Patent Grant
8468964
The present invention is in the field of thrust control for propeller driven watercraft such as a boat. More particularly, the present invention relates to methods and arrangements to redirect a thrust generated by a propeller via a control surface for a watercraft to provide a non-forward thrust. Many such embodiments may advantageously provide finer and/or quicker adjustments to the net thrust, steering, wake control, tilt control and/or other control via the redirected thrust.
The watercraft designs differ the size, shape, and propulsion of the watercrafts. For instance, contemporary watercraft designs implement sails, jet engines, fans, water-jet propulsion drives, paddle drives, and motor-driven propellers for propulsion. Each type of propulsion has unique advantages and disadvantages.
People use watercrafts for a variety of recreational and commercial activities, from pulling water skiers to transporting oil to racing. The large variety of uses for watercrafts have inspired specialized and general purpose designs of various sizes, shapes, and means of propulsion; including propeller driven motorized versions; which are generally available as an inboard, outboard or inboard-outboard. Watercrafts with inboard drives (“inboards”) typically have a motor mounted in the watercraft and a fixed-position propeller. Inboards are inherently simpler designs than watercrafts with outboard motor drives (“outboards”) or watercrafts with inboard-outboard drives (“IOs”), or stern drives, so they are usually lower cost and lower maintenance. Inboards typically include a rudder in the prop wash of the propeller to steer the watercraft. Placing the rudder in the prop wash improves the steering by increasing the amount of water being redirected by the rudder. In reverse, the rudder is not in the prop wash and, as a result, the inboards are difficult to maneuver in reverse, which is especially troublesome when attempting to maneuver the watercraft to a dock, onto a trailer or when preparing to pull a water skier.
Large watercrafts such as boats that are greater than 30 meters in length are typically inboards due to the cost and maintenance advantages of inboards. Unlike smaller boats such as boats that are about 3 to 8 meters in length, the added cost and weight to mount side thrusters is less significant for large boats.
Outboards have one or more outboard motors mounted at the stern of the boat. A motor is located at the top of the outboard drive and is connected to a propeller at the bottom of the drive via a transmission and a substantially vertical shaft.
In many outboard designs, the outboard drive may rotate approximately 110 degrees in the horizontal plane, depending upon the design, to provide steering and can be tilted vertically to raise the propeller above the bottom of the hull to protect the propeller when the watercraft is in shallow water or transported or stored out of water. Because outboard drives typically have only one reverse, and one forward gear, the gear may provide too much thrust even in idle to easily dock the boat, which forces the person docking the boat to repeatedly switch between in gear and neutral to achieve slower speeds than possible at idle. Also, when maneuvering to remove slack in a ski rope, idle speed is typically too fast.
IOs have stern drives, which locate the motor inside the boat at the stern. The motor is connected through the transom to an outboard drive unit similar to the bottom half of an outboard motor. IOs provide steering by allowing the outboard drive unit to pivot about a substantially vertical axis. IOs are far more popular than standard inboards partly because they are easier to steer, especially in reverse. Yet, idle speed in both forward and reverse is typically too fast for docking and for removing slack in a ski rope.
The problems identified above are in large part addressed by methods and arrangements to redirect thrust generated by a propeller of a watercraft to provide a reverse and/or sideways thrust. One embodiment provides an apparatus to redirect a thrust generated by a propeller for a watercraft. The apparatus may comprise a control surface to redirect the thrust from the propeller based upon a position of the control surface with respect to the propeller, wherein the redirected thrust comprises a component of non-forward thrust; and a first member to couple with the watercraft to apply force to adjust a spatial relationship between the control surface and the propeller to position the control surface at least partially within an area in which prop wash is to be expelled by the propeller.
One embodiment provides a method for a watercraft to redirect a thrust generated by a propeller via a plate. The method generally involves applying force via a first member to adjust a spatial relationship between the control surface and the propeller to position the control surface at least partially within an area in which prop wash is to be expelled by the propeller; and redirecting the thrust from the propeller via the control surface based upon the spatial relationship of the control surface with respect to the propeller, wherein the redirected thrust comprises a component of non-forward thrust.
Another embodiment provides a watercraft capable of redirecting a thrust generated by a propeller. The watercraft may comprise a hull having a motor coupled with the propeller to rotate the propeller to expel prop wash to generate the thrust; a control surface to redirect the thrust from the propeller, based upon a position of the control surface with respect to the propeller, wherein the redirected thrust comprises a component of non-forward thrust; and a first member to couple with the hull to apply force to adjust a spatial relationship between the control surface and the propeller to position the control surface at least partially within the prop wash.
A further embodiment provides a retrofit kit for a watercraft to redirect a thrust generated by a propeller. The retrofit kit may comprise a rigid member to couple with the watercraft; a non-rigid joint to couple with the rigid member; and a control surface to couple with the rigid member via the non-rigid joint to restrict movement of the control surface in at least one direction and to apply force to the control surface to position the control surface in water within an area in which prop wash is to be expelled by the propeller to reflect the thrust in response to generation of the thrust by the propeller, based upon a position of the control surface with respect to the propeller, to redirect the thrust, wherein the redirected thrust comprises a component of non-forward thrust.
A further embodiment provides a controller to redirect a thrust generated by a propeller via a plate for a watercraft. The controller may comprise a sensor to detect the position of the control surface, a memory to store a current position of the control surface with respect to the propeller; logic coupled with the other controller elements to determine an adjustment for a spatial relationship between the control surface and the propeller based upon the current position; and a driver interface to instruct a driver to adjust the spatial relationship between the control surface and the propeller to position the control surface at least partially within prop wash of the propeller to redirect the thrust, wherein redirection of the thrust by the control surface produces a component of non-forward thrust.
Yet another embodiment provides a control system for a watercraft to redirect a thrust generated by a propeller. The control system may comprise a control surface to redirect the thrust from the propeller based upon a position of the control surface with respect to the propeller, wherein the redirected thrust comprises a component of non-forward thrust; an attachment member coupled with the watercraft to apply force to modify the spatial relationship between the control surface and the propeller to position the control surface at least partially within an area in which prop wash is to be expelled by the propeller; a driver to transmit the force from the watercraft to the attachment member; and a controller to determine an adjustment for the spatial relationship between the control surface and the propeller and the communication with the driver to implement the adjustment.
A further embodiment provides a machine-accessible medium containing instructions to redirect a thrust generated by a propeller via a control surface for a watercraft, which when the instructions are executed by a machine, cause said machine to perform operations. The operations may comprise applying force to position the control surface in water within an area in which prop wash is expelled by the propeller; and redirecting said thrust via the control surface based upon a position of the control surface with respect to the propeller, wherein the redirected thrust comprises a component of non-forward thrust.
A still further embodiment provides a database to redirect a thrust generated by a propeller via a plate for a watercraft. The database may comprise thrust data to relate a current spatial relationship between the control surface and the propeller with a component of a current redirected thrust; data to relate the components of the current redirected thrust and/or boat angular and rotational velocity with a operator specified propulsion of the watercraft; and a formula to determine an adjustment to the spatial relationship based upon a difference between the current redirected thrust and a new propulsion, the adjustment to position the control surface at least partially within an area in which prop wash is to be expelled by the propeller to effect the new propulsion; wherein the adjustment is indicative of an application of force to implement the adjustment.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which, like references may indicate similar elements:
The following is a detailed description of example embodiments of the invention depicted in the accompanying drawings. The example embodiments are in such detail as to clearly communicate the invention. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. The detailed descriptions below are designed to make many such embodiments obvious to a person of ordinary skill in the art.
Generally speaking, methods and arrangements to redirect a thrust generated by a propeller of a watercraft to provide a non-forward thrust are disclosed. More specifically, embodiments comprise a control surface such as a plate to redirect the thrust in response to generation of the thrust by the propeller. Based upon a position (i.e., distance and orientation) of the control surface with respect to the propeller, the redirection generates at least a component of non-forward thrust. By redirecting a component of the thrust back toward the propeller, the propulsion of the watercraft is the net effect of all the thrusts so the net forward or reverse and port or starboard thrusts can be adjusted in fine increments. The granularity of the adjustments is related to the increments in adjustment of the spatial relationship between the propeller and the control surface. For instance, by adjusting the distance between the control surface and the propeller, the magnitude of the thrust that impacts the control surface can be adjusted. Therefore, in such embodiments, the net thrust can be adjusted in increments related to the smallest distance that, e.g., the control surface can be moved away from the propeller.
By redirecting most or all of the thrust back toward the propeller, some embodiments may advantageously be capable of reverse propulsion (as well as forward propulsion) without a reverse gear or with no transmission at all, reducing manufacturing and maintenance. Note that the reverse propulsion generated by, e.g., positioning the control surface in the prop wash of the propeller or orienting the propeller to direct the thrust toward the control surface while the propeller is generating a forward thrust, can advantageously provide a significant braking action for the watercraft without damaging the gears. Transmissions of contemporary watercraft provide a reverse gear but shifting the transmission into a reverse gear while at greater than idle speed or RPM may damage a transmission. In embodiments of the present invention the control surface may be attached or integrated into the hull of the watercraft in a manner that can handle the forces involved with the abrupt transition from forward thrust to reverse thrust at high speeds. Thus, some embodiments of the invention offer significantly enhanced safety and acceleration by allowing the boat operator to transition quickly between a full-throttle, forward, reverse or, neutral thrust. Accordingly, some embodiments may also comprise safety belts or similar restraints for passengers and/or cargo. Further embodiments implement a speed or RPM limitation on shifting thrust direction positions.
Many embodiments facilitate adjustment of the angle of the control surface with respect to the propeller, which changes the angle of incidence of the prop wash on the control surface. Adjusting the angle of incidence of the prop wash on the control surface adjusts the direction and magnitude of the component of non-forward thrust with or without significantly changing the distance between the plate and the propeller. Several embodiments facilitate both adjustments to the distance between the control surface and the propeller as well as adjustments to the angle of incidence of the thrust on the control surface, advantageously providing the watercraft operator with the ability to simultaneously, independently, and incrementally adjust magnitude and direction of redirection of redirected thrust. Other embodiments adjust the amount of prop wash that impinges upon the control surface for control of forward/reverse thrust while independently adjusting the angle of impingement to adjust the direction of redirected thrust. Other embodiments transition from no redirection of prop wash through upward or downward redirection of prop wash which has no steering effect to redirection of prop wash while independently controlling the magnitude of port or starboard redirection of prop wash.
Further, the net thrust may be directed forward, backward, to port, to starboard, or any other direction, depending upon the adjustability of the angle of the control surface with respect to the propeller and the propeller with respect to the watercraft. For example, embodiments that adjust the angle of the control surface may redirect a component of the thrust in a direction other than back toward the bow. In such embodiments, the control surface may be angled to redirect a component of the forward thrust to port to turn the watercraft to the starboard or vice versa. Redirecting the forward thrust or a portion thereof sideways, the watercraft may advantageously turn at, e.g., one-fifth the turning radius of the watercraft without utilizing the control surface. It may even rotate in place.
If a component of the thrust is directed downward, the stern of the watercraft may be raised. Similarly, if a component of the thrust is redirected upward, the stern may be lowered, possibly to change the size of the wake created by the watercraft.
Some of these embodiments comprise a controller designed to take advantage of the fine adjustments to control the speed of the watercraft, generate a wake of a desired shape, maintain the watercraft substantially level, enhance steering capabilities of the watercraft, or any other application for the redirected thrust. For example, one embodiment includes two plates. The angle of the plates may be controlled independently to allow one component of thrust to be redirected upward, and another component to be redirected downward, in addition to the reverse thrust component. Adjustment of net thrust whether forward or reverse may provide speed control while the net of the upward and downward thrusts may provide control over the bow-to-stern angle of the watercraft. Other embodiments comprise more or less than two control surfaces and some embodiments pivot control surfaces along different axes such as port-to-starboard rather than or in addition to pivoting upward and downward. In further embodiments, control surfaces are fixed or substantially fixed and the propeller is moved to adjust the magnitude and the angle of impact of thrust on the control surfaces. In alternative embodiments, the propeller moves up/down to control the ratio of forward to reverse thrust and the control surface(s) are rotated about a substantially vertical axis or moved port to starboard to independently control steering.
Some embodiments may comprise a database with data and/or formulas to facilitate adjustments by the controller responsive to instructions from the watercraft operator. Further embodiments comprise one or more sensors adapted to provide the controller with data to determine adjustments for the control surface. For example, several embodiments may comprise a pressure sensor coupled with the control surface, a global positioning system (GPS), and/or a speedometer such as a paddle type speedometer. The controller in such embodiments may then be able to navigate the watercraft between destinations. In one such embodiment, the controller is adapted to help the boat operator execute a complex set of maneuvers by adjusting the speed of the boat and helping the boat operator steer the watercraft in the desired direction. In particular, the route may be preprogrammed and stored in the controller so the controller may predict, at least approximately, when certain maneuvers should be executed. Thus, the controller can either predict maneuvers or be responsive to the boat operator's initiation of a maneuver.
While portions of the following detailed discussion describe embodiments of the invention in specific types of watercraft with particular types of instruments, sensors, numbers of control surfaces, shapes of control surfaces, and other equipment, embodiments with other watercraft and/or arrangements of equipment that comprise a submersed propeller to generate a thrust are also contemplated.
Turning now to the drawings,
Boat 100 comprises a hull 105 with a transom 110, controller 115, a steering and instrument panel 120, a throttle control 125, a driver cabinet 130, motor 135, control surface 150, and propeller 155. Controller 115 comprises an interface for the boat operator to move or reorient control surface 150 to adjust the position of control surface 150 with respect to the thrust generated by propeller 155. In the present embodiment, controller 115 comprises a processor-based controller adapted to adjust the position of control surface 150 based upon input from the boat operator and from sensors on the boat such as speed sensor 170. In other embodiments, controller 115 may provide manual control of the position of control surface 150 and, in some of these embodiments, the manual control may be power-assisted via, e.g., a hydraulic system.
Controller 115 may facilitate adjustment of the angle of control surface 150 with respect to thrust generated via propeller 155 and/or adjustment of the distance between control surface 150 and propeller 155. And/or adjustment of amount of control surface in prop wash. Several embodiments adjust the angle of control surface 150 with respect to the thrust generated by propeller 155. Adjusting the angle of control surface 150 adjusts the magnitude of the component of thrust redirected back toward propeller 155.
When adjusting the net thrust by modifying the angle of control surface 150, a second component of the thrust may be redirected in a direction other than back toward propeller the bow of boat 105. The second component of the redirected thrust may advantageously be redirected in a way to enhance maneuverability, leveling, or the like of boat 100. For instance, when turning to port, control surface 150 may be angled to redirect a component of the thrust to port, enhancing the ability of boat 100 to turn to port. In some actual experiments, one embodiment allowed a boat to turn in place.
As another illustration, the redirected thrust reflected by control surface 150 may maintain the level of boat 100. The current embodiment utilizes one control surface that is a plate. The plate can redirect a component, e.g., in one general direction to raise the stern and/or raise the port side of boat 100, or to lower the stern and/or lower the starboard side of boat 100. In other embodiments, additional control surfaces may be implemented to increase the flexibility of adjustments. For instance, when the boat operator does not want to affect the port-to-starboard level of boat 100 while turning, controller 115 may redirect one component of the thrust upward and one component of the thrust downward to maintain the port-to-starboard level.
Looking to
Boat 100 comprises arms 145, 165 and 167 to apply force to control surface 150 to maintain the position of control surface 150. In the present embodiment, arms 165 and 167 are hydraulically adjustable via controller 115 (shown in
Controller 115 may maintain the level of boat 100 by adjusting the magnitude of components of redirected thrust to dynamically compensate for changes in one or more angle(s) of boat 100. For instance, boat 100 may comprise level sensors for the port-to-starboard angle, bow-to-stern angle and possibly other angles. In some embodiments, these sensors are combined in one or more gyroscope-based sensors. Controller 115 may detect changes in the level of boat 100 based upon data collected by the sensors and change the angle of control surface 150 to redirect a component of thrust in a direction determined to compensate for the change in the angle of boat 100.
In further embodiments, controller 115 may ignore or disregard low frequency changes in angles of boat 100 such as the bow-to-stern angle and may only compensate for higher frequency changes. For instance, repetitive lower frequency changes in the bow-to-stern angle of boat 100 may be indicative of large waves with respect to the size of boat 100 so compensating for the angle changes based upon such low frequency changes may be counter-productive with regard to propulsion. In many embodiments, the threshold between high frequency changes and low frequency changes may be programmable and/or pre-set.
In some embodiments, rather than or in addition to modifying the angle of control surface 150, the boat operator may modify the distance of control surface 150 from propeller 155 to adjust the magnitude of components of redirected thrust. Such embodiments adjust the magnitude of the thrust impacting control surface 150 because an increase in the distance between control surface 150 and propeller 155 decreases the amount of thrust reversal.
Referring back to
Speed sensor 170 is a paddle-type sensor that comprises a paddle wheel partially submerged in the water. As boat 100 moves forward or backwards, the paddle wheel spins due to pressure by the passing water at a rate. In many embodiments, controller 115 couples with speed sensor 170 to monitor the speed of boat 100.
Throttle control 125,
In some embodiments, control over the position of control surface 150 may be power-assisted utilizing the same hydraulic or other power system which controls trim adjust that some boats have. In other embodiments, a separate system may be provided to adjust the position of control surface 150.
Motor 135 is an outboard motor in the present embodiment that couples with propeller 155 via a transmission. In the present embodiment, control surface 150 compliments the use of gears by advantageously providing finer control over the net thrust offered by propeller 155 via motor 135 at idle speed and offers reverse propulsion without shifting the transmission into a reverse gear.
Also note that for embodiments in which the transmission is shifted into a reverse gear, a hinge or other member may physically limit the movement of control surface 1005 toward propeller 1005 to prevent control surface 1005 from contacting propeller 1010. Control surface 1005 may then provide a substantially consistent interference with the water drawn by propeller 1010. Thus, the reverse, or negative, thrust is reduced by a relatively constant proportion.
At lower RPMs, control surface 150
Control surface 1005 is adapted to reflect thrust generated by propeller 1010 when the propeller is producing a forward thrust and, in some embodiments, interfere with water flow to propeller 1010 when the propeller is producing a reverse thrust. In another embodiment, control surface 1005 is coupled with boat 150
Control surface 150,
Control surfaces may be of any shape. For instance, control surface 150 may be rectangular, circular, elliptical, or the like. Control surfaces may also be flat or comprise some sort of curvature. For example, control surface 610 of
Further, control surfaces may be any size from slightly smaller than the diameter of propeller to larger than the diameter of propeller so long as the control surface can produce a sufficiently large reverse thrust. Experiments have shown that reverse thrust sufficient to propel a boat backwards is achievable with a flat control surface that is only slightly larger than the diameter of the propeller and a slightly larger plate with forward pointing edges provides greater reverse thrust.
Control surface 150 may also advantageously block foreign objects from impacting propeller 155 when traveling in reverse. For example, when boat 100 is maneuvering into a position to pull a skier, control surface 150 may prevent the skier from accidentally being injured by propeller 155 and may prevent the ski rope from becoming entangled in propeller 155.
As shown in
Referring again to
In
Turning to
When propeller 810 is producing a forward thrust, control surface 805 is adapted to reflect the forward thrust to produce a component of reverse thrust. In some embodiments, the component of reverse thrust is sufficient to propel boat backwards. In further embodiments, control surface 805 may be angled in other directions such as to port or starboard to enhance steering capabilities. For example, in one embodiment, inboard 800 is adapted to angle control surface 805 to port or starboard in response to turning rudder 830 to port or starboard.
In many embodiments, raising the propeller when under forward power requires 10-100 times less force compared to an IO drive or outboard when under full forward thrust. This means that if a person, the lake bottom or other object is hit, raising the propeller to prevent propeller damage and to save the life of the swimmer can be more quickly and safely accomplished.
Boats 900 and 950 also comprise a skag 930 to detect an obstacle prior to the obstacle hitting the propeller. Skag 930, upon contacting an obstacle, may trigger a driver such as a hydraulic, electrical, or pneumatic system to automatically retract arm 910 to raise propeller 810 behind transom 825 of boat 900. Additionally, for safety, rudder 925 may be adapted to hinge up if it hits something. In
In
Boat 950 has a shaft 960 with a universal joint 955 to facilitate raising and lowering propeller 810. Adjustable member 965 may couple with a driver system such as a hydraulic system to raise and lower shaft 960. In further embodiments, adjustable member 965 may be manually controlled by a boat operator.
Turning to
While
Control surface 1005 comprises a spring-loaded hinge that provides resistance against forward thrust generated by propeller 1010. Spring-loaded hinge 1015 may also limit movement of control surface 1005 to prevent control surface 1005 from impacting propeller 1010. In
Simpler embodiments may comprise control surface 1005, spring-loaded hinge 1015, and coupling 1022 adapted to attach control surface 1005 to rudder 1020. In some embodiments, coupling 1022 may be universal, being adaptable for outboards, IOs, inboards, or other watercraft. In other embodiments, coupling 1022 may be more specifically designed for one or more types of watercraft. In still further embodiments, retrofit kits may be adapted for specific manufacturers and/or models.
Further embodiments comprise an adjustable arm adapted to couple with an existing or new driver such as a hydraulic pump, an electrical motor, a pneumatic compressor, or the like.
Many embodiments of retrofit kits may comprise a controller such as controller 115 of
Several embodiments comprise sensors specifically adapted to work with a controller like controller 115. In some embodiments, the sensors are wireless and/or hardwired via electrical conductors and/or fiber optic filaments. For example, some embodiments comprise a pressure sensor attached to control surface 1005.
Referring now to
Controller(s) 1110 may couple with sensor(s) 1130 to determine adjustments for control surface(s) 1128 and, in some embodiments, when to implement those adjustments. For example, the boat operator may wish to back up into a dock for the boat. The boat may have one reverse gear that provides too much power even when the motor(s) 1112 are at idle to easily maneuver the boat into the dock in reverse. Further, the steering of the boat may be fairly poor when driving the boat in the reverse gear so the boat operator may instruct controller(s) 1110 to produce a reverse thrust in forward gear to provide enhanced steering capabilities. Controller(s) 1110 may respond by applying force to control surface(s) 1128 via driver(s) 1120 and monitoring steering 1170 to dynamically adjust an angle of control surface(s) 1128. Applying the force may insert one or more of control surface(s) 1128 into the prop wash of propeller(s) 1115 to create a component of reverse thrust that is greater than components of forward thrust so the boat is propelled in reverse. Then, by monitoring steering adjustments or changes, and tracking those changes with complimentary changes in the horizontal angles of one or more of control surface(s) 1128, controller(s) 1110 may advantageously provide the boat operator with enhanced maneuverability.
In the present embodiment, controller(s) 1110 may be adapted to interface with motor(s) 112 to adjust the forward and/or reverse thrust provided by propeller(s) 1115. For example, the boat operator may instruct controller(s) 1110 to maintain a specific speed and controller(s) 1110 may interface with motor(s) 1112 to turn off or on one or more motors(s) to adjust the speed of the boat. Controller(s) 1110 may also adjust the RPMs of one or more of motor(s) 1112 in addition to adjusting the position of control surface(s) 1128 to maintain that speed while maintaining the boat substantially level with the water line. Further, controller(s) 1110 may monitor the current speed by monitoring, e.g., the control surface pressure 1165 or speed 1152, as well as the heading via direction 1154.
Driver(s) 1120 may couple with controller(s) 1110 to make adjustments to the position of control surface(s) 1128. Driver(s) may comprise a hydraulic system 1122, a pneumatic system 1124 and/or an electrical system 1126. In some embodiments, controller(s) 1110 is designed to work with more than one of driver(s) 1120. In further embodiments, controller(s) 1110 may comprise an interface for one of driver(s) 1120. In still further embodiments, controller(s) 1110 may comprise an interface for other types of drivers that may be adapted to adjust the position of control surface(s) 1128.
Sensor(s) 1130 may provide data to controller(s) 1110 about the current status of the boat such as the level of the boat via level switch(es) 1140, the linear and/or rotational velocity 1150 of the boat, the position of the boat 1160, the control surface pressure 1165 for one or more of control surface(s) 1128, steering adjustments 1170, linear and/or rotational acceleration, inclination, and the like. In fact, some embodiments may comprise a gyroscope or other gyro based sensor. Level switch(es) 1140 may provide controller(s) 1110 with the angle of the boat bow-to-stern 1142, port-to-starboard 1146, and/or other direction 1144 so controller(s) 1110 can maintain an angle indicated by the boat operator. In some embodiments, rather than comprising multiple switches such as mercury switches, level switch(es) 1140 may comprise a gyro based level switch 1148 that provides level data for multiple angles.
Velocity 1150 may comprise one or more sensors to provide data related to the velocity vector of the boat. For example, in some embodiments, velocity 1150 may comprise a compass to sense direction 1154 and speedometer to sense speed 1152. In further embodiments, velocity 1150 may interface with a global positioning system (GPS) to determine the velocity based upon differences in positions of the boat over time intervals.
The position sensor 1160 may comprise a GPS, may triangulate the current position relative to one or more other reference signals and/or may determine the position of the boat relative to a start position based upon calculated changes to the boats position. Steering adjustment sensor 117 may interface with a steering system for the boat such as by coupling to a rudder and measuring the angle of the rudder to determine adjustments in the direction of the boat made by the boat operator.
Buttons 1220 and 1225 comprise a recalibrate button 1220 and a mode button 1225. Recalibrate button 1220 may, when activated by the boat operator, initiate a recalibration sequence for controller 1240 and/or sensors coupled with controller 1210. For instance, depressing recalibrate button 1220 may cause processor 1245 to execute recalibration module 1265, causing controller 1200 to reread data from each sensor to determine the position of control surface 1128.
Mode button 1225 may change a mode of controller 1210 in response to activation. Changing the mode of controller 1200 may comprise, e.g., changing the information displayed on display 1215, changing between manual and automatic position updates, entering a customization, modifying speed, modifying control surface angle, modifying a distance between control surface 1128 and propeller 1115, and/or the like. For instance, if mode button 1225 is pressed, controller 1200 may change to the next mode in a sequence of modes. In other embodiments, pressing a button along with mode button 1225 may select a mode or advancement between modes in a different sequence. In further embodiments, buttons 1220 and 1225 may comprise buttons with the same and/or other functions incorporated into controller 1200.
Wheel 1230 may provide a means for adjusting the angle and/or distance of control surface 1128 with respect to propeller 1115. In further embodiments, one mode may facilitate the adjustment of the control surface with respect to a transom of the hull or some other point. For example, the boat operator may press mode button 1225 one or more times to enter a mode to modify the angle of control surface 1128. Once in the mode, display may provide a graphical representation of the angle of control surface 1128 with respect to propeller 1115 as well as a number representing the angle. The boat operator may then dial or turn wheel 1230 to adjust the angle up or down. In some embodiments, one mode may display, e.g., the speed of boat 100 of
In further embodiments, controller 1200 may allow the boat operator to adjust the speed directly by dialing wheel 1230. For instance, controller 1200 may determine adjustments to the angle and/or position of control surface 1128 to cause the indicated change in speed. In one embodiment, controller 1200 may also interface with the throttle system for boat 100 to modify the speed.
The architectural view 1240 of controller 1200 comprises a processor 1245, a sensor interface, a driver interface 1255, a steering interface 1256, a motor interface 1257, a user interface 1259, and a memory 1260. Processor 1245 may execute code in memory 1260 with data retrieved via sensor interface 1250 and/or stored in memory 1260 to control the position of control surface 1128 in accordance with input from the boat operator. For example, processor 1245 may execute code of user interface 1270 to interact with a boat operator to change the mode of controller 1200 to a mode for adjusting the angle of control surface 1128. User interface 1259 provides the physical level interface for processor 1245 to control display 1215, buttons 1220 and 1225, and wheel 1230. The boat operator may press mode button 1225, user interface 1259 may transmit the input to processor 1245, and, in response, processor 1245 may execute code of user interface 1270 to advance a pointer to point at code for a subsequent mode which may be, e.g., the mode for adjusting the angle of control surface 1128. In other embodiments, part or all of the components in controller 1200 may be implemented with state machines, other hard-coded logic, or the like rather than code and a general-purpose processor. In further embodiments, controller 1200 may implement other features. In still further embodiments, aspects of controller 1200 may be implemented with mechanical switches, cables, pulleys, and/or the like rather than being processor-based.
Sensor interface 1250 may provide interfaces for electrical, fiber optic, hydraulic, pneumatic and/or other types of sensors. Sensor interface 1250 may receive and/or convert data received from sensors for use by processor 1245. In present embodiment, processor 1245 may also execute code of calibration module 1265 to calibrate one or more of the sensors.
Driver interface 1255 provides interfaces for electrical, fiber optic, hydraulic, pneumatic and/or other types of drivers. For example, processor 1245 may instruct a pneumatic system to increase pressure via a valve to control surface(s) 1128 of
Steering interface 1256 may provide a physical interface for a steering system of the boat. For example, steering interface 1256 may provide controller 1210 with an ability to adjust the angle of a rudder. Motor interface 1259 may couple with a motor, which drives a propeller of the boat to provide controller 1210 with an ability to adjust the RPMs of the motor. For instance, for direct current (DC) electric motors, motor interface may output a signal to raise or lower the voltage applied to the motor to adjust the RPMs and torque available. For gas-powered motors, on the other hand, motor interface 1257 may provide control over a throttle or fuel injections to adjust the power output of the gas motor.
User interface 1259 may provide an interface between processor 1245 and display 1215, buttons 1220 and 1225, and wheel 1230. For instance, the boat operator may turn wheel 1230 to rotate a control surface of control surface(s) 1128 about an axis.
Memory 1260 may comprise volatile and non-volatile, and fixed and/or removable memory to store code and data to facilitate adjustment of control surface(s) 1128 by controller 1200. For example, memory may include read only memory (ROM), random access memory (RAM) like dynamic RAM (DRAM), flash, a hard drive, optical media, and/or other data storage. Memory 1260 may comprise calibration module 1265, user interface 1270, heuristic data 1275, other data 1278, formula(s) 1280, mode(s) 1285 and/or the like.
Calibration module 1265 may facilitate calibration of sensors and, in further embodiments, may automatically calibrate sensors by comparing sensed data from one or more sensors against the sensed data from one or more other sensors. More specifically, one or more sensors may be designated or considered accurate or self-calibrated and thus, controller 1200 may trust the data received from those sensors. For example, calibration module 1265 may comprise code for execution by processor 1245 that monitors a speedometer and calibrates the pressure sensor(s) 1165 for control surface(s) 1128. In a further embodiment, calibration module 1265 may monitor a calibration of the sensed position of the propeller based upon changes in propulsion responsive to the redirected thrust. For instance, the angle read for the control surface may not be consistent with the port-to-starboard tilt or the change in course recorded by a GPS so the calibration module 1265 may determine the actual position of a control surface based upon the tilt and/or the GPS data to calibrate the sensor that detects the position of the control surface.
User Interface 1270 may comprise code, which, upon execution by processor 1245, is adapted to provide instructions to user interface 1259 to display information on display 1215 and receive input from the boat operator via buttons 1220 and 1225, and wheel 1230. In further embodiments, display 1215 may comprise a touch screen or the like and user interface 1270 may comprise code to interpret pressure applied by the boat operator to various portions of display 1215.
Heuristic data 1275 may comprise data collected by controller 1200 to facilitate accurate adjustment of the position of control surface(s) 1128. For instance, heuristic data 1275 may comprise data related to, e.g., speed of the boat resulting from use of a propeller at certain RPMs and the pressure indicated by the control surface at different speeds and different angle. In some embodiments, a boat operator may also separately store data collected from use of the boat in different bodies of water, or even different areas of a body of water so the data may more accurately account for particulates in the water. In further embodiments, the heuristic data 1275 may be provided with controller 1200 and related to test data taken via the same type of boat, a similar boat, or a typical boat.
Other data 1278 may comprise data provided with controller 1200 or the boat upon which controller 1200 is to be installed. Other data 1278 may comprise theoretical data, constants, conversion factors, and/or further data selected to facilitate use of controller 1200 and the included code and/or logic by the boat operator. Other data 1278 may also comprise data indicating preferences of one or more boat operators.
Formulas 1280 may comprise one or more formulas provided with controller 1200 to calculate theoretical values for, e.g., the anticipated control surface position to cause the boat to turn within a particular radius. Formulas 1280 may further comprise formulas to dynamically calculate corrections for the position of control surface(s) 1128 to correct the course, pitch, tilt, roll, and/or the wake size and shape created by the boat based upon sensor data that is available to and/or may be available as an optional accessory for controller 1200.
Modes 1285 may comprise code to provide one or modes of use for controller 1200. For instance, one mode available to a boat operator may display an angle and distance for control surface(s) 1128 as values and another mode may display a two-dimensional or three-dimensional representation of the angle and distance of control surface(s) 1128. Some modes may allow the boat operator to adjust, e.g., the position of control surface(s) 1128 while displaying the effect of the changes on speed, an angle of the boat, or other. Further modes may allow the boat operator to execute code for dynamically controlling the boat. For example, one mode may cause controller 1200 to dynamically maintain the speed of the boat by adjusting the position of the control surface and/or the throttle for the motor. Many other modes are also contemplated.
A control lever 1305, such as wheel 1230 of
In many embodiments, a default position adjusts the spatial relationship of the control surface and the propeller to direct the prop wash away from the control surface as a fail-Safe. In particular, even the power system fails but the motor for the propeller still runs, the boat can maneuver back to dock without the assistance of the control surface. Many other arrangements are also contemplated.
Rotating control lever further may apply the opposite pressure on arm 1430 and turn control surface/propeller 1440 downward. A relief valve 1450 may allow the hydraulic fluid to escape into a reservoir to reduce the pressure in the system 1400 in case the pressure rises toward or to the maximum rated pressure of system 1400. For example, if an object impacts control surface/propeller 1440, the pressure in system 1400 may have a significant spike. Release valve 1450 may respond by releasing hydraulic fluid into the reservoir. Many other arrangements are also contemplated.
Referring now to
Columns 1510 provide data related to the motor, transmission, propeller, and control surface to calculate a theoretical thrust perceived by the control surface at different speeds. More specifically, RPMs determine how fast the propeller displaces water and the speed of the watercraft may determine the amount of resistance that is added due to the impact of water from water flow passed the boat rather than embodying the thrust generated by the propeller. The torque and transmission gear ratio provide an indication of the ability to change the speed. For instance, a controller may utilize the torque and transmission gear ratio to determine how much adjustment should be made to the throttle of the motor to maintain a constant speed.
The design of the propeller in terms of shape determines the quantity of water propelled by the propeller. For example, the propeller may comprise a single set of blades or more then one set of blades. One common propeller, often referred to as a dual propeller, comprises two sets of three blades. While requiring a greater torque from the motor at a particular RPMs, the propeller generates a greater magnitude of thrust.
The size or diameter of the propeller determines the diameter of the water column propelled by the propeller and the design of the control surface including the size and shape determines the portion of the water column that impacts the control surface, the portion of the surrounding water flow that impacts the control surface (providing a component of reverse thrust), and the net magnitude and direction of the redirected thrust.
Column 1520 comprises the calculated pressure on the control surface based upon the given variables in columns 1510. In some embodiments, the manufacturer of the controller or the author of the database determines a single watercraft design or a smaller set of watercraft designs, essentially fixing one or more of the variables described in columns 1510.
Column 1530 comprises heuristic data determined from use of a boat. In many embodiments, after the database is installed on a boat, the controller of the boat begins to populate column 1530 based upon actual use of the boat, customizing the database to the boat operator and the locations in which the boat is typically used. In some embodiments, the data is continually updated as different data is identified. In further embodiments, the heuristic data is repeatedly averaged with newer data.
The control surface adjustment formulas 1550 provide a number of formulas for determining an adjustment for the position of the control surface with respect to the propeller. Other embodiments may comprise one or more formulas similar to one or more of these formulas or another formula. In particular, control surface adjustment formulas comprise an interpolator column. The interpolator column comprises data that provides typical adjustments based upon the net thrust and the angle of the control surface with respect to the thrust generated by the propeller. If the data for the specific angle and/or net thrust is not available, the controller may interpolate the data to determine an adjustment. In many of these embodiments, the controller may comprise a module to monitor the result of the adjustment and dynamically adjust or fine-tune the angle of the control surface with respect to the propeller to attain the desired result. For instance, the module may monitor rotational or angular acceleration and/or velocity, linear acceleration and/or velocity, speed, and the like to compare against the thrust to adjust the angle and/or position of the control surface.
The second column of the control surface adjustment formulas 1550 provides one or more formulas as an alternative method to determine the adjustment. For example, different formulas may be available for different net thrusts, angles of the control surface, hull designs, weights, and/or other available information.
The third column of the control surface adjustment formulas 1550 provides one or more curve fitting formulas that may determine the adjustment for the position of the control surface based upon the heuristic data for the control surface pressure in column 1530 of
Other embodiments may comprise more or less information, which may affect the accuracy of the initial determination for the angle adjustment. For example, one embodiment may also comprise an indication of the weight distribution of the watercraft.
Referring now to
If the boat operator shifts the boat into reverse, reversing the direction of the propeller (element 1610), the spring-loaded hinge may maintain a force on the control surface to impede the draw of water into the propeller to attenuate the reverse thrust generated by the propeller (element 1640). For instance, the hinge may be adapted to allow substantially little movement by the control surface toward the propeller to prevent the control surface from damaging the propeller and vice versa. The hinge should be capable of applying a force that is at least as great as the reverse thrust.
On the other hand, if the propeller is generating a forward thrust rather than a reverse thrust (element 1610), a force may be applied to the control surface to reflect at least a component of the thrust back toward the propeller. In some embodiments, the force may be applied via a spring. In further embodiments, the force may be applied via an arm such as an adjustable length arm. If the hinge is spring-loaded (element 1625), the spring may compress in response to an increase in forward thrust, allowing the control surface to transition into a new position, which is based upon the loading characteristic of the spring and the magnitude of the thrust (element 1630).
In several embodiments, the length of one or more adjustable arms and/or the tension on one or more cables may determine the position of the control surface and the hinge may not be spring-loaded (element 1625). In such embodiments, the boat operator may manually with or without powered assist adjust the length of the arm(s) or tension on the cable(s), or a controller may implement the changes for the boat operator. Force may be applied to the control surface as a result, to modify the position of the control surface and maintain the control surface in the new position (element 1635).
In other embodiments, the hinge may be spring-load and the adjustable arm or cable may compliment the force of the spring to determine whether to move the control surface. For instance, a cable may pull the control surface, reducing the net force applied to the control surface to counteract the thrust. In such situations, the control surface may move in a linear or angular motion away from the thrust. On the other hand, an arm may be lengthened to apply force that adds to the force applied to the spring to move the control surface toward the propeller. In such situations, the control surface may either move closer to the propeller or maintain its current position.
Referring now to
In response to the indication from a boat operator to adjust a position of a control surface based upon identified criteria, the controller determines the current position of the control surface (element 1715) and then determines an adjustment to the position of the control surface, if any, to maintain the criteria. Determining the current position of the control surface may comprise reading and interpreting indications of sensors. For instance, rotatable joints may comprise a sensor that provides an indication of the extent of the rotation and arms having adjustable lengths may couple with sensors adapted to provide the length of the arm. In further embodiments, the sensors provide relative angles or distances, or changes in angles and distances. In such embodiments, the controller may interpret the data to track the current position of the control surface. In some of these embodiments, the controller may calibrate the position of the control surface by allowing the force of one or more springs to return the control surface to a known position and determining correction factors for the readings from the sensors.
Based upon the current position of control surface, the controller may determine an adjustment for the position of the control surface. For example, if the boat operator turns to boat to port and the controller is attempting to maintain the port-to-starboard angle of the boat substantially parallel to the water line, the controller may modify the angle of the control surface with respect to the thrust to reflect a component of the thrust to port to counteract the tendency of the boat roll toward the port during the turn.
In some embodiments, the controller may comprise heuristic data from a similar turn at a similar speed that indicates the new position for the control surface or an adjustment for the position of the control surface. If the heuristic data is available (element 1725), the data is read (element 1750) and the controller modifies the position of the control surface in accordance with the new position.
If pressure sensor data is available via a sensor for the control surface (element 1730), further embodiments may read the pressure data to determine the current components of thrust redirected by the control surface and determine the desired components of redirected thrust (element 1732). Then, the controller may modify the angle of the control surface with respect to the propeller or the distance of the control surface from the propeller based upon the desired components of thrust (element 1745).
If no pressure sensor data is available, the controller may read and/or interpolate data from heuristic data that indicates pressure on the control surface under the similar conditions such as the speed, the turning radius of the boat, the angles of the boat port-to-starboard and/or bow-to-stern, and/or the like. If the heuristic data is available (element 1735), the controller may read the pressure data (element 1737) and determine the new position of the control surface based upon the criteria.
If no pressure data is available, the controller may calculate a theoretical pressure on the control surface (element 1740) based upon formulas or logic provided to the controller to determine components of redirected thrust. The controller may then determine the new position of the control surface to provide the desired components of redirected thrust (element 1745).
The controller may determine the change in the current position based upon the current components of redirected thrust modify the position of the control surface accordingly (element 1755). If the criterion indicated by the boat operator represents a request for repeated or periodic adjustments, the controller may continue to monitor whether the position of the control surface should be adjusted and repeat the above elements as necessary.
One embodiment of the invention is implemented as a program product for use with a computer system such as, for example, the system 100 shown in
In general, the routines executed to implement the embodiments of the invention, may be part of an operating system or a specific application, component, program, module, object, or sequence of instructions. The computer program of the present invention typically is comprised of a multitude of instructions that will be translated by the native computer into a machine-readable format and hence executable instructions. Also, programs are comprised of variables and data structures that either reside locally to the program or are found in memory or on storage devices. In addition, various programs described hereinafter may be identified based upon the application for which they are implemented in a specific embodiment of the invention. However, it should be appreciated that any particular program nomenclature that follows is used merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and/or implied by such nomenclature.
It will be apparent to those skilled in the art having the benefit of this disclosure that the present invention contemplates redirecting a thrust generated by a propeller via a control surface for a watercraft to provide greater control over the thrust to the boat operator. It is understood that the form of the invention shown and described in the detailed description and the drawings are to be taken merely as examples. It is intended that the following claims be interpreted broadly to embrace all the variations, and, logical combinations of the example embodiments disclosed.
Pursuant to 35 USC §119(e), this application claims priority to and benefit of U.S. Provisional Patent Application Ser. No. 60/609,717, filed Sep. 14, 2004.
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| Number | Date | Country | |
|---|---|---|---|
| 20060054067 A1 | Mar 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60609717 | Sep 2004 | US |
