Granted Patent B2

US 12,466,526 · App. 18/365,909 · Granted Nov 11, 2025

Inventors: Tomoyasu Takahashi (Amagasaki, JP); Naoya Hashimoto (Nishinomiya, JP)

Assignee: FURUNO ELECTRIC COMPANY LIMITED

B63B79/40B63H25/04G05D1/0206

Abstract

Claims (55)

1 . A ship control device, comprising:

processing circuitry configured to:

set ship characteristic parameters of a combined system of first-order lag and dead time, which integrates a behavior of a rudder and a behavior of a ship;

calculate control parameters for feedback control with respect to a rudder angle of the rudder using the ship characteristic parameters;

perform the feedback control using the control parameters;

calculate a desired turnrate of a command rudder angle with respect to the rudder angle using the ship characteristic parameters;

perform the feedback control using the desired turnrate;

calculate the control parameters using an evaluation function including the rudder angle, a turnrate, and a heading as evaluation criteria; and

calculate the control parameters by including a squared error between an amount of overshoot of the heading with respect to the target heading and the target heading in the evaluation criteria.

2 . The ship control device of claim 1 , wherein the processing circuitry is further configured to:

calculate the desired turnrate using the ship characteristic parameters and a target heading.

3 . The ship control device of claim 1 , wherein the processing circuitry is further configured to:

calculate the control parameters by including a squared error between the desired turnrate and the turnrate in the evaluation criteria.

4 . The ship control device of claim 1 , wherein the processing circuitry is further configured to:

calculate the control parameters by including a squared value of the rudder angle in the evaluation criteria.

5 . The ship control device of claim 1 , wherein the processing circuitry is further configured to:

calculate steering quality indices using the heading, the turnrate and the rudder angle;

calculate a rudder speed using the rudder rate; and

calculate the ship characteristic parameters using the steering quality indices and the rudder rate.

6 . The ship control device of claim 5 , wherein the processing circuitry is further configured to:

calculate the ship characteristic parameters using a time-varying characteristic of the turnrate calculated from the rudder rate and the steering quality indices.

7 . The ship control device of claim 6 , wherein the processing circuitry is further configured to:

calculate the ship characteristic parameters using timings having different predetermined values for the turnrate in the time-varying characteristic.

8 . The ship control device of claim 7 , wherein the processing circuitry is further configured to:

calculate dead time or a time constant of steering quality in the ship characteristic parameters using the time-varying characteristic.

9 . The ship control device of claim 1 , wherein the processing circuitry is further configured to:

calculate steering quality indices using a length of ship between perpendiculars relative to the ship, a ship breadth of the ship, and a ship speed of the ship;

calculate a rudder speed using the rudder rate; and

calculate the ship characteristic parameters using the steering quality indices and the rudder rate.

10 . The ship control device of claim 9 , wherein the processing circuitry is further configured to:

calculate a turning ability index in the steering quality indices using the length of ship between perpendiculars and the ship breadth, and

calculate a time constant of steering quality in the steering quality indices using the turning ability index, the length of ship between perpendiculars, and the ship speed.

11 . The ship control device of claim 10 , wherein the processing circuitry is further configured to:

non-dimensionalize the turning ability index;

calculate a non-dimensionalizing time constant of steering quality from the non-dimensionalized turning ability index; and

dimensionalize the non-dimensionalizing time constant of steering quality.

12 . The ship control device of claim 2 , wherein the processing circuitry is further configured to:

calculate steering quality indices using the heading, the turnrate and the rudder angle;

calculate a rudder speed using the rudder rate; and

calculate the ship characteristic parameters using the steering quality indices and the rudder rate.

13 . The ship control device of claim 2 , wherein the processing circuitry is further configured to:

calculate steering quality indices using a length of ship between perpendiculars relative to the ship, a ship breadth of the ship, and a ship speed of the ship;

calculate a rudder speed using the rudder rate; and

calculate the ship characteristic parameters using the steering quality indices and the rudder rate.

14 . The ship control device of claim 13 , wherein the processing circuitry is further configured to:

calculate a turning ability index in the steering quality indices using the length of ship between perpendiculars and the ship breadth, and

calculate a time constant of steering quality in the steering quality indices using the turning ability index, the length of ship between perpendiculars, and the ship speed.

15 . A ship control method, comprising:

setting ship characteristic parameters of a combined system of first-order lag and dead time, which integrates a behavior of a rudder and a behavior of a ship;

calculating control parameters for feedback control with respect to a rudder angle of the rudder using the ship characteristic parameters;

performing the feedback control using the control parameters;

calculating a desired turnrate of a command rudder angle with respect to the rudder angle using the ship characteristic parameters;

performing the feedback control using the desired turnrate;

calculating the control parameters using an evaluation function including the rudder angle, a turnrate, and a heading as evaluation criteria; and

calculating the control parameters by including a squared error between an amount of overshoot of the heading with respect to the target heading and the target heading in the evaluation criteria.

Assignments (1)

Priority Claims (1)

Continuity (2)

References Cited (17)