Method for operating a steering unit for a steer-by-wire ship's control system

Abstract

A method of operating a steering unit for a steer-by-wire ship control system, comprising a steering wheel, a controller that is connected to the electronic controller of the steer-by-wire ship control system (ECU), a sensor for detecting the angular position of the steering wheel, and a device for generating mechanical resistance at the steering wheel. The mechanical resistance generated at the steering wheel, by the device for generating mechanical resistance at the steering wheel upon actuation of the steering wheel by an operator, depends on the speed of the engine or ship. The resistance is raised as the speed increases until a predetermined threshold is reached. If an auto-pilot device is activated, then the mechanical resistance has a constant value at every speed.

1 - 6 . (canceled) 
     
     
         7 . A method of operating a steering unit for a steer-by-wire ship control system, in which the steering unit comprises a steering wheel, a controller that is connected to an electronic controller of a ship control system (ECU), a sensor for detecting the angular position of the steering wheel, and a device for generating mechanical resistance at the steering wheel, the method comprising the steps of:
 generating the mechanical resistance at the steering wheel by the device for generating mechanical resistance at the steering wheel upon actuation of the steering wheel by an operator depends on speed of the ship;   raising the mechanical resistance at the steering wheel as the speed of the ship increases until a predetermined threshold value is reached; and   if an auto-pilot device is activated, maintaining the mechanical resistance at a constant value for every speed.   
     
     
         8 . The method of operating a steering unit for a steer-by-wire ship control system according to  claim 7 , further comprising the steps of defining a speed, below which no mechanical resistance is generated by pivoting the steering wheel, and above this speed, the mechanical resistance generated by the device for generating mechanical resistance at the steering wheel is increased up to a predetermined threshold value as a function of the speed. 
     
     
         9 . A method of operating a steering unit for a steer-by-wire ship control system in which the steering unit comprises a steering wheel, a controller that is connected to an electronic control unit of a ship control system (ECU), a sensor for detecting the angular position of the steering wheel, and a device for generating mechanical resistance at the steering wheel, the method comprising the steps of:
 defining a non-reset zone, a reset zone, and a boundary zone in a range of angular positions of the steering wheel with respect to a current zero-position of the steering wheel (which is to say the starting position before performing a steering movement), if the steering unit has a device for resetting the steering wheel;   if the angular position of the steering wheel, during a steering actuation by an operator, is within the non-reset zone, then delaying resetting the steering wheel to the current zero-position of the steering wheel;   if the angular position of the steering wheel, after a steering actuation by the operator, is within the reset zone, then resetting the steering wheel with the device for resetting the steering wheel at a constant speed to either the current zero-position of the steering wheel, or a position in the non-reset zone; and   if the angular position of the steering wheel, after a steering actuation by the operator, is within the boundary zone, then operating the device for resetting the steering wheel such that the steering wheel either cannot be moved further in a direction of the steering movement, or can only be moved in the direction of the steering movement with considerable force, and is reset at a constant speed to either a defined angular position within the reset zone or a defined position within the non-reset zone.   
     
     
         10 . The method of operating a steering unit for a steer-by-wire ship control system according to  claim 9 , further comprising the steps of:
 defining the non-reset zone as an angular region between +1° and 135° around the current zero-position of the steering wheel (which is to say the starting position before performing the steering movement);   defining the reset zone as angular regions between ends of the non-reset zone and 45 to 95% of a maximum possible number of steering wheel revolutions in a clockwise and a counterclockwise direction; and   defining the boundary zone as angular regions between 45 to 95% and 100% of a maximum possible number of steering wheel revolutions in the clockwise and the counterclockwise direction.   
     
     
         11 . The method of operating a steering unit for a steer-by-wire ship control system according to  claim 9 , further comprising the steps of:
 depending on a speed of the ship, if no auto-pilot device is activated, increasing the mechanical resistance generated at the steering wheel up a predetermined threshold value, and the mechanical resistance being generated at the steering wheel by the device for generating mechanical resistance during an actuating of the steering wheel by the operator in either the reset zone and the non reset-zone; and   maintaining the mechanical resistance at a constant predetermined value at every speed of the ship, if an auto-pilot device is activated, and in the boundary zone, the mechanical resistance is either at a constant maximum value or is increase up to the maximum value, depending on a number of revolutions to go before achieving the maximum possible number of steering wheel revolutions.   
     
     
         12 . The method of operating a steering unit for a steer-by-wire ship control system according to  claim 11 , further comprising the steps of:
 defining a speed, below which no mechanical resistance is generated by movement of the steering wheel and, above this speed, the mechanical resistance is increased up to a predetermined threshold value, as a function of the speed, if no auto-pilot device is activated, and the angular position of the steering wheel is within either the reset zone or the non-reset zone.