Automatic steering device and automatic steering method

Patent metadata

Field	Value
Publication number	US-2016009351-A1
Application number	US-201314377678-A
Country	US
Kind code	A1
Filing date	Feb 5, 2013
Priority date	Feb 14, 2012
Publication date	Jan 14, 2016
Grant date	—

Abstract

The automatic steering device comprises a target rudder angle calculating unit, a target rudder angle storage unit, and a steering command unit. The target rudder angle calculating unit calculates a target rudder angle of a steering based on a heading and a target course. The target rudder angle storage unit stores a target rudder angle at a time of a previous steering command. The steering command unit outputs a steering command for instructing the steering to steer based on a newest target rudder angle calculated by the target rudder angle calculating unit and the target rudder angle at the time of the previous steering command stored by the target rudder angle storage unit.

First claim

1 . An automatic steering device comprising:
a target rudder angle calculating unit configured to calculate a target rudder angle of a steering based on a heading and a target course of a movable body; a target rudder angle storage unit configured to store the target rudder angle at a time of a previous steering command; and a steering command unit configured to output a steering command for instructing the steering to steer based on a newest target rudder angle calculated by the target rudder angle calculating unit and the target rudder angle at the time of the previous steering command stored by the target rudder angle storage unit.

2 . The automatic steering device according to claim 1 , wherein
the steering command unit is configured not to output the steering command when the target rudder angle change amount, which is a difference between the newest target rudder angle and the target rudder angle at the time of the previous steering command, is less than a prescribed steering threshold value.

3 . The automatic steering device according to claim 2 , wherein
the steering command unit includes a steering trigger output unit that is configured to output a steering trigger when the target rudder angle change amount is greater than or equal to the steering threshold value, and a steering drive processing unit that is configured to output the steering command so as to drive the steering during a prescribed steering driving time in response to the steering trigger.

4 . The automatic steering device according to claim 3 , wherein
the target rudder angle storage unit is configured to update storage content to the newest target rudder angle in response to the steering trigger.

5 . The automatic steering device according to claim 3 , further comprising
a rudder angle keep command section configured to prohibit an output of a steering trigger in a direction to turn a rudder back.

6 . The automatic steering device according to claim 5 , further comprising
an update trigger output unit configured to output an updated trigger when the steering trigger is prohibited in the direction to turn the rudder back by the rudder angle keep command section, the target rudder angle storage unit being configured to update storage content to the newest target rudder angle in response to the update trigger.

7 . The automatic steering device according to claim 5 , further comprising
a traveling state determination unit configured to determine whether or not a traveling state of the movable body is in a straight traveling state, the rudder angle keep command section being configured to prohibit the output of the steering trigger in the direction to turn the rudder back when the movable body is in the straight traveling state.

8 . The automatic steering device according to claim 3 , further comprising
a left-right balance detection unit configured to detect deviation of a steering amount to the left and right based on a difference between an average value of the heading of the movable body and the target course, and a left-right balance adjustment unit configured to adjust based on the deviation the steering driving time when steering a rudder to the right and the steering driving time when steering the rudder to the left.

9 . The automatic steering device according to claim 3 , further comprising
a steering check unit configured to detect whether or not a rudder has moved based on a change in a turning angular velocity of the movable body, and a steering driving time temporary adjustment unit configured to temporarily increase the steering driving time when the rudder is not moving even though the steering trigger has been output.

10 . An automatic steering method comprising:
calculating a target rudder angle of a steering based on a heading and a target course of a movable body; obtaining the target rudder angle at a time of a previous steering command; and selectively outputting a steering command for instructing the steering to steer based on a newest target rudder angle and the target rudder angle at the time of the previous steering command.

11 . The automatic steering method according to claim 10 , further comprising
refraining from outputting the steering command when the target rudder angle change amount, which is a difference between the newest target rudder angle and the target rudder angle at the time of the previous steering command, is less than a prescribed steering threshold value.

12 . The automatic steering method according to claim 11 , wherein
the steering command includes a steering trigger which is outputted when the target rudder angle change amount is greater than or equal to the steering threshold value, and a steering driving command so as to drive the steering during a prescribed steering driving time which is outputted in response to the steering trigger.

Assignees

• Furuno Electric Co

Inventors

• Hamamoto Kentaro

Classifications

• B63H25/36

  Rudder-position indicators · CPC title

• B63H25/06

  Steering by rudders (by rudders carrying propellers B63H25/42) · CPC title

• B63H25/04 Primary

  automatic, e.g. reacting to compass · CPC title

• B63H25/38

  Rudders · CPC title