Marine vessel and control device therefor

Abstract

A control device for a marine vessel includes a hull, a pair of water resistance bodies, and a controller. The pair of water resistance bodies are provided on the hull, one on a left side and one on a right side of the hull, each independently movable between a first position in which a resistance received from water in a predetermined direction is adjustable to a first magnitude, and a second position in which a resistance is adjustable to zero or to a second magnitude smaller than the first magnitude. The controller is configured or programmed to acquire a relative distance between a buoy, which floats on the water in a free-drifting manner, and the hull. The controller is configured or programmed to control the pair of water resistance bodies based on the relative distance.

What is claimed is: 
     
         1 . A control device for a marine vessel, the control device comprising:
 a hull;   a pair of water resistance bodies on the hull, one on a left side and one on a right side of the hull, each independently movable between a first position in which a resistance received from water in a predetermined direction is adjustable to a first magnitude, and a second position in which a resistance is adjustable to zero or to a second magnitude smaller than the first magnitude; and   a controller configured or programmed to:
 acquire a relative distance between a buoy, which floats on the water in a free-drifting manner, and the hull; and 
 control the pair of water resistance bodies based on the relative distance. 
   
     
     
         2 . The control device according to  claim 1 , wherein the controller is configured or programmed to set the pair of water resistance bodies to the second position when the relative distance is greater than a first distance and is equal to or less than a second distance that is greater than the first distance. 
     
     
         3 . The control device according to  claim 2 , wherein the controller is configured or programmed to set one of the pair of water resistance bodies to the first position and another one of the pair of water resistance bodies to the second position when a relative orientation of the buoy with respect to the hull deviates from a target relative orientation by more than a predetermined angle, even if the relative distance is greater than the first distance and is equal to or less than the second distance. 
     
     
         4 . The control device according to  claim 2 , wherein the controller is configured or programmed to set at least one of the pair of water resistance bodies to the first position when the relative distance is greater than the second distance. 
     
     
         5 . The control device according to  claim 4 , wherein the controller is configured or programmed to set the pair of water resistance bodies to the first position when the relative distance is greater than the second distance and a relative orientation of the buoy with respect to the hull does not deviate from a target relative orientation by more than a predetermined angle. 
     
     
         6 . The control device according to  claim 4 , wherein the controller is configured or programmed to set one of the pair of water resistance bodies to the first position and another one of the pair of water resistance bodies to the second position when the relative distance is greater than the second distance and a relative orientation of the buoy with respect to the hull deviates from a target relative orientation by more than a predetermined angle. 
     
     
         7 . The control device according to  claim 2 , wherein the controller is configured or programmed to correct a position of the hull using two or more propulsion devices when the relative distance is equal to or less than the first distance. 
     
     
         8 . The control device according to  claim 2 , wherein the controller is configured or programmed to correct a position of the hull using two or more propulsion devices when the relative distance is greater than a third distance that is greater than the second distance. 
     
     
         9 . The control device according to  claim 8 , wherein the controller is configured or programmed to correct the position of the hull using the two or more propulsion devices when a state in which the relative distance is greater than the second distance and is equal to or less than the third distance has continued for more than a predetermined time. 
     
     
         10 . The control device according to  claim 1 , wherein the buoy is connected to the hull by a connector. 
     
     
         11 . The control device according to  claim 1 , wherein the predetermined direction corresponds to a front-rear direction of the hull. 
     
     
         12 . The control device according to  claim 11 , wherein
 the water resistance bodies are each configured to pivot about a pivot shaft parallel to an up-down direction;   the first position is a position where the water resistance bodies are perpendicular to the front-rear direction of the hull; and   the second position is a position where the water resistance bodies are parallel to the front-rear direction of the hull.   
     
     
         13 . The control device according to  claim 1 , wherein
 the buoy is configured to output information indicating a position thereof; and   the controller is configured or programmed to acquire the relative distance based on a position of the hull and the information output from the buoy.   
     
     
         14 . The control device according to  claim 4 , further comprising at least one sensor to detect the relative distance between the buoy and the hull. 
     
     
         15 . The control device according to  claim 1 , wherein each of the pair of water resistance bodies is plate-shaped. 
     
     
         16 . The control device according to  claim 1 , further comprising:
 a pair of water resistance assemblies each including:
 a rotary motor to move one of the pair of water resistance bodies between the first position and the second position; and 
 a lifting motor to move one of the pair of water resistance bodies up and down relative to the hull. 
   
     
     
         17 . A marine vessel comprising:
 the control device according to  claim 1 .