Sampled-Data Underactuated Ships

Straight-line trajectory tracking control of sampled-data underactuated ships with both state and output feedback controllers is considered and analyzed by resorting to a nonlinear sampled-data control theory. State feedback controllers and reduced-order observers are designed on the basis of the Euler approximate models. Then they are combined to obtain output feedback controllers that semiglobally practically uniformly asymptotically stabilize the tracking error dynamics. Both simulation and experimental results are given to show the efficiency of the designed controllers.

Design of output feedback consensus controllers for nonlinear sampled-data multi-agent systems of strict-feedback form

Design of reduced-order observer-based output feedback consensus controllers for nonlinear sampled-data multi-agent systems of strict-feedback form is considered based on nonlinear sampled-data control and consensus control theories. As a practical application of the proposed design method, output feedback consensus control for sampled-data fully actuated ships is also discussed.

Reduced-order observers for nonlinear sampled-data systems with application to marine systems

We design semiglobal and practical discrete-time reduced-order observers for the exact discrete-time model of nonlinear sampled-data strict-feedback systems. As an application of the proposed design method, we design reduced-order observers for sampled-data ships and show their efficiency by experimental and simulation results.

Design of output feedback stabilizing controllers for nonlinear sampled-data strict-feedback systems

Design of output feedback SPUA stabilizing controllers is considered for nonlinear sampled-data strict-feedback systems. It is also shown that the designed output feedback controllers SP-IS stabilize nonlinear sampled-data strict-feedback system with sampled observation noise. A numerical example is given to illustrate the proposed design of output feedback controllers.

Design of a state and disturbance observer for nonlinear sampled-data strict-feedback systems with constant disturbance

We consider the design of a state and disturbance observer that is semiglobal and practical in sampling period for the exact model of nonlinear sampled-data strict-feedback systems with unknown constant disturbance. As an application of the proposed design method, we design a state and disturbance observer for sampled-data underactuated ships that are influenced by unknown constant ocean currents. We show its efficiency by simulation results.

Reduced-order observers for nonlinear sampled-data strict-feedback systems with control input update delay

Design of reduced-order observers is considered for nonlinear sampled-data strict-feedback systems with control input update delay. On the basis of the Euler-like approximate model, reduced-order observers are designed. Then the relationship between the magnitude of control input update delay and that of estimation errors is discussed. A numerical example is also given to illustrate the theory.

Stabilization of nonlinear sampled-data systems with input update delay

Stabilization of nonlinear sampled-data systems with input update delay is considered. First the existence of state feedback semiglobally practically uniformly asymptotic stabilizing controllers is assumed for nonlinear sampled-data systems without input update delay. Then input update delay is introduced and the relationship between the magnitude of input update delay and degeneration of controllers is discussed. A numerical example is also given to illustrate the theory.

Observers and output feedback consensus controllers for continuous-time strict-feedback multi-agent systems with sampled observation

Design of observers and observer-based output feedback consensus controllers for continuous-time strict-feedback multi-agent systems with sampled observation is considered. First continuous-time observers for continuous-time multi-agent systems and discrete-time observers for their exact (discrete-time) models are designed. Then output feedback consensus controllers are constructed by combining the designed observers and state feedback consensus controllers. A numerical example is given to illustrate the proposed design method.