Patent Publication Number: US-2011056424-A1

Title: Aquatic device

Description:
This application is a Continuation of U.S. Ser. No. 12/144,393, filed 23 Jun. 2008, which is a Continuation-in-Part of PCT/AU2006/001862, filed 7 Dec. 2006, which claims benefit of Serial No. 2005907264, filed 23 Dec. 2005 in Australia and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to an aquatic device, and more particularly to an aquatic device for providing maneuverability to a user moving in water. 
     BACKGROUND OF THE INVENTION 
     There have been various proposals for maneuvering a person through a body of water. The proposals typically involve devices for propelling a user through a body of water in a manner which allows the user to travel either along the water surface or under water. Such devices have recreational applications and are also particularly suitable for underwater pursuits such as diving and snorkeling. 
     One known type of such device is disclosed in U.S. Pat. No. 5,558,551 which involves a planar member adapted to be towed behind a boat by way of a tow line to which the planar member is attached. The planar member incorporates handle apertures by means of which a user can grasp the planar member to be towed along. The planar member can be articulated by the user to provide some limited depth and steering control within the water while being towed behind the boat. 
     While articulation of the planar member does provide some steering and depth control, there can be a significant lag between articulation of the planar member and a resultant directional change in the movement of the user. Accordingly, there can be a lack of responsiveness and subtle changes in direction can be difficult to achieve. Further, it may be necessary for the user to rotate his or her body in order to achieve articulation of the planar member for directional control. 
     An aquatic device which is propelled by a user (rather than being towed) is a swimming kick board commonly used to improve the kicking action of swimmers. Such an aquatic device offers limited direction control through tilting of the board and is generally not suitable for use underwater. 
     It is against this background that the present invention has been developed. 
     The above discussion of the background to the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge in Australia as at the priority date of the application. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention there is provided an aquatic device comprising handle means adapted to be grasped by a user, and two control elements moveable one with respect to the other to manoeuvre the aquatic device. 
     The aquatic device may be maneuvered through movement of the control devices to provide directional control or variation to the orientation of the device (and hence to the user holding the device). The directional control may include both steering and depth control (including at least dissension and ascension). 
     Preferably, the control elements comprise fins. 
     Each control element may comprise a leading end, a trailing end, and upper and lower control surfaces therebetween. The upper and lower control surfaces may taper inwardly with respect to each other in the direction towards the trailing end. The leading end may be profiled to facilitate movement through the water. The leading end may, for example, present a rounded profile or alternatively be of angular configuration incorporating a leading edge. 
     Each control element may be configured to guide water flow along the control surfaces. Specifically, each control element may comprise protrusions extending from either or both of the upper and lower control surfaces. The protrusions may comprise an inner rib extending between the leading end and the trailing end of each control element. The protrusions may further comprise an outer rib extending between the leading end and the trailing end of each control element. 
     The outer rib is preferably located at an outer side edge of the control element. The ribs outer rib may be arcuate in cross-sectional profile. Further, the outer rib may be configured to taper inwardly in the forward direction and merge with the leading end of the control element. 
     The inner and outer ribs provide flow control elements for guiding oncoming water with respect to the upper and lower control surfaces, impeding spillage of water sidewardly prior to reaching the trailing end. Further, the protrusions which provide the outer ribs may function as a safety edge along the at the outer side edges of the control elements 
     Preferably, the handle means are operably connected to the two fins whereby the user can manually control movement of the control elements one with respect to the other. 
     Preferably, the control elements are pivotally moveable with respect to each other. 
     Preferably, the control elements are movable about a common pivot axis. 
     Preferably, the common axis is generally transverse to the direction of travel. 
     Preferably, the pivot axis is generally horizontal when the aquatic device is travelling in a generally horizontal straight line direction. 
     Preferably, the handle means comprises two handles each connected to a respective one of the control elements. 
     In one arrangement, the two control elements may be disposed adjacent each other and the two handles located laterally outwardly thereof. In other arrangement, the two handles may be disposed adjacent each other and the two control elements located laterally outwardly thereof. 
     Preferably, the relative positions of the handles with respect to the control elements are selectively variable. In other words, the configuration of the aquatic device can be changed between the arrangement in which the two control elements are disposed adjacent each other and the two handles located laterally outwardly thereof, and the arrangement in which the two handles are disposed adjacent each other and the two control elements located laterally outwardly thereof. 
     Preferably, the aquatic device further comprises an axle wherein the control elements and the respective handles connected thereto are rotatably supported on the axle. In one arrangement, the axle may provide a spindle upon which the control elements and the respective handles pivot. In another arrangement, the axle may provide a spindle pivotally interconnecting the control elements and the respective handles 
     The control elements and the handles may be removable from the axle. This may allow for disassembly for ease of transport and storage. Further is may facilitate the selective variation of the relative positions of the handles with respect to the control elements. 
     The aquatic device according to the invention may be propelled through the water in any appropriate way. In one arrangement, the aquatic device may be adapted to be towed through the water. In another arrangement, the aquatic device may be propelled through the water by the user. In still another arrangement, the aquatic device may have an on-board propulsion system. 
     Where the aquatic device is adapted to be towed through the water by way of a tow line, the device preferably has a connection means for attachment to the tow line. The connection means preferably provides for detachable connection to the tow line. 
     Preferably, the connection means is associated with the axle. In one arrangement, the connection means may comprise a bridle having sections extending from each end of the axle. In another arrangement, the connection means may comprise a coupling on the axle, preferably centrally located such there is a respective control element and handle to each side thereof. The aquatic device may be fitted with both connection arrangements in order to provide the user with a choice. 
     According to a further aspect of the invention there is provided an aquatic device for towing a user through a body of water, the aquatic device comprising handle means adapted to be grasped by the user, and two control elements moveable one with respect to the other for directional control of the device. 
     According to a still further aspect of the invention there is provided an aquatic device comprising handle means adapted to be grasped by a user to apply propulsion thereto, and two control elements moveable one with respect to the other for maneuvering the aquatic device while being propelled by the user, the handle means being operably connected to the two control elements whereby the user can manually control movement of the control elements one with respect to the other. 
     According to a still further aspect of the invention there is provided a swimming aid comprising handle means adapted to be grasped by a user, and two control elements moveable one with respect to the other to manoeuvre the swimming aid, the handle means being operably connected to the two control elements whereby the user can manually control movement of the control elements one with respect to the other. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be better understood by reference to the following description of several specific embodiments thereof as shown in the accompanying drawings in which: 
         FIG. 1  is a schematic perspective view of an aquatic device according to a first embodiment in use; 
         FIG. 2  is a further schematic perspective view of the aquatic device in use; 
         FIG. 3  is a schematic perspective view of the aquatic device in a disassembled condition; 
         FIG. 4  is a schematic perspective view of the aquatic device assembled in a first configuration and having a bridle connection to a tow line; 
         FIG. 5  is a schematic perspective view of the aquatic device assembled in a second configuration and having the bridle connection to the tow line; 
         FIG. 6  is a schematic perspective view of the aquatic device in the configuration of  FIG. 5  but having a central connection to the tow line; 
         FIG. 7  is a schematic perspective view illustrating the aquatic device in use towing a user, with the aquatic device being in a condition to descend; 
         FIG. 8  is a schematic perspective view illustrating the aquatic device in use towing a user, with the aquatic device being in a condition to ascend; 
         FIG. 9  is a schematic perspective view illustrating the aquatic device in use towing a user, with the aquatic device being in a condition to rotate anti-clockwise or alternatively perform a left turn; 
         FIG. 10  is a view similar to  FIG. 9 , with exception that the aquatic device is in a condition to rotate clockwise or alternatively perform a right turn; 
         FIG. 11  is a front view showing rotation of the aquatic device when in the condition shown in  FIG. 9 ; 
         FIG. 12  is a front view showing rotation of the aquatic device when in the condition shown in  FIG. 10 ; 
         FIG. 13  is a schematic perspective view of an aquatic device according to a second embodiment in use; 
         FIG. 14  is a view similar to  FIG. 13  except that the aquatic device is shown in a condition to descend; 
         FIG. 15  is a further schematic perspective view of the aquatic device according to the second embodiment in use; 
         FIG. 16  is a schematic perspective view of an aquatic device according to a third embodiment; 
         FIG. 17  is a perspective view of an aquatic device according to a fourth embodiment; 
         FIG. 18  is a side view of the aquatic device according to the fourth embodiment; 
         FIG. 19  is front view of the aquatic device according to according to the fourth embodiment; 
         FIG. 20  is perspective of the aquatic device according to according to the fourth embodiment, with one of the fins rotated; 
         FIG. 21  is a perspective view of the aquatic device according to the fourth embodiment; 
         FIG. 22  is a perspective view of the aquatic device according to the fourth embodiment in use; 
         FIG. 23  is a cross-sectional view of the aquatic device according to the fourth embodiment; 
         FIG. 24  is a perspective view of a portion of the aquatic device according to the fourth embodiment providing one of the handles; 
         FIG. 25  is a cross-sectional view of the central coupling portion of the aquatic device according to the fourth embodiment; 
         FIG. 26  is an exploded view of the central coupling portion; 
         FIG. 27  is a perspective view of an element forming part of the central coupling portion; 
         FIG. 28  is a side view of the element of  FIG. 27 ; 
         FIG. 29  is an end view of the element of  FIG. 27   FIG. 30  is a perspective view of the aquatic device according to a fifth embodiment; 
         FIG. 31  is a perspective view from the front of a fin of the aquatic device according to the fifth embodiment; 
         FIG. 32  is a perspective view from the rear of the fin of  FIG. 31 ; and 
         FIG. 33  is a plan view of the fin of  FIG. 31 . 
     
    
    
     BEST MODE(S) FOR CARRYING OUT THE INVENTION 
     Referring to  FIGS. 1 to 12  of the drawings, there is shown an aquatic device  10  according to the first embodiment for towing a user  11  through a body of water  13 . The aquatic device  10  is adapted to be towed behind a boat  15  by way of a tow line  17 , and the user  11  may travel on or under the water. 
     The aquatic device  10  comprises handle means  20  adapted to be grasped by the user  11  with arms extending forwardly, and two fins  21 ,  22  pivotally moveable with respect to each other. 
     The aquatic device  10  further comprises an axle  23  onto which the handle means  20  and the fins  21 ,  22  are pivotally mounted. In the arrangement shown the axle  23  is tubular, comprising a rigid tube of any appropriate material such as aluminium. 
     The handle means  20  comprises two handles  24  each connected to a respective one of the fins  21 ,  22 . With this arrangement, the combination of each handle  24  and its respective fin  21 ,  22  comprises a control unit  25 . The control units are rotatably mounted on the axle  23 . 
     Each handle  24  comprises a tubular shaft  26  and a hand grip  27  provided on the outer side of the shaft. The tubular shaft  26  is rotatably mounted on the axle  23 . The hand grip  27  is configured to offer a comfortable grip for the user. 
     Each fin  21 ,  22  comprises a fin body  28  having an upper control surface  29 , a lower control surface  30 , a leading end  31  and trailing end  32 . The upper and lower control surfaces  29 ,  30  taper towards each other in the direction towards the trailing end  32 . The fin body  28  is of hollow construction with an open interior  34  for ingress of water to reduce buoyancy effects. In the arrangement shown, the leading end  31  is configured to present a rounded profile to oncoming water as the aquatic device  10  is propelled through the water. 
     Each fin  21 ,  22  incorporates a sleeve portion  35  having a hole  36  which extends crosswise through the body  28  adjacent the leading end  31  and which is co-axial with the tubular shaft  26 . With this arrangement, the fins  21 ,  22  can be rotatably mounted on the axle  23  by virtue of the axle being received within the hole  36 . 
     The tubular shaft  26  of each handle  24  is connected to the respective fin  21 ,  22  such that rotation of the handle  24  causes rotation of the respective fin. 
     The control units  25  can be positioned on the axle  23  selectively in either one of two arrangements. In the first arrangement, which is best seen in  FIG. 4 , the control units  25  are oriented such that the two fins  21 ,  22  are disposed adjacent each other and the two handles  24  are located laterally outwardly thereof adjacent the ends of the axle  23 . In the second arrangement, which is best seen in  FIG. 5 , the control units  25  are oriented such that the two handles  24  are disposed adjacent each other and the two fins  21 ,  22  located laterally outwardly thereof adjacent the ends of the axle  23 . The first arrangement is particularly suitable for larger children and adults who may have a preference for a wider grip on the aquatic device  10  as it is likely to be more comfortable. The second arrangement is particularly suitable for small children whose grip might not be able to span the distance between the handles  24  when they are not disposed adjacent each other. 
     A spacer  37  is provided on the axle  23  between the two control units  25 . End fittings  41  are provided on the axles  23  in order to retain the control units  25  in position thereon. The end fittings  41  are removable to facilitate disassembly of the aquatic device  10  or to alter the configuration of the control units  25  on the axles  23 . Spacers  42  are provided between each end fitting  41  and the adjacent control unit  25 . 
     A bridle  43  is provided on the axle  23  for attachment to the tow line  17 . The bridle  43  has two bridle sections  45  which extend from the ends of the axle  23  to a common coupling  47  releasably attachable to the tow line  17 . In the arrangement shown, the bridle  43  comprises a loop  49  in the form of a length of rope or cable extending through the tubular axle  23  and connected at its ends to the common coupling  47 . The loop  49  may be constrained in any appropriate way to prevent it from sliding within the axle  23 . 
     The central spacer  37  may incorporate a coupling  51  providing an attachment point to which the tow line  17  can be connected, if desired, in order to offer an alternative connection to the tow line  17  to that provided by the bridle  43 . Such an arrangement is illustrated in  FIG. 6 . If the coupling  51  is used to provide the connection to the tow line  37 , the bridle  43  can be removed from the axle  23 . 
     Operation of the aquatic device  10  according to the first embodiment will now be described. The aquatic device  10  is coupled to the tow line  17  in the manner described so that it can be towed behind the boat  15  with the user  11  holding the handles  24  at the hand grips  27  with arms extending forwardly. In this way, the user  11  can be towed behind the aquatic device  10  as it is pulled through the water  13  by the boat  15 . 
     The user  11  is able to manoeuvre the aquatic device  10  by turning the handles  24  to move the fins  21 ,  22 . If the user wishes to travel in a straight-line direction, the two fins  21 ,  22  are positioned in alignment with each other and also in general alignment with the direction of travel, as illustrated in  FIG. 1 . Where the user  11  wishes to descend (for example to perform a dive), the user  11  merely rotates both fins  21 ,  22  upwardly, as shown in  FIG. 7 . Similarly, where the user  11  wishes to ascend, he or she merely rotates both fins  21 ,  22  downwardly as illustrated in  FIG. 8 . 
     The user  11  may in certain circumstance vary his or her orientation, and in other circumstances possibly achieve some steering control, by rotating one fin  21 ,  22  relative to the other, as illustrated in  FIGS. 9 and 10 . In  FIG. 9 , the right fin  22  is shown rotated downwardly and the left fin  21  is shown rotated upwardly, thereby causing the aquatic device  10  to either rotate in an anti-clockwise direction (with respect to the direction of travel) as indicated by arrow  61  or alternatively perform a left turn (with respect to the direction of travel) as indicated by arrow  62 . In  FIG. 10 , the left fin  21  is shown rotated downwardly and the right fin  22  is shown rotated upwardly, thereby causing the aquatic device  10  to either rotate in a clockwise direction (with respect to the direction of travel) as indicated by arrow  63  or alternatively perform a right turn (with respect to the direction of travel) as indicated by arrow  64 .  FIG. 11  illustrates schematically rotation of the aquatic device  10  and the user  11  when the fins  21 ,  22  are in the condition shown in  FIG. 9 . Similarly,  FIG. 12  illustrates schematically rotation of the aquatic device  10  and the user  11  when the fins  21 ,  22  are in the condition shown in  FIG. 10 . 
     Whether the aquatic device rotates or performs a turn (or indeed perhaps maneuvers in a manner involving both rotation and a turn) may depend on various factors including the depth at which the device is operating and the speed at which it is being towed. 
     There may be provision for tethering the aquatic device  10  to the user  11  to allow the user to temporarily release the handles  24  without losing access to the aquatic device. This may be particularly suitable in circumstances where the user has a need to use his or her hands for other purposes, such as for collecting materials or inspecting underwater objects. Such tethering can be achieved in any suitable way, such a with as flexible tether line connected between the user and the aquatic device. With such an arrangement, the user could release the aquatic device  10  to free his or her hands for other purposes and could subsequently retrieve the aquatic device by hauling in the tether line. 
     The aquatic device  10  may also have provision for fitting various accessory devices, such as an underwater lighting system and holders for equipment (such as tools and other devices). Lights could, for example, be fitted onto the fins  21 ,  22 . 
     In the first embodiment, the aquatic device  10  is configured to be propelled by being towed through the water. Referring now to  FIGS. 13 to 15 , there is shown an aquatic device  10  according to a second embodiment which is adapted to be propelled by the user  11 . The aquatic device  10  according to the second embodiment can merely be the aquatic device  10  according to the first embodiment but configured differently. The ability to configure the aquatic device  10  in such different ways is particularly advantageous as it provides various options regarding the manner in which the aquatic device can be used. In the arrangement shown, the different configuration involves removal of the bridle  43 , as there is no need for a connection to a tow line 
     In this second embodiment, the aquatic device  10  is propelled by the user  11 . In the arrangement shown, the user  11  is wearing flippers  12  to generate propulsion in the water. The user  11  in effect pushes the aquatic device  10  through the water, using it for maneuvering purposes. The user  11  is able to achieve depth and steering control by operating the aquatic device to manipulate the fins  21 ,  22  in a manner similar to that described in relation to the first embodiment. Because the aquatic device  10  is not being towed, it is likely that the user would be able to turn through a full circle should that be desired. When using the aquatic device according to this embodiment, the user may find it necessary to wear a weight-belt in order to overcome buoyancy effects. 
     Referring now to  FIG. 16 , there is shown an aquatic device according to a third embodiment. This third embodiment is similar in many respects to the second embodiment and so like reference numerals are used to denote corresponding parts. In this embodiment, the fins  21 ,  22  are of a closed construction to exclude the ingress of water. With this construction, the fins  21 ,  22  can be either buoyant or non-buoyant, according to the material or materials from which they are constructed. Further, the leading end  31  is configured to present a leading edge  31   a  to the oncoming water as the aquatic device is moved through the water. 
     Referring to  FIGS. 17 to 29  of the drawings, there is shown an aquatic device  140  according to a fourth embodiment. In the arrangement shown, the aquatic device  140  is intended to be propelled by a user  190 , as shown in  FIG. 22 . However, it should be understood that the aquatic device  140  could be adapted to be towed in the manner of the first embodiment. 
     The aquatic device  140  comprises handle means  141  adapted to be grasped by the user  190  with arms extending forwardly, and two control elements such as fins  144 ,  145  pivotally moveable with respect to each other. 
     The handle means  141  comprises two handles  142  interconnected by a rotatable coupling  143 . 
     The coupling  143  provides an axle  146  onto which the handles  142  are pivotally mounted. 
     Each fin  144 ,  145  comprises a fin body  152  having an upper control surface  156 , a lower control surface  160 , a leading end  164 , a trailing end  168 , an outer side edge  165  and an inner side edge  167 . The upper and lower control surfaces  156  and  158  taper towards each other in the direction towards the trailing end  168 . In the arrangement shown, the leading ends  164  are hydrodynamically configured to present an edge profile to oncoming water as the aquatic device  140  is propelled through the water. The edge profile at the leading ends  164  is rounded in the embodiment. 
     Referring to  FIG. 23 , each fin  144 ,  145  incorporates a sleeve portion  172  located at its leading inner corner for mounting of the fins  144 , 155  onto the handle means  141  via a male portion  174  located at an end of each handle  142 . The fins  144 ,  145  are releasably attached to the handle means  141  so they can be removed to facilitate disassembly of the aquatic device  140  or to alter the configuration of the aquatic device by locating different type of fins  144 , 145 . 
     With this arrangement, the combination of each handle  142  and its respective fin  144 ,  145  comprises a control unit  180 . As shown in  FIG. 24 , each handle  142  comprises a hand grip  182  which is configured to offer a comfortable grip for the user. 
     Fins  144  and  145  are configured with rounded corners  184  and rounded leading ends  160  and trailing ends  164  (see  FIG. 18 ) to provide safety edges that are not sharp and thus not likely to harm the user  190  or persons close to the user while the aquatic device is being used. 
     As shown in  FIGS. 17 to 20 , the fins  144 ,  145  are configured to guide water along the control surfaces  156 ,  160 . Specifically, each fin  144 ,  145  comprises protrusions  186 ,  188  that protrude from the upper and lower control surfaces  156 ,  160 . Protrusions  186  each comprise an inner rib  187  extending from adjacent the sleeve portion  172  to the trailing end  168 , inwardly of the inner side edge  167 . Protrusions  188  each comprise an outer rib  189  at the outer side edge  165 , extending from the leading end  164  to the trailing end  168 . The ribs  189  are arcuate in cross-sectional profile, as shown in  FIG. 19 . Further, the ribs  189  are configured to taper inwardly in the forward direction and merge with the leading end  160  of the fin, as best seen in  FIGS. 20 and 23 . 
     The ribs  187 ,  189  provide flow control elements for guiding oncoming water over the upper and lower control surfaces  156 ,  160  of the fins  144 , 145 , impeding spillage of water sidewardly prior to reaching the trailing end  168  of the fins. 
     All edges of protrusions  186  and  188  are rounded to avoid injury of the user or persons close to the user while the aquatic device is being used. Further, the protrusions  188  which provide the outer ribs  189  function as a safety edge along the at the outer side edges  165  of the fins. 
     The control units  180  are rotatably mounted on the axle  146  and for this purpose the opposite end of the handle means  141  comprises a sleeve portion  176  (see  FIG. 24 ) for mounting the handle means  141  rotatably onto the axle  146  via male portions  206  located at each end of axle  146  (see  FIG. 26 ). 
       FIGS. 25 to 29  show the axle  146  and the elements that comprise it. In the arrangement shown, the axle  146  is tubular and comprises a centre element  194  having an irregular outer surface  148  and two ends  150  onto which the handle means  141  are attached. 
     The rotatable coupling  143  which provides the axle  146  comprises two inner coupling portions  202  interconnected for rotational one relative to the other by a hinge pin  198 . An outer coupling sleeve surrounds the two coupling portions and serves to retain the assembly together. 
     Each inner coupling portion  202  comprises a shank section  204  at one end, a spigot section  206  at the other end, and an intermediate section  207  comprising a boss and incorporates a gripping formation  216 . The shank section  204  incorporates a bore  205  into which the hinge pin  198  is rotatably received. 
     The coupling sleeve  196  is of resilient construction to permit relative rotational movement (albeit to a limited extent) between the handles  142 . In the illustrated arrangement, the coupling sleeve is formed of a resiliently flexible plastics material and has lateral ribbing on the outer surface thereof to enhance its flexibility. 
     The ends of the coupling sleeve  196  are received on the bosses  214  of the inner coupling portions  202  and clampingly retained thereon by clamping rings  218 . 
     With this arrangement, the coupling sleeve  196  retain the assembly of the two inner coupling portions  202  together with the hinge pin  198  extending therebetween, while allowing limited pivotal movement of one inner coupling portion  202  relative to the other (thereby accommodating relative rotational movement between the two handles  142  and the fins connected thereto). Further the outer coupling sleeve  196  seals the assembly against the ingress of water and foreign matter such as sand and grit. 
     Each handle  142  comprises a body  171  having a central portion  173  defining the hand grip  182 . The handle body  171  has an outer end configured as a spigot  174  for connection to the sleeve portion  172  of the respective fin, and an inner end configured as a socket  176  to receive the spigot section  206  of one of the inner coupling portions  202 . A locking mechanism  208  is provided for retaining the spigot section  206  in the socket  176   
     In this fourth embodiment, the aquatic device  141  is propelled by the user  190  (see  FIG. 22 ) thus acting as a swimming aid. In the arrangement shown, the user  190  is wearing flippers  192  to generate propulsion in the water. The user  190  in effect pushes the aquatic device  190  through the water, using it for maneuvering purposes. The user  190  is able to achieve depth and steering control by operating the aquatic device to manipulate the fins  144 ,  145  in a manner similar to that described in relation to the first embodiment. If the aquatic device  190  is not being towed, it is likely that the user would be able to turn through a full circle should that be desired. 
     Referring now to  FIGS. 31 to 33 , there is shown an aquatic device according to a fifth embodiment. The aquatic device according to this fifth embodiment is similar in many respects to the fourth embodiment and so corresponding reference numerals are used to identify corresponding parts. In this fifth embodiment, each rib  189  is configured to extend along the outer side edge  165  and at least partly along the leading end  160  of the fin body  152  to ultimately merge therewith. Each rib  189  is configured to ensure that the hydrodynamics of the respective fin are not compromised. 
     From the foregoing, it is evident that the present embodiments each provide a simple yet highly effect aquatic device which can be easily operated by a user in order to provide maneuverability through the water. 
     It should be appreciated that the scope of the invention is not limited to the scope of the embodiments described. For example, in the first embodiment described, the aquatic device  10  is adapted to be towed behind a boat. Other towing arrangements may, of course, be utilised; for example, an overhead cable towing system, a land-based towing system or simply some other person manually pulling the aquatic device along. 
     Further, in an alternative arrangement, the aquatic device may incorporate an on-board propulsion system. 
     Throughout the specification, unless the context requires otherwise, the word “comprise” or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.