Patent Description:
<CIT> discloses a trolling motor system comprising a trolling motor having a propeller rotatably driven thereby. The motor is connected to a rotating tube or column mounted to the boat. A control head is mounted at the upper end of the column. A steering motor in the control head controls rotational position of the trolling motor. The control head houses a control circuit for controlling speed of the trolling motor as well as position of the steering motor to steer the boat. A foot pedal is positioned in the boat in proximity to the control head. The foot pedal includes a plurality of user actuable switches for commanding operation of the steering motor and trolling motor. The commands are transmitted via radio frequency to a receiver in the control head. The receiver decodes the commands and transfers the command to the control circuit.

<CIT> discloses a control system for a marine vessel that incorporates a marine propulsion system that can be attached to a marine vessel and connected in signal communication with a serial communication bus and a controller. A plurality of input devices and output devices are also connected in signal communication with the communication bus and a bus access manager, such as a CAN Kingdom network, is connected in signal communication with the controller to regulate the incorporation of additional devices to the plurality of devices in signal communication with the bus whereby the controller is connected in signal communication with each of the plurality of devices on the communication bus. The input and output devices can each transmit messages to the serial communication bus for receipt by other devices.

<CIT> discloses a touch screen that may be utilized by a marine electronic device to easily enter a route in relation to a chart. The marine electronic device may automatically determine and join geographic points associated with the chart to generate a route based on a touch pattern. The marine electronic device may be configured to complete the route to form a route loop in instances in which the start and end of the touch pattern are within a predetermined distance. The completion of the route may be accomplished by connecting the end point to the start point or by "snapping" the end point to the start point, e.g. shifting the end point to the start point. Additionally or alternatively, a user may use pre-determined route snippets to quickly and easily alter a route.

<CIT> discloses a method of operating a wireless lanyard system on a marine vessel having at least one propulsion device including defining a permitted zone with respect to a helm area where an operator should occupy based on one or more conditions of the marine vessel. Generating a location inquiry signal by a helm transceiver at the helm area of the marine vessel, and receiving an operator location signal from an operator fob worn by the operator of the marine vessel in response to the location inquiry signal. The method further includes determining whether the operator is within the permitted zone with respect to the helm area based on the operator location signal, and generating a lanyard event when the operator is not within the permitted zone. Upon generation of the lanyard event, the propulsion device is controlled to reduce an engine RPM to an idle RPM or the propulsion device is turned off.

<CIT> discloses many different types of systems that are utilized or tasks are performed in a marine environment. The present invention provides various configurations of unmanned vehicles, or drones, that can be operated and/or controlled for such systems or tasks. One or more unmanned vehicles can be integrated with a dedicated marine electronic device of a marine vessel for autonomous control and operation. Additionally or alternatively, the unmanned vehicle can be manually remote operated during use in the marine environment. Such unmanned vehicles can be utilized in many different marine environment systems or tasks, including, for example, navigation, sonar, radar, search and rescue, video streaming, alert functionality, among many others. However, as contemplated by the present invention, the marine environment provides many unique challenges that may be accounted for with operation and control of an unmanned vehicle.

<CIT> discloses a vessel control system for a marine vessel propelled by at least one propulsion device including a wireless lanyard system including at least one fob worn by an individual on the marine vessel and a helm transceiver at a helm area of the marine vessel configured to receive radio signals from the at least one fob. A controller is configured to detect, based on communications between each of the at least one fob and the helm transceiver, that each of the at least one fob is present on the marine vessel. A missing fob is detected if at least one of the fobs is no longer detected at the helm transceiver, and then a man overboard event is generated. The vessel control system is configured to automatically activate one or more search assistance functions based on the man overboard event.

<CIT> discloses a system for automatically controlling the navigation of a ship. The system comprises a man overboard detection function.

According to one example of the present disclosure, a system for a marine vessel propelled by a propulsion device includes a controller operable in an automatic navigation mode in which the controller automatically controls a thrust of the propulsion device to propel the marine vessel through a body of water. A portable device is configured to be carried on an individual on the marine vessel. The controller enables a person overboard detection algorithm in response to enablement of the automatic navigation mode. The person overboard detection algorithm disables the automatic navigation mode in response to detecting a given status of the portable device.

In one example, a receiver is in signal communication with the controller. In such an example, the portable device comprises a transmitter and the given status of the portable device relates to a signal strength of the transmitter as received by the receiver. In one example, the person overboard detection algorithm disables the automatic navigation mode in response to detecting an abrupt change in the received signal strength of the transmitter.

In one example, the portable device further comprises an accelerometer and the person overboard detection algorithm disables the automatic navigation mode in response to an abrupt change in acceleration of the portable device as determined by the accelerometer.

In one example, the given status of the portable device is that the portable device is not physically connected to a switch in signal communication with the controller. In one example, the switch is movable onboard the marine vessel while still maintaining signal communication with the controller.

In one example, the person overboard detection algorithm controls the propulsion device to cause the marine vessel to backtrack along an immediately prior course of the marine vessel in response to detecting the given status of the portable device.

In one example, the person overboard detection algorithm controls the propulsion device to reduce the thrust thereof in response to determining that the marine vessel is within a given range of the portable device subsequent to having been outside the given range of the portable device.

In one example, the person overboard detection algorithm controls the propulsion device to stop producing thrust in response to detecting the given status of the portable device.

In one example, the portable device is a remote control configured to allow the individual to control the thrust of the propulsion device.

According to another example of the present disclosure, a method for controlling a propulsion device on a marine vessel includes enabling an automatic navigation mode in which a thrust of the propulsion device is controlled automatically to propel the marine vessel through a body of water. The method includes enabling a person overboard detection algorithm in response to enablement of the automatic navigation mode. The method also includes disabling the automatic navigation mode in response to the person overboard detection algorithm determining that an individual on the marine vessel may have fallen overboard.

In one example, the step of determining that the individual on the marine vessel may have fallen overboard comprises detecting a given status of a portable device configured to be carried on the individual and in signal communication with a controller of the propulsion device.

In one example, the portable device comprises a transmitter and the given status of the portable device relates to a signal strength of the transmitter as received by a receiver in signal communication with the controller.

In one example, the method includes disabling the automatic navigation mode in response to detecting an abrupt change in the received signal strength of the transmitter.

In one example, the method includes disabling the automatic navigation mode in response to an abrupt change in acceleration of the portable device as determined by an accelerometer in the portable device.

In one example, the method includes controlling the propulsion device to cause the marine vessel to backtrack along an immediately prior course of the marine vessel in response to determining that the individual on the marine vessel may have fallen overboard.

In one example, the method includes reducing the thrust of the propulsion device in response to determining that the marine vessel is within a given range of the individual subsequent to having been outside the given range of the individual.

In one example, the method includes discontinuing thrust production by the propulsion device in response to determining that the individual on the marine vessel may have fallen overboard.

The same numbers are used throughout the Figures to reference like features and like components.

<FIG> shows a marine vessel <NUM>. The marine vessel <NUM> is capable of operating, for example, in a normal operating mode and at least one automatic navigation mode as will be described further herein below. The marine vessel <NUM> has a primary propulsion device <NUM> located at its stern and a secondary propulsion device (trolling motor assembly <NUM>) located at its bow. As illustrated, the primary propulsion device <NUM> is an outboard motor; however, the primary propulsion device <NUM> could be any one of an inboard motor, a stern drive, a pod drive, a jet drive, a thruster, or any other marine propulsion device as appropriate for its location. Each propulsion device <NUM>, <NUM> is steerable about its respective steering axis <NUM>, <NUM> and produces thrust by causing rotation of its respective propeller or other propulsor, as the case may be.

The marine vessel <NUM> also includes various control elements that together with the propulsion devices <NUM>, <NUM> make up a marine propulsion system <NUM>. The marine propulsion system <NUM> comprises an operation console <NUM> in communication with a controller <NUM> via a controller area network (CAN) bus <NUM> as described in <CIT>. The controller <NUM> includes a processing system <NUM>, a storage system <NUM> accessible by the processing system <NUM>, and an input/output (I/O) interface <NUM>, which relays information to and from the processing system <NUM>. The processing system <NUM> can comprise a microprocessor, including a control unit and a processing unit, and other circuitry, such as semiconductor hardware logic, that retrieves and executes software from the storage system <NUM>. The storage system <NUM> can comprise any storage media readable by the processing system <NUM> and capable of storing software. The storage system <NUM> can include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, software modules, or other data. The processing system <NUM> loads and executes software from the storage system <NUM>, such as software programmed with one or more automatic navigation algorithms and software programmed with a person overboard detection algorithm, which direct the processing system <NUM> to operate as described herein below in further detail. In one example, the controller <NUM> is (or is part of) a helm control module, a propulsion control module, or other known module for use on a marine vessel <NUM>. Note that the controller <NUM> is not shown as being connected to every component in the diagrams provided herein, but the controller <NUM> is in fact directly or indirectly electrically and/or signally connected to each component that it is described as controlling or from which it receives information.

The operation console <NUM> includes a number of user input devices, such as a marine electronic device <NUM> (e.g., a chart plotter, a fish finder, a multi-function display, or other dedicated device), a joystick <NUM>, a steering wheel <NUM>, and a shift/speed lever <NUM>. Each of these user input devices may provide a request for movement of the marine vessel <NUM> to the controller <NUM> via the I/O interface <NUM>. The steering wheel <NUM> and the shift/speed lever <NUM> function in the conventional manner. For example, rotation of the steering wheel <NUM> may activate a transducer that provides a signal to the controller <NUM> regarding a desired movement of the marine vessel <NUM>. The controller <NUM> in turn sends signals to activate steering actuators to achieve desired orientations of the primary propulsion device <NUM> about its respective steering axis <NUM> as known in the art. The shift/speed lever <NUM> sends signals to the controller <NUM> regarding the desired shift or direction of movement (forward, reverse, or neutral) and the desired magnitude of thrust for the primary propulsion device <NUM>. The controller <NUM> in turn sends signals to the primary propulsion device <NUM> to activate actuators for shift or direction and for engine throttle or motor speed, respectively. As is known, the joystick <NUM> can also be used to input requests for movement to the controller <NUM>, such as when the operator desires more controlled movement of the marine vessel <NUM>, such as for example purely longitudinal movement, purely lateral movement, purely rotational movement, or any combination thereof, as is known in the art.

The trolling motor assembly <NUM> can be controlled by the controller <NUM> as well, in response to inputs to the joystick <NUM>, steering wheel <NUM>, and shift/speed lever <NUM>, as described in <CIT>. Additionally or alternatively, the trolling motor assembly <NUM> can be controlled by its own controller (see <NUM>, <FIG>), such as one located in the head or base of the trolling motor assembly <NUM>. In this way, the trolling motor assembly <NUM> can be operated independently of the inputs to the joystick <NUM>, steering wheel <NUM>, and shift/speed lever <NUM>. Those having ordinary skill in the art would understand that such control could be accomplished via inputs to a user interface on the head or base of the trolling motor assembly <NUM> and/or via inputs to a remote control <NUM> dedicated to controlling the trolling motor assembly <NUM> and/or via inputs to a foot pedal, as will all be described herein below with respect to <FIG>. Further, the marine electronic device <NUM> could also be used to provide inputs to the trolling motor controller <NUM> due to connection between the two provided by the CAN bus <NUM>, as is known.

It should be recognized that other inputs may be incorporated in addition to, or instead of, those described in the above embodiment. For example, inputs may come from other physical devices or from non-human sources, such as from electronic anchoring, waypoint tracking, or heading control systems. Similarly, the control functions described in conjunction with controller <NUM> may be distributed across multiple controllers, such as separate controllers within the propulsion devices <NUM>, <NUM> or located elsewhere on the marine vessel <NUM>.

<FIG> shows a block diagram of an example trolling motor system <NUM> that is part of the marine propulsion system <NUM> associated with the trolling motor assembly <NUM>. As shown, the trolling motor system <NUM> may include a number of different modules or components, each of which may comprise any device or means embodied in either hardware, software, or a combination of hardware and software configured to perform one or more corresponding functions. For example, the trolling motor system <NUM> may include a trolling motor assembly <NUM> (that includes, for example, a main housing <NUM> and a trolling motor housing <NUM>), a user input assembly <NUM> (e.g., a foot pedal assembly), and a remote control <NUM>. While the user input assembly <NUM> and the remote control <NUM> are shown as being outside the trolling motor assembly <NUM>, in some embodiments, one or more of them may be included within the trolling motor assembly <NUM>.

The trolling motor system <NUM> may also include one or more communications modules configured to communicate with one another in any of a number of different manners including, for example, via a network. In this regard, the communication interface (e.g., <NUM>, <NUM>', <NUM>") may include any of a number of different communication backbones or frameworks including, for example, Ethernet, the NMEA <NUM> framework, GPS, cellular, WiFi, Bluetooth, Bluetooth Low Energy, Zigbee, or other suitable networks. The network may also support other data sources, including GPS, autopilot, engine/motor data, compass, radar, etc. Numerous other peripheral, remote devices such as a wired or wireless marine electronic device <NUM> may be connected to the trolling motor system <NUM>.

The trolling motor assembly <NUM> may include a main housing <NUM>, a trolling motor housing <NUM>, and, in some embodiments, a shaft therebetween. Though various modules/systems are shown within one or more of the main housing <NUM> and/or the trolling motor housing <NUM>, various modules/systems may be present outside of the main housing <NUM> or trolling motor housing <NUM>, but still may be a part of the trolling motor assembly <NUM>.

The main housing <NUM> can be the head or the base of the trolling motor assembly <NUM> and may include a processor <NUM>, a sonar signal processor <NUM>, a memory <NUM>, a communication interface <NUM>, a display <NUM>, a user interface <NUM>, a steering assembly <NUM>, and one or more sensors (e.g., location sensor <NUM>, a position/orientation sensor <NUM>, etc.). Together, at least the processor <NUM> and memory <NUM> make up the trolling motor controller <NUM>.

The processor <NUM> and/or the sonar signal processor <NUM> may be any means configured to execute various programmed operations or instructions stored in a memory device (e.g. memory <NUM>) such as a device or circuitry operating in accordance with software or otherwise embodied in hardware or a combination of hardware and software (e.g., a processor operating under software control or the processor embodied as an application specific integrated circuit (ASIC) or field programmable gate array (FPGA) specifically configured to perform the operations described herein, or a combination thereof) thereby configuring the device or circuitry to perform the corresponding functions of the processors <NUM>, <NUM> as described herein.

In this regard, the processor <NUM> may be configured to analyze electrical signals communicated thereto to provide display data to the display <NUM> or other remote display. In some example embodiments, the processor <NUM> or sonar signal processor <NUM> may be configured to receive sonar data indicative of the size, location, shape, etc. of objects detected by a sonar transducer assembly <NUM> located in the trolling motor housing <NUM>. In some embodiments, the processor <NUM> may be configured to implement signal processing or enhancement features to improve the display characteristics or data or images and/or to collect or process additional data, such as time, GPS information, waypoint designations, etc. and/or to filter extraneous data to better analyze the collected data. The processor <NUM> may further implement notices and alarms, such as those determined or adjusted by a user, to reflect depth, presence of fish, proximity of other watercraft, a person overboard event, etc..

The memory <NUM> may be configured to store instructions, computer program code, marine data, such as sonar data, chart data, location data, position/orientation sensor data, and other data associated with the trolling motor system <NUM> in a non-transitory computer readable medium for use by the processor <NUM>.

The communication interface <NUM> may be configured to enable connection to external systems (e.g., an external network <NUM>) and/or other systems, such as the user input assembly <NUM> and remote control <NUM>. In this manner, the processor <NUM> may retrieve stored data from a remote, external server via the external network <NUM> in addition to or as an alternative to the onboard memory <NUM>.

The position/orientation sensor <NUM> may be found in one or more of the main housing <NUM>, the trolling motor housing <NUM> (see position/orientation sensor <NUM>'), steering assembly <NUM>, or remotely. In some embodiments, the position/orientation sensor <NUM> may be configured to determine a direction in which the trolling motor housing <NUM> is facing (e.g., compass heading). In some embodiments, the position/orientation sensor <NUM> may be operably coupled to either the shaft or steering assembly <NUM>, such that the position/orientation sensor <NUM> measures the rotational change in position of the trolling motor housing <NUM> as the trolling motor is turned. The position/orientation sensor <NUM>, <NUM>' may be a magnetic sensor, a mechanical sensor, or the like.

The location sensor <NUM> may be configured to determine the current position and/or location of the main housing <NUM>. For example, the location sensor <NUM> may comprise a GPS device, a bottom contour sounding device, an inertial navigation system, a ring laser gyroscope, or other location detection system.

The steering assembly <NUM> may include a motor or other mechanism configured to engage and rotate the shaft of the trolling motor assembly <NUM>. For example, the motor may rotate to move a belt drive, gear drive, or the like, which rotates the shaft to cause the trolling motor housing <NUM> to be positioned to a desired direction of thrust.

The display <NUM> may be configured to display images and may include or otherwise be in communication with a user interface <NUM> configured to receive input from a user. The display <NUM> may be, for example, a conventional LCD display, an LED display, or the like. In some example embodiments, additional displays may also be included, such as a touch screen display, mobile device, or any other suitable display known in the art upon which images may be displayed. In any of the embodiments, the display <NUM> may be configured to display relevant trolling motor information including, but not limited to, speed data, motor data battery data, current operating mode, autopilot information, or the like.

The user interface <NUM> may include, for example, a keyboard, keypad, function keys, mouse, scrolling device, input/output ports, touch screen, or any other mechanism by which a user may interface with the trolling motor system <NUM>.

The trolling motor housing <NUM> may include a trolling motor <NUM> for powering a propeller coupled thereto, a sonar transducer assembly <NUM>, and one or more other sensors (e.g., position/orientation sensor <NUM>', water temperature sensor, water current sensor, etc.), which may each be controlled by the processor <NUM>.

The user input assembly <NUM> may be any device capable of receiving user input and controlling at least some operations of the trolling motor system <NUM>. For example, the user input assembly <NUM> may be a foot pedal. Depending on the configuration of the trolling motor system <NUM>, the user input assembly <NUM> may include a processor <NUM>', memory <NUM>', communication interface <NUM>', and a deflection sensor <NUM>. The processor <NUM>', memory <NUM>', communication interface <NUM>', and user interface <NUM>' may include features and functions such as described herein with respect to the corresponding module/system in the trolling motor assembly <NUM> (e.g., the processor <NUM>, the memory <NUM>, communication interface <NUM>, and user interface <NUM>). The deflection sensor <NUM> may be any device capable of sensing the position/deflection of a portion of the user input assembly <NUM>, such as the foot pedal of the user input assembly <NUM>. Such deflection may be used to control the rotation of the trolling motor shaft (e.g., the direction/orientation of the propeller).

The remote control <NUM> may be any device capable of receiving user input and controlling at least some operations of the trolling motor system <NUM> remotely. For example, the remote control <NUM> may be a wired or wireless remote control or a remote computing device, such as a dedicated marine electronics device or a personal computing device such as a phone or tablet. Although the remote control <NUM> is shown in <FIG> as being wireless/removable for purposes of carrying out some examples of the method of the present disclosure, it could be wired in other examples (e.g., when fobs are used to detect an overboard event as discussed herein below). Depending on the configuration of the trolling motor system <NUM>, the remote control <NUM> may include a processor <NUM>", memory <NUM>", communication interface <NUM>", display <NUM>", user interface <NUM>", and location sensor <NUM>". The processor <NUM>", memory <NUM>", communication interface <NUM>", display <NUM>", user interface <NUM>", and location sensor <NUM>" may include features and functions such as described herein with respect to the corresponding module/system in the trolling motor assembly <NUM> (e.g., the processor <NUM>, memory <NUM>, display <NUM>, communication interface <NUM>, user interface <NUM>, and location sensor <NUM>) or the user input assembly <NUM> (e.g., the processor <NUM>', memory <NUM>', communication interface <NUM>', and user interface <NUM>').

By way of example, an operator can interact with the user interface <NUM>" and/or display <NUM>" to control the thrust of the trolling motor assembly <NUM>. The remote control <NUM> may be provided with operator-selectable options to move forward, backward, turn left/right, and increase/decrease the speed of or stop the propeller. The remote control <NUM> may also be provided with options to enable one or more of the automatic navigation modes described herein. Inputs to the remote control <NUM> are communicated via communication interfaces <NUM>" and <NUM> to the processor <NUM>, which is configured to carry out the commands by controlling the steering assembly <NUM> and/or trolling motor <NUM>.

The remote control <NUM> also includes an accelerometer <NUM> within its housing. The accelerometer <NUM> is a conventional three-axis accelerometer that can output electrical signals indicating the direction of movement and amount of movement of the accelerometer <NUM> with respect to the mutually perpendicular X-, Y-, and Z-axes. Such a three-axis accelerometer that outputs direction of movement and amount of movement is known in the art. The output of the accelerometer <NUM> can be an analog voltage or digital signal and can have a duty cycle output (ratio of pulse width to period) that is proportional to acceleration. The duty cycle output can be directly measured by the processor <NUM> to determine the noted amount of acceleration and direction of movement with respect to the X-, Y-, and Z-axes. The accelerometer <NUM> is attached to a printed circuit board within the remote control <NUM>. The communication interface <NUM>" is connected to the printed circuit board as well and electrically receives and communicates the outputs of the accelerometer <NUM> to the communication interface <NUM>, which relays the outputs to the processor <NUM>. In some examples, the accelerometer <NUM> is part of a six-axis MEMS motion sensor, which includes a three-axis accelerometer as well as a three-axis gyroscope that measures pitch, roll, and yaw of the remote control <NUM>.

In some examples, any of the user interfaces <NUM>, <NUM>', <NUM>" includes a plurality of user-selectable buttons, softkeys, or menu options that allow the trolling motor assembly <NUM> to operate in an automatic navigation mode. One user-selectable option may, for example, cause the trolling motor assembly <NUM> to maintain the marine vessel <NUM> at a given heading. Another user-selectable option may, for example, cause the trolling motor assembly <NUM> to maintain the marine vessel <NUM> at a given depth. Another user-selectable option may be an "electronic anchor," that causes the trolling motor to maintain the marine vessel <NUM> at a specific location (e.g., by maintaining GPS coordinates). Yet another user-selectable option may cause the marine vessel <NUM> to head to a waypoint or to traverse a route including a series of waypoints. The user-selectable options may actuate the processor <NUM> to automatically control the thrust produced by the trolling motor assembly <NUM> according to the selected option. According to some example embodiments, the processor <NUM> may be configured to determine a destination (e.g., via input by a user) and route for the marine vessel <NUM> and to control the steering assembly <NUM> to steer the trolling motor <NUM> in accordance with the route and destination. The memory <NUM> may store digitized charts and maps to assist with such autopilot navigation or the charts and maps may be accessed from the external network <NUM>. To determine a destination and route for the marine vessel <NUM>, the processor <NUM> may employ the location sensor <NUM> and/or the position/orientation sensor <NUM>. Based on the route, the processor <NUM> may determine that different rates of turn may be needed to efficiently move along the route to the destination. In other examples, the processor <NUM> may use information from the sonar transducer assembly <NUM> and/or one or more maps or charts stored in the memory <NUM> or accessible from the external network <NUM> to actuate the steering assembly <NUM> to steer the trolling motor <NUM> such that the marine vessel <NUM> follows a path that maintains the marine vessel <NUM> at a given water depth.

<FIG> illustrates the portion of the marine propulsion system <NUM> related to the primary propulsion device <NUM>, i.e. the primary propulsion system <NUM>. The steering wheel <NUM>, marine electronic device <NUM>, joystick <NUM>, and shift/speed lever <NUM> were described hereinabove and are in signal communication with the controller <NUM>, which includes the above-noted processing system <NUM> and storage system <NUM>. The controller <NUM> may also receive an input from one or more vessel speed sensors <NUM>. The vessel speed sensor <NUM> may be, for example, a pitot tube sensor 40a, a paddle wheel type sensor 40b, or any other speed sensor appropriate for sensing the actual speed of the marine vessel <NUM>. Alternatively or additionally, the vessel speed may be obtained by taking readings from a GPS device <NUM>, which calculates speed by determining how far the marine vessel <NUM> has traveled in a given amount of time. Similarly, the controller <NUM> may receive input from a location sensor, such as GPS device <NUM>, which continuously tracks and provides global position information describing the current location of the marine vessel <NUM>. The propulsion device <NUM> is provided with an engine/motor speed sensor <NUM>, such as but not limited to a tachometer, which determines a speed of the engine or motor <NUM> in rotations per minute (RPM). The engine/motor speed can be used along with other measured or known values to approximate a vessel speed (i.e., to calculate a pseudo vessel speed). A gear system <NUM> and gear state sensor <NUM> can also be provided for the propulsion device <NUM>. For example, the gear state sensor <NUM> may provide an output indicating whether the gear system <NUM> (which may take any of various forms known in the art, such as a dog clutch) is in a forward gear state, a neutral state, or a reverse gear state. In the example in which the prime mover is a motor, the gear state sensor can be a sensor that determines which direction the propeller shaft is moving, or an algorithm that determines the direction of current provided to the motor. In certain embodiments, the outputs of the gear state sensor <NUM> and/or the engine/motor speed sensor <NUM> may be provided directly to the controller <NUM>. In other embodiments, the gear state and engine/motor speed information may be provided to an intermediary control device, such as an propulsion control module (PCM) <NUM>, which may then make such information available to the controller <NUM>.

Similar to the trolling motor system <NUM> of <FIG>, the primary propulsion system <NUM> is also operable in one or more automatic navigation modes. For example, the controller <NUM> can be enabled in an auto-heading or a waypoint tracking mode, as disclosed in <CIT> or <CIT>. In the auto-heading mode, the marine vessel <NUM> is maintained at a predetermined heading. To initiate auto-heading, for example, the operator of the marine vessel <NUM> could select a numerical heading from a keypad or a touch screen (found for example, on marine electronic device <NUM>) and select the auto-heading feature, for example via the same keypad or touchscreen. Alternatively, the operator could manipulate the steering wheel <NUM> or joystick <NUM> until the marine vessel <NUM> is oriented to a desired heading, and then select the auto-heading feature. The controller <NUM> would then maintain the marine vessel <NUM> at this commanded heading for an extended period of time with little or no operator input required. For example, if wind, waves, or the like push the marine vessel <NUM> off course, the controller <NUM> would determine the corrective action needed to return the marine vessel <NUM> to the commanded heading, and provide steering and thrust commands to the propulsion device <NUM> so as to correct the direction of the marine vessel <NUM> such that it thereafter continues at the commanded heading.

In the waypoint tracking mode, the marine vessel <NUM> is automatically guided to a point (e.g., a global position defined in terms of latitude and longitude) or several points along a track. To initiate waypoint tracking mode, for example, the operator of the marine vessel <NUM> may select a point or track from a chart plotter (one example of the marine electronic device <NUM>) and thereafter select waypoint tracking mode, for example via a keypad or touchscreen. The controller <NUM> then obtains a commanded heading from the autopilot control module (which is programmable code stored in the storage system <NUM> and executed by the processing system <NUM>) according to the information provided by the chart plotter. The controller <NUM> then automatically guides the marine vessel <NUM> to each point along the track (or to the single selected point) by providing steering and thrust commands to the propulsion device <NUM>. If the marine vessel <NUM> veers off course, such as due to the effect of wind, waves, or the like, the controller <NUM> determines the corrective action needed to resume the commanded heading so as to guide the marine vessel <NUM> back to the desired point and/or track. The controller <NUM> provides steering and/or thrust commands to the propulsion device <NUM> to achieve such corrective action.

In some examples, the controller <NUM> is configured to use both the trolling motor assembly <NUM> and the primary propulsion device <NUM> to carry out the automatic navigation modes, as described in <CIT>.

In both the auto-heading and waypoint tracking modes, the controller <NUM> uses a heading feedback signal (indicating an estimate of the heading at which the marine vessel <NUM> is actually being propelled) to determine whether correction needs to be made to the actual heading of the marine vessel <NUM> in order to maintain the commanded heading. The controller <NUM> uses the heading feedback signal to determine how and to what extent the propulsion device <NUM> must be steered (and/or with what thrust) in order to re-orient the marine vessel <NUM> to the commanded heading. Automatic correction of the heading of the marine vessel <NUM> can be achieved according to the principles described in <CIT> and <CIT>. The heading feedback signal can be provided by a compass or an inertial measurement unit (IMU) <NUM> provided in signal communication with the controller <NUM>.

A person overboard detection control module <NUM> is a set of software instructions executable on a processor and configured to determine whether an individual may have fallen overboard and to generate commands in response to such a determination. The controller <NUM> stores and executes the person overboard detection control module <NUM>, including executing logic to determine whether an individual may have fallen overboard and providing control instructions to the primary propulsion device <NUM> and/or trolling motor assembly <NUM> accordingly. In the depicted embodiment, the person overboard detection control module <NUM> is stored on the storage system <NUM> and executable on the processing system <NUM> of the controller <NUM>. In the depicted embodiment, the controller <NUM> communicates with PCM <NUM> of the propulsion device <NUM>. Although not shown herein, the controller <NUM> may also communicate with the controller <NUM> of the trolling motor assembly <NUM>. Thereby, the controller <NUM> can instruct the PCM <NUM> and/or trolling motor controller <NUM> in order to effectuate certain control actions, for example, changing the engine/motor speed and/or gear state of the propulsion device <NUM> and/or <NUM> in response to detecting that an individual may have fallen overboard.

In order to determine if an individual may have fallen overboard, each individual can be provided with a portable device to be worn on or carried by that individual. The portable devices can include an operator fob <NUM> and one or more passenger fobs <NUM>. According to the present disclosure, in examples in which fobs are used, at least the operator is provided with the operator fob <NUM>, for reasons described herein below. The fobs <NUM>, <NUM> are in wireless communication with a communication interface <NUM> that is in communication with the controller <NUM>. The communication interface <NUM> can be a separate transceiver or receiver that communicates with the controller <NUM> or can be a transceiver or receiver built into a housing of the controller <NUM>. The communication interface <NUM> can be part of or separate from the I/O interface <NUM> shown in <FIG>. The wireless fobs <NUM>, <NUM> may be battery-driven, such as containing replaceable or rechargeable batteries. The communication interface <NUM> and wireless fobs <NUM>, <NUM> may communicate by any of various wireless protocols. In certain embodiments, the communication interface <NUM> and wireless fobs <NUM>, <NUM> may be RFID devices. In one embodiment, the wireless fobs <NUM>, <NUM> may contain passive or active RFID tags, and the communication interface may be an active or passive reader, which operate by any of various wireless standards, including but not limited to Bluetooth, Zigbee, or <NUM> WLAN. The fobs <NUM>, <NUM> can each be provided with a three-axis accelerometer or a six-axis MEMS motion sensor, which function in the manner noted herein above with respect to accelerometer <NUM> in remote control <NUM>, thereby providing the controller <NUM> with information related to accelerations of the respective fobs <NUM>, <NUM> about the X-, Y-, and Z-axes. In some instances, the fobs <NUM>, <NUM> may be provided with GPS devices as well.

Returning to <FIG>, the trolling motor system <NUM> may also be configured to determine if a person has fallen overboard. For example, the memory <NUM> may store a person overboard detection control module <NUM>', which is a set of software instructions executable on a processor and configured to determine whether an individual may have fallen overboard and to generate commands in response to such a determination. In the depicted embodiment, the person overboard detection control module <NUM>' is stored in the memory <NUM> and executable on the processor <NUM>, which together constitute at least part of the controller <NUM>. In the depicted embodiment, the controller <NUM> commands the trolling motor <NUM> and the steering assembly <NUM> of the trolling motor assembly <NUM>. Thereby, the controller <NUM> can instruct the trolling motor <NUM> and the steering assembly <NUM> in order to effectuate certain control actions, for example, changing the motor speed and/or direction and/or steering angle in response to detecting that an individual may have fallen overboard. Similar to the embodiment of <FIG>, in one example, the communication interface <NUM>" of the remote control <NUM> may be or comprise a passive or active RFID tag, and the communication interface <NUM> of the trolling motor assembly <NUM> may be or comprise an active or passive reader, which operate by any of various wireless standards as noted hereinabove.

Those having ordinary skill in the art will understand that the remote control <NUM> for the trolling motor system <NUM> is typically carried by the operator as the operator moves around the marine vessel <NUM>. Sometimes, the remote control <NUM> may be provided with a lanyard that the operator can wear around the operator's neck while the remote control <NUM> is not in use, such as after the operator has enabled one of the above-noted automatic navigation modes. Further, one having ordinary skill in the art is also familiar with the types of fobs <NUM>, <NUM> that an individual (whether an operator or passenger) can be provided with, such as a device on a lanyard to be worn about the neck, a device with a strap to be worn about the wrist or ankle, a device to be clipped onto the individual's clothes or life jacket, or any other device that can be held or worn by the individual. In this regard, the remote control <NUM> and the fobs <NUM>, <NUM> (and the fob <NUM> and clip <NUM> described herein below with respect to <FIG>) constitute portable devices for purposes of the present disclosure. Further, one having ordinary skill in the art will appreciate that although the primary propulsion system <NUM> is shown as being in communication with the fobs <NUM>, <NUM>, the trolling motor system <NUM> could also be in communication with the same fobs <NUM>, <NUM> or dedicated fobs, such that the trolling motor assembly's communication interface <NUM> is configured for signal communication with any non-remote-control operator or passenger portable devices on the marine vessel <NUM>. Further, it is possible that the primary propulsion system <NUM> could be provided with a portable device that is also a remote control device, such as a joystick or keypad that is movable about the marine vessel <NUM> and communicates with the controller <NUM> to command the propulsion device <NUM> to produce thrust, likely at low speeds only.

Thus, the present disclosure is of a system <NUM>, <NUM> for a marine vessel <NUM> propelled by a propulsion device <NUM>, <NUM>, the system <NUM>, <NUM> including a controller <NUM>, <NUM> operable in an automatic navigation mode in which the controller <NUM>, <NUM> automatically controls a thrust of the propulsion device <NUM>, <NUM> to propel the marine vessel <NUM> through a body of water. As noted hereinabove, the automatic propulsion mode can be a waypoint tracking mode, an auto-heading mode, a depth tracking mode, a head-to-waypoint mode, or any other mode in which the marine vessel <NUM> is automatically propelled without operator intervention other than initial selection of such a mode. The system <NUM>, <NUM> also includes a portable device <NUM>, <NUM>, <NUM> configured to be carried on an individual on the marine vessel <NUM>, such as carried by or worn by the individual as described hereinabove. In one example, the portable device is a fob <NUM>, <NUM> that is not provided with remote control functionality. In another example, the portable device is a remote control <NUM> configured to allow the individual to control the thrust of the propulsion device.

According to the present disclosure, the controller <NUM>, <NUM> enables a person overboard detection algorithm in response to enablement of an automatic navigation mode. The person overboard detection algorithm is stored in the person overboard detection control modules <NUM>, <NUM>' described hereinabove. For example, in response to receiving an input command via the remote control <NUM>, the user input assembly <NUM>, or the user interface <NUM> that enables one of the automatic navigation modes, the trolling motor controller <NUM> will set a flag to enable the person overboard detection algorithm. Similarly, in response to receiving an input command via the marine electronic device <NUM>, the joystick <NUM>, or other remote control device that enables one of the automatic navigation modes, the primary propulsion device's controller <NUM> will set a flag to enable the person overboard detection algorithm. The flag in both instances remains set until the automatic navigation mode is canceled or otherwise disabled. Note that the flag may be set in response to a mere input to operate in the automatic navigation mode, or may be set in response to the controller <NUM>, <NUM> actually beginning to operate the propulsion device <NUM>, <NUM> in the automatic navigation mode. In the latter instance, there may be times when a user input does not result in enablement of the automatic navigation mode, such as for example if the marine vessel <NUM> is travelling too fast as determined by the speed sensor <NUM> or there is no signal from the GPS device <NUM> or location sensor <NUM>.

According to the present disclosure, and as will be described further below, the person overboard detection algorithm disables the automatic navigation mode in response to detecting a given status of the portable device <NUM>, <NUM>, <NUM>. The present inventors have realized, through research and development, that automatically disabling the previously enabled automatic navigation mode in the event of an individual falling overboard is desirable because it prevents the marine vessel <NUM> from traveling too far away from where the individual went overboard. Other known person-overboard algorithms are intended to take into account vessel speed such as in order to prevent the marine vessel from jerking to a stop in response to a person falling overboard. However, typically, when a marine vessel is operating in an automatic navigation mode, especially when under the thrust of the trolling motor assembly <NUM> only, the marine vessel <NUM> is not traveling fast enough that promptly disabling the automatic navigation mode will cause such a drastic reduction in speed. Thus, the present inventors have also developed a system and method that allow for more prompt detection of a person overboard event, such that the automatic navigation mode can be disabled as soon as possible, thereby increasing the likelihood that the marine vessel <NUM> will not have traveled far from the overboard person in the meanwhile.

The given status of the portable device generally relates to the distance of the portable device <NUM>, <NUM>, <NUM> from the controller <NUM>, <NUM> with which it is in communication. For example, this distance can be measured by signal strength or by comparison of GPS locations. In another example, the distance of the portable device <NUM>, <NUM>, <NUM> from the controller <NUM>, <NUM> is related to whether the portable device <NUM>, <NUM>, <NUM> remains physically connected to a switch in signal communication with the controller <NUM>, <NUM>. Each of these examples will be described hereinbelow.

In one example, the system <NUM>, <NUM> includes a receiver (e.g., one example of the communication interface <NUM>, <NUM>) in signal communication with the controller <NUM>, <NUM>. In one example, the receiver may be a transceiver. In one particular example, the receiver may be an active or passive RFID reader. In such an example, the portable device <NUM>, <NUM>, <NUM> comprises a transmitter (e.g., one example of the communication interface <NUM>"). In one example, the transmitter is a transceiver. In one particular example, the transmitter is an active or passive RFID tag. In such an example, the given status of the portable device <NUM>, <NUM>, <NUM> relates to a signal strength of the transmitter (i.e., RFID tag) as received by the receiver (e.g., RFID reader). For simplicity's sake, the portable device <NUM>, <NUM>, <NUM> will hereinafter be referred to as the transmitter and the communication interface <NUM>, <NUM> will hereinafter be referred to as the receiver when referring to signal strength. Signal strength is the power level being received by the receiver from the transmitter and is determined by the transmission power, the distance between the transmitter and the receiver, and the intermediary environment. Those having ordinary skill in the art are familiar with a received signal strength indicator (RSSI) on wireless devices and how it provides an indication of received signal strength (RSS). The RSS can be used directly to determine whether an individual holding or wearing the portable device <NUM>, <NUM>, <NUM> may have fallen overboard. For example, knowing the maximum distance from the receiver to the edges of the marine vessel <NUM> can allow one to determine the approximate RSS at the receiver were the transmitter to be anywhere on the marine vessel <NUM>. An RSS below this threshold may indicate that the transmitter has fallen overboard. Further, the user may be guided through a calibration/setup procedure, wherein the user stands at various locations on the marine vessel <NUM> and allows the receiver to measure the signal strength of the transmitter at each of those locations. The lowest signal strength can be set as the threshold below which a transmitter is deemed to have fallen overboard.

Not only can the RSS itself be used to determine if the transmitter (and thus likely the individual holding or wearing it) has fallen overboard, but also the change in RSS over time can be used for the same purposes. In one example, the person overboard detection algorithm disables the automatic navigation mode in response to detecting an abrupt change in the received signal strength of the transmitter. Such an abrupt change (calculated as a derivative of the RSS), if above a given threshold, may allow for detection of a person overboard event more promptly than simply using the RSS. For example, if the derivative of the RSS is above a threshold, it is unlikely a person has jumped from one spot on the marine vessel <NUM> to another, and more likely that they have fallen overboard. The abrupt change in RSS may be due not only to the person falling overboard and the marine vessel <NUM> continuing to move away from them under automatic control, but may also be due to the transmitter temporarily being underwater as the person is first submerged or due to the signal from the transmitter reflecting, refracting, or diffracting differently due to the hull now being at least partially between the transmitter and the receiver. Thus, smaller changes in RSS are able to be detected and used to determine if a person has fallen overboard, allowing for more prompt subsequent action.

In some examples, GPS position is used to determine if the portable device <NUM>, <NUM>, <NUM> is far enough from the marine vessel <NUM> that a person holding or wearing the portable device <NUM>, <NUM>, <NUM> has likely fallen overboard. For example, the controller <NUM> or <NUM> can compare the GPS position of the portable device <NUM> or <NUM>, <NUM> to the GPS position of the GPS device <NUM> or the location sensor <NUM>. If the GPS positions are greater than a given threshold distance from one another, the controller <NUM> or <NUM> determines that a person has likely fallen overboard. However, because GPS is typically accurate to within a couple meters, this method may work better on larger marine vessels and may not be as prompt at detecting a person overboard event as the method of using RSS or the derivative of RSS.

In either the instance of using RSS or its derivative or in the instance of using GPS position to determine if a person may have fallen overboard, the acceleration of the portable device <NUM>, <NUM>, <NUM> may also be used to provide information related to the given status of the portable device <NUM>, <NUM>, <NUM>. As noted hereinabove, the portable device <NUM>, <NUM>, <NUM> may also include an accelerometer (e.g., accelerometer <NUM>) and the person overboard detection algorithm disables the automatic navigation mode in response to an abrupt change in acceleration of the portable device <NUM>, <NUM>, <NUM> as determined by the accelerometer. It may be empirically determined what pattern of lateral and/or vertical movement precedes a person falling overboard, and the controller <NUM>, <NUM> may compare this empirical data to a signal from the accelerometer to determine whether it is likely a person has fallen overboard, or whether instead they have simply dropped their portable device <NUM>, <NUM>, <NUM> on the marine vessel <NUM> or into the water. Further, instead of being used as a secondary source of information, in addition to the RSS or GPS position, accelerometer data alone can be used as the criteria to determine whether it is likely a person has fallen overboard.

In some examples, RSS or its derivative alone is used to determine if a person has fallen overboard. In other examples, comparison of the GPS position of the portable device with the GPS position of the marine vessel alone is used to determine if a person has fallen overboard. In other examples, accelerometer data alone can be used to determine if a person has fallen overboard. Further, any combination of two of the above-noted sources of information or all three sources of information can be used to determine if a person has fallen overboard.

Further, in some examples, the controller <NUM> is configured to disable the automatic navigation mode in response to information from only the operator fob <NUM> or the remote control <NUM>, but not in response to information from a passenger fob <NUM>. This prevents the marine vessel from automatically navigating away from the operator if the operator is the person who fell overboard. As long as the operator remains on the marine vessel, they are able to cancel the automatic navigation mode if necessary in response to a passenger leaving the marine vessel. For example, it may be that a passenger purposefully jumped off the marine vessel and simply forgot to remove their fob, and under such circumstances, it may not be necessary to discontinue the automatic navigation mode.

In one example, besides disabling the automatic navigation mode in response to detecting the given status of the portable device <NUM>, <NUM>, <NUM>, the person overboard detection algorithm controls the propulsion device <NUM>, <NUM> to stop producing thrust in response to detecting the given status of the portable device <NUM>, <NUM>, <NUM>. For example, the controller <NUM> may stop the trolling motor <NUM>, or the controller <NUM> may place the gear system <NUM> in neutral. This not only lessens the likelihood that the marine vessel <NUM> will travel further from the person than it already has, but also allows the overboard person to approach the marine vessel <NUM> without fear of contact with a spinning propulsor. In another example, if the location sensor <NUM> and/or position/ orientation sensor <NUM> (or the GPS device <NUM> or IMU <NUM>) indicate that the marine vessel <NUM> is drifting or being blown from the location where the automatic navigation mode was initially disabled, the controller <NUM> (or <NUM>) can enable a spot-lock or station-keeping feature of the propulsion device <NUM> (or <NUM>) in order to maintain the marine vessel <NUM> close to where the person likely went overboard.

In another example, the person overboard detection algorithm is configured to determine if the marine vessel <NUM> is within a given range of the person who fell overboard. This may be done by comparing a location of the portable device <NUM>, <NUM>, <NUM> as determined by a location sensor therein (e.g., location sensor <NUM>' in remote control <NUM>) with a location of the marine vessel <NUM> as determined by a location sensor thereupon (e.g. GPS device <NUM> or location sensor <NUM>). This may additionally or alternatively be done by determining whether the communication interface (e.g., RFID chip or RF transceiver) of the portable device <NUM>, <NUM>, <NUM> is within signal range of the communication interface <NUM>, <NUM> on the marine vessel <NUM>. If the marine vessel <NUM> is not within range of the person who fell overboard, the person overboard detection algorithm controls the propulsion device <NUM>, <NUM> to cause the marine vessel <NUM> to backtrack along an immediately prior course of the marine vessel <NUM> in response to detecting the given status of the portable device. For example, if the marine vessel <NUM> had been in waypoint tracking mode, the controller <NUM> or <NUM> commands the propulsion device <NUM> or <NUM> to propel the marine vessel <NUM> back to the immediately prior waypoint. If the marine vessel <NUM> had been in auto-heading mode, the controller <NUM> or <NUM> commands the propulsion device <NUM> or <NUM> to begin heading in the opposite compass heading. In another example, instead of backtracking exactly along the prior course, the controller <NUM> or <NUM> is configured to backtrack to the position of the overboard person, as determined by the GPS position of the portable device <NUM>, <NUM>, <NUM> and/or by sonar or other proximity sensor data. The controller <NUM>, <NUM> can set the location of the person as a point of interest and can cause the marine vessel <NUM> to circle that point at a predetermined radius. In any of the above examples of backtracking, the controller <NUM>, <NUM> may be configured to guide the marine vessel <NUM> to a standoff distance from the overboard person and to electronically anchor there. In other examples, the controller <NUM>, <NUM> can take into account any current in the water, as determined by a current sensor, and can navigate downstream of where the person went overboard, as they have likely drifted downstream.

It may be that while the marine vessel <NUM> is backtracking along its immediately prior course, or in the event the operator is manually directing the marine vessel <NUM> back to the person who fell overboard, that it would be desirable to reduce the speed of the marine vessel <NUM> as it nears the overboard person. This can prevent overshoot of the person as well as make them feel more confident the marine vessel <NUM> will not contact them. Thus, in some examples, the person overboard detection algorithm controls the propulsion device <NUM> or <NUM> to reduce the thrust thereof in response to determining that the marine vessel <NUM> is within a given range of the portable device <NUM>, <NUM>, <NUM> subsequent to having been outside the given range of the portable device <NUM>, <NUM>, <NUM>. Again, whether the portable device <NUM>, <NUM>, <NUM> is within or out of range of the marine vessel <NUM> can be determined by GPS position, RSS, or the derivative of RSS as noted hereinabove. In another example, a proximity sensor, such as the sonar transducer assembly <NUM> on the trolling motor housing <NUM>, can provide information to the controller <NUM> or <NUM> that indicates the person is within range.

<FIG> illustrates another system <NUM> for detecting a given status of a portable device (such as fob <NUM>) to determine if a person may have fallen overboard such that the automatic navigation mode should be disabled. In this example, the person overboard detection algorithm may be carried out by a dedicated controller <NUM>. In the depicted embodiment, the person overboard detection module <NUM> receives input from the communication interface <NUM> to determine whether to disable the automatic navigation mode. For example, if the fob <NUM> is no longer detected within range of the communication interface <NUM>, then the controller <NUM> may be controlled to disable the automatic navigation mode and to cause the propulsion device <NUM>, <NUM> to stop producing thrust or to propel the marine vessel <NUM> such that it backtracks along its immediately prior course. The controller <NUM> does this by communicating via a communication interface <NUM> with a communication interface <NUM> of the propulsion device <NUM>, <NUM>. In one example, the communication is wireless, as shown here, and can be radio frequency communication. In another example, the communication is wired, such as if the controller <NUM> is plugged into the CAN bus on the marine vessel <NUM> to which the propulsion device <NUM>, <NUM> is also connected. The communication interface <NUM> communicates information from the controller <NUM> to the controller of the propulsion device <NUM>, <NUM>, which may be its own internal controller <NUM> or <NUM>, respectively. The controller <NUM> or <NUM> then controls the engine or motor <NUM>, <NUM> according to the instructions stored in the person overboard detection module <NUM>. The person overboard detection module <NUM> operates in the same or similar way to the person overboard detection control module <NUM>, <NUM>' described hereinabove, as do the other components described sharing the same name (i.e., the communication interfaces <NUM>, <NUM> can be similar to communication interfaces <NUM>, <NUM>; the fob <NUM> can be similar to the fobs <NUM>, <NUM>; etc.).

<FIG> shows an alternative option in phantom in which the portable device is a clip <NUM> that is physically connected to the controller <NUM>. More specifically, the clip <NUM> is directly connected to a switch <NUM> in signal communication with the controller <NUM>. In this example, the switch <NUM> is directly electrically connected to the controller <NUM>, such that removal of the clip <NUM> from the switch <NUM> is directly detected by the controller <NUM> by the opening or closing of an electrical circuit. In this way, the clip <NUM> and switch <NUM> act like a safety lanyard that traditionally has been used to cut power to the propulsion device <NUM>, <NUM> when the clip <NUM> is removed from the switch <NUM> due to the wearer moving too far from the switch <NUM> and pulling on the lanyard <NUM> attached to the clip <NUM>. In this example, also, the person overboard detection algorithm stored on the person overboard detection module <NUM> disables the automatic navigation mode in response to detecting a given status of the portable device (e.g., clip <NUM>). Specifically, the given status of the portable device is that the portable device is not physically connected to a switch <NUM> in signal communication with the controller <NUM>.

In one example, the switch <NUM> is movable onboard the marine vessel <NUM> while still maintaining signal communication with the controller <NUM>. In one particular example, the entire controller <NUM> and switch <NUM> connected thereto are movable about the marine vessel <NUM>. In one example, the controller <NUM> is located in a housing that slides on a rail extending fore and aft along the side of the marine vessel <NUM>. In another example, the controller <NUM> is in a housing that is free to move anywhere on the marine vessel <NUM>. A movable controller may allow the user to move about the marine vessel <NUM> while also using the physically connected lanyard <NUM> and clip <NUM>. It may also allow the user to move the location of the receiver (i.e., communication interface <NUM>) at which signal strength is determined in the event that the wireless fob <NUM> is used. If so configured, the controller <NUM> may communicate wirelessly with the propulsion device <NUM>, <NUM> as long as within range. Alternatively, the controller <NUM> can be plugged into the CAN backbone at one or more access points on the marine vessel <NUM>, which eliminates the need for a separate battery for the controller <NUM>. Note that the concept of having a lanyard <NUM> and clip <NUM> that are physically connected to a switch in signal communication with a controller may also be implemented with a non-dedicated controller, such as the controller <NUM> (or PCM <NUM>) or trolling motor controller <NUM>. However, the ability to move a dedicated controller <NUM> about the marine vessel <NUM> may be particularly helpful for a system and method that are intended to apply person overboard detection algorithms to operation of a marine propulsion system <NUM>, <NUM>, <NUM> in an automatic navigation mode, during which the operator may wish to leave the immediate vicinity of the propulsion device <NUM>, <NUM>.

<FIG> illustrates a method for controlling a propulsion device <NUM>, <NUM> on a marine vessel <NUM>. The method begins at <NUM> and comprises enabling an automatic navigation mode in which a thrust of the propulsion device <NUM>, <NUM> is controlled automatically to propel the marine vessel <NUM> through a body of water. In response to enablement of the automatic navigation mode ("yes" at <NUM>) the method includes enabling a person overboard detection algorithm, as shown at <NUM>. The method <NUM> includes disabling the automatic navigation mode in response to the person overboard detection algorithm determining that an individual on the marine vessel <NUM> may have fallen overboard, as shown at <NUM>. Determining that the individual on the marine vessel <NUM> may have fallen overboard includes detecting a given status of a portable device <NUM>, <NUM>, <NUM>, <NUM>, <NUM> configured to be carried on the individual and in signal communication with a controller <NUM>, <NUM>, <NUM> of the propulsion device <NUM>, <NUM>.

In some particular examples, the portable device <NUM>, <NUM>, <NUM>, <NUM> comprises a transmitter and the given status of the portable device <NUM>, <NUM>, <NUM>, <NUM> relates to a signal strength of the transmitter as received by a receiver in signal communication with the controller <NUM>, <NUM>, <NUM>. For example, the method includes disabling the automatic navigation mode in response to detecting an abrupt change in the received signal strength of the transmitter (i.e., the change in signal strength is greater than a threshold, as shown at <NUM>). The method <NUM> may further include disabling the automatic navigation mode in response to an abrupt change in acceleration of the portable device <NUM>, <NUM>, <NUM>, <NUM> as determined by an accelerometer in the portable device (i.e., the change in acceleration is greater than a threshold, as shown at <NUM>). In the example depicted here, the change in signal strength must be greater than a predetermined threshold before the change in acceleration of the portable device is taken into account. Further, the change in acceleration of the portable device must also be greater than a given threshold before the automatic navigation mode will be disabled at <NUM>. However, in other examples, the change in acceleration may be a first determination and the change in signal strength may be a second determination. In still other examples, only the change in signal strength or the change in acceleration is taken into account to determine whether to disable the automatic navigation mode. In still other examples, other information is taken into account to determine if the person went overboard, such as if the portable device <NUM>, <NUM>, <NUM>, <NUM>, <NUM> is provided with a water sensor, and the fact that the personal device is submerged in water can be communicated to the controller <NUM>, <NUM>, <NUM>. In one example, if certain information is available that suggests a person may have fallen overboard, but not all required information, the portable device or the controller can be configured to emit an alert, such as a sound or vibration. For example, if the accelerometer in the portable device indicates that a pattern similar to one known to represent an overboard event has been sensed, but the RSS has not changed, the portable device may emit a beep to let the user know that whatever action they are engaging in could result in falsely triggering the person overboard routine.

In other examples, different determinations may be made between steps <NUM> and <NUM>. For example, the given status of the portable device may be that the portable device (e.g., clip <NUM>) is not physically connected to a switch <NUM> in signal communication with the controller <NUM>. In such an example, the switch <NUM> may be movable onboard the marine vessel <NUM> while still maintaining signal communication with the controller <NUM>.

After step <NUM>, a determination is made at <NUM> as to whether the portable device <NUM>, <NUM>, <NUM>, <NUM> is out of a predetermined range, as determined by lack of an RF signal, weak signal strength, or GPS position. If "yes" at <NUM>, the method <NUM> includes controlling the propulsion device <NUM>, <NUM> to cause the marine vessel <NUM> to backtrack along an immediately prior course of the marine vessel <NUM>, as shown at <NUM>, in response to determining that the individual on the marine vessel may <NUM> have fallen overboard (as previously determined at <NUM> and/or <NUM>). Further, in response to determining at <NUM> that the marine vessel <NUM> is within the given range of the individual subsequent to having been outside the given range of the individual (as previously determined at <NUM>), the method includes reducing the thrust of the propulsion device <NUM>, <NUM>, as shown at <NUM>.

If "no" at <NUM> (i.e., the portable device is within the predetermined range), or after the thrust of the propulsion device has been reduced at <NUM>, the method <NUM> includes discontinuing thrust production by the propulsion device, as shown at <NUM>, in response to determining that the individual on the marine vessel may have fallen overboard (as previously determined at <NUM> and/or <NUM>). If <NUM> follows <NUM>, the stopping of thrust production could be done at a predetermined time period after the thrust was reduced, in response to the portable device or individual being detected within an even closer predetermined range (as determined by RSS, GPS position, and/or proximity sensors), or in response to operator input. If <NUM> immediately follows <NUM>, discontinuing thrust production may automatically follow a determination that the portable device is within range, or may be in response to operator input.

In each of the above examples, the person overboard detection module can be disabled manually, such as if a person would like the marine vessel <NUM> to operate in an automatic navigation mode, but to ignore any information that might signal a person overboard event. The user may use the marine electronic device <NUM> or user interface <NUM>, <NUM>', <NUM>" to enter such a disabling command. The user may use the same device to re-enable the person overboard detection module, or the person overboard detection module may be automatically re-enabled after the automatic navigation mode is disabled and then re-enabled.

Typically, if a person is operating the primary propulsion device <NUM>, they are not also operating the trolling motor assembly <NUM> at the same time, and vice versa. Thus, the controllers <NUM>, <NUM> can be configured to recognize the same fob <NUM>, <NUM>, <NUM> or clip <NUM> for carrying out the person overboard detection algorithm in order to control the propulsion device <NUM> if it is running or in order to control the propulsion device <NUM> if it is running. In the event that both propulsion devices <NUM>, <NUM> are running, a single person overboard event, whether it be triggered based on the status of the remote control <NUM>, fobs <NUM>, <NUM>, <NUM>, or clip <NUM>, will result in action being taken with respect to both propulsion devices <NUM>, <NUM>.

Claim 1:
A method for controlling a propulsion device (<NUM>, <NUM>) on a marine vessel (<NUM>), the method comprising:
enabling an automatic navigation mode in which a thrust of the propulsion device (<NUM>, <NUM>) is controlled automatically to propel the marine vessel (<NUM>) through a body of water, and;
enabling a person overboard detection algorithm in response to enablement of the automatic navigation mode;
wherein the person overboard detection algorithm comprises disabling the automatic navigation mode in response to the person overboard detection algorithm determining that an individual on the marine vessel (<NUM>) may have fallen overboard.