Vessel steering apparatus
For a vessel steering apparatus for performing a movement control to move a vessel to a target position on the basis of a signal of a GPS apparatus, a movement control stop area, a buffer area adjacent to the movement control stop area, and a movement-controlling area adjacent to the buffer area are set on the basis of the distance from the target position, wherein in the movement control stop area, thrust generation by a propulsion apparatus is stopped; in the movement-controlling area, thrust is generated by the propulsion apparatus; and in the buffer area, thrust is generated by the propulsion apparatus of the vessel for movement control only in the case where the vessel moves from the movement-controlling area to the buffer area, then stays in the buffer area, and moves in a direction away from the target position.
1. A ship steering system configured to perform a movement control to move a ship to a target position, the ship steering system comprising:
a ship steering control device coupled to an ECU, the ship steering control device configured to:
determine, based on a distance between a present position of a ship calculated from a signal from a GPS device and a target position of the ship:
a movement control suspension zone including the target position,
a buffer zone adjacent to the movement control suspension zone, and
a movement control execution zone adjacent to the buffer zone,
suspend generation of a thrust by a propulsion apparatus of the ship based on the present position being in the movement control suspension zone,
generate the thrust by the propulsion apparatus of the ship based on the present position being in the movement control execution zone, and
generate the thrust by the propulsion apparatus of the ship based on the present position being in the buffer zone only when:
the ship moves from the movement control execution zone to the buffer zone, and
the ship is moving away from the target position.
2. The ship steering system according to claim 1 , wherein a size of the buffer zone is changed according to characteristics of the ship.
3. The ship steering system according to claim 1 , further comprising:
the GPS device;
a joystick lever; and
a bearing sensor.
4. The ship steering system according to claim 3 , wherein the target position comprises target coordinates having a target latitude and a target longitude.
5. The ship steering system according to claim 1 , wherein:
the ship steering control device further comprises a joystick lever; and
the ship steering control device is further configured to calculate target coordinates corresponding to the target position, the target coordinates calculated based on a signal corresponding to an operation direction and an operation amount of the joystick lever.
6. A system comprising:
an electronic control unit (ECU); and
a ship steering controller operationally coupled to the ECU and configured to:
determine a present bearing of a ship;
perform a first turning angle calculation to calculate a first turning angle based on the present bearing and a target bearing;
compare the first turning angle to a first angle and a second angle;
based on the first turning angle being less than the first angle, transmit a suspend turning control command;
based on the first turning angle being greater than or equal to the second angle, transmit a perform turning control command; and
based on the first turning angle being between the first angle and the second angle:
perform a second turning angle calculation to calculate a second turning angle based on the present bearing and the target bearing; and
transmit a perform turning control command only when:
the second turning angle is greater than the first turning angle; and
a stored turning angle is greater than or equal to the second angle.
7. The system of claim 6 , wherein the ship steering controller comprises:
a GPS device;
a bearing sensor; and
the present bearing is determined based on the bearing sensor and the GPS device.
8. The system of claim 6 , further comprising:
an engine configured to power a forward-backward propeller via a propeller shaft;
a side thruster; and
a joystick lever.
9. The system of claim 8 , wherein:
the first angle corresponds to a boundary between a control suspension zone and a buffer zone;
the second angle corresponds to a boundary between the buffer zone and a control execution zone; and
the stored turning angle immediately preceded the first turning angle by a unit time.
10. The system of claim 9 , further comprising:
a turning control configured to turn the ship via the forward-backward propeller and the side thruster; and
wherein the buffer zone comprises a range of angles between the first and second angle in which the turning control is switched between an execution state and a suspension state corresponding to an operation state based on a turning angle of the ship being included in the buffer zone.
11. The system of claim 9 , wherein the ship steering controller is further configured to:
detect an operation direction and an operation amount of the joystick lever; and
calculate the target bearing based on a signal corresponding to the operation direction and the operation amount of the joystick lever.
12. The system according to claim 9 , wherein a size of the buffer zone is changed according to characteristics of the ship.
13. A computer readable storage device comprising instructions, that when executed by a processor, cause the processor to:
calculate a first distance between a first position of a ship and a target position;
calculate a second distance between a second position of the ship and the target position
based on the second distance, generate one or more movement control zones comprising:
a movement control suspension zone between the target position and a first predetermined distance;
a buffer zone between the first predetermined distance and a second predetermined distance; and
a movement control execution zone adjacent to the buffer zone;
based on the second distance being less than the first predetermined distance, generate a suspend movement command;
based on the second distance being greater than or equal to the second predetermined distance, generate a perform movement command; and
based on the second distance being between the first predetermined distance and the second predetermined distance, generate the suspend movement command, unless:
the second distance is greater than a third distance; and
the first distance is greater than or equal to the second predetermined distance.
14. The computer readable storage device of claim 13 , wherein the processor is further configured to:
receive a third position of the ship; and
calculate the third distance between the third position of the ship and the target position.
15. The computer readable storage device of claim 13 , wherein
the movement control execution zone circumscribes the buffer zone;
the buffer zone circumscribes the movement control suspension zone; and
the movement control suspension zone circumscribes the target position.
16. The computer readable storage device of claim 13 , wherein the ship comprise a propulsion apparatus comprises one or more forward-backward propellers and a side thruster.