Automatic steering device, automatic steering system, automatic steering method, and automatic steering program
To control an automatic steering appropriately regardless of a ship speed, an automatic steering device includes processing circuitry. The processing circuitry acquires motion information including a ship length and a ship speed. The processing circuitry identifies a non-dimensionalizing motion parameter based on the ship length and the motion information. The processing circuitry generates a dimensionalizing motion parameter by dimensionalizing the non-dimensionalizing motion parameter based on the ship speed. The processing circuitry sets a control parameter of the model-based controller based on the dimensionalizing motion parameter.
1. An automatic steering system comprising:
an automatic steering device comprising:
processing circuitry configured to:
acquire a ship length and motion information including a ship speed;
identify a non-dimensionalizing motion parameter based on the ship length and the motion information;
generate a dimensionalizing motion parameter by dimensionalizing the non-dimensionalizing motion parameter based on the ship speed; and
set a control parameter of a model-based controller based on the dimensionalizing motion parameter; and
a rudder configured to control a rudder angle based on a command rudder angle generated by the automatic steering device.
2. The automatic steering system according to claim 1 , wherein the processing circuitry is further configured to:
generate the dimensionalizing motion parameter based on the ship speed when the ship speed changes by more than a preset threshold value after generating the dimensionalizing motion parameter; and
update the control parameter based on the dimensionalizing motion parameter after the change in the ship speed.
3. The automatic steering system of claim 2 , wherein the processing circuitry is further configured to:
generate the dimensionalizing motion parameter when a predetermined time elapses from a time when the dimensionalizing motion parameter is generated; and
update the control parameter based on the dimensionalizing motion parameter after the predetermined time elapses.
4. The automatic steering system according to claim 3 , wherein the processing circuitry is further configured to:
acquire a target direction of the ship and a heading of the ship,
switch the control mode of automatic navigation based on a deviation between the target direction and the heading, and
identify the non-dimensionalizing motion parameter based on the motion information of the ship acquired in the control mode before the switching when the control mode is switched by the processing circuitry.
5. The automatic steering system according to claim 4 , wherein the processing circuitry is further configured to:
acquire the target direction of the ship and the heading of the ship, and
generate a command rudder angle based on the control parameter, taking the target direction and the heading as inputs.
6. The automatic steering system according to claim 5 , wherein the processing circuitry is further configured to:
set an unstable loop width of the ship based on a kinetic model of a body of the ship identified by using the motion information of the ship, including a command rudder angle, a heading, and a ship position.
7. The automatic steering system according to claim 6 , wherein the processing circuitry is further configured to:
set the command rudder angle to a value outside a range of the unstable loop width if the command rudder angle generated by the model-based controller is within the range of the unstable loop width.
8. The automatic steering system according to claim 7 , wherein the processing circuitry is further configured to:
refrain from outputting the command rudder angle or set the command rudder angle to a predetermined value when the command rudder angle generated by the model-based controller is within a rudder angle deadzone.
9. The automatic steering system of claim 1 , wherein the processing circuitry is further configured to:
generate the dimensionalizing motion parameter when a predetermined time elapses from a time when the dimensionalizing motion parameter is generated; and
update the control parameter based on the dimensionalizing motion parameter after the predetermined time elapses.
10. The automatic steering system according to claim 1 , wherein the processing circuitry is further configured to:
acquire a target direction of the ship and a heading of the ship,
switch the control mode of automatic navigation based on a deviation between the target direction and the heading, and
identify the non-dimensionalizing motion parameter based on the motion information of the ship acquired in the control mode before the switching when the control mode is switched by the processing circuitry.
11. The automatic steering system according to claim 1 , wherein the processing circuitry is further configured to:
acquire the target direction of the ship and the heading of the ship, and
generate a command rudder angle based on the control parameter, taking the target direction and the heading as inputs.
12. The automatic steering system according to claim 1 , wherein the processing circuitry is further configured to:
set an unstable loop width of the ship based on a kinetic model of a body of the ship identified by using the motion information of the ship, including a command rudder angle, a heading, and a ship position.
13. The automatic steering system according to claim 12 , wherein the processing circuitry is further configured to:
set the command rudder angle to a value outside a range of the unstable loop width if the command rudder angle generated by the model-based controller is within the range of the unstable loop width.
14. The automatic steering system according to claim 13 , wherein the processing circuitry is further configured to:
refrain from outputting the command rudder angle or set the command rudder angle to a predetermined value when the command rudder angle generated by the model-based controller is within a rudder angle deadzone.
15. An automatic steering method, comprising:
operating an automatic steering device to:
acquire a ship length and motion information including a ship speed;
identify a non-dimensionalizing motion parameter based on the ship length and the motion information;
generate a dimensionalizing motion parameter by dimensionalizing the non-dimensionalizing motion parameter based on the ship speed; and
set a control parameter of a model-based controller based on the dimensionalizing motion parameter; and
controlling a rudder angle based on a command rudder angle generated by the automatic steering device.
16. A non-transitory computer-readable storage medium storing processor-executable instructions that, when executed, cause one or more processors to perform the method of claim 15 .