Boat and control method for boat system

Abstract

A boat includes a first propulsion device attached to a rear portion of a boat body to generate a propulsion force along a displaceable first axis, a second propulsion device attached to the rear portion of the boat body to generate a propulsion force along a displaceable second axis, a manual operator to indicate a movement direction of the boat body, and a controller configured or programmed to set the first and second propulsion devices to a first axial attitude in which the first and second axes intersect each other rearward of the boat body when an indicated direction is within a reference angle range including a straight-ahead direction of the boat body, and set the first and second propulsion devices to a second axial attitude in which parallelism between the first and second axes is higher than the first axial attitude when the indicated direction exceeds the reference angle range.

What is claimed is: 
     
         1 . A boat comprising:
 a boat body;   a first propulsion device attached to a port side of a rear portion of the boat body to generate a propulsion force along a first axis that is displaceable;   a second propulsion device attached to a starboard side of the rear portion of the boat body to generate a propulsion force along a second axis that is displaceable;   a manual operator to instruct a movement direction of the boat body; and   a controller configured or programmed to:
 set the first propulsion device and the second propulsion device to a first axial attitude in which the first axis and the second axis intersect each other rearward of the boat body when an indicated direction instructed by the manual operator is within a reference angle range including the straight-ahead direction of the boat body; and 
 set the first propulsion device and the second propulsion device to a second axial attitude in which parallelism between the first axis and the second axis is higher than that in the first axial attitude when the indicated direction exceeds the reference angle range. 
   
     
     
         2 . The boat according to  claim 1 , wherein the controller is configured or programmed to displace the first axis and the second axis in response to a change in the indicated direction when the indicated direction is within the reference angle range. 
     
     
         3 . The boat according to  claim 1 , wherein the controller is configured or programmed to maintain an intersection angle between the first axis and the second axis at a certain angle regardless of a change in the indicated direction when the indicated direction is within the reference angle range. 
     
     
         4 . The boat according to  claim 1 , wherein the controller is configured or programmed to displace the first axis and the second axis in response to a change in the indicated direction when the indicated direction exceeds the reference angle range. 
     
     
         5 . The boat according to  claim 1 , wherein the controller is configured or programmed to increase the parallelism between the first axis and the second axis step-by-step or continuously as an excess angle of the indicated direction exceeding the reference angle range increases when the indicated direction exceeds the reference angle range. 
     
     
         6 . The boat according to  claim 1 , wherein the second axial attitude includes an attitude in which the first axis and the second axis are parallel or approximately parallel. 
     
     
         7 . The boat according to  claim 1 , wherein the controller is configured or programmed to:
 selectively execute a first mode to set the first propulsion device and the second propulsion device to the first axial attitude when the indicated direction is within the reference angle range, and a second mode to set the first propulsion device and the second propulsion device to the second axial attitude regardless of whether the indicated direction is within the reference angle range.   
     
     
         8 . The boat according to  claim 1 , further comprising:
 a pair of guides located at the rear portion of the boat body and outside both the first propulsion device and the second propulsion device in a left-right direction of the boat body;   wherein the pair of guides are movable to a first guide attitude that extend rearwardly and toward a longitudinal center axis of the boat body.   
     
     
         9 . The boat according to  claim 8 , wherein
 the pair of guides are movable between the first guide attitude and a second guide attitude having a lower water guiding function than the first guide attitude; and   the controller is configured or programmed to:
 set the pair of guides to the first guide attitude when the indicated direction is within the reference angle range; and 
 set the pair of guides to the second guide attitude when the indicated direction exceeds the reference angle range. 
   
     
     
         10 . The boat according to  claim 1 , further comprising:
 a speed sensor to measure a movement speed of the boat; wherein   the controller is configured or programmed to:
 set the first propulsion device and the second propulsion device to the first axial direction when the indicated direction is within the reference angle range and the speed measured by the speed sensor is equal to or greater than a reference speed; and 
 set the first boat propulsion device and the second boat propulsion device to the second axial attitude when the indicated direction is within the reference angle range and the speed measured by the speed sensor is less than the reference speed. 
   
     
     
         11 . The boat according to  claim 10 , wherein the controller is configured or programmed to:
 increase the parallelism between the first axis and the second axis step-by-step or continuously as the speed measured by the speed sensor decreases when the indicated direction is within the reference angle range and the speed measured by the speed sensor is less than the reference speed.   
     
     
         12 . The boat according to  claim 1 , wherein the controller is configured or programmed to change an intersection angle between the first axis and the second axis in response to an instruction from a portable terminal operated by a user when the indicated direction is within the reference angle range. 
     
     
         13 . The boat according to  claim 1 , wherein the controller is configured or programmed to change a trim angle of at least one of the first axis or the second axis in response to an instruction from a portable terminal operated by a user when the indicated direction is within the reference angle range. 
     
     
         14 . A control method for a boat system including a first propulsion device attached to a port side of a rear portion of a boat body to generate a propulsion force along a first axis, a second propulsion device attached to a starboard side of the rear portion of the boat body to generate a propulsion force along a second axis, and a manual operator to instruct the movement direction of the boat body, the method comprising:
 setting the first propulsion device and the second propulsion device to a first axial attitude in which the first axis and the second axis intersect each other rearward of the boat body when the indicated direction by the manual operator is within a reference angle range including a straight-ahead direction of the boat body; and   setting the first propulsion device and the second propulsion device to a second axial attitude in which parallelism between the first axis and the second axis is higher than that in the first axial attitude when the indicated direction exceeds the reference angle range.   
     
     
         15 . A boat comprising:
 a boat body;   a first wake generator attached to a port side of a rear portion of the boat body to generate a flow of water along a first axis that is displaceable;   a second wake generator attached to a starboard side of the rear portion of the boat body to generate a flow of water along a second axis that is displaceable;   a manual operator to instruct a movement direction of the boat body; and   a controller configured or programmed to:
 set the first wake generator and the second wake generator to a first axial attitude in which the first axis and the second axis intersect each other rearward of the boat body when an indicated direction instructed by the manual operator is within a reference angle range including a straight-ahead direction of the boat body; and 
 set the first wake generator and the second wake generator to a third axial attitude that satisfies at least one condition that, compared to the first axial attitude, the parallelism between the first axis and the second axis is higher, or a force of a water flow is weaker when the indicated direction exceeds the reference angle range. 
   
     
     
         16 . The boat according to  claim 15 , wherein
 at least one of the first wake generator or the second wake generator includes a guide that extends in a rearward direction and toward a longitudinal center axis of the boat body;   in the first axial attitude, the guide is in an extended position protruding from the boat body; and   in the third axial attitude, the guide is in a retracted position and protrudes from the boat body less than in the extended position.