Abstract:
The disclosure relates to a marine vessel having a control system for automatically steering the marine vessel for the purpose of aiding an angler who has hooked a fish. The control system includes a GPS unit for determining the orientation of the marine vessel, a sonar unit for determining the bearing of a fish, and an algorithm for minimizing the error between the two. The control system will execute steering commands in the propulsion system in order to minimize the error in order to aid the angler as he tries to land the hooked fish.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates to automatically controlling a marine vessel in sport fishing applications. 
       BACKGROUND 
       [0002]    Sport fishing often involves a fisherman, or “angler”, using a rod and reel to catch a fish. The angler often fishes from a marine vessel in order to reach a favorable fishing location. When the angler has hooked a substantial fish, it can take a significant amount of effort by the entire crew to catch and bring aboard the fish. The angler engages in a tug-of-war with the fish as it changes location relative to the marine vessel. The operator of the boat must then maneuver the stern of the vessel so that it is oriented toward the fish in order to aid the angler as the fish moves. Typically such a vessel is equipped with special levers, known as “Palm Beach levers”, for steering the vessel during sport fishing maneuvers. These levers are located at the operator&#39;s station and are designed to be manipulated by the operator who faces the stern of the vessel while manipulating the levers behind him. This manner of maneuvering is hard to master and requires a skilled operator. 
       SUMMARY OF THE INVENTION 
       [0003]    A method for aiding an angler by automatically steering a marine vessel is proposed. The method comprises receiving a signal in an electronic controller corresponding to an orientation of the marine vessel, receiving a signal in the electronic controller corresponding to an angle of a fish relative to the marine vessel, calculating an error in the electronic controller between the orientation of the marine vessel and the angle of the fish relative to the marine vessel, generating steering commands in the electronic controller, and executing the steering commands in a marine propulsion system such that the error is minimized. 
         [0004]    In another aspect, a control system for aiding an angler by automatically steering a marine vessel is proposed. The control system comprises an electronic controller configured to receive a signal corresponding to an orientation of a marine vessel, receive a signal corresponding to an angle of a fish relative to the marine vessel, calculate an error between the orientation of the marine vessel and the angle of the fish relative to the marine vessel, generates steering commands, and a marine propulsion system for executing the steering commands such that the error is minimized. 
         [0005]    In yet another aspect, a marine vessel having a control system is proposed. The marine vessel comprises an electronic controller configured to receive a signal corresponding to an orientation of a marine vessel, receive a signal corresponding to an angle of a fish relative to the marine vessel calculate an error between the orientation of the marine vessel and the angle of the fish relative to the marine vessel, generate steering commands, and a marine propulsion system for executing the steering commands such that the error is minimized. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  shows a marine vessel and several major components according to the present disclosure 
           [0007]      FIG. 2  shows a control system according the present disclosure 
           [0008]      FIG. 3  shows a control system with additional components according to the present disclosure 
           [0009]      FIG. 4  shows a control algorithm according the present disclosure 
           [0010]      FIG. 5  shows a flowchart according the present disclosure 
       
    
    
     DETAILED DESCRIPTION 
       [0011]      FIG. 1  shows the major mechanical components of a marine vessel  10  according to the present disclosure. The marine vessel  10  includes an operator&#39;s station  35  where the major controls of the vessel are located. Such controls include control levers  36 , a joystick  37 , a keypad  120 , and a display  160 . Some or all of the controls may also be located at redundant locations such as a fly bridge  40  or a remote operator&#39;s station  45 . The marine vessel  10  also includes a marine propulsion system  69 . The marine propulsion system  69  includes, at least in part, an engine  50 , a pod  60 , and electronic controllers such as master controller  150 . The marine propulsion system  69  may also include a bow thruster  70  and/or a stern thruster  71  (not shown). The bow thruster  70  and stern thruster  71  are typically electrically driven by a controller, such as master controller  150 . They could also be powered by a hydraulic system as is known in the art (not shown). The engine  50  drives a pod  60  through a driveshaft  75 . The pod  60 , also known as an azimuth thruster, contains gearing, steering, and propulsion functions. The pod is made up of two units. The first, the pod upper unit  64 , connects to the engine  50  via the driveshaft  75  and contains the gearing and steering functions. The second, the pod lower unit  66 , mounts a propeller and provides an exhaust outlet for engine  50 . The pod lower unit  66  is external of the hull of the marine vessel  10  and rotates to provide steering. 
         [0012]    The marine vessel  10  in  FIG. 1  could contain a number of propulsion units  68  depending on the application. A propulsion unit  68  as described in this disclosure includes an engine  50  and a pod  60  along with the associated controllers  130 ,  140  and other components required for the function of the propulsion unit  68 . For instance, the marine vessel  10  in  FIG. 1  could contain two propulsion units or four propulsion units and so on. 
         [0013]    The marine vessel  10  contains at least one operator&#39;s station  35  that contains the helm and other functions of the vessel. The operator&#39;s station  35  includes a set of control levers  36  that provide input for steering and propulsion functions. A joystick  37  is also included that provides fine steering and propulsion functions. A keypad  120  provides keys or buttons or switches for various functions of the marine vessel  10 . Such functions could include engine start, engine mode, fuel system controls, lighting, fire suppression, HVAC, radio, blowers, anchor, bilge pump, generator control, external power, etc. The functions of the keypad  120  could also be fulfilled by a touch screen display or other input device known in the art. The operator&#39;s station  35  also includes a display  160  that shows that status of the various functions of the marine vessel  10 . Such functions could include engine status, engine mode, navigation, sonar, etc. The functions of the display  160  could also be fulfilled by a touch screen display. It is also conceived that functions of the keypad  120  and display  160  could be combined into a touch screen display. 
         [0014]    The marine vessel  10  may also have more than one operator&#39;s station. For instance, a redundant set of controls could be located on a fly bridge. The function of the fly bridge  40  is to give a view advantageous for navigation or pleasure viewing. Another set of controls could be located at a remote operator&#39;s station  45 . The function of the remote operator&#39;s station  45  could be to give a view advantageous for docking maneuvers. The fly bridge  40  or remote operator&#39;s station  45  could therefore have at least one of a set of control levers  36 , joystick  37 , keypad  120 , or display  160 . 
         [0015]    A GPS unit  80  is mounted to the marine vessel  10  in such a way as to receive satellite information. The GPS unit  80  consists of a receiver and any hardware needed to provide necessary location information. The GPS unit  80  is configured to provide location, heading (or orientation), and velocity information. The GPS unit  80  may provide an analog output or may be configured to provide a message containing location information onto a control area network (CAN). The GPS unit  80  according to this disclosure could be configured to work with the GPS, GLONASS, or other satellite location system. 
         [0016]    Similarly, a sonar unit  90  is mounted to the marine vessel  10  in such a way as to provide location of an underwater target, e.g. a fish  22 . The sonar unit  90  is configured to provide distance and bearing of the fish  22 . The sonar unit  90  may provide an analog output or may be configured to provide a message containing target information onto a control area network (CAN). 
         [0017]    A fisherman, or angler  20 , typically fishes from the deck at the stern of the marine vessel  10 . Typical angling equipment includes a rod and reel. The reel includes a fishing line with an angled hook at the end for holding bait and hooking a fish  22 . The angler  20  may fish from either a seated or standing position. If a substantial fish  22  is hooked, the angler  20  can experience considerable force as the angler  20  is pulled in the direction of the fish  22 . If the angler  20  is seated then the forces from the fish  22  are transmitted into the angler&#39;s seat  25 . 
         [0018]    An angler&#39;s seat  25  may be located on the stern of the marine vessel  10 . The seat  25  is attached to the deck by a seat support  26 . The seat  25  may be a single column or multiple legs as is known in the art. A load cell  110 , such as a strain gage ring, is attached to the seat support in a manner such that forces on the angler  20  seated on the seat  25  are transmitted to the support  26  and are detected by the load cell. An example of a suitable load cell  110  is a TS Load Cell sold by MAGPOWR of Oklahoma City, Okla. A strain gage ring is capable of detecting a force in any direction along the horizontal plain. The load cell  110  is therefore capable of sensing forces applied by a hooked fish  22  to an angler  20 , and on to the angler&#39;s seat  25 . The output from the load cell  110  is passed to a controller, such as the master controller  150 . The controller is capable of discerning natural movement of the angler  20  versus movement of the angler  20  when a fish  22  has been hooked. For instance, natural movement of the angler  20  would be indicated by small forces in rapidly changing directions as the angler  20  shifts position in the angler&#39;s seat  25 . In contrast, the movement of the angler when a fish  22  has been hooked would be indicated by larger forces that change direction less rapidly. The controller is able use this information to determine whether the angler  20  is engaged with a fish  22  or not. 
         [0019]      FIG. 2  shows a diagrammatic view of a control system according to the present disclosure. A master controller  150  is connected via a control area network (CAN)  155   a . The CAN is of the type that is commonly known in the art, such as J1939. The master controller  150  is connected via CAN  155   a  to the pod controller  130 . Control levers  36 , joystick  37 , and keypad  120  are also connected to CAN  155   a . These devices are configured to generate messages on the CAN  155   a  corresponding to their inputs. GPS unit  80  may also connected to CAN  155   a . The GPS unit  80  is configured to deliver messages corresponding to location and orientation information to master controller  150 . The GPS unit  80  could also be connected to master controller  150  via an analog or digital connection in order to provide the same information. 
         [0020]    The sonar unit  90  may be connected to CAN  155   a  or it may be connected to master controller  150  via an analog or digital connection. The sonar unit  90  is configured to deliver information regarding range and bearing information of a target fish  22 . 
         [0021]    Given the input from the GPS unit  80  and the sonar unit  90 , the master controller  150  can compare the orientation of the marine vessel  10  to the bearing of the fish  22 . 
         [0022]    A bow thruster  70  or a stern thruster  71  is optional and can be included as the application requires. The bow thruster  70  and stern thruster  71  are typically electrically driven by a controller, such as master controller  150 . They could also be powered by a hydraulic system as is known in the art (not shown). 
         [0023]    The control system in  FIG. 2  shows two propulsion units  68 . A propulsion unit  68  as described in this disclosure includes an engine  50  and a pod  60  along with the associated controllers  130 ,  140  and other components required for the function of the propulsion unit  68 . It is also conceived within the scope of this disclosure that other propulsion units  68  could be added to the control system. For instance, the control system in  FIG. 3  shows a control system including four propulsion units  68 . Any number of propulsion units  68  can be included by adding the appropriate CAN connections and components. 
         [0024]    The pod controller  130  is connected to pod  60  and an engine controller  140  via a control area network (CAN)  155   b . The pod controller  130  communicates with and issues steering and gear change commands to the pod  60 . The pod controller  130  also communicates with and issues commands to the engine controller  140 . Commands could include such parameters as speed, torque, start/stop, etc. Multiple pod controllers  130  may be linked by a separate control area network (CAN)  155   c.    
         [0025]      FIG. 4  shows a general depiction of a PID control algorithm according the present disclosure. The PID control algorithm is executed in a controller, such as master controller  150 . The bearing of the target fish  22  from sonar unit  90  serves as the input desired angle  170 . Orientation of the marine vessel  10  from the GPS unit  80  serves as the measured angle  180 . The difference between  170  and  180  is defined as the angle error  190  which is fed into the PID control  200 . The PID controller contains any or all of a proportional, integral, or derivative term as is well known in the art. The output of the PID control  200  then serves as input to the process  210 , which represents the dynamics of the steering and propulsion systems and interactions of the marine vessel  10 . The output of process  210  serves as the appropriate commands to the pod controllers  130 . 
         [0026]      FIG. 5  depicts an example of a method of implementing the control system in the present disclosure. The method begins at box  300 . The method moves next to decision box  310 . If YES at  310  the method moves to decision box  320 . If NO at  310  the method moves to decision box  400 . If YES at  320  the method moves to action box  380  where Sportfish Mode is deactivated. The method then returns to decision box  310 . If NO at  320  then the method moves to decision box  330 . If YES at  330  the method moves to action box  380 . The method moves from  380  to decision box  310 . If NO at  330  the method moves to decision box  340 . If YES at  340  the method moves to decision box  350 . If NO at  340  the method moves to action box  390 . If YES at  350  the method moves to action box  360  where automatic control of the marine vessel  10  is executed. The method moves from  360  to decision box  370 . If NO at  350  the method moves to action box  390 . The method moves from action box  390  to decision box  370 . 
         [0027]    If YES at  400  the method moves to either of action boxes  410  and  420 , depending on how long the keypad button is pressed. If the key at  400  is pressed for less than 2 seconds, the method moves to  420 , where Sportfish Mode is enabled. If the key at  400  is pressed for more than 2 seconds, the method moves to  410  where Sportfish Mode is enabled without load cell  110  functionality. The method moves from  420  to decision box  320 . 
         [0028]    The method moves from  410  to decision box  440 . If YES at  440  the method moves to action box  460 . If NO at  440  the method moves to decision box  450 . If YES at  450  the method moves to  460 . If YES at  450  the method moves to action box  460 . If NO at  450  the method moves to decision box  470 . If YES at  470  the method moves to action box  500  where automatic control of the marine vessel  10  is executed. The method moves from  500  to decision box  490 . If NO at  470  the method moves from action box  480 . The method moves from  480  to  490 . If YES at  490  the method moves to  460 . If NO at  490  the method moves to  310 . 
       INDUSTRIAL APPLICABILITY 
       [0029]    The present disclosure relates to a method and control system for steering a marine vessel  10 . The marine vessel  10  is a vessel that is specially equipped for sport fishing, or angling. The vessel is equipped with a GPS unit  80  for navigation and a sonar unit  90  for detecting a target fish  22 . The marine vessel  10  includes a small crew, including a captain, in addition to the angler  20 . The captain of the ship often serves as the operator of the marine vessel  10 . The captain operates the vessel from the helm while the angler  20  is typically located at the stern of the marine vessel  10 . 
         [0030]    The operator will typically operate the marine vessel  10  in a low speed cruise mode while the angler  20  is actively fishing. The operator will then push a sportfishing mode key on the keypad  120  in order to enable a special sportfishing mode. When the key is pressed for 100 ms, an LED next to the key (or backlighting the key) will turn on indicating that that the sportfishing mode is active. Pressing the key for 100 ms while the sportfishing mode is active will deactivate the sportfishing mode. The sportfishing mode will also be deactivated if the operator moves any of the helm controls or if communication between the master controller  150  and the keypad  120  is lost. 
         [0031]    Once the sporfishing mode is active, the controllers  130 ,  140 , or  150  may check to determine whether any sensor faults are active. If any faults are active, the sportfishing mode will be deactivated. 
         [0032]    Pressing the sportfishing mode key for 2 seconds will also activate the sportfishing mode feature but without regard to the signal from the load cell  110  on the angler&#39;s seat  25 . This allows the sportfishing mode to operate without requiring the angler  20  to stay seated. In this way, the angler  20  is free to move about the stern of the marine vessel  10  while still benefiting from the automatic steering of the sportfishing mode. 
         [0033]    When all the requirements are met, the automatic sportfishing mode will engage and take command of the marine propulsion system  69 . The master controller receives data regarding the orientation of the marine vessel  10  from the GPS unit  80 . The master controller receives data regarding the bearing of the target fish  22  from the sonar unit  90 . The angle error  190  between the two is calculated and then enters into a PID control  200 . Commands to the marine propulsion system  69  are executed such that angle error  190  is minimized. For example, suppose that the GPS unit  80  indicates that the stern of the marine vessel  10  is oriented toward a compass reading of 0 degrees. Suppose also that the sonar unit  90  indicates that a target fish  22  is located at a compass reading of 20 degrees. The master controller  150  calculates the error as 20 degrees and issues commands to the rest of the marine propulsion system  69  to cause the stern of the marine vessel  10  to point at the target fish  22 . 
         [0034]    The pods  60  in the marine propulsion system  69  work together in order to increase the steering response of the marine vessel  10 . For instance, a two pod system may have each pod  60  thrusting in opposite directions during sportfishing mode. The pods  60  could also thrust in the same direction in order to combine their thrust. The marine propulsion system  69  can also include a bow thruster  70  or a stern thruster  71  that can include propulsion and steering in addition to the pods  60 . 
         [0035]    The parameters of the PID control  200  are set as is known in the art. The proportional term is set to be the amount of correction as needed at the time the error is measured and can be tuned as needed. The integral term is the sum of the error over time, while the derivative term is the prediction of future error based on the current rate of change.