Abstract:
A power plant extracts energy from a free flowing motive fluid by means of a turbine mounted on a gimbal. The shroud element of the fluid intake has external rudders, in conjunction with the gimbal mounting, enabling the enclosed turbine to instantaneously respond to changes in the direction of the free flowing motive fluid thus ensuring the face area of the intake is always physically orthogonal to the direction of the motive fluid streamlines. The shroud element may also be buoyant so as to optimally extract energy from an upper non-turbulent and higher velocity layer of the free flowing motive fluid. To function within an inherently unsteady source of energy, the preferred embodiment of the turbine is coupled to a DC generator which may further be coupled to a voltage and current regulating circuit which either charges a battery, performs electrolysis of water to produce hydrogen fuel, or is further coupled to a DC motor coupled to an AC generator. Alternatively an AC induction generator may be coupled to the turbine. Other mechanical, electrical, electronic, or electromechanical features may optionally be implemented to perform such tasks as adaptively locating the turbine in the maximum velocity flow, adapting internal vane and runner blade pitches for various flow rates and loads, keeping the intake free of obstructions, preventing loss of aquatic life, controlling and communicating the state of charge of the battery, or gauging and controlling the electrolysis process and communicating the fullness of the hydrogen gas output tanks.

Description:
BACKGROUND OF INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention is generally in the field of power plants. More specifically, the present invention is in the field of hydrokinetic turbines with means to adapt to changes in streamline direction and magnitude of a free flowing motive fluid.  
         [0003]     2. Description of Prior Art  
         [0004]     For over two thousand years mankind has known of harnessing the kinetic energy in flowing water to perform mechanical endeavors. In the past two hundred years the pace in which developments emerged in the practice of hydraulics has accelerated. The advent of the turbine in the first half of the nineteenth century culminated in the present advancements in hydroelectric generation, with this period of innovation and intense interest peaking in the first quarter of the twentieth century. Since then, fossil fuels have dominated as the high net energy, readily available energy source in the production of electricity and other conveyors of power. With known fossil fuel reserves at what presently appears to be arguably half depleted, as well as the environmental impact of using a polluting energy source, there is a strong need to develop a renewable and sustainable source of energy to support humankind.  
         [0005]     Presently the hydroelectric power plant industry earns revenues of approximately thirty billion dollars annually, but unfortunately is in a state of decline mainly due to the environmental and civic costs of implementing the existing technology. Environmental impact of the prior art hydroelectric power plant threatens extinction to aquatic species living downstream from the proposed power plant infrastructure, and also displaces all human inhabitants that live in what would become the flood plane of the infrastructure. It is estimated that over sixty million people have been displaced in the past century due to hydraulic power plant development with no mention of the number of species of plant and animal that have gone extinct. Furthermore, given the prior art technology, there still exists the possibility of life threatening flooding occurring downstream from the site of the hydraulic power plant infrastructure. Overall these costs have weighed heavily in civic planners&#39; decisions in adopting hydroelectric power generation to the point of putting the industry in a state of such decline that leading companies involved in this business are contemplating other areas of endeavor.  
         [0006]     Inherent problems in the prior implementation of hydroelectric power generation have exacerbated the present state of declining interest in this technology. The earliest implementation of hydrokinetic systems, commonly known as waterwheels, allowed less impact to the natural flow of the body of water from which these systems drew energy. With the greater efficiency gained by enclosing the impeller within the turbine came the need for more sophisticated penstock arrangements, which included greater infrastructure in the form of dams incurring the majority of the civil and environmental costs. The penstock, gate and impeller arrangements for these systems are physically coupled to sustain a given range of flow velocities and pressures over varying head and load so to maintain required synchronization to the end electrical alternating current output. This requirement imposes on these systems almost exclusive implementation in fresh-water systems with large scale infrastructure, increasing impingement on human habitats, and for the most part, neglecting the significant kinetic energy recoverable from one or more of various forms of oceanic flow.  
         [0007]     Other prior art exists where the motive fluid is ocean water, but still requires significant infrastructure. In one form, dam like structures known as barrages compel tidal flow to affect a turbine. Some turbines exist that operate in free flow, but do not adapt to changes in direction and have limited capacity, typically less than a kilowatt. In another recently developed form, offshore platform structures behave as pistons on waves at medium depths, in turn pumping a motive fluid through a turbine and then requiring a long distance power cable generally carrying high voltage direct current back to shore, to be further processed. This likely incurs significant maintenance costs for the offshore platforms. Fully implementing this prior technology would likely impede shipping lanes as a farm of these platforms effectively fences the shoreline. This stands as one of several known environmental impacts of this prior technology with others hypothetically existing.  
         [0008]     When one amortizes the total amount of energy that goes into building and maintaining a prior art hydroelectric power installation, it becomes obvious that it takes a considerable amount of time before the plant becomes net energy positive, or in other words, the point when the total investment of energy compared to the total recovery of energy is at the break-even point. As a further example, fossil fuel, not being a renewable resource, requires mining or drilling deeper and pumping farther to obtain a lower yield and lower quality of fuel incurring more costly refining to recover the remaining reserves at the end-of-life of a mine or a well. Thus, fossil fuel as an energy source clearly diminishes in net energy as time goes on, until it obviously becomes a sink, no longer a source. This latter example reinforces the inevitability of mankind&#39;s undeniable need for a sustainable and renewable source of energy. Contemplating the net energy curves of a renewable energy source and fossil fuel indicates a sense of urgency for the development of a renewable source. The timing of the cross-over point of when one source becomes net energy positive as the other becomes net energy negative will dictate the severity of the ensuing energy crisis and thus the impact on humanity. As time goes on it will be less likely an option to expend a great deal of energy as an investment while more mundane needs are no longer being met. Despite this sense of urgency in the need to develop renewable, sustainable sources of energy, as previously stated hydroelectric power plant development is actually declining.  
         [0009]     Therefore, there exists a fundamental need for developing renewable and sustainable sources of energy including further exploitation of readily available known resources. More specifically, there exists a need for a novel approach to ensure low impact to environment and low civic infrastructure costs such that the energy investment return is most quickly realized. Utmost, to optimally exploit oceanic energy, such as that which arrives onshore, adaptability to inherently unsteady flow is prerequisite of any such system. A system that can achieve the above-specified goals would readily attain a relatively high net energy soon after its inception.  
       SUMMARY OF INVENTION  
       [0010]     The present invention achieves the goals of overcoming existing limitations of present day hydroelectric power generation systems by first and foremost having the ability to extract power from a free flowing fluid. While prior art exists which functions in free flowing bodies of water, the novelty of this invention lies in its ability to respond and adapt to any change in the magnitude and direction of the streamlines of the free flowing motive fluid. This enables this invention to extract energy from breaking ocean waves, presently an untapped but readily available known source of energy.  
         [0011]     Secondly, because adapting to change of both magnitude and direction of the streamlines of a free flowing motive fluid formed the basis of the guiding concepts of the present invention; this also avails the present invention the applicability to other bodies of water besides the ocean. Having been conceived for free flowing motive fluid use obviates the prior art&#39;s inherent need for large-scale infrastructure and thus eliminates two fundamental disadvantages presently challenging the hydroelectric power industry. The present invention does not require this scale of infrastructure and therefore greatly diminishes the environmental impact while attaining a positive net energy earlier upon implementation.  
         [0012]     Overcoming the conceptual need for synchronization to the electric power grid positions the present invention as desirable for implementation in gathering energy for the emerging power conveyance systems, especially hydrogen fuel and fuel cell technology. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0013]      FIG. 1  illustrates a general perspective view of an exemplary apparatus in accordance with a preferred embodiment of the present invention.  
         [0014]      FIG. 2  illustrates a cross-sectional view length-wise along the turbine shroud in  FIG. 1  according to a preferred embodiment of the present invention.  
         [0015]      FIG. 3  illustrates a cross-sectional view length-wise along the turbine shroud in  FIG. 1  according to an alternate embodiment of the present invention.  
         [0016]      FIG. 4  illustrates a partially exploded perspective view of the pinion and motor mechanism for adjusting the interior flow vanes, runner blades, and gate wickets in  FIG. 2 .  
         [0017]      FIG. 5  illustrates an alternate view of the circular rack gear and motor rotor shaft pinion in  FIG. 4 .  
         [0018]      FIG. 6  illustrates the preferred means of bi-directional anti-backlash and position locking mechanism for the circular rack gear in  FIG. 4 .  
         [0019]      FIG. 7  illustrates the flowchart for synchronizing the bi-directional anti-backlash and position locking solenoid in  FIG. 6  to the motor in  FIG. 4 .  
         [0020]      FIG. 8  illustrates a partially exploded perspective view of the pinion and motor mechanism for adjusting the external rudders of the alternate embodiment in  FIG. 3 .  
         [0021]      FIG. 9  illustrates a system of gears that increases the rotational velocity of the rotor of a generator compared to directly coupling the rotor to the actuating member.  
         [0022]      FIG. 10  illustrates the mounting system affixed to a rail system in accordance to the preferred embodiment.  
         [0023]      FIG. 11  illustrates a system of buoys equipped with accelerometers and their respective vector output signal profiles relative to position of breaking waves for one embodiment.  
         [0024]      FIG. 12  represents a schematic view of an AC induction generator directly coupled to the output shaft of the coaxial fluid coupler according to one embodiment.  
         [0025]      FIG. 13  represents a schematic view of an AC induction generator indirectly coupled to the output shaft of the coaxial fluid coupler through the system of gears in  FIG. 9  according to one embodiment.  
         [0026]      FIG. 14  represents a schematic view of a DC generator directly coupled to the output shaft of the coaxial fluid coupler according to one embodiment.  
         [0027]      FIG. 15  represents a schematic view of a gear indirectly coupled to the rotor of an auxiliary DC generator through the system of gears in  FIG. 9  according to one embodiment.  
         [0028]      FIG. 16  illustrates the flowchart for control of the complete system according to the preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0029]     The present invention is directed to a gimbal-mounted hydroelectric turbine for adaptively extracting energy from a free flowing motive fluid that continuously changes direction and magnitude of flow. The following description contains specific information pertaining to various embodiments and implementations of the present invention. One skilled in the art will recognize that the present invention may be implemented in a manner different from that specifically depicted in the present specification. Furthermore, some of the specific details of the invention are not described in order to maintain brevity and to not obscure the invention. The specific details not described in the present specification are within the knowledge of a person of ordinary skills in the art. Obviously, some features of the present invention may be omitted or only partially implemented and remain well within the scope and spirit of the present invention.  
         [0030]     The following drawings and their accompanying detailed description are directed as merely exemplary embodiments of the invention. To maintain brevity, some other embodiments of the invention that use the principles of the present invention are specifically described but are not specifically illustrated by the present drawings, and are not meant to exhaustively depict all possible embodiments within the scope and spirit of the present invention.  
         [0031]      FIG. 1  illustrates a general perspective view of an exemplary apparatus in accordance with one embodiment of the present invention. Arrow  100  indicates direction of the approaching flow of the free flowing motive fluid, impinging upon the face of the intake of the turbine, shown covered with a screen  103 . The fundamental purpose of the screen  103  is to prevent loss of life of fish and other aquatic life forms as well as prevent various forms of debris from entering the turbine and obstructing normal operation. Arrow  101  is shown exiting the back of the turbine and is of different shape than arrow  100  to indicate a change in velocity through the turbine due to the difference in area of the intake compared to the draft area at the runner blades. This ratio of intake area to draft area, as well known for about four centuries in the science of fluid dynamics for incompressible flow, is equal to the ratio of draft velocity to intake velocity. This difference in area of the draft compared to the intake may obviously be inferred by the physical profile of the turbine shroud  102  in both  FIG. 1  and  FIG. 2 , though the drawings are not necessarily to scale of the preferred embodiment. The factors governing the necessity of increasing the velocity of the flow through the turbine will be addressed subsequently. Note that the circular geometry of the intake and the shroud area implies use of a coaxial fluid coupler and henceforth changing to a rectangular intake and a crossflow impeller does not represent a significant departure from the scope of the present invention. Subsequent paragraphs in this specification will address the basis for choosing a coaxial impeller.  
         [0032]     A fundamental and significant departure from prior art that provides considerable novelty in this invention is the implementation of the external vanes or rudders  104 ,  105 , and  106  and the circular bearings  107 , and  109 . The combined use of circular bearings  107  and  109  comprise what results in a mechanical apparatus that one could commonly refer to as a two-axis gimbal, providing two degrees of freedom, specifically, freedom to move in any direction that has vector components that are parallel to a horizontal or a vertical plane. As depicted in  FIG. 1 , circular bearing  107  and its complement not shown but also affixed to the semi-elliptical follower brace  120  on the opposite side, with concentric pins affixed to the turbine shroud  102 , forms an axis orthogonal to, and allows the turbine any motion parallel to, the vertical plane, whereas circular bearing  109  forms an axis orthogonal to, and allows the turbine any motion parallel to, the horizontal plane. For instance, as the free flowing motive fluid changes direction of its streamlines parallel to the horizontal plane by any arbitrary angle, this change in direction will exert a force on both rudders  104  and  106  causing torque about the bearing  109  resulting in motion parallel to the horizontal plane as represented by arrow  110  until arrival at mechanical equilibrium. Likewise, as the free flowing motive fluid changes direction of its streamlines parallel to the vertical plane by any arbitrary angle, this change in direction will exert a force on rudder  105  and a complementary rudder not shown on the opposite side of the shroud  102 , causing torque about the bearing  107  and its complementary bearing not shown on the opposite side of the semi-elliptical follower brace  120 , resulting in motion parallel to the vertical plane as represented by the arrow  108  until arrival at mechanical equilibrium. Thus the present invention adapts to any change in direction of the streamlines of a free flowing motive fluid. Obviously, adding or removing either a rudder or an axis to the gimbal employed within the preferred embodiment of the present invention would not constitute a substantial departure beyond the scope of the invention.  
         [0033]     Proceeding further with the features depicted in  FIG. 1 , the semi-elliptic follower brace  120 , is affixed to the outer casing of the circular bearing  109 , the inner case of the bearing  109  is affixed to the sliding main shaft collar  111 . The sliding main shaft collar  111  is illustrated in  FIG. 1  as having a slotted tongue-and-groove arrangement  112 , captivated by a non-binding washer  113  affixed through a screw to the main shaft  115 . Said sliding assembly comprised of the slotted tongue-and-groove arrangement  112 , and non-binding washer  113  permits the sliding main shaft collar  111  freedom of motion in the vertical direction as depicted by arrow  114 . Note that the scale of this drawing is somewhat distorted in order to clearly display the sliding main shaft collar  111 , the slotted tongue-and-groove arrangement  112 , and the non-binding washer  113  sliding assembly whereas in the preferred embodiment the entire turbine and especially the diameter of the screen-covered face of the intake  103  would be scaled considerably larger than this main shaft assembly. While said assembly allows the freedom of motion in the vertical direction as depicted by arrow  114 , the cause of such motion corresponds to variation in the level of the surface of the motive fluid as tracked by buoyancy of the shroud  102 . The means of this buoyancy is further depicted in  FIG. 2  and will be further addressed in subsequent paragraphs. The buoyancy causes the turbine to track the variation in the level of the surface of the motive fluid and thereby enables the turbine to always extract energy from an upper layer of the motive fluid, which is less susceptible to the effects of friction namely turbulence at the floor of the waterway. Thus the flow impinging the face of the turbine is less likely to be turbulent, more likely to be laminar, permitting more optimal extraction of energy. Clearly any variation in the above assembly including any change to the main shaft  115 , the slotted tongue-and-groove arrangement  112 , the non-binding washer  113 , the sliding main shaft collar  111  or the buoyancy of the shroud  102 , that continues to permit the intake of the turbine to extract energy from an upper, non-turbulent layer of the motive fluid does not constitute a substantial departure beyond the scope of the present invention.  
         [0034]     The main shaft  115  is shown in  FIG. 1  attached to the base  116 . Under the base is a system of rollers  117  riding on a set of rails  119  driven from under the base  116  through the drive axle  118 . Further detail of the drive system will be depicted in  FIG. 10  and in subsequent paragraphs. The primary purpose this rail system serves is to optimally locate the entire turbine system adaptively to an area of flow where maximum energy may be extracted. A secondary purpose could include facilitating maintenance on any part of the system at a more convenient location than its in-service location. A third purpose could be for moving the turbine out of the way of any vessel needing to pass in the present vicinity of the turbine. Clearly any deviation from the above stated system, such as a winch and pulley system, which continues to allow the turbine system to be adaptively positioned, does not constitute a substantial departure beyond the scope of the present invention. Maximum energy extraction location for the unit has been initially considered the onshore side of breaking ocean waves but can be any area of highest velocity of flow in any body of motive fluid. One alternate example of this could be any body of water that has flow patterns that vary diurnally or seasonally.  
         [0035]     Let it be known that the aforementioned features that enable the turbine to namely: adapt to any change in the direction of the streamlines of a free flowing motive fluid; extract energy from an upper, non-turbulent layer of water due to buoyancy of its shroud; adaptively position the turbine in an optimal flow location using the rail system; while originally conceived for accommodating use in breaking ocean waves, obviously are advantageous for use in other bodies of water such as, but not limited to rivers, creeks, inlets, tidal bores, rapids, or waterfalls. Therefore, use of the present invention in any body of water other than breaking ocean waves does not constitute a substantial departure beyond the scope of the present invention.  
         [0036]      FIG. 2  illustrates a cross-sectional length-wise view interior to the shroud  102  of the turbine. The broken line defined by points  200  and  201  indicates the vertical plane is where the section is cut and the arrows proceeding from points  200  and  201 indicate the perspective direction of sight. The hatching of shroud  102  indicates it is the only element cut in this cross-sectional view with everything else contained within the shroud  102  remaining unaltered in this view. The hatch line delineates the shroud  102 , and its cross-sectional circumference can be seen in  FIG. 2  as creating an inner surface and outer surface and the cavity  202  within the inner and outer surfaces of the shroud  102 . This cavity  202  is proposed to create the buoyancy of turbine unit itself. The cavity  202  may be filled with a material such as polystyrene foam that provides both structural support and buoyancy, or if less expensive, left vacant with the shroud  102  constructed or assembled watertight. This shroud  102  may also alternatively be constructed in such a manner as to render the cavity  202  gas-tight and useful in containing the output fuel—hydrogen gas as the end product if the energy captured by this turbine is used in the process of electrolysis of water. Further elaboration on this cavity  202  for use in the production of hydrogen fuel will follow.  
         [0037]     As discussed previously the contour of the shroud  102  especially its inner surface is seen in  FIG. 2  to form a decreasing area orthogonal to the streamlines and thus causes the velocity of flow of the motive fluid to increase proportionally as it approaches the coaxial fluid coupler  210  in the draft area of the turbine from the screen-covered intake  103 . This flow velocity as it thrusts upon the runner blades  211  actuates the rotational velocity of the coaxial fluid coupler  210  which affects the rotational velocity of the rotor of the generator contained within the generator housing  206 . Ultimately, the choice of generator and particularly its synchronous speed predicates all requirements of flow velocity and will be discussed in more detail subsequently. In general, it may be stated at this point that the operation of the turbine would likely benefit from increasing the average flow velocity through the turbine since other means for reducing the effective velocity are readily attained. One such means of reducing the flow velocity includes closing the gate by rotating its wickets  203  as portrayed by arrows  205 . Closing the gate in this manner will cut-off flow which serves to reduce the rotational velocity of the coaxial fluid coupler  210  thus reducing the forces of gyroscopic precession so to quicken the response of the gimbal to changes in direction of the streamlines of a free flowing motive fluid as it exerts a force on the exterior rudders  104 ,  105 ,  106 . Continuous adjustment of the flow velocity can be achieved through altering the pitch of the interior flow vanes  207  and runner blades  211 .  FIG. 2  shows the direction of rotation of the interior flow vanes  207  by arrow  208  and the direction of rotation of the runner blades  211  about their bearings  213  by arrow  212 . While only two interior flow vanes  207  are shown, it should be understood that in the preferred embodiment a minimum of at least four interior flow vanes  207  and as many as eight or twelve could be implemented and likewise a plurality of runner blades  211  could be implemented. The rotation and fundamental shape of the interior flow vanes  207  can reduce the effective area and thus increase flow velocity while channeling the flow into near vortical circulation as it thrusts upon the runner blades  211  at an angle optimal for energy extraction. This channeling of the flow could effectively transform turbulent flow at the screen-covered face  103  into laminar or vortical flow through the turbine. While some loss of energy may result from the friction on the sides of the interior flow vanes  207 , coherently altering the pitch of the interior flow vanes  207  and the runner blades  211  optimizes the efficiency of the turbine over a range of flow velocities and generator loads. The algorithm for control of the pitch of the interior flow vanes  207  and the runner blades  211  is illustrated by  FIG. 16 , the mechanism for this control is illustrated by  FIGS. 4, 5 ,  6  and  7  and is discussed in further detail in subsequent paragraphs.  
         [0038]     One skilled in the art may recognize the turbine in the preferred embodiment of the present invention as a variation of the turbine invented by Viktor Kaplan in the first quarter of the twentieth century. The choice of this type of turbine, particularly a member in the class of impulse turbines originates from the notion that a free flowing motive fluid is inherently impulsive in nature, i.e. energy is optimally extracted by mechanically responding to the forces of a changing flow velocity impinging upon the turbine blades; as opposed to a member in the class of reaction turbines which derives energy in a system where static pressure in the draft area draws the runner into motion, an action similar to that of a siphon. In particular, the Kaplan turbine is well suited for adapting to changes in flow magnitude due to its adjustable flow vanes and runner blades, and is most often implemented in structures of low head, implying low static pressure in the draft characteristic of, and more resembling an impulse turbine and thus most analogous to use in breaking ocean waves. Nevertheless, implementation of a reaction turbine that responds to changes in direction and magnitude of the streamlines of a free flowing motive fluid in any manner similar to that of the present invention does not constitute a substantial departure beyond the scope of the present invention. Furthermore, it may be advantageous to implement the present invention with a turbine of recent advent that boasts of being bladeless, as it is well known that seawater is particularly corrosive to metals, breaking waves notably high in particulates, and thus a bladed runner highly susceptible to pitting on the blades and perhaps costly in terms of maintenance. In light of the aforementioned, this modification of a Kaplan turbine in the preferred embodiment is purely exemplary, illustrative and not restrictive. Thus, regardless of the impulse or reaction classification of such a bladeless turbine, an implementation of such a bladeless turbine that responds to changes in direction and magnitude of the streamlines of a free flowing motive fluid in any manner similar to that of the present invention does not constitute a substantial departure beyond the scope of the present invention.  
         [0039]      FIG. 3  illustrates a cross-sectional length-wise view interior to the shroud  102  of an alternate embodiment of the present invention that includes exterior rudders that are rotatable. The points  300  and  301  define the cross-sectional plane and angle of perspective in the same manner as points  200  and  201  in  FIG. 2 . The fundamental difference of this alternate embodiment of the present invention as depicted in  FIG. 3  versus the embodiment shown in  FIG. 2  is in the implementation of rotatable rudders  302 ,  303  versus fixed rudders,  104 ,  105 ,  106 , respectively. Arrows  306 ,  308  encircling the shafts  305 ,  307  depict the direction of rotation of these rudders. The purpose of furnishing the turbine with rotatable rudders  302 ,  303  is, as before while in the same position as the fixed rudders  104 ,  105 ,  106 , to enable the gimbal-mounted turbine to adapt to changes in the direction of the streamlines of the free flowing motive fluid. The additional benefit of rotatable rudders  302 ,  303  is to affect a change in the orientation of the face of the screen-covered intake  103  by assuming an alternate position with respect to the fixed rudders  104 ,  105 ,  106 . By rotating the rudders  302 ,  303 , in case over a long period of use the screen-covered intake  103  gets covered with tenacious debris such as seaweed, the turbine changes orientation such that the face is no longer orthogonal to the streamlines of the motive fluid thereby allowing the motive fluid to wash the debris from the screen-covered intake  103 . This alternate embodiment exhibits another difference resulting from the aforementioned rotatable rudder feature that can be seen by comparison of the support columns  209  of  FIG. 2  and the support columns  304  of  FIG. 3 . The modification to include hollow areas in the support columns  304  in which concentrically situated shafts  305 ,  307  drive the rotatable exterior rudders  302 ,  303  embodies the conduit for torque to the rotatable rudders  302 ,  303  originating from a driving motor member contained within the generator housing  206 . Conversely, the support columns  209  of  FIG. 2  strictly structurally reinforce the generator housing and impart power and control signals through slip rings in the columns  209  in the vicinity of the gimbals on the same axis as bearing  107  and its complement not shown on the opposite side of the turbine shroud  102 . Greater detail into how power and control signals are routed as well as the mechanism for the rotatable rudders  302 ,  303  and the control of it follows in  FIGS. 6, 7 ,  8 , and  16 , and subsequent paragraphs.  
         [0040]      FIG. 4  illustrates a partially exploded perspective view of the pinion and motor mechanism for adjusting the interior flow vanes, runner blades and gate wickets in  FIG. 2 . When an adjustment in any of the set of interior flow vanes  207 , runner blades  211 , or gate wickets  203  becomes necessary, for each set of interior flow vanes  207 , runner blades  211 , or gate wickets  203  one instance of the motor in  FIG. 4  in the preferred embodiment a DC stepper motor  404 , with its stator windings  410 ,  411  energized in the appropriate sequence, actuates rotational motion in its rotor shaft  403 , in this example represented by arrow  413 . The DC motor  404  has at the end of its rotor shaft  403  affixed to, forge or cast into a pinion  402  that meshes with the inner gear of a circular rack gear  400 . Briefly directing the discussion to  FIG. 5 , an alternate view of this circular rack gear  400 , meshing its inner gear  401  with the pinion  402  affixed, forged, or cast onto rotor shaft  403  is shown. Returning to  FIG. 4 , one can see the outer gear of the circular rack  400  engages the pinions  405 ,  406 ,  407  affixed, forged, or cast to the actuator shafts  408 ,  409 . These actuator shafts  408 ,  409  represent any one of plural instances of the shafts previously alluded to, the shafts that drive the set of interior flow vanes  207 , runner blades  211 , or gate wickets  203 . The mechanism driving the shafts  305 ,  307  for the rotatable rudders  302 ,  303  has some minor differences and is portrayed in  FIG. 8  and will be addressed subsequently. The gear ratio of the pinion  402  to the inner rack gear  401  multiplied by the gear ratio of the outer rack gear of the circular rack  400  to the actuator shaft pinions  405 ,  406 ,  407  defines the translation of torque and angular displacement derived from the rotor shaft  403  resulting in the motion on the actuator shafts  408 ,  409  depicted by arrows  414 ,  415 ,  416  corresponding to each of the interior flow vanes  207 , represented by arrows  208 ; each of the runner blades  211 , represented by arrow  212 ; or each of the gate wickets  203 , represented by the arrows  205 . Because a singular instance of the mechanical assembly given in  FIG. 4  actuates one set of each of the interior flow vanes  207 , runner blades  211 , or gate wickets  203 , the location of these assemblies may be found in separate locations within the turbine shroud  102 . In the preferred embodiment, the location for the assembly of  FIG. 4  for the interior flow vanes  207  would optimally be placed within a central location of the generator housing  206 ; the location for the assembly of  FIG. 4  for the runner blades  211  would optimally be placed within a central location of the coaxial fluid coupler  210 ; while the location for everything to the left of the shaft  403  of the assembly of  FIG. 4 , if not the entire assembly itself for the gate wickets  203  would optimally be placed within a central location of the fixed gate shaft  204 . The advantage of using the circular rack gear  400  versus a simple worm gear mechanism is that especially in the instance of the interior flow vanes  207 , the circumference of the inner gear  401 , as most visible in  FIG. 5 , avails maximal clearance for the generator, itself. Obviously, a simple worm gear or single pinion to shaft coupling gear, for example the rack gear  400  directly affixed to the rotor shaft  403 , may be implemented where central clearance is not critical. While this means of actuating motion in the interior flow vanes, runner blades, or gate wickets presents a novel departure from prior art, this preferred means is purely discussed in an exemplary manner, illustrative, not restrictive, and therefore any deviation from the above specification does not constitute a significant departure beyond the scope of the present invention.  
         [0041]     Several fundamental advantages arise from employing a DC stepper motor  404 , in actuating motion in the interior flow vanes  207 , runner blades  211 , gate wickets  203 , or rotatable rudders  302 ,  303 . The stepper motor is inherently a precise means of translating rotational displacement and therefore requires no feedback, or in other words may be implemented in an open-loop configuration affording more circuit complexity devoted to higher-level control of the system. Secondly, given the preferred means of bi-directional anti-backlash and position locking mechanism for the circular rack gear  400  as illustrated in  FIG. 6 , the stator coils  410 ,  411  of the DC stepper motor need powering only in the instances of performing an adjustment, serving to improve the overall efficiency of the turbine. Also, because this adjustment period comprises an exceedingly short duty cycle, in the order of tens of milliseconds every second in the most active member, the current for the stator coils  410 ,  411  is limited by the breakdown voltage of the coil winding insulation, not the thermal wear of the coil itself, as the average power dissipated by its resistive losses are averaged over a much longer period than its duty period. With the use of higher energizing currents, depicted by arrows  412 , comes the advantage of greater torque deliverable to the actuated members in a more space efficient sized DC stepper motor.  
         [0042]     In more detail, the components of  FIG. 6  includes to the right of the circular rack gear  400 , all the components previously defined in  FIG. 4  and the foregoing paragraphs, with the addition of a solenoid  600  with a plunger  602  that engages between the teeth of either the inner gear  401  or the outer gear of the circular rack gear  400  to stop motion in the actuated members. The actuated members were omitted from  FIG. 6  for sake of clarity though it could be presumed that the actuated members are situated as depicted in  FIG. 4  or  FIG. 8 . The torque translated back to the plunger  602  from the actuated members is contained by the mounting of the solenoid core  600  and the stops  603  cast or forged on the inner surface of the generator housing  206 , coaxial fluid coupler  210 , or fixed gate shaft  204 . The solenoid core  600  is shown spring loaded, with the solenoid spring  601  compressed by the retracted plunger  602  when the solenoid coil  604  has current flowing as depicted by arrows  605 , in accordance to the right-hand rule. The physical positioning of the solenoid  600  core and the DC stepper motor  404  and its shaft  403  is displayed in a collinear orientation to attest the importance of mounting these components along the central axis of the turbine mounted within the gimbal in such a manner as to not disrupt the balance necessary, otherwise mechanical oscillation may occur thereby harming the system efficiency and possibly causing stress and shortened life of various components.  
         [0043]      FIG. 7  illustrates the flowchart for synchronizing the bi-directional anti-backlash and position locking mechanism of  FIG. 6  to the pinion and motor mechanism of  FIG. 4 . From the start, the DC stepper motor stator coils  410 ,  411  and the bi-directional anti-backlash and position locking solenoid coil  604  is in the de-energized state  700 . When any of the aforementioned actuated components requires an adjustment, assuming the present position of one of these components coincides with the position of the DC stepper motor rotor shaft  403  when its stator coil  410  is energized, the stator coil  410  is once again energized, state  701 . Upon energizing the stator coil  410 , the solenoid coil  604  is energized with a current as depicted by arrows  605 , thereby causing the solenoid plunger  602  to retract and to unlock the present position by disengaging the plunger  602  from the teeth of the circular rack gear  400 , state  702 . Then to affect the necessary adjustment, assuming the position of the next step corresponds to energizing stator coil  411 , a current depicted in FIG.  6  by the arrows  412  energizes stator coil  411  while stator coil  410  is de-energized. This actuates the motion in the rotor shaft  403  depicted by arrow  413 ; the direction of this arrow is arbitrary as implied by the term bi-directional anti-backlash and position locking mechanism. This completes states  703  and  704  for this example, though the system could continue to step in this manner through an arbitrary number of stator coils on the DC stepper motor  404 , by reiterating state  703  as necessary to achieve the desired set point position of the rotor shaft for this adjustment. Upon obtaining the desired position, the solenoid coil  604  is de-energized by interrupting the current depicted by arrows  605 , thereby permitting the solenoid spring  601  to decompress causing the solenoid plunger  602  to re-engage the teeth of the circular rack gear  400  at the new position, performing the operation of anti-backlash and position locking, state  705 . Since this circular rack gear  400  is further coupled to plural actuated members through gears  405 ,  406 ,  407 , and there remains some play in the gears, this results in some motion associated with backlash in the actuated members. But the precision of the rack gear  400  should be fine enough that this resultant motion in the actuated members is negligible for the overall system response. In the final state  706 , the stator coil  411  is de-energized and the new position of the actuated member and of the corresponding stator coil is placed in a register, of discrete logic or microprocessor register or memory space, as DC stepper motors are amenable to digital control due to their discrete means of determining rotational displacement. More detail of the higher-level system control will follow in subsequent paragraphs and  FIG. 16 .  
         [0044]      FIG. 8  illustrates a partially exploded perspective view of the pinion and motor mechanism for adjusting the rotatable rudders  302 ,  303 . Most of the components of  FIG. 8  are analogous to  FIG. 4  with the exception of the circular rack gear  400  now having two beveled edges for the circular rack gear  800  of  FIG. 8 . Because the rotatable rudders  302 ,  303  need to move in the same direction in the horizontal plane to cause the screened face of the intake  103  to assume a non-orthogonal orientation with respect to the streamlines of the free flowing motive fluid, the pinion of one of the rotatable rudder shafts needs to mesh on the opposite side of the circular rack gear  800  compared to the pinion of the other rotatable rudder shafts.  FIG. 8  illustrates this requirement by displaying first the current  809  flowing through the stator winding  808  of the DC stepper motor  804 , assuming the current previously flowed in stator winding  807 , causing the rotor shaft  803  to rotate in the direction of arrow  810 . As before, in the preferred embodiment, because the bi-directional anti-backlash and position locking mechanism in  FIGS. 6 and 7  captivates the circular rack gear  800  while at rest, the direction of rotation depicted by arrow  810  is arbitrary. The motion depicted by arrow  810  causes the circular rack gear  800  to rotate in the same direction due to the meshing of the rotor shaft pinion  802  to the inner gear  801  of the circular rack  800 , whose outer gear meshes with the actuator shaft pinions  805 ,  806  resulting in motion shown by arrows  811 ,  812 . Actuator shafts  305 ,  307  thus turn the rotatable rudders  302 ,  303  in the same direction in the horizontal plane. As with the other actuators, the gear ratio of the rotor shaft pinion  802  to the inner rack gear  801  multiplied by the gear ratio of the outer rack gear of the circular rack  800  to the actuator shaft pinions  805 ,  806 , defines the translation of torque and angular displacement derived from the rotor shaft  803  resulting in the motion on the actuator shafts  305 ,  307  depicted by arrows  811 ,  812 , corresponding to the torque and angular displacement of the rotatable rudders  302 ,  303 . As shown in  FIG. 3 , because the rotatable rudder shafts  305 ,  307  conjoin within a central location of the generator housing  206 , and the circular rack gear  800  is perfectly analogous to the circular rack gear  400 , the circumference of the inner gear  801  or as most visible in  FIG. 5 , the circumference of inner gear  401 , avails maximal clearance for the generator, itself. Obviously, a simple worm gear or single pinion to shaft coupling gear, for example the rack gear  800  directly affixed to the rotor shaft  803 , may be implemented where central clearance is not critical. While this means of actuating motion in the rotatable rudders presents a novel departure from prior art, this preferred means is purely discussed in an exemplary manner, illustrative, not restrictive, and therefore any deviation from the above specification does not constitute a significant departure beyond the scope of the present invention.  
         [0045]      FIG. 9  illustrates a system of gears that decreases rotational velocity and displacement from the rotor shaft of a motor to an actuated member, or conversely, increases rotational velocity and displacement from an actuating member to a rotor shaft of a generator. Member  900  may either be an AC induction or a DC generator or motor depending on the synchronous speed of the rotor compared to the armature current frequency in the case of the AC induction motor or generator, or in the case of the DC motor or generator, the direction of the armature current depicted by arrows  909 , flowing through the armature coil  901 . Therefore the speed voltage presented across the conductors of the armature coil  901  by the current  909  is proportional to the rotational velocity of the actuator  908  represented by arrow  912  multiplied by the ratio of gear  907  to gear  906  multiplied by the ratio of gear  904  to gear  903 . The arrows  910 ,  911 , and  912  merely describe the translation of motion through the gears. The physical positioning of the actuator  908  and the motor or generator  900  and its rotor shaft  902  is displayed in a collinear orientation, though as some implementation of these mechanical components of  FIG. 9  most likely will not occupy a location within the turbine shroud  102 , this is purely shown as a means most efficient for space. In some embodiments this mechanical assembly will occupy a space within the generator housing  206  and thus the actuator  908 , the motor or generator  900 , its rotor shaft  902  and the tertiary shaft  905  is displayed in  FIG. 9  in a collinear orientation as previously, to attest the importance of mounting these components along the central axis of the turbine mounted within the gimbal in such a manner as to not disrupt the balance necessary, otherwise mechanical oscillation may occur thereby harming the system efficiency and possibly causing stress and shortened life of various components. This specification will expound upon the purpose of this mechanical assembly in  FIG. 9  in subsequent paragraphs and in  FIGS. 13 and 15 .  
         [0046]      FIG. 10  details the base  116  and associated mechanical components below it. The broken line defined by points  1000  and  1001  indicate alternate views. The left side of the broken line  1000 - 1001  views from underneath the center of the base  116  looking outward orthogonal to the rails, while the right hand side of the broken line  1000 - 1001  views the underneath of the base  116  from a distance parallel to and in between the rails  119 . The base  116  rests on the supports  1008  coupled to the axle of the rollers  117 . The rollers  117  rotate freely on the rails  119 . The rails  119  are secured to a foundation  1002 . In the preferred embodiment, this foundation  1002  is formed reinforced concrete, though it could consist of the local natural rock formation depending upon where the application of this invention occurs. Ideally this foundation  1002  is located on the tip of a headland formation where wave energy is most focused, and is sloped of adequate angle with respect to the true horizon so to elicit breaking waves of the plunging or surging type that transfer wave energy into particle velocity in a most concentrated location and succinct time frame. The rails  119  have cutouts  1003  that permit cross flow and thus prevent sand from drifting to the point of obstructing the movement of the drive gears  1005  that meshes with the rail rack gear  1004 . When stationary, the drive gears  1005  lock indirectly by coupling through its axle  118  to an internal drive gear not shown locked by a means such as the previously described bi-directional anti-backlash and position-locking mechanism to hold the drive gears  1005  steady in the path along the rail which also create tension to hold the system upright against any lateral tilting force. In the preferred embodiment, the means of driving the gears, again most easily implemented as a DC stepper motor, will likely occupy an area in the lower portion of the main shaft  115  or perhaps a compartment not shown under the base  116 . The rotor shaft of this motor therefore occupies a location concentric to the drive shaft housing  1006  and has a worm gear not shown on its end occupying the gear box  1007 . Said worm gear meshes with the internal drive gear, not shown inside the gear box  1007 , but parallel to the gears  1005  and mounted such that it directly drives the axle  118 . The bi-directional anti-backlash and position locking mechanism not shown also occupies the gear box  1007  and mates and locks the internal drive gear not shown inside the gear box  1007 . A detailed discussion of exemplary sensor input means and the control algorithm itself for the above rail system follows in subsequent paragraphs describing  FIG. 11  and  FIG. 16 .  
         [0047]      FIG. 11  illustrates a system of buoys  1104 ,  1107 ,  1110 ,  1113  mounted in a collinear orientation parallel to the ordinary direction of onshore flow of breaking waves, orthogonal to the tangent of the shoreline  1100 . This system of buoys aids in adapting the gimbal-mounted turbine to maximal flow along the path of the aforementioned rail system. The buoys  1104 ,  1107 ,  1110 ,  1113  are equipped with accelerometers or other means of measuring force or acceleration and their output signal profiles  1105 ,  1106 ,  1108 ,  1109 ,  1111 ,  1112 ,  1114 ,  1115 , respectively portray characteristics relative to the position of breaking waves. For example, the buoy  1113  shown to the right, or offshore from the breaking wave  1103  has accelerometers or any other means of measuring force or acceleration including but not limited to spring actuated scales. Here the accelerometers mounted on buoy  1113  outputs two unique signals, i.e. voltages, corresponding to physically a horizontal component and a vertical component of force or acceleration which over time span the range delineated by arrows  1114  and  1115 , respectively. Because this buoy  1113  is situated offshore with respect to the breaking wave, one may expect these signal amplitude profiles  1114 ,  1115  to be of moderate amplitude and of sinusoidal waveform, as one would expect from the undulating motion atop shoaling, but non-breaking waves. Note that the output profiles of all the vertical components  1106 ,  1109 ,  1112 ,  1115  of all the accelerometers show a greater extent in the downward direction. This indicates the constant offset produced by the force of gravity, and may be used to determine the relative angle of the buoy accelerometer system to true vertical and horizontal axes. On the other end of the line of buoys, the first buoy  1104  going from the beach in the offshore direction is located onshore from the last breaking wave  1101 . Its accelerometer output amplitude profiles  1105 , and  1106  are indicative of a small, short duration impulse in the vertical direction with greater amplitude and duration in the horizontal axis as the onshore bore and offshore retreat associated with plunging or surging breakers proceeds. Ideally the optimal placement of the turbine system would be in the vicinity of buoy  1107  or buoy  1110  whose accelerometer&#39;s output signal profiles in the horizontal axis  1108  and  1111  respectively indicate greatest magnitude in the likely form of a large impulse with a decay of long duration in the onshore direction as the wave plunges or surges and a linear ramp-up in the offshore direction as it retreats. The vertical components  1109 ,  1112  would also likely exhibit an impulse of large amplitude of only short duration while being lifted by the onshore bore. Of course the output profiles of buoys  1107 ,  1110  would vary from that shown to something more resembling the output profiles from the buoys on the ends, as the location within the surf zone of the breaking waves  1102 ,  1103  varies with time. Statistical and frequency domain analysis could serve to determine the optimal location for extracting energy within the surf zone amongst these two buoys  1107 ,  1110  and will subsequently be expounded upon. While shown in an orientation parallel to the ordinary direction of onshore bore of breaking waves, both this buoy system and particularly the rail system is equally suitable for implementation across an inlet, orthogonal to its tidal bore, or across a river orthogonal to its flow. Thus the buoy and especially the rail system exists for adaptively locating the entire turbine system to an area of optimal flow, regardless of body of water wherein implemented or whether the variation of location of optimal flow velocity is diurnal due to tides or seasonal due to weather patterns. Uses other than the aforementioned alternate uses including removal of the unit from obstructing waterway traffic or removal for facilitated maintenance do not constitute a substantial departure beyond the scope of the present invention. The control algorithm of the complete system including the implementation of the buoy and rail system will be delineated in  FIG. 16  and subsequent paragraphs.  
         [0048]      FIGS. 12, 13 ,  14 , and  15  depict various coupling configurations and energy extraction means from the coaxial fluid coupler or other actuator means through to the output conditioning circuitry of the electric generator.  FIG. 12  shows the fluid coupler  210  having a shaft  1201  that directly couples to the rotor shaft of an AC generator  1200 . The fluid coupler  210  physically occupies the space within the draft area of the shroud  102 , while the coupler shaft  1201  extends into the generator housing  206 . Note that the shaft  1201  in  FIG. 12  is a simplified representation of the coaxial fluid coupler shaft, and in the preferred embodiment would likely also contain slip rings to impart electrical power and control signals to the aforementioned electromechanical means internal to the coupler  210  for adjusting the pitch of the runner blades  211 . In one embodiment, the AC generator  1200  would preferably be an AC induction generator of adequate number of poles such that its synchronous speed, which determines whether the AC machine is operating in its generator or motor region according to its torque-slip curve and is inversely proportional to the number of poles, is well below the average rotational velocity of coaxial fluid coupler  210 , and therefore the AC machine operates with positive slip as a generator. As previously mentioned the ratio of the area of the screen-covered intake  103  to the area orthogonal to flow within the draft section in the shroud  102  that the fluid coupler  210  occupies is directly proportional to the ratio of velocity of the motive fluid approaching the runner blades  211  to the velocity of flow entering the screen-covered intake  103 , and therefore also determines the average rotational velocity of the fluid coupler  210 , and thus also affects the calculation of the required synchronous speed of the generator  1200 . What makes the AC induction generator preferable is its economical, reliable construction and widespread use, rendering this type of generator easily attainable and cost effective. Also, asynchronous AC induction generation requires little additional circuitry in order to apply power directly to the utility power grid. In the case of unavailability of an AC generator of sufficient number of poles for an adequately low synchronous speed to operate with positive slip given the average rotational velocity of the fluid coupler  210 ,  FIG. 13  depicts an AC induction generator  1200  indirectly coupled to the coaxial fluid coupler  210  through the gear system  1300 . The gear system represented by block  1300  in its simplest implementation is that of  FIG. 9  wherein this implementation the actuator shaft  908  is the coupler shaft  1201  and the rotor shaft  902  is that of the AC induction generator  1200 , and the gear system increases the rotational velocity of the rotor shaft with respect to the coupler shaft  1201  as previously described. The gear system would likely occupy space within the generator housing  206  in proximity to the generator  1200 . From the generator  1200  comes two leads  1202  representing the power mains off of the armature coil of the generator  1200 . Though two leads  1202  imply a single-phase machine, this is purely exemplary, and no pre-determination is placed on the number phases of the machine in the preferred embodiment. In order to directly apply the voltage from the AC induction generator  1200  to the utility power grid through wires  1204 ,  1205 , the electrical circuit represented by block  1203  contains a watt-hour meter, and a speed dependent switch that receives an input signal from a velocity transducer sensing the rotation of the coupler shaft  1201  in the generator housing  206 . The velocity transducer output signal would therefore also need to be physically routed along the same path as the leads  1202 , either on its own conductor or modulated upon the armature coil power current. This speed dependent switch affords highest efficiency and protection such as when the coupler shaft has inadequate velocity for positive slip, or there exists a fault condition on either side of the circuit block  1203 , the generator  1200  becomes disconnected from the utility power grid. The circuit block  1203  is likely physically located on land away from the turbine unit, with the leads  1202  routed from the generator  1200 , through slip rings in the columns  209  in the vicinity of the gimbals on the same axis as bearing  107 , through slip rings near bearing  109 , down to the base  116 , out along the rail system  119  to the onshore location of the circuit block  1203 . As with the leads before the circuit block  1203 , though only a pair of wires  1204 ,  1205  are shown implying a single-phase system, this is purely exemplary with no predetermination of the number of phases that may be applied to the utility power grid.  
         [0049]     Alternately, the circuit block  1203  may take the AC voltage produced by the generator  1200  from leads  1202  and full-wave rectify the AC voltage into a DC voltage, then filter and further regulate the voltage and current for optimal power conditioning for application to loads as described in the following paragraphs regarding DC power generation.  
         [0050]      FIG. 14  illustrates an alternate arrangement from the coaxial fluid coupler  210  through to the power output means. Here the simplified representation of the coupler shaft  1201  is shown directly coupled to the rotor of a DC generator  1400 . The DC generator  1400  may be any of available forms of DC generator, including but not limited to a commutated or semiconductor-rectified generator, and preferably with a self-excited shunt field winding configuration chosen for its combined simplicity and relatively constant voltage independent of load current. The DC generator  1400  then produces a speed dependent DC voltage on the leads  1401  and  1402  that feeds the power conditioning circuit block  1403 . The power conditioning performed within the circuit block  1403  could include filtering spurs caused by commutation, and regulating voltage and current for optimally applying the generated power to output means. Regulation would preferably be of the most efficient known variety, in most cases chopped or in other words, switch-mode buck, boost or buck-boost regulation, depending upon the speed voltage of the generator  1400  and the load requirement. A variety of loads may be applied by connection to the leads  1404 ,  1405  depending upon end user needs. Examples of loads could include charging any variety of available chemistries of battery; the leads  1404  and  1405  themselves could terminate as the electrodes in the process of electrolysis of water to produce hydrogen fuel; or the leads  1404  and  1405  could further power a DC motor coupled to a synchronous AC generator directly applied to the utility power grid.  
         [0051]     In the case of the load being the charging batteries, the circuit block  1403  could occupy the physical location of the generator housing  206 , but because the process of battery charging generally requires low-error voltage sensing at the battery terminals and low-error temperature sensing from a thermistor within the cell packaging powered by an accurate reference, it would likely be more feasible and economical to locate the power conditioning circuit block  1403  in proximity of the battery unit to be charged on shore. Therefore the leads  1401 ,  1402  would likely route unconditioned DC power from the generator  1400 , through slip rings in the columns  209  in the vicinity of the gimbals on the same axis as bearing  107 , through slip rings near bearing  109 , down to the base  116 , out along the rail system  119  to the onshore location of the circuit block  1403 .  
         [0052]     Another exemplary load could be the current required to perform electrolysis on water to produce hydrogen fuel. This process achieves a high efficiency due to inherent advantages in the preferred embodiment of the present invention. Seawater is naturally electrolytic thereby reducing chemical processing costs; and advanced electrolysis methods allow for a voltage as little as one and a half to two volts applied across the electrodes, which the generator  1400  in the self-excited shunt field winding configuration can easily provide over a wide range of rotational velocities of the fluid coupler  1201 . In one embodiment, the cavity  202  within the shroud  102 , otherwise vacant to provide buoyancy to the turbine, could also provide the physical volume to store the hydrogen fuel output from the process of electrolysis of water. Given the requirements for such a system for electrolysis, the circuit block  1403  could consist of simply a filter capacitor to smooth the spurs caused by the commutator of the DC machine, and likely a switch-mode buck or in other words, stepdown DC-to-DC converter, perhaps with some form of current regulation, to provide the appropriate voltage to the electrodes  1404 ,  1405  to perform electrolysis. Because this circuit block  1403  is relatively simple and compact, it would most economically occupy an area adjacent to the generator  1400  within the generator housing  206 , with the leads  1404  and  1405  routing conditioned DC power to the electrodes contained within the appropriate sections of the cavity  202  in the shroud  102 , producing hydrogen fuel stored in the cavity  202  generated through electrolysis of seawater admitted into the appropriate section of the cavity  202  in a controlled manner through a filter membrane.  
         [0053]     A third exemplary load for the DC generator  1400  could exist in the form of the leads  1404 ,  1405  attached to a DC motor further coupled to an AC synchronous generator directly applied to the utility power grid. In consideration of this application, the circuit block  1403  would necessarily not only require filtering to smooth the spurs caused by commutation, and voltage regulation to maintain constant speed in the DC motor coupled to the synchronous AC generator, but likely would further require high capacity charge storage devices in the form of a very large capacitor or bank of capacitors or possibly a battery, also in order to maintain constant speed in the DC motor coupled to the synchronous AC generator during periods of reduced rotational velocity in the axial fluid coupler  210 . The complexity and physical volume of such a circuit dictates that the circuit block  1403  is located in the vicinity of the DC motor and AC synchronous generator. As such, the leads  1401 ,  1402  would likely route unconditioned DC power from the generator  1400 , through slip rings in the columns  209  in the vicinity of the gimbals on the same axis as bearing  107 , through slip rings near bearing  109 , down to the base  116 , out along the rail system  119  to the onshore location of the circuit block  1403 .  
         [0054]      FIG. 15  illustrates an auxiliary generator  1500  attached through a system of gears  1300  to an actuator  1506 . The proposed primary provider of mechanical torque for this auxiliary generator  1500  is the rotating sections in the vicinity of the bearing  109 . Gear  1506  rotates while its teeth mesh with a circular rack gear not shown of greater circumference than, and concentric to, the bearing  109 , affixed to the follower brace  120  rotating with respect to the main shaft collar  111 . In this instance the actuator shaft  908  would be coaxial, but not likely concentric, to the main shaft collar  111 , and the gear system  1300  and the auxiliary generator  1500  would also occupy a location affixed within the main shaft collar  111 . This axis of the gimbal is chosen given that the onshore bore and offshore retreat of breaking waves acting upon the rudders and the gimbal would give this axis significant periodic motion, though in other implementations, the other axis of the gimbal may prove prolific in extracting power. As before, the block  1300  represents the system of gears described in  FIG. 9 , the end result is that the auxiliary generator&#39;s  1500  rotor shaft exhibits a higher rotational velocity compared to the follower brace  120 . In the preferred embodiment, the generator  1500  would likely be either an AC induction generator with external semiconductor rectification and velocity-controlled switching or else a DC generator. This auxiliary DC power generated could then be applied to either a separately excited field winding of the main generator or additively coupled to the output of the main generator through means of switch mode circuitry such as coupling in series a secondary winding of a transformer with rectifiers for voltage boosting or coupling in parallel a charge pump circuit for current boosting. Circuit block  1503  and leads  1504 ,  1505  would likely occupy a space within the generator housing  206  in the case of providing current to a separately excited field winding of the main generator, or else the same location as the power conditioning circuitry employed in the above applications. An alternate purpose for this electromechanical assembly exists in case over a long period of use the screen-covered intake  103  gets covered with tenacious debris such as seaweed, the turbine may change orientation such that the face is no longer orthogonal to the streamlines of the motive fluid thereby allowing the motive fluid to wash the debris from the screen-covered intake  103 , simply by reversing the current on leads  1501 ,  1502  of the DC machine such that it then operates as a motor, or to switch-in an AC voltage of amplitude and frequency such that the AC induction machine then operates as a motor to affect this change in orientation.  
         [0055]      FIG. 16  illustrates the overall control of all the components described thus far of the complete gimbal-mounted turbine for adaptively extracting energy from a free flowing motive fluid that continuously changes direction and magnitude of flow. While  FIG. 16  displays a flowchart, which is ordinarily associated with a computer program running in software, the algorithm delineated may be implemented with any combination of hardware or software such as linear or analog circuits or discrete digital circuits or an integrated central processing unit, or a microprocessor. One advantage a central processing unit or microprocessor affords is convenient means to gauge, test, and communicate to a central service logging location the state of any part of the system, including functionality, or fullness of charge of batteries, or hydrogen fuel tanks, etc., using means such as well-defined existing serial protocols or wireless standards. From the start  1600 , the controller is continuously sampling and storing  1601  such variables as the main generator output voltage, denoted Vo, and the output voltages from the accelerometers affixed to the buoys and from there proceeding in four concurrent paths through the flowchart. While not specifically stated in block  1601 , it may be assumed all sampled variables including the signals representing the outputs of the gimbal motion sensors and/or the auxiliary generator are being sampled and stored in a likewise continuous, concurrent manner as implied by the looping arrow exiting only to return to the upper right corner of block  1601 . In the preferred embodiment, this sampling period would have a time resolution necessary to react to and control mechanical processes, ordinarily sampling at approximately a frequency of about a hundred times a second, or a period of about ten milliseconds, with a small deviation allowable possibly due to the convenience of a local non-integer multiple frequency digital clock from which to derive this sampling clock frequency. These samples would then get averaged over a space of five to ten samples, this average representing a single sample in order to reduce the effects of noise. It is reasonable that no control process or adjustment would need to occur, or could efficiently occur for that matter, more often than ten to twenty times a second. Note that the four concurrent paths through the flowchart as well as some of the processes undergone in those paths are implementation specific. Obviously if certain hardware components were omitted, that would then render the associated process obsolete.  
         [0056]     In practically all conceivable embodiments, there would always exist the path that serves to adjust the internal flow vanes  207  and runner blades  211  to optimize internal flow velocity approaching the axial fluid coupler  210  over a range of velocities of the free flowing motive fluid itself external to the turbine shroud  102 . Thus in the flowchart of  FIG. 16 , the path proceeds from the sampling block  1601  to the decision block  1605 , where the instantaneous magnitude of the sampled main generator output voltage, |Vo|, is compared to an upper threshold. This upper threshold would likely equal in excess of one hundred percent of, but less than two times, the rated voltage of the generator. Various types of circuits may perform this comparison through either digital sampling followed by numeric comparison or through analog comparators in effect triggering the DC stepper motors that actuate such adjustments through a voltage feedback loop. Hence, the outcome of this comparison in block  1605  determines whether to throttle up  1608 , or throttle down  1607 , the velocity of the flow through the turbine by adjusting the internal flow vanes  207  and runner blades  211  accordingly. Using means described previously and depicted algorithmically in  FIG. 7 , to throttle up the internal flow velocity, the controller must tighten the pitch of the runner blades  211  to a larger angle with respect to the center axis of the turbine, and to throttle down, the pitch of the runner blades  211  becomes a smaller angle, closer to parallel to the center axis, all while adjusting the angle of incidence of flow with the internal flow vanes  207  appropriately. This algorithm allows the generator to produce a maximum voltage throughout the period of usable flow.  
         [0057]     A similar path through the flowchart exists for controlling the open or closed state of the gate. The gate in the present invention primarily functions in two states, fully open and shut, as opposed to prior art where the gate continuously controlled flow as a means of maintaining synchronous operation over varying heads and loads. In the present invention, the gate closes to inhibit flow to enable the gimbal to rotate without the mechanical constraint of gyroscopic precession, which would otherwise exist due to the angular momentum of the axial fluid coupler  210 . The path through the flowchart that exits block  1601  proceeding to block  1602  portrays the control of the gate. Here the instantaneous magnitude of the voltage output from the main generator |Vo|, is differentiated over time. From block  1602 , the algorithm then proceeds to the decision block  1606  to determine if the derivative with respect to time of |Vo| is practically zero. As shown in block  1606 , the absolute value of the derivative is evaluated since a negative derivative merely implies the rotor is slowing, the absolute value evaluated to be lower than a threshold to account for some inaccuracy due to noise, if so, then implies a maximum or minimum in instantaneous output voltage magnitude. If the comparison finds the output voltage not at a maximum or minimum, it returns, otherwise the next step proceeds to block  1609 , whereby comparing the instantaneous magnitude of the output voltage |Vo| to some threshold determines whether |Vo| is at a maximum or minimum. There it may also sense motion in the gimbal by directly observing the output of its motion sensor or indirectly by sensing the voltage generated by the auxiliary generator mechanically coupled to the associated axis of the gimbal. If the instantaneous output voltage of the main generator is below a threshold at this point, and/or motion is sensed in the gimbal, then the controller undertakes the process to close the gate  1611 . The gate will remain in the closed state  1611  as long as the motion in the gimbal is sensed as depicted by decision block  1613 . Upon gimbal motion ceasing, the gate opens  1615 , and the algorithm returns to the start state  1600 .  
         [0058]     Another path exists based on processing the sampled instantaneous magnitude of the output voltage |Vo| to determine the extent of control processes applied in order to optimally extract energy from a free flowing motive fluid. Proceeding to block  1603 , integration over an interim period is performed to determine the energy extracted during that interim. It is then averaged over the number of samples during that interim period to determine the average power during that period. The interim period would best be defined by a number of samples corresponding to a power of two. First, a number of samples, n, where n is a power of two, can be averaged simply by shifting the binary fixed-point integer sum of n samples of |Vo|, log 2(n) places to the right. Secondly, block  1614  performs calculations based on this variable and on the corresponding output of a Fast Fourier Transform, FFT, which by definition of the FFT algorithm, must be calculated over a number of samples equal to a power of two. The output variable of this averaging process  1603  is then input to update a long term average  1610  and then compared to a low threshold  1612  to determine if power is being extracted properly. If not, the controller proceeds to block  1616 , where the turbine attempts to remove debris obstructing its intake by means previously described. Otherwise if the rail system or the system of accelerometers affixed to buoys is left unimplemented, the algorithm then returns to the start, otherwise it continues in an interaction with the accelerometer system to control the positioning along the rail system as subsequently described.  
         [0059]     While the average power over an interim is being calculated, the output profiles of the accelerometers on buoys are sampled and sorted in a pattern matching algorithm to determine the location of the most recent breaking wave relative to the nearest buoy based on the foregoing discussion of output profile characteristics, while the statistics are gathered to perform a linear spatial frequency analysis to determine the sequence of locations where the waves break  1604 . Whereas all previous blocks of the flowchart of  FIG. 16  could have been performed without a digital processor, the complexity of the calculations performed in block  1604  likely require a digital signal processor. As an example of the linear spatial frequency analysis, much energy at a low frequency at a certain location in time and space indicates many instances of breaking waves are likely to occur in one location or gradually move in one direction, or gradually undulated over a short distance for a given time, where much energy at a high frequency would indicate a large variability in break location for a given time, and thus increased difficulty tracking and diminished returns in energy invested tracking such a sequence of locations of breaking waves. The smallest period of time the frequency domain analysis could be based on is the interim period previously described that preferably spans the minimum time required to identify an instance of a single breaking wave, thus furnishing amplitude data for that breaking wave sample. A number of these periods, or breaking wave samples, can then be accumulated such that the requirement of a power of two samples for performing a Fast Fourier Transform is satisfied, to give a time dependent distribution of location or in other words, a procession, of breaking waves. Here the concern is that the number of sampled breaking waves is great enough that an accurate Fast Fourier Transform may be computed without spanning such a period of time that the natural changes due to tides reduce the repeatability from one procession sequence to the next. While the presumption that over one hour the repeatability of the wave procession provides reasonable tracking, one hour should permit two to four unique sequences of sixty four to two hundred fifty six breaking wave samples computed within an FFT.  
         [0060]     Depending on the outcome of decision block  1612 , if power generation proves greater than a lower limit, the power extracted that correlates to optimal power, or in other words, power extracted during an interim period wherein the buoy accelerometers had identified a plunging or surging breaker occurring in close proximity before the face of the turbine, is compared  1614  to a threshold value, such as the long term power average calculated in block  1610 . Theoretically, a turbine of like embodiment of the present invention, with a face area of one square meter, can extract an average of approximately three horse-power or about two and a quarter kilowatts given the aforementioned breaking conditions of a wave of one meter deep-sea height, and ten second period. If this type of wave is considered average for the place of installation, then occasions when the deep-sea wave height is doubled yield more than double the power output. Block  1614  attempts to determine such occasions that make close tracking of the procession worth the energy expended to do so. For instance, if the energy in the ocean is low that day, then the turbine should spend as little energy as necessary tracking the procession of breaking waves as depicted in block  1618 , just often enough to track the tide, the procession of which could be prerecorded in non-volatile memory as a type of almanac. However, on an occasion where the return on the energy invested makes tracking the procession along the rail system worthwhile, block  1617  suggests as often as every interval, given high amplitudes and high energy in correlated low spatial frequency bins.  
         [0061]     The previously described paths through the flowchart of  FIG. 16  perform mathematical manipulations on the sampled instantaneous magnitude of the output voltage, |Vo| in order to determine an appropriate course of action. The manipulations include differentiation and integration, and it should be known that any of the paths could share the outputs of these mathematical functions in order to improve the overall control algorithm. While not explicitly depicted for sake of clarity in the flow diagram of  FIG. 16 , it may be inferred, and thus any deviation of the algorithm to include the additional use of these function output variables in decision blocks, or for that matter, use of a singular central processor to also concurrently perform these and other control tasks not explicitly depicted, such as, but not limited to: charging batteries; or performing electrolysis; or electronic means of motor speed control; adjusting to changes in load; or stepper displacement; or controlling an array of gimbal-mounted turbines; or logging communications; does not constitute a substantial departure beyond the scope of the present invention.  
         [0062]     From the detailed description above it is manifest that various implementations can use the concepts of the present invention without departing from its scope. Moreover, while the invention has been described with specific reference to certain embodiments, a person of ordinary skill in the art would recognize that significant alterations could be made in form and detail without departing from the spirit and the scope of the invention. The described embodiments are to be considered in all respects as illustrative and not restrictive. It should also be understood that the invention is not limited to the particular embodiments described herein, but is capable of many rearrangements, modifications, omissions, and substitutions without departing from the scope of the invention.  
         [0063]     Thus, a gimbal-mounted hydroelectric turbine for adaptively extracting energy from a free flowing motive fluid that continuously changes direction and magnitude of flow has been described.