Surf wake forming systems and methods with primary and secondary subtabs

Abstract

A wakeboat has a hull, the hull forming a wake when moving forward in the water, with a left quiet region and a right quiet region in the wake. The hull may exhibit rotation around its yaw axis which affects the quiet regions in the wake. Yaw rotation may be measured via one or more sensors. Yaw measurement may be used to control the hull and quiet regions. A trim tab is supported by the hull at the stern of the hull. The trim tab comprises a primary subtab and a secondary subtab. One or more actuators may be optionally included to reposition the trim tab more into, or more out of, the water to create a surf left and/or surf right configuration. Other systems and methods are also provided.

Claims

1. A system for forming asymmetric surf wakes behind a wakeboat including a hull having a port side, a starboard side, an inside, an outside, a stern, a roll axis, a pitch axis, and a yaw axis, the hull being configured to float in water with a waterline on the outside of the hull, the hull when moving forward in the water creating a wake with a left quiet region and a right quiet region, the system comprising: a yaw detector configured to measure the rotation of the hull about its yaw axis; a primary left trim tab pivotally supported by the hull proximate the port side of the stern for rotation about a first tab axis that is substantially parallel with the waterline when the hull is at rest in the water; a primary left actuator mounted between the hull and the primary left trim tab, and configured to rotate the primary left trim tab around the first tab axis of the primary left trim tab from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull, a secondary left trim tab pivotally supported by the primary left trim tab for rotation about a second tab axis that is non-parallel to the first tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a starboard direction to enlarge the right quiet region; a secondary left actuator mounted between the primary left trim tab and the secondary left trim tab, and configured to rotate the secondary left trim tab to enlarge the right quiet region and create at least one surf right configuration; a primary right trim tab pivotally supported by the hull proximate the starboard side of the stern for rotation about a third tab axis that is substantially parallel with the waterline when the hull is at rest in the water; a primary right actuator mounted between the hull and the primary right trim tab, and configured to rotate the primary right trim tab around the third tab axis from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull; a secondary right trim tab pivotally supported by the primary right trim tab for rotation about a fourth tab axis that is non-parallel to the third tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a port direction to enlarge the left quiet region; and a secondary right actuator mounted between the primary right trim tab and the secondary right trim tab, and configured to rotate the secondary right trim tab to enlarge the left quiet region and create at least one surf left configuration.

2. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 wherein the yaw detector comprises a first accelerometer configured to selectively measure acceleration of the hull along its roll axis and a second accelerometer configured to selectively measure acceleration of the hull along its pitch axis.

3. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 wherein the yaw detector comprises a fin-type sensor rotatably mounted to the outside of the hull and configured to align itself with the direction of the passing water.

4. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 wherein the yaw detector comprises a pressure transducer configured to measure the pressure of the water on the outside of the hull.

5. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 wherein the yaw detector is configured to measure forces acting upon at least one of the trim tabs.

6. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 and further comprising a rudder pivotally supported by the hull, wherein the yaw detector is configured to measure forces acting upon the rudder.

7. The system for forming asymmetric surf wakes behind a wakeboat of claim 1 wherein the yaw detector comprises a Global Positioning System receiver supported by the hull and configured to selectively generate measurements of heading and at least one of bearing, course, and track.

8. A system for forming asymmetric surf wakes behind a wakeboat including a hull having a port side, a starboard side, an inside, an outside, a stern, a roll axis, a pitch axis, and a yaw axis, the hull being configured to float in water with a waterline on the outside of the hull, the hull when moving forward in the water creating a wake with a left quiet region and a right quiet region, the system comprising: a yaw detector configured to measure the rotation of the hull about its yaw axis; a primary left trim tab pivotally supported by the hull proximate the port side of the stern for rotation about a first tab axis that is substantially parallel with the waterline when the hull is at rest in the water; a primary left actuator mounted between the hull and the primary left trim tab, and configured to rotate the primary left trim tab around the first tab axis of the primary left trim tab from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull; a secondary left trim tab pivotally supported by the primary left trim tab for rotation about a second tab axis that is non-parallel to the first tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a starboard direction to enlarge the right quiet region; a secondary left actuator mounted between the primary left trim tab and the secondary left trim tab, and configured to rotate the secondary left trim tab to enlarge the right quiet region and create at least one surf right configuration; a primary right trim tab pivotally supported by the hull proximate the starboard side of the stern for rotation about a third tab axis that is substantially parallel with the waterline when the hull is at rest in the water; a primary right actuator mounted between the hull and the primary right trim tab, and configured to rotate the primary right trim tab around the third tab axis from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull; a secondary right trim tab pivotally supported by the primary right trim tab for rotation about a fourth tab axis that is non-parallel to the third tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a port direction to enlarge the left quiet region; a secondary right actuator mounted between the primary right trim tab and the secondary right trim tab, and configured to rotate the secondary right trim tab to enlarge the left quiet region and create at least one surf left configuration; and a controller with an actuator interface, the controller in selective communication with the yaw detector, the controller in further selective communication with at least one of the primary left actuator, the secondary left actuator, the primary right actuator, and the secondary right actuator.

9. The system for forming asymmetric surf wakes behind a wakeboat of claim 8 wherein the controller selectively operates at least one of the actuators in response to measurements from the yaw detector.

10. The system for forming asymmetric surf wakes behind a wakeboat of claim 9 wherein the controller selectively operates at least one of the actuators to modify the rotation of the hull about its yaw axis in response to measurements from the yaw detector.

11. The system for forming asymmetric surf wakes behind a wakeboat of claim 9 wherein the controller selectively operates at least one of the actuators to modify the left quiet region in response to measurements from the yaw detector.

12. The system for forming asymmetric surf wakes behind a wakeboat of claim 9 wherein the controller selectively operates at least one of the actuators to modify the right quiet region in response to measurements from the yaw detector.

13. A method of manufacturing a wakeboat including a hull having a port side, a starboard side, an inside, an outside, a stern, a roll axis, a pitch axis, and a yaw axis, the hull being configured to float in water with a waterline on the outside of the hull, the hull when moving forward in the water creating a wake with a left quiet region and a right quiet region, the method comprising: providing a yaw detector configured to measure the rotation of the hull about its yaw axis; pivotally supporting a primary left trim tab by the hull proximate the port side of the stern for rotation about a first tab axis that is substantially parallel with the waterline when the hull is at rest in the water; mounting a primary left actuator between the hull and the primary left trim tab, and configured to rotate the primary left trim tab around the first tab axis of the primary left trim tab from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull; pivotally supporting a secondary left trim tab by the primary left trim tab for rotation about a second tab axis that is non-parallel to the first tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a starboard direction to enlarge the right quiet region; mounting a secondary left actuator between the primary left trim tab and the secondary left trim tab, and configured to rotate the secondary left trim tab to enlarge the right quiet region and create at least one surf right configuration; pivotally supporting a primary right trim tab pivotally by the hull proximate the starboard side of the stern for rotation about a third tab axis that is substantially parallel with the waterline when the hull is at rest in the water; mounting a primary right actuator between the hull and the primary right trim tab, and configured to rotate the primary right trim tab around the third tab axis from a position having decreased interaction with the water passing beneath the hull to a position having increased interaction with the water passing beneath the hull; pivotally supporting a secondary right trim tab by the primary right trim tab for rotation about a fourth tab axis that is non-parallel to the third tab axis, and configured to rotate from a position having decreased interaction with the water passing beneath the hull to a position that rotates the stern of the hull in a port direction to enlarge the left quiet region; mounting a secondary right actuator between the primary right trim tab and the secondary right trim tab, and configured to rotate the secondary right trim tab to enlarge the left quiet region and create at least one surf left configuration; and providing a controller in selective communication with the yaw detector, the controller in further selective communication with at least one of the primary left actuator, the secondary left actuator, the primary right actuator, and the secondary right actuator.

14. The method of claim 13 wherein the controller selectively operates at least one of the actuators in response to measurements from the yaw detector.

15. The method of claim 14 wherein the controller selectively operates at least one of the actuators to modify the rotation of the hull about its yaw axis in response to measurements from the yaw detector.

16. The method of claim 14 wherein the controller selectively operates at least one of the actuators to modify the left quiet region in response to measurements from the yaw detector.

17. The method of claim 14 wherein the controller selectively operates at least one of the actuators to modify the right quiet region in response to measurements from the yaw detector.

18. The method of claim 14 wherein the yaw detector is configured to measure forces induced by water acting upon at least one of the trim tabs.

19. The method of claim 14 wherein the yaw detector is configured to measure forces induced by water acting upon at least one of the primary and secondary left trim tabs and at least one of the primary and secondary right trim tabs.

20. The method of claim 14 further comprising the hull pivotally supporting a rudder, wherein the yaw detector is configured to measure forces acting upon the rudder.

Description

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS

(1) FIG. 1 illustrates a wakeboat according to some embodiments of the disclosure.

(2) FIG. 2 shows a top view of a trim tab according to some embodiments of the disclosure.

(3) FIG. 3 shows a bottom view and dimensions of a trim tab according to some embodiments of the disclosure.

(4) FIG. 4 shows a side view of a trim tab according to some embodiments of the disclosure.

(5) FIG. 5 shows a rear view of a trim tab according to some embodiments of the disclosure.

(6) FIG. 6 shows a rear view of a trim tab according to some embodiments of the disclosure.

(7) FIG. 7A illustrates force acting on a hull, centered on a center of mass, according to some embodiments of the disclosure.

(8) FIG. 7B illustrates force acting on a hull, offset from a center of mass, according to some embodiments of the disclosure.

(9) FIG. 8 shows an under-hull view of a trim tab according to some embodiments of the disclosure.

(10) FIG. 9A shows a top view of a boat equipped with one embodiment of the disclosure, without induced yaw rotation.

(11) FIG. 9B shows a top view of a boat with induced yaw rotation via port deployment, according to some embodiments.

(12) FIG. 10A shows a top view of a boat equipped with one embodiment of the disclosure, without induced yaw rotation.

(13) FIG. 10B shows a top view of a boat with induced yaw rotation via starboard deployment, according to some embodiments.

(14) FIG. 11 shows a controller and associated subsystems according to some embodiments of the disclosure.

(15) FIG. 12 shows a display with touch-sensitive regions according to some embodiments of the disclosure.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

(16) This disclosure is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws to promote the progress of science and useful arts (Article 1, Section 8).

(17) Attention is directed towards the following patents, all of which are incorporated herein by reference: U.S. Pat. No. 8,798,825 issued to Hartman on Aug. 5, 2014; U.S. Pat. No. 9,828,075 issued to Hartman on Nov. 28, 2017; and U.S. Pat. No. 9,689,395 issued to Hartman on Jun. 26, 2017, all of which are assigned to Skier's Choice of Maryville Tenn. Attention is also directed towards U.S. Patent Application Publication No. 2007/0036738 to Hartman, Published Feb. 9, 2017, and to U.S. patent application Ser. No. 15/824,787, filed Nov. 28, 2017, both of which are assigned to Skier's Choice of Maryville Tenn., and both of which are incorporated herein by reference. Attention is also directed to commonly assigned U.S. patent application Ser. No. 16/139,847, filed Sep. 24, 2018, naming Hartman et al. as inventors, and incorporated herein by reference.

(18) The assemblies and methods of the present disclosure will be described with reference to FIGS. 1-10.

(19) As discussed in the Background section above, a plurality of traditional horizontally oriented trim tabs can impart tilt/roll/list to the hull of a wakeboat via dissimilar angles of deployment. Such rotation causes the hull to have an asymmetric relationship to the water, thus forming an asymmetric wake behind the moving hull.

(20) The present disclosure improves upon a traditional horizontally oriented trim tab by dividing the trim tab into at least two parts, or subtabs. For brevity and ease of understanding this description will refer to a trim tab comprising two subtabs, but it is to be understood that other embodiments can comprise more than two subtabs depending upon the specifics of the application.

(21) In some embodiments of the present disclosure, the primary function of one subtab is to cause the hull to rotate around its roll (also known as the longitudinal, Y, tilt, or list) axis. Meanwhile, the primary function of another subtab is to cause the hull to rotate around its yaw (also known as the vertical or Z) axisthe axis which is oriented primarily vertically, orthogonal to the roll and pitch axes. By imparting yaw rotation to the hull, the hull itself changes the formation of its own wake as it moves forward through the water.

(22) FIG. 1 shows a boat 9 in accordance with various embodiments. The boat includes a hull 100 with a left (or port) trim tab 110 and a right (or starboard) trim tab 120 installed at or near transom 150 (rear) of the hull. Some embodiments employ controller 130 to selectively send control signals via connection 160 and connection 170, respectively, to reposition trim tabs 110 and/or 120 as described below. Other embodiments use discrete, user-operated switches to reposition trim tabs 110 and/or 120.

(23) FIG. 2 is a closeup view of the upper surface of port trim tab 110 from FIG. 1. In some embodiments, each trim tab has two subtabs, hereinafter referred to individually as main tab and yaw tab and collectively as trim tab. Some embodiments locate the yaw tab at different positions relative to the main tab as suitable for the specifics of the application. The example figures herein illustrate the yaw tabs toward the centerline of the hull but it is to be understood that this does not restrict the yaw tabs from being located elsewhere with respect to the main tabs and/or the hull.

(24) Continuing with FIG. 2, in some embodiments main tab 210 is pivotally connected to hull 100 of FIG. 1 via hinge 220. Hinge 220 may be a traditional hinge, a living hinge of flexible material, or another pivotable attachment device suited to the specifics of the application.

(25) The angle of main tab 210 with respect to hull 100 is adjustable, in operation, via main tab actuator 230. Actuator 230 converts a control signal from controller 130 to a physical force that repositions main tab 210. The control signal may be electrical, mechanical, hydraulic, pneumatic, or another signal type suited to the specifics of the application. The resulting physical force from actuator 230 may be based on electromagnetics, mechanics, hydraulics, pneumatics, or another principle suited to the specifics of the application. In some embodiments actuator 230 is mounted between transom 150 and main tab 210 as shown, but other mounting positions and arrangements may be used as suited to the specifics of the application.

(26) Continuing with FIG. 2, in some embodiments yaw tab 240 is pivotally connected to main tab 210 via yaw tab hinge 250. Hinge 250 may be a traditional hinge, a living hinge of flexible material, or another pivotable attachment technique suited to the specifics of the application.

(27) The angle of yaw tab 240 with respect to main tab 210 is adjustable via yaw tab actuator 260, in operation. Actuator 260 converts a control signal from controller 130 to a physical movement that repositions yaw tab 240. The control signal may be electrical, mechanical, hydraulic, pneumatic, or another signal type suited to the specifics of the application. The resulting physical movement from actuator 260 may be based on electromagnetics, mechanics, hydraulics, pneumatics, or another principle suited to the specifics of the application. In some embodiments actuator 260 is mounted on the top surface of main tab 210 as shown, but other mounting positions and arrangements may be used as suited to the specifics of the application. For example, in some embodiments actuator 260 is mounted between the transom and yaw tab 240, with controller 130 selectively coordinating the operation of actuator 230 and actuator 260.

(28) In some embodiments, actuator 260 can be a manual adjustment relying on direct operator input instead of a control signal from controller 130. This manual adjustment may be effected in any applicable manner including but not limited to a threaded shaft in place of actuator 260, a hinge 250 that incorporates a positional lock, a block or wedge that establishes the desired angle between yaw tab 240 and main tab 210, or another manner suited to the specifics of the application.

(29) An example of an electrically powered actuator that could be employed for actuator 230 and actuator 260 is the Lenco 15054-001 (Lenco Marine Inc., 4700 SE Municipal Court, Stuart Fla. 34997). Another example of an electrically powered actuator that could be employed for actuator 230 and 260 is the Bennett BEA2000 (Bennett Marine Inc., 550 Jim Moran Boulevard, Deerfield Beach Fla. 33442). An example of a hydraulically powered actuator that could be employed for actuator 230 and actuator 260 is the Bennett A1101A (Bennett Marine Inc., 550 Jim Moran Boulevard, Deerfield Beach Fla. 33442). For a given embodiment the stroke length, mounting brackets, and other options for the actuator(s) may be selected based on the specifics of that application.

(30) FIG. 3 is a closeup view of the lower surface of port trim tab 110 showing the dimensions of main tab 210 and yaw tab 240 in some embodiments of the present disclosure. These dimensions, and the relative angles of the edges, may be altered in some embodiments to achieve desired performance. For example, main tab 210 and/or yaw tab 240 may be increased in size so their increased surface areas yield greater forces when used on larger hulls. Conversely, smaller hulls may obtain suitable performance from tabs that are scaled down appropriately.

(31) In some embodiments the sizes, shapes, range of deployment angles, and dimensions of main tab 210 and yaw tab 240 may be altered. This may be useful when the absolute, relative, or ratiometric roll axis force and/or yaw axis force are to be adjusted for the specifics of the application, as will be discussed in more detail below.

(32) In some embodiments, such as that illustrated in FIG. 3, the angle of mounting of yaw tab 240 to main tab 210 is between 35 and 55 degrees. In a more particular embodiment, the angle between the yaw tab 240 and main tab 210 is approximately 45 degrees. Among other effects, this angle balances yaw effect versus hydrodynamic drag, both of which are caused by extending yaw tab 240 into the moving water under the hull of the boat. In some embodiments, this angle is changed to obtain a different relationship between yaw and drag as is suitable for the specifics of the application. Amount of deflection may be more significant than the angle of deflection in creating a desired yaw force, in some embodiments.

(33) Depending upon the specifics of the application, some embodiments may locate yaw tab 240 on the opposite (outboard) side of main tab 210. In such embodiments the relationship of yaw tab side to direction of yaw is reversed, e.g. deployment of an outboard port side yaw tab 240 will impart rotation around the yaw axis of hull 100 toward its port side, instead of the starboard side as shown in earlier examples herein which illustrate an inboard-mounted yaw tab 240. This may be advantageous when, for example, a specific hull design benefits from having an inverse relationship between roll and yaw adjustments from that described above. The non-parallel alignment of hinge 220 and hinge 250 is what allows yaw tab 240 to impart yaw rotation to hull 100; the specific angle of that alignment, and the location of yaw tab 240 in relation to main tab 210, may be changed as suitable for the specifics of hull 100 and its intended application.

(34) FIG. 4 is a side view of one embodiment having hull 100 with a port trim tab 110. Many of the elements shown in FIG. 3 are again labeled in FIG. 4 for clarity. Main tab 210 and yaw tab 240 are in their retracted positions, such that their bottom planar surfaces are angled generally equal to or above the bottom planar surface of hull 100. In this position, main tab 210 and yaw tab 240 have minimal interaction with the water, and therefore experience minimal forces from the water moving under them as the hull proceeds forward.

(35) In the embodiment of the present disclosure shown in FIG. 4, main tab 210 and yaw tab 240 (obscured in this view) are linearly aligned when the trim tab is retracted. In other embodiments, different angles of retraction may be used as suitable for the specifics of the application.

(36) FIG. 5 is a rear view of hull 100 with port trim tab 110, still in its retracted position. The planar alignment of main tab 210 and yaw tab 240 in this embodiment are clearly distinguishable in this perspective, as is the equal-or-greater-than angular relationship of trim tab 110 to the bottom planar surface of hull 100.

(37) To impart yaw to the hull, some embodiments deploy the main and trim tabs below the bottom planar surface of the hull. FIG. 6 is a rear view of hull 100 with main tab 210 and yaw tab 240 deployed. In this embodiment, axis of main tab hinge 220 is substantially parallel with transom 150 of hull 100. This causes main tab 210 to remain substantially parallel with transom 150 of hull 100 as it translates through the range of its rotation. Main tab 210 may instead be mounted with its pivot axis substantially parallel to the waterline when the hull is at rest in the water, or another orientation that directs a majority of the lifting force experienced by main tab 210 to imparting rotation of hull 100 around its lateral/pitch axis.

(38) In contrast, the effect of yaw tab hinge 250 being at an angle relative to main tab hinge 220 (and thus to transom 150 of hull 100) is now evident. As actuator 260 imparts downward movement to yaw tab 240, the axis of yaw tab hinge 250 causes the planar alignment of yaw tab 240 to be non-parallel with respect to transom 150 of hull 100 as it translates through the range of its rotation.

(39) Continuing with FIG. 6, as hull 100 moves forward water impinges upon the leading face of yaw tab 240. The effect is like a rudder: Yaw tab 240 will experience a sideways force toward leading edge 610 and away from trailing edge 620. In this embodiment, deployment of yaw tab 240 on a port trim tab when hull 100 is moving forward through water will impart a sideways force against yaw tab 240 toward the opposite (starboard) side of hull 100.

(40) Yaw tab 240 conveys that starboard force through yaw tab hinge 250 to main tab 210. Main tab 210 then conveys the starboard force through main hinge 220 to transom 150. Finally, hull 100 reacts to the starboard force at transom 150 by shifting its transom to starboard (right).

(41) Were this starboard force applied to hull 100 in line with its center of mass, hull 100 would shift to the right without rotation. However, since the starboard force is applied at one end of hull 100, that endthe stern, where transom 150 is located and the force is being appliedexperiences the majority of the starboard force and the imbalance of force along the length of hull 100 causes it to react unevenly along its length. The result is that hull 100 rotates rather than shifts sideways.

(42) For better understanding of this effect, it is illustrated in FIGS. 7A and 7B (this discussion, FIG. 7A, and FIG. 7B are simplified for clarity). Referring to FIG. 7A, if starboard force 710 were applied to hull 100 in line with the center of mass 720 of hull 100, hull 100 would experience equal force fore and aft of its center of mass. With equal forces on both sides of its center of mass, hull 100 would not experience a rotative force (no torque) and its reaction to starboard force 710 would be to shift sideways in the water toward its starboard side in proportion to the magnitude of starboard force 710.

(43) In contrast, FIG. 7B illustrates the behavior caused by the illustrated embodiment of the present disclosure. Starboard force 730 is applied to hull 100 at or near its stern 750, well aft of the center of mass 720 of hull 100. The forces on the two sides of center of mass 720 are now significantly unequal. The lever arm represented by distance 740 (the distance from the center of mass 720 to the stern 750 of hull 100) converts starboard force 730 to a rotative torque acting on stern 750. Meanwhile, since substantially all of starboard force 730 is applied at or near stern 750, virtually no component of starboard force 730 acts upon hull 100 forward of center of mass 720. With torque acting on stern 750, and little to no opposing component acting forward of center of mass 720, the result is that, in this example, hull 100 rotates counter-clockwise as viewed from above. Stated differently, stern 750 moves in the direction of leading edge 610 of yaw tab 240 and opposite the direction of trailing edge 620 of yaw tab 240.

(44) To better visualize this effect in the context of hull 100 in water, FIG. 8 shows a water's eye view of hull 100 equipped with one embodiment of the present disclosure, where port trim tab 110 has been deployed. The perspective is from the bow (front) of hull 100, looking toward stern 750, under the hull as if hull 100 is moving forward through the water.

(45) Proceeding with FIG. 8, main tab 210 and yaw tab 240 of this embodiment have been deployed down into the water. Main tab 210 remains parallel to transom 150 due to hinge 220 (not visible in FIG. 8) as explained above. Yaw tab 240 is non-parallel to transom 150 due to hinge 250, also as explained above. As water passes under hull 100 and impinges upon deployed yaw tab 240, yaw tab 240 experiences a force toward leading edge 610 which, in this embodiment, is toward the starboard side of hull 100 (to the left in FIG. 8). This force is conveyed from yaw tab 240 to hull 100 as described above, resulting in the stern of hull 100 moving toward its starboard side and hull 100 rotating around its center of mass, also as described above.

(46) In short, in this example embodiment, deployment of port yaw tab 240 causes hull 100 to rotate around its yaw axis, with its stern (rear) rotating to starboard and its bow (front) rotating to port.

(47) To enhance clarity and understanding, FIGS. 9A and 9B are top-down photographs of this embodiment being demonstrated on an actual boat in water. (The boat interiors have been obscured to preserve the privacy of the individuals on board.) FIG. 9A shows the boat of FIG. 8 proceeding forward in water with both of this embodiment's trim tabs retracted. The hull's heading 905 (the direction it is pointing) and its course 930 (the direction it is moving) are approximately collinear. Expressed in 3D coordinate axis terms, there is minimal rotation of the hull on its yaw axis. As a result, the hull has a generally symmetrical relationship with the water.

(48) As noted earlier, a generally symmetrical hull relationship TO the water yields a generally symmetrical wake behind the hull IN the water. And so it is in FIG. 9A: Port disturbance 910 and starboard disturbance 920 are generally symmetrical, with the white froth of their disturbances generating a region of convergence behind the hull of the boat that is also generally symmetrical. There is a small, generally quiet region 960 of water behind the port (left) side of the hull and a small, generally quiet region 970 of water behind the starboard (right) side of the hull.

(49) FIG. 9B reveals the effect of this embodiment of the present disclosure when its port main tab and port yaw tab are deployed down into the water. As the overlay lines of FIG. 9B make clear, the hull's heading 905 (the direction it is pointing, which is also its longitudinal axis) and course 930 (the direction it is moving) have diverged and now differ by a significant amount. Expressed more simply, the hull has been rotated on its yaw axis by the processes described in the preceding paragraphs.

(50) Naturally, a boat hull rotates when changing direction (turning). Therefore it is important to note in FIG. 9B that the hull's course is still a straight line. The hull has not changed the direction it is moving; this embodiment of the present disclosure has rotated the hull around its yaw axis (its longitudinal axis points along line 905) while the hull continues to travel forward in a straight line (along line 930).

(51) Comparing FIG. 9A with FIG. 9B, the effect of this embodiment on the wake behind the hull is immediately apparent. In FIG. 9A, port disturbance 910 and starboard disturbance 920 coming off the two sides of the hull are generally symmetrical because this embodiment's main tab and yaw tab are not significantly engaged with the water. But in FIG. 9B, with this embodiment's port main tab and port yaw tab deployed and thus the stern (rear) of the hull rotated around its yaw axis such that its stern is rotated to the right (starboard), port disturbance 910 and starboard disturbance 920 are now noticeably asymmetrical, as desired. Likewise, the region of reconvergence behind the hull of the boat is also noticeably asymmetrical: Almost all of the froth and disturbance has been shifted to the left (port) side, leaving the starboard (right) side quiet and clear, again as desired.

(52) This asymmetry is caused by the hull yaw angle. Where in FIG. 9A the port and starboard trailing edges of the hull had a generally symmetrical relationship to the direction of hull movement, in FIG. 9B the yaw angle of the hull has given the port and starboard trailing edges of the hull an asymmetrical relationship to the direction of hull movement. As a result, port disturbance 910 and starboard disturbance 920 are asymmetrical, which in turn relocates region of convergence toward the port (left) side as compared with its original, unyawed-hull position in FIG. 9A.

(53) The effect on the wake behind the hull is clearly visible in FIG. 9B: Quiet region 970 behind the right rear of the hull is noticeably longer and wider than in FIG. 9A. Indeed, it extends so far behind the hull of the wakeboat that it exceeds the boundaries of FIG. 9B's top view.

(54) In this embodiment, the opposite yaw rotation (not shown in FIG. 9A and FIG. 9B) is obtained by deployment of a starboard yaw tab. FIG. 10A and FIG. 10B illustrate this opposite-side effect for this embodiment. The preceding discussions for FIG. 9A and FIG. 9B apply to FIGS. 10A and 10B with the left/port and right/starboard directions reversed. With FIG. 10B's starboard deployment, it is quiet region 960 which is noticeably longer and wider than in FIG. 10A.

(55) Certain embodiments of the present disclosure, including that shown in FIG. 9B and FIG. 10B, achieve their improved asymmetric wake not by delaying the convergence of the wake behind the hull of the boat, but by relocating the port and starboard disturbances from their traditional locations relative to the longitudinal axis of the hull.

(56) Referring again to FIGS. 10 through 12 of U.S. Pat. No. 3,200,782 to Walden, and FIGS. 13a and 13b of U.S. Pat. No. 9,260,161 to Gasper, both of these references illustrate using vertically oriented trim tab elements to widen the flow of water past the transom. In the words of Gasper, water from the two sides is disrupted . . . causing it to converge . . . beyond its natural intersection (see FIGS. 13A, 13B, and 13C) and delaying convergence . . . to a point further from the transom (see Col. 12, Lines 33-34).

(57) By way of differentiation, some embodiments of the present disclosure do not rely upon widening the flow of water past the transom nor delaying convergence to a point further from the transom. As shown in FIGS. 9B and 10B, when certain embodiments of the present disclosure induce yaw rotation in the hull, the convergence (where port disturbance 910 and starboard disturbance 920 first meet) occurs at the same or even less distance behind the transom of the hull as in FIGS. 9A and 10A when no yaw rotation was induced. Instead, such embodiments use the vertical sides of the hull to render port disturbance 910 and starboard disturbance 920 asymmetric, which then yields the desired asymmetric wake behind the hull of the boat.

(58) The deployment of this embodiment on the port (left) side of the hull causes starboard disturbance 920 to relocate from its traditional location on the starboard (right) side of longitudinal axis 905 in FIG. 9A, to the port (left) side of longitudinal axis 905 in FIG. 9B. The convergencethe intersectionof the two disturbances is not delayed, and still occurs closely behind the transom. But the direction of starboard disturbance 920 has been shifted significantly, moving the froth and churn of the water which truncated quiet region 970 in FIG. 9A to the other side of longitudinal axis 905 where it no longer interferes with quiet region 970. The result is clearly visible in the increased width and especially length of quiet region 970 in FIG. 9B.

(59) The same effect occurs on the port (left) side of the wake when this embodiment is deployed on the starboard (right) side of the hull. Returning again to FIG. 10B, it is now port disturbance 910 whose froth and churn have been moved to the opposite side of longitudinal axis 905, eliminating the interference that narrowed and shortened quiet region 960 in FIG. 10A.

(60) As the foregoing description and figures explain, various embodiments of the present disclosure can deliver desirable asymmetric wakes using various techniques. This array of options gives the present disclosure increased flexibility, allowing its operation to be implemented in different ways for different hulls depending upon the preference of the boat engineer(s).

(61) Some embodiments of the present disclosure use fixed angles of retraction and employment for the main tab(s) and/or yaw tab(s). Other embodiments employ multiple, discrete angles of deployment. Still others offer a continuum between full retraction and full deployment. A combination of such deployment options may be used, with different options on each of the subtabs in an overall trim tab. As with size, shape, and other physical characteristics noted earlier, the present system has a broad spectrum of applicability and the specifics of each embodiment may be obtained through pure engineering, empirical analysis, or both.

(62) In some embodiments, the main tab 210 and yaw tab 240 of the dimensions shown in FIG. 3 may be employed on a Mojo Pro model boat manufactured by Skier's Choice of Maryville, Tenn. The Mojo Pro is a twenty three foot boat with a dry weight of 4,400 lbs. The boat has a ballast system that adds up to 3,000 lbs of additional weight to the boat. Further, this model boat has additional capacity for 2,500 lbs of passengers or gear.

(63) In some embodiments, the main tabs are selected to impart sufficient roll to the hull and the yaw tabs are selected to impart sufficient yaw to the hull. A sufficiently large displacement (e.g. a boat loaded with ballast, passengers, and gear) may achieve the desired wake asymmetry with less reliance on the size and shape of the main and yaw tabs. With less displacement (e.g. the boat is not fully loaded) the positions of the main tabs and yaw tabs may be adjusted to optimize the wake asymmetry.

(64) As the starboard and port main tabs and yaw tabs are deployed down into the water they not only roll or yaw the boat, but they also create lift. Lift acts against the weight, and thus the displacement, of the boat. In some embodiments, operation begins with filling the ballast system to 100% and setting the starboard and port main tabs to 0% deflection. Then, one of the main plates is moved down slowly until sufficient hull roll is achieved to clean up the wake on the desired side.

(65) In some embodiments, operation continues by adjusting the yaw tab until its induced hull yaw creates a surfable wake by optimizing the tradeoff between displacement (of the hull) and lift (from the main and yaw tabs).

(66) In some embodiments, a center trim tab (not shown) is provided between starboard trim tab 120 and port trim tab 110. This center trim tab may be operated independently of, or in synchronization with, starboard trim tab 120 and port trim tab 110 as conditions warrant.

(67) In some embodiments, the yaw tabs are angled to keep edges from shearing water as water passes the side of the hull. In some embodiments, the main tabs are tapered to be longer on their inboard sides. With this tapered shape of the main tab, water flows with reduced turbulence off the main tabs 210 and meets with the water flowing off the middle wake tab.

(68) In some embodiments, when the boat takes off, the starboard and port trim tabs (and middle wake tab, if provided) are all automatically moved down by the controller 130 to create extra lift to improve initial hull acceleration, by reducing the drag of the hull in the water.

(69) In some embodiments, the deflections or sizes of the port trim tab 110 and starboard trim tab 120 are asymmetrical to account for propeller rotation. Propeller rotation affects surf waves. The propeller rotation twists water causing water to flow naturally in one direction. This flow also creates torque and makes it harder to roll the boat one way than the other. The use of asymmetrical port trim tab 110 and starboard trim tab 120 can help alleviate these propeller effects.

(70) Some embodiments provide default deflection percentages that are employed by the controller 130, for example. For example, when it is desired to surf on the port side, the starboard side main tab actuator 230 may be preset to move to 60% deflection, and the yaw tab actuator 260 may be preset to move to 100% deflection. Alternately, when it is desired to surf on the starboard side, the port side main tab actuator 230 may be preset to move to 75% deflection, and the yaw tab actuator may be set to move to 100% deflection. The reason for the different percentages is because of propeller rotation.

(71) In some embodiments, the boat has to be rolled further to one side, or yawed further to one side, to create a similar shaped wave than if there were no propeller effect. Such dissimilar amounts of rotation around the axes of the hull may be stored by some embodiments of controller 130. In certain embodiments, these dissimilar rotation amounts may be automatically integrated by controller 130 such that the operator of the wakeboat need not overtly consider them. In these embodiments controller 130 can be configured with the specifics of the boat in which it is installed and automatically adjust operator-specified rotation magnitudes to provide substantially similar behavior from the same numeric values.

(72) While not always necessary, some embodiments of the present disclosure may benefit from adjustments to the hull which ease the inducement of rotation around the roll and/or yaw axes. For example, longitudinal hull chinesoften employed to improve hull trackingmay be revised to allow more freedom of yaw rotation. Likewise, stabilizing chines which resist hull roll may be altered to improve the ability to impart rotation around the roll axis. Those skilled in the art will recognize these and other hull engineering decisions as they integrate various embodiments of the present disclosure into their boat designs. Reference has already been made to U.S. Pat. No. 9,828,075 to Hartman. Therein is described several techniques for measuring the yaw angle of a boat hull. Such yaw measurement techniques can be used in combination with some embodiments of the present disclosure to create a closed loop yaw management system. As noted in '075 to Hartman, Upon deriving the yaw angle as described above, some embodiments of the present disclosure use the yaw angle value to control the hull of the wakeboat. Referring to FIG. 9, system 154 can selectively control trim plates via connection Trim plate(s) power and sensing 414 to alter the yaw angle of the hull. The trim plates thus controlled may be oriented vertically, horizontally, or any other orientation suitable to the specific embodiment . . . . System 154 can repeatedly measure the yaw angle and apply ongoing adjustments to the hull to compensate for changing conditions (see Col. 25, Lines 9-25).

(73) The system of FIG. 1 may selectively include a yaw detector such as one of the yaw sensors, and/or employ one of the yaw sensing techniques, described in incorporated U.S. Pat. No. 9,828,075 to Hartman. While multiple yaw sensors and techniques are shown, in some embodiments only one type is employed. In other embodiments multiple types of sensors and techniques are employed. In some embodiments, a yaw detector comprises accelerometers 190 and 192. In some embodiments, a yaw detector comprises a fin type sensor 175. In some embodiments, a yaw detector comprises a rudder sensor 145 associated with rudder 146. In some embodiments, a yaw detector comprises trim tab sensors 115 and/or 125. In some embodiments, a yaw detector comprises hull pressure sensors 180 and/or 185. In some embodiments, a sensor comprises a GPS module 135.

(74) Referring to FIG. 1, some embodiments include controller 130 which selectively communicates with actuator 230 and actuator 260 on each trim tab in the embodiment. Controller 130 comprises a memory and other circuitry as necessary to interface with one of more of actuator 230 and actuator 260. In some embodiments, controller 130 may include a user interface whereby an operator can interact directly with controller 130.

(75) In some embodiments, controller 130 includes one or more electrical interfaces which enable it to selectively communicate with other controllers, systems, modules, and devices. These interfaces may comprise one or more of the following: Controller Area Network (CAN) interface, any of the various versions of Ethernet interface, any other wired interfaces whether standard or proprietary, optical interfaces, and wireless interfaces.

(76) In some embodiments, controller 130 is not limited to operating the actuators associated with the present disclosure. The functions and features of controller 130 may be integrated into other controllers, or controller 130 may include functions and features otherwise associated with other controllers.

(77) Certain embodiments use a single actuator to deploy both main tab 210 and yaw tab 240. In these embodiments a mechanical linkage coordinates the motion of main tab 210 and yaw tab 240, as imparted by the single actuator. This may be advantageous in embodiments, including retrofits to existing boat hulls, where space is limited or where connection 160 and/or connection 170 of FIG. 1 are limited in their capacity.

(78) Some embodiments are one-sided, e.g. they do not employ the trim tabs of the present disclosure in multiple locations. In some applications a single main tab 210 with yaw tab 240 is sufficient to achieve the desired functionality. For example, a wakeboat dedicated to wakesurfing only on one side may not require multiple trim tabs of the present disclosure, leaving more room available at the transom for other apparatuses. The present disclosure is suitable for use with any number of its trim tabs to achieve the desired behavior of hull 100.

(79) FIGS. 11 and 12 correspond to FIGS. 2 and 7, respectively, of above-incorporated U.S. patent application Ser. No. 15/824,787 (now U.S. Pat. No. 9,950,771).

(80) FIG. 11 shows a system 10 in accordance with various embodiments. Referring to FIG. 11, controller 130 may interact with some or all of the various other components, systems, and subsystems of system 12, if and when present on the wakeboat 9. System 12 selectively comprises any quantity of any of the following: hull sensors 111 such as draft, velocity, depth of water below the hull, heading, bearing, and angles of roll/pitch/yaw; ballast systems 121 for increasing or decreasing mass on the wakeboat 9; actuators 131 run by electricity, hydraulics, pneumatics, or other power sources; operator outputs 141 such as analog and digital gauges, graphical screens, indicators, lights, and acoustic transducers; operator inputs 151 such as touchscreens, switches, buttons, and knobs; wireless interfaces 155; hydrodynamic control surfaces 171; watercraft mass sensors 181; engine 14 and associated parameters such as RPM, temperatures, pressures, control settings such as throttle percentage, and fuel flow rates; and fuel, water, and other fluid level sensors 195.

(81) FIG. 12 illustrates one example of wakeboat operator input and output systems including displays of potential and actual performance. The display of FIG. 12 is a touchscreen, in some embodiments, and includes indication (output) and control (input) of parameters such as hull pitch angle, hull roll angle, control surface settings, vessel velocity, and so forth. The center of this display includes Highest Available Potential Indicator 1220 (labeled POTENTIAL) and Current Performance Indicator 1210 (labeled ACTUAL). In some embodiments, operator adjustment of the present performance level can be effected via touching and dragging Current Performance Indicator 1210 to the desired level. In other embodiments, the present performance level can be modified using the + 1240 and 1230 arrows at the bottom of the touchscreen display. Some embodiments of the present disclosure enable the use of multiple operator input techniques so any combination of the above, or additional, approaches may be supported.

(82) A variety of surf mode operator inputs are employed by some embodiments of the present disclosure. FIG. 12 shows one example. Actuation of surf operator input 1250 can selectively effect a surf left configuration of the hull in the surrounding water by selective positioning of the trim tabs. Likewise, actuation of surf operator input 1260 can selectively effect a surf right configuration of the hull in the surrounding water by selective positioning of the trim tabs.

(83) A further enhancement, provided by some embodiments of the present disclosure, is the ability of controller 130 to store the value represented by Current Performance Indicator 1210 in a configuration memory 105 and later recall it for automated or semi-automated duplication. Some embodiments of the present disclosure may store the value represented by Current Performance Indicator 1210 in configuration memory 105 together with many other configurable aspects of the wakeboat's operation including but not limited to control surface parameters and/or hull speed.

(84) In compliance with the patent laws, the subject matter disclosed herein has been described in language more or less specific as to structural and methodical features. However, the scope of protection sought is to be limited only by the following claims, given their broadest possible interpretations. The claims are not to be limited by the specific features shown and described, as the description above only discloses example embodiments.