Marine propulsion system and marine vessel

Abstract

A marine propulsion system includes a controller configured or programmed to perform an in-wave vessel speed control such that a vessel speed becomes equal to or higher than a predetermined minimum vessel speed in an in-wave vessel speed control mode in which an in-wave vessel speed control is performed to adjust the vessel speed based on information regarding upward-downward movement of a hull.

What is claimed is: 
     
         1 . A marine propulsion system comprising:
 a propulsion device to be on or in a hull; and   a controller configured or programmed to control driving of the propulsion device to adjust a vessel speed, and perform an in-wave vessel speed control to adjust the vessel speed based on information regarding upward-downward movement of the hull; wherein   the controller is configured or programmed to perform the in-wave vessel speed control such that the vessel speed becomes equal to or higher than a predetermined minimum vessel speed in an in-wave vessel speed control mode in which the in-wave vessel speed control is performed.   
     
     
         2 . The marine propulsion system according to  claim 1 , wherein the predetermined minimum vessel speed is equal to or higher than a minimum speed at which the hull is able to plane in the in-wave vessel speed control mode. 
     
     
         3 . The marine propulsion system according to  claim 1 , wherein the controller is configured or programmed to perform a notification control to notify a vessel user that the vessel speed has become the predetermined minimum vessel speed when the vessel speed has become the predetermined minimum vessel speed in the in-wave vessel speed control mode. 
     
     
         4 . The marine propulsion system according to  claim 1 , wherein the controller is configured or programmed to increase a change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined vessel speed threshold that is greater than the predetermined minimum vessel speed by a predetermined amount in the in-wave vessel speed control mode. 
     
     
         5 . The marine propulsion system according to  claim 4 , wherein the controller is configured or programmed to:
 perform the in-wave vessel speed control based on a value obtained by averaging the information regarding upward-downward movement of the hull over a predetermined period of time; and   reduce the predetermined period of time during which the averaging is performed to increase the change in the vessel speed when the vessel speed becomes equal to or lower than the predetermined vessel speed threshold in the in-wave vessel speed control mode.   
     
     
         6 . The marine propulsion system according to  claim 5 , wherein the controller is configured or programmed to, in the in-wave vessel speed control mode, change the predetermined period of time during which the averaging is performed to a first period of time so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined first vessel speed threshold, and change the predetermined period of time during which the averaging is performed to a second period of time that is longer than the first period of time when the vessel speed becomes equal to or higher than a predetermined second vessel speed threshold that is greater than the predetermined first vessel speed threshold after becoming equal to or lower than the predetermined first vessel speed threshold. 
     
     
         7 . The marine propulsion system according to  claim 4 , wherein the controller is configured or programmed to:
 perform the in-wave vessel speed control based on a value obtained by averaging the information regarding upward-downward movement of the hull over a predetermined period of time; and   change a weighting coefficient to adjust a weighting of the information regarding upward-downward movement of the hull such that a weighting of a latest value of the information regarding upward-downward movement of the hull is greater than a weighting of other than the latest value of the information regarding upward-downward movement of the hull so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than the predetermined vessel speed threshold in the in-wave vessel speed control mode.   
     
     
         8 . The marine propulsion system according to  claim 7 , wherein the controller is configured or programmed to, in the in-wave vessel speed control mode, change the weighting coefficient to a first weighting value such that the weighting of the latest value of the information regarding upward-downward movement of the hull is greater than the weighting of other than the latest value of the information regarding upward-downward movement of the hull so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined first vessel speed threshold, and change the weighting coefficient to a second weighting value such that the weighting of the latest value of the information regarding upward-downward movement of the hull is smaller as compared with a case in which the vessel speed is equal to or lower than the predetermined first vessel speed threshold when the vessel speed becomes equal to or higher than a predetermined second vessel speed threshold that is greater than the predetermined first vessel speed threshold after becoming equal to or lower than the predetermined first vessel speed threshold. 
     
     
         9 . The marine propulsion system according to  claim 4 , wherein the controller is configured or programmed to:
 perform the in-wave vessel speed control based on a value obtained by averaging the information regarding upward-downward movement of the hull over a predetermined period of time; and   decrease a parameter to be averaged to increase the change in the vessel speed when the vessel speed becomes equal to or lower than the predetermined vessel speed threshold in the in-wave vessel speed control mode.   
     
     
         10 . The marine propulsion system according to  claim 9 , wherein the controller is configured or programmed to, in the in-wave vessel speed control mode, change the parameter to be averaged to a first parameter value so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined first vessel speed threshold, and change the parameter to be averaged to a second parameter value that is greater than the first parameter value when the vessel speed becomes equal to or higher than a predetermined second vessel speed threshold that is greater than the predetermined first vessel speed threshold after becoming equal to or lower than the predetermined first vessel speed threshold. 
     
     
         11 . The marine propulsion system according to  claim 4 , wherein the controller is configured or programmed to increase a maximum value of a rate of change of the vessel speed so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than the predetermined vessel speed threshold in the in-wave vessel speed control mode. 
     
     
         12 . The marine propulsion system according to  claim 11 , wherein the controller is configured or programmed to, in the in-wave vessel speed control mode, change the maximum value of the rate of change of the vessel speed to a first maximum value of the rate of change so as to increase the change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined first vessel speed threshold, and change the maximum value of the rate of change of the vessel speed to a second maximum value of the rate of change that is smaller than the first maximum value of the rate of change when the vessel speed becomes equal to or higher than a predetermined second vessel speed threshold that is greater than the predetermined first vessel speed threshold after becoming equal to or lower than the predetermined first vessel speed threshold. 
     
     
         13 . The marine propulsion system according to  claim 1 , wherein the controller is configured or programmed to perform the in-wave vessel speed control based on a moving average value obtained by averaging the information regarding upward-downward movement of the hull over a predetermined period of time. 
     
     
         14 . The marine propulsion system according to  claim 3 , further comprising:
 an operator to receive an operation from the vessel user; wherein   the controller is configured or programmed to, in the in-wave vessel speed control mode, perform the notification control when the vessel speed has become the predetermined minimum vessel speed, and change the predetermined minimum vessel speed when the vessel user operates the operator to change the predetermined minimum vessel speed.   
     
     
         15 . The marine propulsion system according to  claim 14 , wherein the controller is configured or programmed to, in the in-wave vessel speed control mode, perform the notification control when the vessel speed has become the predetermined minimum vessel speed, and increase the predetermined minimum vessel speed when the vessel user operates the operator to increase the predetermined minimum vessel speed. 
     
     
         16 . The marine propulsion system according to  claim 14 , wherein the controller is configured or programmed to return a changed predetermined minimum vessel speed to an initial value when the controller is powered off or restarted in the in-wave vessel speed control mode. 
     
     
         17 . A marine vessel comprising:
 a hull; and   a marine propulsion system on or in the hull and including:
 a propulsion device on or in the hull; and 
 a controller configured or programmed to control driving of the propulsion device to adjust a vessel speed, and perform an in-wave vessel speed control to adjust the vessel speed based on information regarding upward-downward movement of the hull; wherein 
   the controller is configured or programmed to perform the in-wave vessel speed control such that the vessel speed becomes equal to or higher than a predetermined minimum vessel speed in an in-wave vessel speed control mode in which the in-wave vessel speed control is performed.   
     
     
         18 . The marine vessel according to  claim 17 , wherein the predetermined minimum vessel speed is equal to or higher than a minimum speed at which the hull is able to plane in the in-wave vessel speed control mode. 
     
     
         19 . The marine vessel according to  claim 17 , wherein the controller is configured or programmed to perform a notification control to notify a vessel user that the vessel speed has become the predetermined minimum vessel speed when the vessel speed has become the predetermined minimum vessel speed in the in-wave vessel speed control mode. 
     
     
         20 . The marine vessel according to  claim 17 , wherein the controller is configured or programmed to increase a change in the vessel speed when the vessel speed becomes equal to or lower than a predetermined vessel speed threshold that is greater than the predetermined minimum vessel speed by a predetermined amount in the in-wave vessel speed control mode.