System for controlling position and speed of a marine vessel

A system and non-transient computer readable medium for executing a method for controlling position and speed of a marine vessel propelled by a marine propulsion device along a route including a plurality of waypoints are disclosed. An input source provides the plurality of waypoints to a controller, each individual waypoint being associated with a respective operator-selected desired speed of the marine propulsion device. A position determination device determines an actual geographical location of the vessel, and a speed sensor determines an actual speed of the marine propulsion device. The controller receives a given waypoint and its respective desired speed from the input source, the actual geographical location from the position determination device, and the actual speed from the speed sensor. The controller compares these values and outputs commands to propel the marine vessel to the given waypoint and concurrently to operate the marine propulsion device at the respective desired speed.

FIELD

The present disclosure relates to systems, methods, and methods that can be carried out by a processor for controlling position and speed of marine vessels propelled by marine propulsion devices.

BACKGROUND

The below U.S. patents and U.S. patent applications are hereby incorporated herein by reference.

U.S. Pat. No. 6,273,771 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.

U.S. Pat. No. 7,727,036 discloses a system and method for controlling movement of a marine vessel. An operator controllable device outputs a signal that is representative of an operator-desired rate of position change of the vessel about or along an axis. A sensor outputs a signal that is representative of a sensed actual rate of position change of the vessel about or along the axis. A rate of position change controller outputs a rate of position change command based upon the difference between the desired rate of position change and the sensed rate of position change. A vessel coordination controller controls movement of the vessel based upon the rate of position change command.

Unpublished U.S. patent application Ser. No. 14/200,831, filed on Mar. 7, 2014, discloses a method for determining a heading value of a marine vessel that includes determining a first estimate of a direction of the marine vessel based on information from a first source and determining a second estimate of a direction of the marine vessel based on information from a second source. The method includes inputting the first estimate and the second estimate to a control circuit, which scales each of the first estimate and the second estimate and adds the scaled estimates together so as to determine the heading value. A system for determining a heading value of a marine vessel is also disclosed.

SUMMARY

In one example of the present disclosure, a system for controlling position and speed of a marine vessel propelled by a marine propulsion device along a route comprising a plurality of waypoints is described. A controller is provided in signal communication with the marine propulsion device. An input source provides the plurality of waypoints to the controller, each individual waypoint in the plurality of waypoints being associated with a respective operator-selected desired speed of the marine propulsion device. A position determination device determines an actual geographic location of the marine vessel. A speed sensor determines an actual speed of the marine propulsion device. The controller receives a given waypoint and its respective desired speed from the user interface, the actual geographical location from the position determination device, and the actual speed from the speed sensor. The controller compares the actual geographical location to the given waypoint and the actual speed to the respective desired speed, and outputs commands to propel the marine vessel to the given waypoint and concurrently to operate the marine propulsion device at the respective desired speed.

According to another example of the present disclosure, a non-transient computer readable medium programmed with computer readable code that upon execution by a processor causes the processor to execute a method for controlling position and speed of a marine vessel propelled by a marine propulsion device along a route comprising a plurality of waypoints is disclosed. The method includes accepting the plurality of waypoints from an input source, each individual waypoint in the plurality of waypoints being associated with a respective operator-selected desired speed of the marine propulsion device. The method also includes sending, the plurality of waypoints and the respective desired speeds to a marine propulsion system controller, which thereafter outputs commands to propel the marine vessel to the given waypoint and concurrently to operate the marine propulsion device at the respective desired speed.

DETAILED DESCRIPTION

In the present description, certain terms have been used for brevity, clarity and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed.

FIG. 1schematically depicts a marine vessel12including two marine propulsion devices14a,14b, although fewer or more propulsion devices could be provided. The propulsion devices14a,14bcan be any type of marine propulsion device, such as for example, pod drives, sterndrives, outboards, or jet drives. The propulsion devices14a,14bare communicatively connected to a controller34, such as for example an electronic control unit (ECU). The propulsion devices14a,14bmay alternatively have their own engine control units, which in turn would be connected to the controller34, which in this case could be located at the helm of the marine vessel12. In the example shown herein, however, only one controller34is shown for simplicity, and the controller34sends signals to control the magnitude of thrust produced by the propulsion devices14a,14bin order to propel the marine vessel12at a desired speed, as will be described farther herein below. The position of the marine vessel12can be controlled either by positioning the propulsion device itself (such as with an outboard motor or a sterndrive) or by positioning a rudder of the marine vessel12to change the direction of the marine vessel12. The precise propulsion device and apparatus by which the marine vessel12can change its direction are not limiting on the scope of the present disclosure. For example, although the propulsion device14shown inFIG. 2is powered by an engine16, the propulsion device14could instead be propelled by an electric motor. For purposes of simplicity, the controller34will be described as controlling the direction and magnitude of thrust of the propulsion devices14a,14b, although it should be understood that the controller34could alternatively control the position of a rudder, reversing bucket, trim tab, or the like in order to control the direction of the marine vessel12.

Returning toFIG. 1, the controller34may be communicatively connected to an autopilot system60, which provides inputs to the controller34to control the direction and magnitude of thrust of the propulsion devices14a,14bwith little or no continual input required from the operator of the marine vessel12. For example, the controller34may also be communicatively connected to an input source19, such as for example a chart plotter, which may provide a series of waypoints to which the marine vessel12is to be guided while under the control of the autopilot system60. Alternatively, the autopilot system60may allow an operator of the marine vessel12to select a single waypoint to which the marine vessel12is to be guided, such as by way of the input source19. Besides being a chart plotter, the input source19could be a different device communicating with the controller34via a network connection, a drive or other storage device communicating with the controller34via a USB or similar port, a smart phone or tablet, a PDA, a gauge, a keyboard, a mouse, a computer-readable disc, or any number of other input devices and/or peripherally connectable devices suitable for entering or uploading information to the controller34.

The controller34may also be communicatively connected to a compass80, an inertial measurement unit (IMU)82, a GPS receiver29, and/or a vessel speed sensor30. The compass80can be, for example, a solid state compass or a flux gate compass, although a gyroscope could also be used. The GPS receiver29may provide the location, speed, and direction of the marine vessel12, and in one example can be provided by Mercury Marine of Fond du Lac, Wis., part number 8M0046321. The IMU82can also be provided by Mercury Marine of Fond du Lac, Wis., part number 79-8M0048162. The IMU82may have a solid state, rate gyro electronic compass that detects the direction of the earth's magnetic field using solid state magnetometers and indicates the vessel heading relative to magnetic north. Additionally, solid state accelerometers and angular rate sensors in the IMU82may be provided to sense the vessel's attitude and rate of turn.

The controller34may have a memory and a programmable processor, as will be described further herein below with respect toFIG. 3. As is conventional, the processor can be communicatively connected to a computer readable medium that includes volatile or non-volatile memory upon which computer readable code (software) is stored. The processor can access the computer readable code on the computer readable medium, and upon executing the code can send signals to carry out functions according to the methods described herein below. Execution of the code allows the controller34to control a series of actuators associated with the propulsion devices14a,14b, which actuators provide the above-mentioned variance to the direction and magnitude of thrust. Such actuators include, but are not limited to, a throttle valve, a steering actuator, a trim actuator, and a transmission associated with the propulsion devices14a,14b.

Each of the devices, modules, and sensors can be communicatively connected to the controller34via one or more controller area network (CAN) buses, such as for example as described in U.S. Pat. No. 6,273,771, which was incorporated by reference hereinabove. It should be understood that the connections shown inFIG. 1are not the only possible connections between the devices, modules, and sensors, and that the wiring shown therein is merely exemplary and schematic. Fewer or more connections could be provided. It should also be understood that the devices, modules, and sensors could alternatively communicate wirelessly with one another and/or with the controller34.

According to known autopilot functions, an operator of the marine vessel12may choose to engage in waypoint tracking, during, which the marine vessel12is 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 vessel12may select a point or track (route) using the input source19(such as a chart plotter), and then select waypoint tracking mode from the autopilot system60, for example via a keypad or touchscreen. Alternatively, the operator can both choose a route and select the waypoint tracking mode via the input source19. The controller34then obtains a first commanded heading from the autopilot system60(which can be separate from or integrated with the controller34) according to the information provided by the input source19, which first commanded heading, is intended to steer the marine vessel12toward the first waypoint in the route. Once the first waypoint is reached, the autopilot system60determines a second heading value required to travel to the second waypoint and the controller34commands the propulsion devices14a,141to propel the vessel at the second heading. The controller34thus automatically guides the marine vessel12to each waypoint along the route (or to a single selected point) by providing steering and thrust commands to the propulsion devices14a,14b. If the marine vessel12veers off course as determined by the sensors mentioned above, such as due to the effect of wind, waves, or the like, the controller34determines the corrective action needed to resume the commanded heading so as to guide the marine vessel12back to the waypoint and/or route. The controller34provides steering and/or thrust commands to the propulsion devices14a,14bto achieve such corrective action.

In the waypoint tracking mode, the controller34uses a heading signal (indicating an estimate of the heading at which the marine vessel12is actually being propelled) to determine whether correction needs to be made to the actual heading of the marine vessel12in order to maintain the commanded heading to the next waypoint. The controller34uses the heading signal to determine how and to what extent the propulsion devices14a,14hmust be steered (and/or with what thrust) in order to re-orient the marine vessel12to the commanded heading. For example, if the autopilot system60has commanded a heading of 350 degrees in order to reach the next waypoint in a mute, but external forces have caused the marine vessel12to orient itself to a heading of 345 degrees, the controller34will use a heading signal of 345 degrees to perform calculations to determine to what extent the propulsion devices14a,14bmust be steered (and/or with what thrust) in order to re-orient the marine vessel12to a heading of 350 degrees. Such automatic correction of the heading the marine vessel12can be achieved according to the principles described in U.S. Pat. No. 7,267,068; U.S. Pat. No. 7,305,928; and U.S. Pat. No. 9,039,468, the disclosures of which are hereby incorporated by reference in their entirety.

Many are familiar with the capability of an input source19such as a chart plotter or similar type of user interface or input device to chart, save, and recall a route for a marine vessel to follow automatically. For instance, numerous waypoints defined by geographical coordinates in latitude and longitude can be input to a user input device, and connected such that they form a route for the marine vessel to follow. The waypoints can be input by the operator manually and one at a time, can be obtained in a batch from a disk or downloaded from the internet, or can be input in any number of other ways known to those having ordinary skill in the art. After the waypoints are input and stored as a route, a user can select a waypoint tracking function from the input device or from the autopilot system that allows the user to command the marine vessel to automatically travel to each of the waypoints. Each waypoint's coordinates are sent to the autopilot system60and/or controller34in turn, and the direction and magnitude of thrust of the propulsion devices14a,14bare controlled to travel from waypoint to waypoint, as described above.

The nuances of any particular waypoint tracking method and the exact way that data is communicated from the user input device to the autopilot system60and/or controller34are not focuses of the present disclosure. Rather, particular additional information that a user is able to input via the user input device, how this information may be input, association of this information with each individual waypoint, how this information is associated with each individual waypoint, and the controller's capability to actuate the marine propulsion devices according to this information are described in detail herein below.

Throw ah research and development, the present inventors realized that operators of a marine vessel will very rarely use a cruise control function while they are operating in waypoint tracking mode. This could be because the cruise control function is accessible via a separate screen on the chart plotter or a separate gauge altogether, rather than the same screen on the chart plotter that was used to select the waypoint tracking mode. Whatever the reason, the present inventors have realized that generally when operating in a waypoint tracking mode, an operator of a marine vessel will control the speed of the marine vessel and/or engine manually by manipulating a throttle device. This means that the operator must continually be aware of things such as speed limits, no wake zones, shallow water, crossing under bridges, fuel economy, etc. as the vessel travels along the route. The present inventors realized that it would helpful to have a single interface, and in fact a single screen, for inputting and/or selecting both a geographical location to which to travel, and a speed at which to travel to that geographical location.

FIG. 2illustrates one example of a system10for controlling position and speed of a marine vessel12propelled by a marine propulsion device14along a route comprising a plurality of waypoints. An input source, such as a user interface18, shown here as a chart plotter, is also shown inFIG. 2. The user interface18renders a screen20, which may be an interactive touch-sensitive screen, on which a route22comprising a plurality of waypoints24a,24b,24c, and24dis shown. Although only four waypoints24a-24dare shown in the route22, it should be understood that fewer or more waypoints could be provided for a given route. The screen20also renders a map26, which shows the different bodies of water and land in the general geographical area in which the marine vessel12is currently operating.

According to the present disclosure, the input source provides the plurality of waypoints to the controller34, and each individual waypoint in the plurality of waypoints is associated with a respective operator selected desired speed of the marine propulsion device14. For example, the user interface18renders the above-mentioned screen20, whereby an operator of the marine vessel12can associate each individual waypoint24a-24din the plurality of waypoints with a respective desired speed of the marine propulsion device14. In the example where the input source is a different device communicating with the controller34via a network connection or a drive or other storage device communicating with the controller34via a USB or similar port, the operator can input the geographical coordinates and associate them with respective desired speeds, and this data can then be saved on a remote computer or on a storage device for later uploading to the controller34. In one example, the desired speed of the marine propulsion device14is the speed of the marine vessel12, which may be described in units of miles per hour, kilometers per hour, or any other velocity value. In another example, the desired speed of the marine propulsion device14is a speed of an engine16powering the marine propulsion device14, and may be expressed in units of rotations per minute (RPM).

The system10further includes a position determination device28(e.g. GPS receiver29,FIG. 11that determines an actual geographical location of the marine vessel12. The position determination device28could alternatively be a compass80, an IMU82, or a differential GPS receiver. The system10also includes a speed sensor that determines an actual speed of the marine propulsion device14. In the example where the desired speed is a vessel speed, the speed sensor could be a vessel speed sensor30such as a paddle wheel or a pitot tube attached to the marine vessel12. Alternatively, a measurement of speed over ground (SOG) could be determined by the position determination device28. In the example where the desired speed is a speed of the engine16, the speed sensor is an engine speed sensor32such as, for example, a tachometer.

The system10also includes the controller34, which, as described above, receives a given waypoint24a-24dand its respective desired speed from the input source, such as the user interface18. The controller34also receives the actual geographical location from the position determination device28and the actual speed from the speed sensor, such as engine speed sensor32or vessel speed sensor30. According to the present disclosure, the controller34compares the actual geographical location to the given waypoint, and compares the actual speed to the respective desired speed, and outputs commands to propel the marine vessel12to the given waypoint and concurrently to operate the marine propulsion device14at the respective desired speed. The controller may do so by sending commands to the engine16of the propulsion device14, as well as to any type of steering mechanism provided on the marine vessel12, such as to the propulsion device14itself. In the example where the desired speed is a vessel speed, the controller34may command a throttle valve of the engine16to open or close incrementally as controlled by a feedback loop until the desired vessel speed is reached. In the example where the desired speed is an engine speed, the controller34may command the throttle valve to open or close to a calibrated position that is predicted to achieve the desired engine speed.

The controller34may have architecture such as that shown inFIG. 3. The controller34may include a computing system300that includes processing system302, storage system304, software306, and input/output (I/O) interfaces such as an input source link308and a propulsion device (including engine) link310. The processing system302loads and executes software306from the storage system304, including a position and speed control software application module312. When executed by the computing system300, application module312directs the processing system302to operate as described herein in further detail to execute the position and speed control method.

Although the computing system300depicted inFIG. 3includes one application module312in the present example, it should be understood that one or more modules may provide the same operation. Similarly, while the description provided herein refers to a computing system300and a processing system302, it is to be recognized that implementations of such systems can be performed using one or more processors, which may be communicatively connected, and such implementations are considered to be within the scope of the description. The processing system302can comprise a microprocessor and other circuitry that retrieves and executes software306from storage system304. Processing system302can be implemented within a single processing device but can also be distributed across multiple processing devices or sub-systems that cooperate in existing program instructions. Examples of processing system302include general purpose central processing units, applications specific processors, and logic devices, as well as any other type of processing device, combinations of processing devices, or variations thereof.

The storage system304can comprise any storage media readable by processing system302, and capable of storing software306. The storage system304can 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, program modules, or other data. Storage system304can be implemented as a single storage device but may also be implemented across multiple storage devices or sub-systems. Storage system304can further include additional elements, such as a controller capable of communicating with the processing system302. Examples of storage media include random access memory, read only memory, magnetic discs, optical discs, flash memory, virtual memory, and non-virtual memory, magnetic sets, magnetic tape, magnetic disc storage or other magnetic storage devices, or any other medium which can be used to store the desired information and that may be accessed by an instruction execution system, as well as any combination or variation thereof, or any other type of storage medium. In some implementations, the storage media can be a non-transitory storage media. In some implementations, at least a portion of the storage media may be transitory. It should be understood that in no case is the storage media a propagated signal.

Input source link308provides a hardwired or wireless link to the input source19(seeFIG. 1), such as the user interface18(seeFIG. 2). It should be mentioned that the computing system, processing system, storage system, software, and application module could all be located within the module of the user interface18itself instead of within a controller34that controls other functions aboard the vessel, such as a helm controller. In that case, the user interface18could be directly linked to the engine16, or could be linked to the engine16via the controller34acting as a helm controller.

Besides being a chart plotter as shown inFIG. 2, the user interface18could alternatively or additionally include a mouse, a keyboard, a voice input device, a touch input device (including but not limited to a touch screen), a smart phone or tablet, a PDA, and other comparable input devices and associated processing elements capable of receiving user input from an operator of the marine vessel. Output devices such as a video display or graphical display can display an interface further associated with embodiments of the system and method disclosed herein. Speakers, printers, and other types of output devices may also be included in the user interface18.

Referring back toFIG. 2, the system10according to the present disclosure is capable of operating such that a particular speed (vessel or engine speed) can be associated with a particular waypoint in one of many different ways. In one example, the user interface18includes push buttons36with which the operator can interact with the user interface18. Additionally or alternatively, the screen20can be an interactive touch-sensitive screen that allows the operator to touch images of buttons on the screen20itself in order to select particular functions. In this case, the push buttons36may be used to display a particular screen, and then the touchscreen20may be used to select a specific menu or function on that screen. Alternatively, only push buttons36or only images of buttons on the screen20can be used to interact with the user interface18. The exact way in which the operator interacts with the push buttons36and/or images of buttons on the screen20(collectively, buttons) is not limiting on the scope of the present disclosure.

In one example, the buttons allow the operator to manually associate each given waypoint24a-24din a route22with a respective desired speed. For example, a user may touch the screen20or place a cursor on the map26to create a new waypoint for a new route or to add a waypoint to an unfinished route. In the lower left-hand corner ofFIG. 2, a pop-up menu27is shown to illustrate what might be displayed on the screen20if the user inputs or selects waypoint24b(here “Waypoint2”). Instead of creating a new waypoint and associating that new waypoint with a desired speed, the operator could alternatively select an already-defined waypoint from an already-charted route22by placing a cursor over the waypoint or by touching the waypoint on the touchscreen20, and could insert a speed value to be associated with traveling to that waypoint.

A more detailed pop-up menu37is shown in toFIG. 4, via which an operator can individually input longitudinal and latitudinal coordinates for a waypoint as shown at box38, and can label this waypoint as shown at box40. The operator may then select from a dropdown menu, shown at42, whether he would like the desired speed associated with the particular waypoint to be a vessel speed as shown at44, or an engine speed as shown at46. The operator may enter the numerical value for the desired speed at box48. The operator can also choose to delete the waypoint by pressing the button shown at50, to cancel entry of the waypoint by selecting the button at52, or to save the waypoint by selecting the button at54. Notably, this pop-up menu37is accessible from the very same screen view as that which was used to input and/or select waypoints and/or routes. In fact, the pop-up menu37may show up in the foreground of the screen, while the map26and route22remain displayed in the background. Thus, the operator does not need to access a different screen view or interact with a different gauge in order to directly associate a waypoint with a particular speed.

The operator may additionally or alternatively be able to manually associate each of the waypoints24a-24din the plurality of waypoints with a single desired speed. In one example, the plurality of waypoints may comprise all of the waypoints (e.g.24a,24b,24c,24d) in a particular route22. In another example, the plurality of waypoints may comprise only a subset of the waypoints in the route22. For example, the operator could use a cursor or his finger to select only waypoints24cand24d, which would be a subset of the entire route22, and then associate a single desired speed with both of the waypoints24c,24d. The operator could subsequently select the waypoints24aor24band associate different speeds with each of these waypoints. In other words, the user interface18, including touchscreen20, may allow the operator to select the subset of waypoints by individually selecting each waypoint to be included in the subset from the map26rendered on the display screen20.

In another example, the touch sensitive display screen20may allow the operator to select the subset of waypoints by drawing a perimeter56around the subset (in this case still including waypoints24cand24d) on the map26rendered on the display screen20. The operator could create this perimeter56by touching the touch sensitive display screen20and circling the waypoints24c,24dwith his finger, or could use a cursor to circle the waypoints24c,24don the map26. Many other ways, such as by scrolling through a list of waypoints and selecting only a subset, could be used to select a subset.

The user interface18may also include a button (push button36or image of a button on screen20) that allows the operator to select a function by which the controller34flags any waypoints for which the respective desired speed exceeds a known waterway speed limit for a geographical area containing the waypoint. For example, referring back toFIG. 4, the user may access this function by selecting the “More options” button58from the waypoint pop-up menu and may then select a sub-option to flag the waypoint if it exceeds a known speed limit for the area in which the geographical coordinates entered at box38are located. In another example, one of the push buttons36shown inFIG. 2can be labeled as a “Speed limit check” button and can be used to check all of the waypoints in the route22, or a selected subset of the waypoints, for compliance to known speed limits. In yet another example, referring toFIG. 5, a “Menu” button64situated at the bottom of the screen20can be used to access a pop-up menu option (from pop-up menu67) to flag any waypoints that exceed known speed limits. Again, this menu button64would be accessible from the very same screen on which the map26and route22are displayed, and would not require the operator to navigate away from the waypoint tracking screen. In one example, once the operator has selected the speed limit check function, the controller34may cause the display screen20to highlight on the map26the waypoints24a-24dfor which the respective desired speed exceeds the speed limit. For example, these waypoints could be shown in a different color, could flash in and out of view, or could be circled on the map26so as to bring them to the attention of the operator.

In another example, again referring toFIG. 5, the user interface18includes a button (e.g. “Menu” button64) that allows the operator to select a function by which the controller34automatically changes the respective desired speeds of each flagged waypoint to the known speed limit for the geographical area containing each flagged waypoint. Additionally or alternatively, the user interface18may include a button (e.g. “Menu” button64) that allows the operator to select a function by which the controller34automatically associates each given waypoint in the plurality of waypoints with a target speed based on a known waterway speed limit for a geographical area containing the given waypoint. This would allow the operator to travel at maximum allowed speeds in different waterway areas. The speed-limited areas and/or no wake zones could be shown on the map26in different colors, could be outlined in dashed lines, or could be brought to the operator's attention in any number of ways. The controller34could determine when a speed limit applied by checking the current geographical position from the position determination device28, or future geographical position based on known speed and known location, with the data underlying the speed zones shown on the map26.

Referring back toFIG. 2, as mentioned briefly above, it need not be a controller34that is separate from the user interface18that performs the functions of associating the desired speeds with the given waypoints. Instead, the user interface18could be provided with its own controller, memory, and other hardware and, software components for carrying out the method of the present disclosure. In one example, once the controller located at the user interface18has associated a desired speed (whether that desired speed is manually chosen by the operator or automatically chosen according to a known speed limit) with the geographical coordinate, the coordinate and its associated speed are sent to a separate controller, here shown at34, which can incorporate both an autopilot system60and a cruise control system62. The autopilot system60may be used to control the steering position of the propulsion device14. The cruise control system62may be used to compare the actual and desired speeds (whether they are vessel speeds or engine speeds) with one another and to send commands to the throttle valve of the engine16in order to achieve the desired speed. This can be done according to known feedback algorithms, such as PID control algorithms.

Again referring toFIG. 5, the operator may also use the touchscreen20to select a “Cruise” button66, in which case a pop-up menu68as shown inFIG. 6may appear. This pop-up menu68may allow the operator to change the speed associated with a particular waypoint while on the go. For example, the operator could change his choice between controlling for vessel speed or engine speed using the dropdown box70, and/or could enter a different numerical value for the speed at box72. Alternatively, the operator could use the up and down arrows shown at74to increase or decrease the numerical value of the speed by given increments. The user could also disable or enable the cruise function with the buttons shown in the pop-up menu at76and78. The disable button76would allow the operator to take hack control of the speed of the marine propulsion device14, rather than having the speed be controlled automatically by the one of the methods described herein above.

Other functions are accessible via the various menu buttons on the screen20. For example, the operator can select to have a waypoint be automatically associated with a speed of the marine propulsion device14that achieves the best fuel economy based on known waterway conditions, trim position of the propulsion device, and/or measured load on the propulsion system. This associated speed might therefore automatically change while traveling from one waypoint to another. If this caused too many speed changes, the operator could then use the “Cruise” menu button66to enable cruise at a particular speed value instead of using the varying speed associated with best fuel economy. The operator could also use the menu options to choose to display a continuously updated arrival time at which the next waypoint, or a final waypoint, will be reached. The operator could try inputting different speeds for different waypoints to see how this changed the estimated arrival time. Again, each of these menu options would be accessible from the user interface18, such as the chart plotter shown inFIG. 2, from the same screen on which the map26, route22, and waypoints are shown. The map26could remain in the background while the user selects any of the speed control functions described herein. This would present an easy way for the operator to associate speeds with different waypoints before or while operating the propulsion system in the waypoint tracking mode.