Patent Publication Number: US-2011057400-A1

Title: Wheeled platform apparatus and method for use with wheeled footwear

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Pursuant to 35 U.S.C. §119, this application claims priority to and the benefit of, and hereby incorporates by reference for all purposes, U.S. Provisional Patent Application Ser. No. 61/276,214, entitled Wheeled Platform and Method for use with Wheeled Footwear, naming Ryan Daniel Wills as inventor, and filed Sep. 9, 2009; U.S. Provisional Patent Application Ser. No. 61/279,489, entitled Wheeled Platform Apparatus and Method for use with Wheeled Footwear, naming Ryan Daniel Wills as inventor, and filed Oct. 21, 2009; and U.S. Provisional Patent Application Ser. No. 61/399,190, entitled Wheeled Platform Apparatus and Method for use with Wheeled Footwear, naming Ryan Daniel Wills as inventor, and filed Jul. 7, 2010. 
    
    
     TECHNICAL FIELD 
     This invention relates in general to the field of active sports and more particularly to a wheeled platform co-operable with wheeled footwear, including a wheel in the heel (“heeling”) apparatus or skate. 
     BACKGROUND 
     Active sports often include skateboards and wheeled apparatuses. Some individuals, however, desire more functionality and versatility than provided by conventional skateboards and wheeled apparatuses. 
     SUMMARY 
     A wheeled platform apparatus is provided that includes a top surface, a bottom surface, at least two wheels extending at least partially through the bottom surface, and may further include an attachment structure or mechanism positioned adjacent or below the top surface for mating with non-wheeled or wheeled footwear, including a heeling apparatus, quad skate, inline skate, external wheel assembly, or other wheeled skate, or a user&#39;s bare foot. 
     Other technical advantages are readily apparent to one skilled in the art from the following figures and description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts, in which: 
         FIG. 1  is a side view that illustrates a heeling apparatus implemented using an athletic shoe according to one embodiment of the present invention; 
         FIGS. 2A and 2B  are bottom views that illustrate two embodiments of a sole of the heeling apparatus with openings in the sole; 
         FIGS. 3A and 3B  are bottom views of the two embodiments of the sole as shown in  FIGS. 2A and 2B  and illustrate a wheel in each of the openings of the soles; 
         FIG. 4  is a perspective view that illustrates a wheel rotatably mounted to an axle, which also may be referred to as a wheel/axle assembly, for use in a wheel assembly according to one embodiment of the present invention; 
         FIG. 5  is a perspective view that illustrates a mounting structure for use with a wheel rotatably mounted to an axle, as illustrated in  FIG. 4 , to form a wheel assembly; 
         FIG. 6  is a bottom view that illustrates a wheel assembly that includes the wheel rotatably mounted on the axle as shown in  FIG. 4  and the mounting structure of  FIG. 5 ; 
         FIG. 7  is a side view that illustrates the wheel assembly positioned above and through the opening in a footwear to form a heeling apparatus; 
         FIGS. 8A ,  8 B,  8 C, and  8 D are profile views of various wheels that illustrate the surface profile of these wheels that may used in various embodiments of the present invention; 
         FIG. 9  is a perspective view that illustrates a mounting structure of another embodiment for use in a wheel assembly of a heeling apparatus; 
         FIG. 10  is a perspective view that illustrates a wheel assembly that uses yet another embodiment for use in a heeling apparatus; 
         FIG. 11  is a side, partial cutaway view that illustrates one embodiment of a heeling apparatus that illustrates the wheel assembly provided in the sole of the heeling apparatus and the opening in the sole not extending completely through the sole; 
         FIG. 12  is a side view of another embodiment that illustrates the heeling apparatus of the present invention with a removable wheel cover positioned to cover the wheel and the opening in the sole; 
         FIG. 13  is a bottom view that illustrates another embodiment of the present invention with a spherical ball serving as a wheel and positioned in a mounting structure in an opening in the heel portion of the sole; 
         FIG. 14  is a perspective view that illustrates a “heeler” using the present invention to “heel”; 
         FIG. 15  is a perspective view that illustrates a wheel rotatably mounted to an axle, which also may be referred to as a wheel/axle assembly, similar to  FIG. 4 ; 
         FIG. 16  is a cutaway view that illustrates a collapsible axle of the wheel/axle assembly of  FIG. 15  implemented as a spring-loaded collapsible axle; 
         FIG. 17  is a perspective view that illustrates another mounting structure for use with the wheel/axle assembly and the collapsible axle, as illustrated in  FIG. 15  and  FIG. 16 , to form a wheel assembly; 
         FIG. 18  is a side, cutaway view that illustrates a wheel assembly positioned through an opening in a sole that illustrates one embodiment of an axle that couples to the mounting structure to provide a retractable wheel using an assembly that may be referred to as a king pin arrangement; 
         FIG. 19  is a bottom view that illustrates the wheel assembly of  FIG. 18  that further illustrates the dual king pin arrangement; 
         FIG. 20  is a side view that illustrates one member of the mounting structure that further illustrates the coupling of the axle to the mounting structure using the dual king pin arrangement; 
         FIG. 21  is a breakaway and perspective view that illustrates a two piece wheel that includes an inner core and an outer tire and that may be used in the present invention; 
         FIG. 22A  is a side, isometric view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 22B  is a side, isometric view that illustrates one embodiment of a wheeled platform apparatus with no attachment structure; 
         FIG. 23  is a side view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 24  is a top view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 25  is a top, isometric view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 26  is a front, isometric view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 27  is a rear, isometric view that illustrates one embodiment of a wheeled platform apparatus with an attachment structure; 
         FIG. 28  is a front view that illustrates one embodiment of a wheeled platform apparatus interfaced with a footwear; 
         FIGS. 29A ,  29 B,  29 C, and  29 D are side views that illustrate embodiments of a wheeled platform apparatus with a heeling apparatus, quad skate, inline skate, and external wheel assembly, respectively, positioned behind and in contact with the back of the wheeled platform apparatus; 
         FIG. 29E  is a side view that illustrates a one embodiment of a wheeled platform apparatus with a heeling apparatus, with elevated forefoot, positioned at least partially behind the wheeled platform apparatus; 
         FIGS. 30A ,  30 B,  30 C, and  30 D are side views that illustrate one embodiment of a user with one foot positioned on the wheeled platform apparatus and the remaining foot configured with a heeling apparatus, quad skate, inline skate, and external wheel assembly, respectively; 
         FIG. 31  is a top view that illustrates one embodiment of a wheeled platform apparatus with an axle attachment structure; 
         FIG. 32  is a side, isometric view that illustrates one embodiment of a wheeled platform apparatus with a wheel attachment structure; 
         FIG. 33  is a side isometric view that illustrates one embodiment of a wheeled platform apparatus with an at least partially recessed wheel attachment structure; 
         FIG. 34  is a side, isometric view that illustrates one embodiment of a wheeled platform apparatus with a removable deckplate and an attachment structure; 
         FIG. 35  is a side view that illustrates one embodiment of a wheeled platform apparatus with a removable deckplate and an attachment structure; 
         FIG. 36A  is a side isometric view that illustrates one embodiment of a wheeled platform apparatus with a removable deckplate and a removable deckplate locking structure; 
         FIG. 36B  is a top view that illustrates one embodiment of a wheeled platform apparatus with a removable deckplate and a removable deckplate locking structure; 
         FIG. 37  is a side isometric view that illustrates one embodiment of a wheeled platform apparatus with a removable deckplate and a removable deckplate fastener; 
         FIG. 38  is a breakaway and perspective view that illustrates an embodiment of a wheeled platform apparatus with a removable deckplate, attachment structure, axle structure, fasteners, tensioner, recess, mid-chassis, and a platform; 
         FIG. 39A  is a perspective view that illustrates an embodiment of the attachment structure illustrating a first fastener opening, a sleeve-like opening, and a tensioner opening; 
         FIG. 39B  is a side-view that illustrates an embodiment of an attachment structure illustrating a sleeve-like opening and a projection; 
         FIG. 39C  is a bottom-view that illustrates an embodiment of an attachment structure illustrating first and second fastener openings, a projection, and a sleeve-like opening; 
         FIG. 40A  is a rear perspective view that illustrates an embodiment of a mid-chassis with a recess for storing objects, such as axle structures; 
         FIG. 40B  is a top view that illustrates an embodiment of a deckplate; 
         FIG. 40C  is a rear perspective view that illustrates an embodiment of a mid-chassis with a recess for storing objects, such as axle structures; 
         FIG. 41A  is a front perspective view that illustrates an embodiment of a strap coupled to a mid-chassis by a deckplate; 
         FIG. 41B  is a side perspective view that illustrates an embodiment of a strap coupled to a mid-chassis by a deckplate; 
         FIG. 41C  is a perspective view that illustrates an embodiment of a strap positioned over the recess of a mid-chassis; 
         FIG. 41D  is a perspective view that illustrates an embodiment of a deckplate placed over the mid-chassis with a strap positioned therebetween; 
         FIG. 41E  is a perspective view that illustrates an embodiment of a deckplate placed over a mid-chassis, having a recess for storing objects, with a strap positioned therebetween; 
         FIG. 41F  is a perspective view that illustrates an embodiment of a wheeled platform apparatus having a strap attached thereto and positioned around a user&#39;s foot; 
         FIG. 42  is a side view that illustrates an embodiment of a wheeled platform apparatus with the forefoot of a heeling apparatus positioned in contact with the surface as a brake; 
         FIG. 43  is a side view that illustrates an embodiment of a wheeled platform apparatus with the heel of a heeling apparatus positioned in contact with the surface as a brake; 
         FIG. 44  is a perspective view that illustrates an embodiment of an attachment structure capable of mounting at an angle offset from the longitudinal centerline of the wheeled platform apparatus; 
         FIG. 45  is a bottom view that illustrates an embodiment of a heeling apparatus having a recess for receiving a wheel assembly or an attachment structure; 
         FIG. 46A  is a perspective view that illustrates an embodiment of a deckplate being removably mounted to a wheeled platform apparatus; 
         FIG. 46B  is a perspective view that illustrates an embodiment of a deckplate being removed from a wheeled platform apparatus; 
         FIG. 47  is a bottom view that illustrates an embodiment of a wheeled platform apparatus with a removable wheel assembly; 
         FIG. 48  is a perspective view that illustrates an embodiment of a heeling apparatus being removably mounted to a wheeled platform apparatus using an attachment structure and a strap; 
         FIG. 49  is a perspective view that illustrates an embodiment of an attachment structure being attached to a wheeled platform apparatus; 
         FIG. 50  is a exploded view that illustrates an embodiment of an attachment structure showing placement of axle and tensioner; and 
         FIG. 51  is a side view that illustrates an embodiment of a wheeled platform apparatus with a non-rolling portion of a heeling apparatus positioned in contact with the surface as a brake. 
     
    
    
     DETAILED DESCRIPTION 
     It should be understood at the outset that although an exemplary implementation of the present invention is illustrated below, the present invention may be implemented using any number of techniques, materials, designs, and configurations whether currently known or in existence. The present invention should in no way be limited to the exemplary implementations, drawings, and techniques illustrated below, including the exemplary designs and implementations illustrated and described herein. 
       FIGS. 1-21  and the accompanying description illustrate and describe various aspects of a heeling apparatus and method as exemplary athletic footwear that may be configured, modified or employed to cooperate with a wheeled platform apparatus  1000 , according to one or more aspects of the present invention. It should be appreciated, however, that the present invention is not limited to the construction, configuration and implementations of the heeling apparatus illustrated in  FIGS. 1-21  and may be utilized on any footwear, skates or with additional or different components or configurations that are within the scope of the present invention. 
       FIG. 1  is a side view of a heeling apparatus  10  implemented using an athletic shoe  12  according to one embodiment of the present invention. The heeling apparatus  10  preferably includes a wheel assembly provided in an opening in the heel portion of the sole of a footwear. For example the athletic shoe  12  includes an opening in the bottom of a heel portion  18  of a sole  14  with a wheel assembly provided in the hole such that a wheel  16  extends below the bottom of the sole  14 . The wheel assembly preferably includes at least one wheel, such as the wheel  16 , rotatably mounted on an axle (not illustrated in  FIG. 1 ). The wheel  16  mounted on the axle is preferably positioned in the opening of the sole  14  through a mounting structure (not illustrated in  FIG. 1 ) that is operable to support the axle such that a portion of the wheel  16  extends below the heel portion  18  of the sole  14 . 
     The amount or length of the portion of the wheel  16  that extends below the bottom of the sole  14 , as defined by a distance  24 , will preferably be less than the diameter of the wheel  16 . The distance  24 , however, may be greater than, less than, or equal to the diameter of the wheel  16 . 
     The athletic shoe  12 , as is true of most footwear, may be generally described as having the sole  14  and an upper part  26 . The upper part  26  may be constructed of virtually any material such as, for example, leather, plastic, or canvas. The sole  14  may include three parts: (1) an inner sole or insole (not illustrated in  FIG. 1 ); (2) a midsole  28 ; and (3) an outer sole or outsole  30 . The insole may provide added cushion and may or may not be removable. In some embodiments, the insole may include a removable portion, such as a DR. SCHOLL&#39;S insole, and a portion that remains attached to the athletic shoe  12 . The outsole  30  will preferably be made of a durable material, such as rubber, and may have a textured surface, such as with knobbies, to provide added traction. The midsole  28  will generally be constructed of a soft or “cushiony” material and will generally be thicker than the insole and the outsole  30 . In some embodiments, however, the sole  14  will comprise only one part, such as the leather sole of a loafer. In other embodiments, the sole  14  may include a separate heel block or object that elevates the footwear, such as the heel of a leather wingtip dress shoe. This heel block or object may be considered to be part of the heel portion  18  of the sole  14 . It should be understood that the present invention may be implemented in virtually any footwear, irrespective of the design or the make-up of the sole  14 . Various styles of footwear and methods of making footwear are known in the art and are known by one of ordinary skill in the art. For example, U.S. Pat. Nos. 4,245,406, 5,319,869, 5,384,973, 5,396,675, 5,572,804, 5,595,004, and 5,885,500, which are hereby incorporated by reference for all purposes, provide various background information regarding various footwear and methods of making footwear. 
     In most footwear, including the athletic shoe  12 , the sole  14  may also be divided into three portions or regions: (1) the heel portion  18 , (2) an arch portion  20 , and (3) a forefoot portion  22 , as illustrated in  FIG. 1 . It should be understood that the heel portion  18 , the arch portion  20 , and the forefoot portion  22  of the sole  14  are incapable of being exactly defined and located, and that such portions vary from one footwear type to another. Thus, the location, the boundaries between, and the size of the heel portion  18 , the arch portion  20 , and the forefoot portion  22  of the sole  14  are only rough approximations. 
     It should also be understood that although the position of the opening in the bottom of the sole  14 , and hence also the wheel  16 , is preferably located in the heel portion  18  of the sole  14 , such an opening may also be located at the boundary of the heel portion  18  and the arch portion  20 , at the arch portion  20 , or at virtually any other location on the sole  14 . The opening in the bottom of the sole  14  may extend entirely through the sole  14 , e.g., through the outsole, the midsole and the insole, or only partially through the sole  14 , e.g., through the outsole, and a portion or all of the midsole. 
     The wheel  16  may be constructed or made of virtually any known or available material such as, for example, a urethane, a plastic, a polymer, a metal, an alloy, a wood, a rubber, a composite material, and the like. This may include, for example, aluminum, titanium, steel, and a resin. Preferably, the material will be durable, provide quiet performance, and will provide a “soft” or “cushioning” feel. In one embodiment, the wheel  16  may be implemented as one or more precision bearings such that the precision bearing serves as the wheel  16  itself. In yet another embodiment, the wheel assembly may include a spring or suspension such as, for example, a leaf spring, to provide additional cushion or suspension when the wheel  16  contacts a surface and a force is applied to the athletic shoe  12  in the direction of the surface, such as when a someone is wearing and walking in the heeling apparatus  10 . The spring is preferably provided as part of the mounting structure of the wheel assembly. In still another embodiment, the wheel  16  is provided as a two piece wheel with an inner core, such as a hard inner core, such as a hard inner core, surrounded by an outer tire, such as a urethane tire. 
     Depending on the desired implementation, the wheel  16  and the axle may be removable from the wheel assembly. In such a case, a removable cover may be provided in the opening in the sole  14  to cover the opening so that debris and dirt does not enter the opening. The removable cover may be provided in virtually any available configuration readily ascertainable by one of ordinary skill in the art. In one embodiment of the removable cover, an axle portion of the removable cover fits and/or couples to the mounting structure in the same or similar manner that the axle in which the wheel  16  is mounted fits and/or couples to the mounting structure of the wheel assembly. A tool may also be provided to facilitate the removal of the axle and wheel  16 . This tool will, preferably, be small and multi-functional to provide any other possible adjustments to the heeling apparatus  10 , such as a screw driver, a wrench, and the like. In other embodiments of the heeling apparatus  10 , the wheel  16  may be retractable into the opening in the sole  14 . In this manner, the wheel  16  may be retracted into the sole  14  and, thus, will not extend below the bottom of the sole  14 . This allows the heeling apparatus  10  to function just like ordinary footwear, such as the athletic shoe  12 . 
     In one embodiment of the present invention, the wheel assembly does not include an axle, and, arguably, not a mounting structure, and the wheel  16  is provided as a sphere, such as a stainless steel ball bearing, that is rotatably positioned in the opening in the bottom of the heel portion  18  of the sole  14 , one embodiment of which is shown in  FIG. 13 . In another embodiment, the wheel assembly comprises an axle positioned completely through or partially through the heel portion  18  of the sole  14  such that the sole  14  supports the axle and the wheel is rotatably mounted on the axle in the opening of the sole  14 . In this manner, the need for the mounting structure is eliminated. 
     In operation, a person wearing the heeling apparatus  10  may either walk normally or roll on the wheel  16  by lifting or raising the sole  14  so that only or almost only the wheel  16  contacts a surface. This action may be referred to as “HEELING” or to “HEEL.” The wheel  16 , depending on the desired implementation of the present invention, may be removed or retracted to a position such that the wheel  16  does not extend below the bottom of the sole  14 . This, generally, will result in the heeling apparatus  10  performing like an associated footwear. When the wheel  16  is removed or retracted, a removable cover may be placed over the opening in the bottom of the sole  14  to prevent debris from entering the opening and potentially damaging the wheel assembly. In still other embodiments, a removable cover may be placed over the wheel  16  while a portion of the wheel  16  remains extended below the bottom of the sole  14  to assist with walking, an example of this is illustrated in  FIG. 12 . 
     It should be understood, however, that even if the wheel  16  is not removed or retracted as just described, the user may still comfortably walk and run, even with the wheel  16  extended. This generally occurs because the distance  24  can be minimal, which provides a unique “stealth” or “covert” aspect to heeling. This also results in the wheel rolling the opening or hole in the sole  14  of the heeling apparatus  10 . In one embodiment, the distance  24  is less than the radius of the wheel  16 , which results in most of the wheel residing within the opening of the sole  14 . 
       FIGS. 2A and 2B  are bottom views of two embodiments of the sole  14  of the heeling apparatus  10 . In particular, the outsole  30  or bottom of the sole  14  is illustrated in  FIG. 2A  with an opening  40  in the heel portion  18  of the sole  14 . In the embodiment illustrated, the opening  40  is provided in a square or rectangular configuration. The opening  40 , however, may be provided in virtually any configuration, such as, for example, a circular or an elliptical configuration. 
     As mentioned previously, the opening  40  may extend partially or completely through the sole  14 . The opening  40  may be provided through a heel block or object. Further, the opening  40  be positioned in, near, or in a combination of the heel portion  18 , the arch portion  20 , and the forefoot portion  22 . 
       FIG. 2B  illustrates a second embodiment as to the placement and configuration of the opening  40 . The outsole  30  is illustrated with an opening  40 A and an opening  40 B in the heel portion  18  of the sole  14 . In this manner, one or more wheels, including one or more axles, may be positioned in both the opening  40 A and  40 B. 
       FIGS. 3A and 3B  are bottom views of the two embodiments of the sole  14  as shown in  FIGS. 2A and 2B  and illustrate a wheel in each of the openings of the soles. This includes a wheel  42  positioned in the opening  40  in  FIG. 3A  and a wheel  42 A and a wheel  42 B in the openings  40 A and  40 B, respectively, of  FIG. 3B . 
     The wheel  42  and the wheels  42 A and  42 B are illustrated as cylindrical wheels. These wheels, however, may be provided in virtually any available configuration. Further, one or more wheels may be positioned in each opening. 
       FIG. 3A  further illustrates other elements of the wheel assembly that include a first member  48  and a second member  54  of a mounting structure that is used to removably couple with an axle  50 . The axle  50  extends through the wheel  42  such that the wheel  42  is rotatably coupled or mounted to the axle  50 . This preferably involves the use of precision bearings, such as high performance precision bearings, provided in a recess, such as an annular recess, on either side of the wheel  42 . A first precision bearing  56  and a second precision bearing  58  may be ABEC grade precision bearings and are illustrated with hidden lines and positioned in the first recess and second recess of the wheel  42 . In alternative embodiment, loose ball bearings may be used. 
     The axle  50  may be made of any material that provides suitable physical characteristics, such as strength and weight, to name a few. The axle  50  is preferably made of hardened steel, is cylindrical in shape, each end is rounded, and is removably coupled with a first member  48  and a second member  54 , respectively, of the mounting structure. The removable coupling between each end of the axle  50  and the first member  48  and the second member  54  may be achieved by any known or available mechanism. In a preferred embodiment, a sphere or a ball bearing, preferably using a moveable spring and/or a screw bias, is used to contact and exert a side wall force between one or members of the mounting structure and the axle  50 . 
     It should also be noted that because the weight of the user of the heeling apparatus  10  will exert a significant downward force and the ground or surface will exert an equal force upward, the axle  50 , and, hence, the wheel  42  will generally be forced into place. Only when the heel is raised from a surface will any force or friction be required to keep the axle  50  in place. Thus, the present invention does not require a large side force to keep the axle  50  and the wheel  42  in place. The recognition of this fact may be considered an aspect of the present invention for the embodiment as shown. This recognition allows the removable coupling between each end of the axle  50  and the first member  48  and the second member  54  to be optimally designed. 
       FIG. 3A  also illustrates a grind plate  44  (which also may be referred to as a slide plate  44 ) that may be used in conjunction with the heeling apparatus  10  of the present invention. The grind plate  44  provides a smooth or relatively smooth surface to allow a user to “grind” or “slide” on various surfaces such as hand rails, curbs, steps, corners, and the like. The grind plate  44  is preferably somewhat thin and made of a plastic or polymer material. In a preferred embodiment, the grind plate  44  is removably attached to the arch portion  20  of the outsole  30  of the sole  14 . The grind plate  44  may be attached using any known or available fastener, such as, for example, a fastener  46  shown in various locations around the periphery of the grind plate  44 . 
       FIG. 3B  further illustrates an axle  52  in which the wheel  42 A and the wheel  42 B are coupled to either end in the opening  40 A and the opening  40 B, respectively. The axle  52  extends through both the wheels  42 A and  42 B and through a portion of sole  14 , not visible in  FIG. 3B . This serves to support the axle  52  and illustrates the situation where the sole  14  serves as the mounting structure of the wheel assembly. This reduces the overall number of parts. In an alternative embodiment, a metal or some other suitable material may be used within the heel portion  18  of the sole  14  where the axle  52  is positioned to provide additional support and stability. This is an example where the mounting structure is, in effect, integrated into the sole  14 . As can be appreciated by one skilled in the art, the present invention may be implemented in any number of ways. 
       FIG. 4  is a perspective view of a wheel  60  rotatably mounted on an axle  62 , which also may be referred to as a wheel/axle assembly, for use in a wheel assembly, or in a heeling apparatus, according to one embodiment of the present invention. The wheel  60  and the axle  62  may also be referred to as a wheel/axle assembly  400 . In this embodiment, the axle  62  extends through the wheel  60  and includes two ends that are rounded or bullet shaped. A precision bearing  64  is shown positioned in a recess, which is shown as an annular recess, of the wheel  60  to facilitate the rotation of the wheel  60  around the axle  62 . Preferably a second precision bearing is positioned in a second recess, not shown in  FIG. 4 , to further facilitate such rotation. 
     A slip clip, slip ring, or ring clip  66  is shown positioned around, or nearly around, the axle  62  near the precision bearing  64 . This serves to ensure that the precision bearing  64  remains in place in the recess of the wheel  60 . The slip clip or ring clip  66  will preferably be positioned on the axle  62  through a groove, such as a radial groove or radial indentation, in the axle  62 . It should be understood, however, that one of ordinary skill in the art may use any of a variety of other arrangements to ensure that the precision bearing  64  stays in position. In alternative embodiments, the precision bearing  64  may be eliminated or loose bearings may be used. 
     The wheel  60  rotatably mounted on the axle  62  may, in alternative embodiments, serve as the wheel assembly of the present invention. In such a case, the axle  62  may be mounted to the sole, such as the midsole and heel portion, at its ends while the wheel  60  is rotatably provided in the opening of the sole. In this manner, the need for a mounting structure may be thought of as eliminated or, alternatively, the mounting structure may be thought of as integrated into the sole of the footwear. 
       FIG. 5  is a perspective view of a mounting structure  70  for use with a wheel rotatably mounted to an axle, such as is illustrated in  FIG. 4 , to form a wheel assembly. The mounting structure  70  generally includes a heel control plate  72 , a first member  74 , and a second member  76 . In alternative embodiments, a spring, such as a leaf spring, could be provided where the two members contact the heel control plate  72 . This would provide the added benefit of greater cushion and suspension. The two members include an opening, such as the opening  78  of the first member  74  to receive an end of an axle. It should be mentioned that the opening may be provided in virtually any configuration, including extending through the member, or placed at different positions, or even multiple positions for mounting the wheel/axle assembly  400  at a retractable position and an extended position, on the member. 
     The axle that is to be positioned in the openings of the first member  74  and the second member  76  will preferably be removably coupled. This may be achieved by any number of arrangements and configurations, all of which fall within the scope of the present invention. One such arrangement is the screw/spring/ball bearing arrangement  80  provided in first member  74 . This arrangement provides an adjustable bias or force that can be exerted against the axle when it is inserted into the opening  78 . The screw is accessible and adjustable by the user. The turning of the screw affects the compression of a spring which, in turn, provides a force on a ball bearing that extends out into the opening  78 . When the axle is inserted into the opening  78 , the ball bearing may be displaced an amount and the screw/spring/ball bearing arrangement  80  will provide a side force to allow the axle to be secure, yet removable. A similar arrangement may also be provided in the second member  76  to provide a friction fit or coupling on the other end of the axle  62 . 
     Although the screw/spring/ball bearing arrangement  80  of  FIG. 5  is shown being implemented through a horizontal opening in the first member  74 , it may be implemented in using an opening aligned in virtually in manner in the member. For example, the adjustment of the tension or pressure on the screw/spring/ball arrangement  80  may be achieved through a diagonal opening such that the exposed end of the screw/spring/ball arrangement  80 , normally a screw head end, is provided where the reference line for numeral  74  in  FIG. 5  contacts the first member  74 . This provides easier access to adjust the tension and friction fit on the axle  62  when the wheel assembly, such as wheel assembly  100  of  FIG. 6 , is engaged or positioned within the opening of a sole to form a heeling apparatus. Of course, any of a variety of other arrangements, configurations, and opening alignments may be contemplated and implemented under the present invention. 
     The mounting structure  70  can be made or constructed of virtually any material, generally depending on the desired mechanical characteristics such as, for example, rigidity and strength. These materials may include, for example, a plastic, a polymer, a metal, an alloy, a wood, a rubber, a composite material, and the like. This may include aluminum, titanium, steel, and a resin. In one embodiment, the mounting structure  70  is made of a metal, such as aluminum, that has been anodized such that the mounting structure  70  presents a black color or hue. 
       FIG. 6  is a bottom view of a wheel assembly  100  that includes the wheel  60  rotatably mounted to the axle  62 , as shown in  FIG. 4 , and the mounting structure  70  of  FIG. 5 . The first member  74  and the second member  76  each removably couple with the ends of the axle  62  through a bias mechanism implemented using a bias mechanism, such as the screw/spring/ball bearing arrangement  80 . A ball bearing  102  is shown contacting one end of the axle  62  in the opening  78 . Further slip clips or ring clips (which may also be referred to as snap rings or slip rings), such as ring clip  66 , are provided to ensure that the precision bearings positioned in the recesses of the wheel remain in position. 
     The heel control plate  72  allows the user of the heeling apparatus to gain greater control and to obtain greater performance out of the heeling apparatus. 
       FIG. 7  is a side view of the wheel assembly  100  positioned above and through the opening to form a heeling apparatus  120 . The heel control plate  72  resides inside the shoe so that the heel of the user may apply pressure to the heel control plate as desired to provide better handling and performance of the heeling apparatus  120 . 
       FIGS. 8A ,  8 B,  8 C, and  8 D are profile views of various wheels  200  that illustrates the surface profile of these wheels that may used in various embodiments of the present invention. In  FIG. 8A , a wheel  202  is shown with a flat or square surface or exterior profile  204 . In  FIG. 8B , a wheel  206  is shown with an inverted surface profile  208 . In  FIG. 8   c , a wheel  210  is shown with round surface profile  212 . Finally, in  FIG. 8D , a wheel  214  is shown with a steep surface profile  216 . The present invention may incorporate virtually any available surface profile of a wheel. 
       FIG. 9  is a perspective view that illustrates a mounting structure  500  of another embodiment for use in a wheel assembly of a heeling apparatus. The mounting structure  500  includes an axle  502 , which may be considered one axle that extends through and is mounted through a member  50  or as an axle  502  that couples with the member  506  along with an axle  504  that couples with the member  506  opposite axle  502 . The mounting structure  500  also includes a heel control plate  508  coupled with the member  506 . 
     The mounting structure  500  allows for two wheels to be mounted to form a wheel assembly. A wheel may be rotatably mounted on the axle  502 , preferably using a precision bearing, and a wheel may be rotatably mounted on the axle  504 , also preferably through a precision bearing as illustrated previously herein. 
     The axle  502  and the axle  504  include a threaded portion such that a nut, such as a lock nut  510  may be included to secure a wheel to each axle. In other embodiments, the end of the axles may include internal threads, as opposed to external threads as shown, so that a screw, such as the hex screw as shown in  FIG. 10 . It should be understood that virtually any available coupling may be provided between the axle and the member. 
       FIG. 10  is a perspective view that illustrates a wheel assembly  520  that uses yet another embodiment for use in a heeling apparatus and includes a wheel  522  rotatably mounted to an axle  524  using a precision bearing  526 , and a first member  528  and a second member  530  coupled to each end of the axle  524  through a screw, such as hex screw  532 . The wheel assembly  520  is similar to wheel assembly  100 , which was described above in connection with  FIG. 6 , except that the wheel/axle assembly cannot be as easily inserted and removed. 
       FIG. 11  is a side, partial cutaway view that illustrates one embodiment of a heeling apparatus  600  that illustrates a wheel assembly  602  provided in a sole  604  and an opening  606  in the sole  602  that does not extend completely through the sole  602 . As such, the mounting structure  608  may be provided or integrated into the sole  602  and may not be readily or easily removed. A wheel  610  is also shown extending partially below the bottom of the sole  602 , which provides the advantage of stealth heeling. 
       FIG. 12  is a side view of another embodiment that illustrates a heeling apparatus  620  of the present invention with a removable wheel cover  622  positioned to cover a wheel  624  and an opening  626  in a sole  628 . The removable wheel cover  622  allows for the wheel to be provided in an extended position, i.e., below the bottom surface of the sole  628 , yet not engage a surface to roll. Although the heeling apparatus  620  of the present invention allows a user to walk and run, even with the wheel in an engaged position, the removable wheel cover  622  provides protection from dirt and debris and provides greater stability. 
     In an alternative embodiment, a wheel stop, not expressly shown in  FIG. 12 , may be provided, in lieu of or in conjunction with the removable wheel cover  622 , to stop the rotation of the wheel  624 . In one embodiment, the wheel stop is made of virtually any material, such as a sponge or flexible material, that can be wedged between the wheel  624  and the opening  626  to stop or prevent the rotation of the wheel  624  and to stay in place through friction. 
     In other embodiments of the wheel cover  622 , a wheel cover is provided when the wheel  624  has been removed from the heeling apparatus  620 . In a preferred embodiment, this wheel cover is generally flush with the remainder of the bottom of the sole  608 , and, hence, provides the function of a regular shoe when desired and protects the opening. This wheel cover may couple in any available manner, but preferably will couple to the wheel assembly in the same or similar manner that the wheel/axle assembly couples to the mounting structure. The removable wheel cover could clip or attach to the wheel assembly in many different ways. 
       FIG. 13  is a bottom view that illustrates another embodiment of a heeling apparatus  700  with a spherical ball  702  serving as a wheel and positioned in a mounting structure  704  in an opening in the heel portion of the sole  706 . 
       FIG. 14  is a perspective view that illustrates a “heeler”  800  using the present invention to “heel.” Heeling can be achieved using various techniques and, generally, requires a skill set of balance, positioning, flexibility, and coordination. 
     An illustrative method for using a heeling apparatus on a surface may include running on a surface by using a forefoot portion of a sole of the heeling apparatus to contact the surface, and then rolling on the surface with a wheel of the heeling apparatus extended below the bottom of the sole through an opening in the sole by using a wheel of the heeling apparatus to contact the surface. Before running on a surface, the method may include walking on the surface while wearing the heeling apparatus with a wheel of the heeling apparatus extended below the bottom of a sole portion of the heeling apparatus before running on the surface. Heeling may also be performed on a hill or a surface that includes a decline. 
     The method of heeling may also include engaging the wheel of the heeling apparatus to extend below the bottom of the sole portion of the heeling apparatus before walking on the surface. The method may also include walking on the surface while wearing the heeling apparatus before engaging the wheel of the heeling apparatus and with the wheel of the heeling apparatus retracted. Other variations on the method may include transitioning from rolling on the surface to either running, walking, or stopping on the surface by running on the surface through using the forefoot portion of the sole of the heeling apparatus to contact the surface just after rolling on the surface. 
     The preferred position while heeling is illustrated by the heeler  800  in  FIG. 14  where one heeling apparatus  802  is placed in front of the other heeling apparatus  804  while rolling on a surface. As can be seen from a back heel portion  806  of the heeling apparatus  804 , sometimes the clearance between the back heel portion  806  and the surface is small. As a result, in a preferred embodiment, the back heel portion  806  is made of a wear resistant material. 
     The method of heeling may also implement any number of techniques for slowing or stopping. For example, rolling may be slowed by contacting the forefoot portion of the sole of the heeling apparatus to contact the surface to create friction and to remove the wheel from the surface. Another example includes slowing by contacting a heel portion of the sole of the heeling apparatus to contact the surface. 
       FIG. 15  is a perspective view that illustrates a wheel  902  rotatably mounted to a collapsible axle  904 , which also may be referred to as a wheel/axle assembly  900 , similar to  FIG. 4 . The collapsible axle  904  may be implemented in any number of ways, such as an adjustable axle that is spring loaded, similar to what is shown in  FIG. 16 , or as a screw collapsible axle. This allows the wheel/axle assembly  900  to be more easily removable and/or retractable to a position where the wheel would not engage the ground if the wheel/axle assembly  900  where implemented in a heeling apparatus. 
       FIG. 16  is a cutaway view that illustrates a collapsible axle  904  of the wheel/axle assembly  900  of  FIG. 15  implemented as a spring loaded collapsible axle. As can be seen, the collapsible axle  904  may be adjusted or shortened by inwardly compressing both ends of the collapsible axle  904  to overcome the internal spring force. 
       FIG. 17  is a perspective view that illustrates another mounting structure  920  for use with the wheel/axle assembly  900  and the collapsible axle  904 , as illustrated in  FIG. 15  and  FIG. 16 , respectively, to form a wheel assembly. The collapsible axle  904  may couple to a first member  922  and a second member  924  at a first position  926  at the first member  922  and the second member  924  so that the wheel is in a retracted position. The collapsible axle  904  may also couple to the first member  922  and the second member  924  at a second position  928  so that the wheel is in an extended position. 
       FIG. 18  is a side, cutaway view that illustrates a wheel assembly  940  positioned through an opening in a sole  942  that illustrates one embodiment of an axle  944  that couples to a mounting structure  946  to provide a retractable wheel  948  using an assembly that may be referred to as a king pin arrangement or dual king pin arrangement. This allows the retractable wheel  948  to be adjusted up or down, as desired, and from a retractable position to an extended position. A king pin  950  (which may be implemented as a threaded screw or bolt) is shown threadingly engaged in a threaded opening in a member of the mounting structure  946 . As the king pin  950  is screwed further into the opening in the member, the axle  944  is further retracted. A king pin  950  will also be provided at the other member to raise the other side of the axle  944 . In other embodiments, such as the mounting structure  500  in  FIG. 9 , a single king pin could be provided through the single member to provide retractable wheels through the coupling of the members and the axle. 
     An example of a king pin type assembly is illustrated in U.S. Pat. No. 4,295,655, which is incorporated herein by reference for all purposes, issued to David L. Landay, et al., was filed on Jul. 18, 1979, was issued Oct. 20, 1981. This patent illustrates a king pin type assembly that could be implemented in an embodiment of the present invention. 
       FIG. 19  is a bottom view that illustrates the wheel assembly  940  of  FIG. 18  and further illustrates the dual king pin arrangement and the king pins  950  through the members of the mounting structure  946 . 
       FIG. 20  is a side view that illustrates one member of the mounting structure  946  and further illustrates the coupling of the axle  944  to the mounting structure  946  using the dual king pin arrangement similar to  FIG. 18 . As discussed above, this allows the axle  944 , and hence the attached wheel, to be transitioned to any of a desired levels, and from a retracted position to an extended position. 
     It should be understood that the axle may couple to a member of a mounting structure using any available technique and in virtually an unlimited number of ways. For example, an axle may couple to the first member and the second member of a mounting structure to move from a retracted position to an extended position through a spring arrangement. Similarly, an axle may couple to the first member and the second member of a mounting structure to move from a retracted position to an extended position through a hinged arrangement. 
     Many other examples are possible, for example U.S. Pat. No. 3,983,643, which is incorporated herein by reference for all purposes, issued to Walter Schreyer, et al., was filed on May 23, 1975, was issued Oct. 5, 1976 illustrates a retractable mechanism that may implemented in one embodiment of the present invention. U.S. Pat. No. 5,785,327, which is incorporated herein by reference for all purposes, issued to Raymond J. Gallant, was filed on Jun. 20, 1997, issued on Jul. 28, 1998 illustrates simultaneously retractable wheels. 
       FIG. 21  is a breakaway and perspective view that illustrates a two piece wheel  970  that includes an inner core  972 , an outer tire  974 , such as a urethane wheel, an axle  976  (which may not be shown to skill), and a bearing  978  that may be used in the present invention. In a preferred embodiment, the bearing  978  is small in comparison to the two piece wheel  970 , for example, the bearing  978  may have an outer diameter that is less than half the outer diameter of the outer tire  974 . This can provide significant advantages, that include a softer ride, better control, and are longer lasting. This is because the outer tire  974  can be larger and thicker. In other embodiments, the bearing  978  is larger and has an outer diameter that is more than half the outer diameter of the outer tire  974 . In a preferred embodiment, the inner core portion of the two piece wheel is made of a harder material that provides rigidity for enhanced bearing support, while the outer tire portion is made of a softer material, such as a soft urethane, for improved performance and a quieter ride. These types of wheels may be referred to as a “dual durometer” type wheel. 
       FIG. 22A  illustrates a side isometric view of a wheeled platform apparatus  1000  according to one embodiment. The wheeled platform apparatus  1000  preferably includes a platform  1010 , which operates as a chassis, having a rear portion  1020 , a center portion  1030 , a front portion  1040 , a top surface  1050 , and a bottom surface  1060 . In some embodiments, the platform may also include a deckplate  1012 , which in some embodiments, as illustrated in  FIGS. 38 and 41D , may be interchangeably referred to herein as deckplate  1510 . The front portion  1040  of the bottom surface  1060  further includes a first or front wheel  1070  interfacing with the bottom surface  1060  and a second or rear wheel  1080  interfacing with the bottom surface  1060  of the platform  1010  to facilitate rolling movement of the wheeled platform apparatus  1000 . In some embodiments, the first wheel  1070  and/or the second wheel  1080  may be housed at least partially within the platform  1010 , with at least a portion of the first wheel  1070  and/or the second wheel  1080  extending at least partially below the bottom surface  1060  of the platform  1010  for contact with a surface, such as concrete, asphalt, or other suitable surface, upon which the wheeled platform apparatus  1000  may roll. In still other embodiments, by housing the first wheel  1070  and/or the second wheel  1080  at least partially within the platform  1010 , the platform  1010  may be positioned closer to the ground, which lowers the center of gravity of the wheeled platform apparatus  1000 , and enhances the stability and safety of the wheeled platform apparatus. 
     In some embodiments, the platform  1010  may be made of metal, wood, biofiber, plastic, polymer, ceramic, composite, acrylic, renewable, recycled, or other suitable materials capable for supporting a user&#39;s weight as intended or desired. 
     Referring again to  FIG. 22A , in some embodiments, the first wheel  1070  and the second wheel  1080  may be positioned at least partially along a longitudinal centerline of the platform  1010  that extends from the rear portion  1020  to the front portion  1040  along the center of the platform  1010 , as further illustrated, for example, by  FIGS. 22B and 23 , with the first wheel  1070  being positioned in the front portion  1040  of the platform  1010  and the second wheel  1080  being positioned in the rear portion  1020  of the platform  1010 . The general direction of the longitudinal centerline is further illustrated generally by  FIGS. 28 ,  29 A,  29 E, and  41 F, which show a heeling apparatus  2000  being positioned with its heel and toe primarily along the longitudinal centerline of the of the platform  1010 , which is generally in the rolling direction of the platform. In other embodiments, either the first wheel  1070  or the second wheel  1080  may be positioned partially or fully in the center portion  1030  of the platform  1010 . Additionally, in other embodiments, the first wheel  1070  and the second wheel  1080  may be positioned offset from the longitudinal centerline of the platform  1010  (i.e., the first wheel  1070  and the second wheel  1080  may be positioned to interface with the bottom surface  1060  of the platform  1010  at any location along the bottom surface  1060 ). 
     In other embodiments, the wheels may be positioned or configured in virtually any known or desired position, including side-by-side, inline. For example, when the first wheel  1070  and the second wheel  1080  are positioned adjacent to the bottom surface  1060  of the platform  1010  in a manner such that both wheels reside below the area of contact between the wheeled platform apparatus  1000  and the user&#39;s foot, the user&#39;s safety and control of the wheeled platform apparatus  1000  is enhanced based at least partially upon the user&#39;s ability to steer the wheeled platform apparatus  1000  with one foot. Further, it should be understood that the wheeled platform apparatus  1000  may include wheels in addition to the first wheel  1070  and the second wheel  1080 . 
     In other embodiments the first wheel  1070  and/or the second wheel  1080  may be permanently attached, removable, or retractable to the platform  1010 . 
     Referring to  FIG. 47 , in other embodiments, the first wheel  1070  and/or the second wheel  1080  may be attached to the wheeled platform apparatus  1000  by a friction fit, snap fit, or other suitable fit, including those as described herein and illustrated above in  FIGS. 5 ,  6 ,  9 ,  10 ,  17 ,  18 , and  19 . 
     In other embodiments, the first wheel  1070  and/or the second wheel  1080  may be a wheel attached to a swivel capable of orienting in a full 360 degree spectrum on a vertical axis for directional rolling, also known as a caster wheel. Other types of wheels capable of orienting along at least a portion of a 360 degree spectrum may also be used, such as a ball bearing or spherical trackball. 
     In yet other embodiments, the first wheel  1070  and/or second wheel  1080  may be illuminated, via one or more LEDs or other illuminating device, by battery power, induction power, or other suitable means for powering an illumination device. 
     Referring generally to  FIGS. 22A ,  23 ,  24 ,  25 ,  26 ,  27 ,  29 A,  29 B,  29 C,  29 D,  31 ,  32 ,  33 ,  34 ,  35 ,  36 A,  36 B,  37 , and  48  an attachment structure  1090 , which may be interchangeably referred to herein as attachment structure  1514  (as illustrated, for example, in  FIG. 38 ), interfacing with or positioned adjacent to the top surface  1050  of the platform  1010  is provided for mating, via snap fit, friction fit, magnetic fit, or other suitable mating means, with a non-wheeled or wheeled footwear, including a heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , external wheel assembly  2008 , or other wheeled skate, or a user&#39;s bare foot. In some embodiments, the heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , and/or external wheel assembly  2008  may have removable or permanent wheel assemblies that snap fit, friction fit, strap-on, or are otherwise fastened onto a user&#39;s foot or footwear. Referring again to  FIG. 29D , the external wheel assembly  2008  may consist of a frame having one or more wheels attached thereto with at least a portion of a wheel extending below the bottom of the footwear for contacting with a surface for rolling. In some embodiments, the frame of the external wheel assembly  2008  is removably mounted onto the user&#39;s foot or footwear using one or more straps, friction fit, snap fit, or other suitable mating means. 
     Referring again to  FIG. 48 , in some embodiments, use of an attachment structure  1090  provides a secure connection with a non-wheeled or wheeled footwear, such as a heeling apparatus  2000 , thereby enhancing control of the wheeled platform apparatus  1000  by the user as yaw movements between the user&#39;s foot and the wheeled platform apparatus  1000  or separation of the user&#39;s foot from the wheeled platform apparatus  1000 , which are common in other wheeled platforms, such as skateboards, are eliminated or substantially reduced, thereby increasing controllability, steering, performance (e.g., tricks or stunts), and safety. 
     In still other embodiments, the attachment structure  1090  securely attaches only to a heel portion of a heeling apparatus  2000 , thereby eliminating the need to buckle, bind, or otherwise adjust cumbersome secondary binding attachments, such as forefoot straps. In some embodiments, the attachment structure  1090  projects from the top surface  1050  of the platform  1010  for mating with a recessed heel opening and/or wheel mounting structure within the heel of a heeling apparatus  2000 , said heel opening and/or wheel mounting structure may be implemented as that generally described above and/or illustrated in  FIGS. 2A ,  2 B,  3 A,  3 B,  5 ,  6 ,  9 , and  10 . 
     In some embodiments, the attachment structure  1090  is preferably positioned in the rear portion  1020  of the top surface  1050  of the platform  1010  along the longitudinal centerline of the platform  1010 . However, in other embodiments, the attachment structure  1090  may be positioned anywhere upon the platform that allows for mating with a non-wheeled or wheeled footwear, including a heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , external wheel assembly  2008 , or other wheeled skate, or a user&#39;s bare foot. In other embodiments, as illustrated in  FIG. 44 , the attachment structure  1090  may be positioned adjacent to or partially within the top surface  1050  of the wheeled platform apparatus  1000  in a manner operable to allow for mating with a non-wheeled or wheeled footwear, including a heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , external wheel assembly  2008 , or other wheeled skate, or a user&#39;s bare foot primarily along the longitudinal centerline of the platform  1010 , which in some embodiments may be at an angle offset from the rolling direction or longitudinal centerline of the platform  1010  of the wheeled platform apparatus  1000 . For example positioning the user&#39;s non-wheeled or wheeled footwear or bare foot primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 15 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . In other embodiments, for example, positioning the user&#39;s non-wheeled or wheeled footwear or bare foot primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 45 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . Other angles are possible and are a matter of the user&#39;s preference. 
     Referring to  FIG. 45 , in other embodiments, the attachment structure  1090 , which projects from the platform  1010 , may be received by a heel opening and/or wheel mounting structure, being generally described above and illustrated in  FIGS. 2A ,  2 B,  3 A,  3 B,  5 ,  6 ,  9 , and  10 , of a heeling apparatus  2000  and removably attach to the heeling apparatus  2000  by friction fit, snap-fit, magnetic fit, or other suitable mating means, including, for example, a curved projection  1092  for interfacing with an axle recess extending into a heeling apparatus  2000 . 
     Referring to  FIGS. 31 and 45 , in some embodiments, the attachment structure  1090  may be adjustable to mate with heeling apparatuses  2000  of various embodiments and sizes, some of which may include heel openings and/or mounting structures of different dimensions and structure. For example, an attachment structure  1090  may have a curved projection  1092  for interfacing with a wheel opening or axle recess extending into the bottom surface opening in the heel of a heeling apparatus  2000 , wherein the curved projection  1092  is capable of widening or lengthening, under a bias from a spring or through some other suitable mechanism, inward into the attachment structure  1090 , thereby changing the axial length or width of the curved projection  1092  for mating with openings, such as heel openings, of certain embodiments of the heeling apparatus  2000 . 
     Referring again to  FIGS. 31 and 45 , in some embodiments, the attachment structure  1090  projects from the rear portion  1020  of the top surface  1050  of the platform  1010  along the longitudinal centerline of the platform  1010  and is formed to interface or couple, by hook, friction fit, magnetic, or other suitable means, with an axle structure  1130  that is attached to a heeling apparatus  2000 . The axle structure  1130  may be a solid bar or a longitudinally biased bar capable of adjusting its length, by a spring or other suitable means, so that its overall length may be adjusted, thereby allowing the axle structure  1130  to interface with variable sized heel openings, which, as described above, cooperate with variable sized wheel and axle assemblies, of various embodiments of the heeling apparatus  2000 , including heeling apparatuses of different sizes. 
     Referring to  FIGS. 32 and 33 , in yet other embodiments, the attachment structure  1090  may comprise a first clamp arm  1330  and a second clamp arm  1340  mating with a recess in the first side portion  1322  and the second side portion  1324  of the wheel  1320 , or other projection, extending from a heeling apparatus  2000  or other footwear, including an inline skate or quad wheeled skate. 
     Referring again to  FIG. 33 , in yet other embodiments, the attachment structure  1090  may comprise a recess  1310 , which may extend into the platform  1010 , for mating with a wheel  1320 , or other projection, extending from a heeling apparatus  2000  or other footwear, including an inline skate or quad wheeled skate. 
     In still other embodiments, attachment of the wheeled platform apparatus  1000  to a heeling apparatus  2000  or other type of wheeled footwear or skate having a wheel may be by one or more projections extending from the attachment structure  1090  or directly from the wheeled platform apparatus  1000 , wherein the one or more projections mate by friction to at least a portion of the wheel. In some embodiments, the mating projection may be a “c” shaped curve projection that encircles at least a portion of the wheel and mates by friction fit. In yet other embodiments, one or more mating projections may be used to create a friction fit between a portion of the wheel and the recess of a heeling apparatus  2000 . 
     Referring again to  FIG. 48 , in still other embodiments, attachment of the wheeled platform apparatus  1000  to a heeling apparatus  2000  or other form of skate or footwear, including an inline skate, other wheeled skate, or non-wheeled footwear, may include, as the attachment structure  1090 , a lever or force operated binding system as used in snow skis, snowboards, locking bicycle pedals, and the like. Such a system can include bindings capable of fitting around the outer heel section of the non-wheeled or wheeled footwear, including a heeling apparatus  2000 , inline skate, or other wheeled skate. Other embodiments for attaching non-wheeled or wheeled footwear, including a heeling apparatus  2000 , inline skate, or other wheeled skate, or a user&#39;s bare foot to a wheeled platform apparatus  1000  include straps for securing the non-wheeled or wheeled footwear or a user&#39;s foot to the wheeled platform apparatus  1000 . 
     The attachment structure  1090  may be made of plastic, polymer, composite, ceramic, metal, or other suitable materials. 
       FIG. 22B  illustrates one embodiment of the wheeled platform apparatus  1000  that does not include an attachment structure  1090 . 
       FIGS. 34 ,  35 ,  36 A,  36 B, and  37  illustrate one embodiment of the wheeled platform apparatus  1000 , wherein the platform  1010  has a deckplate  1012 , which in some embodiments, as illustrated in  FIGS. 38 and 41D , may be interchangeably referred to herein as deckplate  1510 , positioned adjacent to the top surface  1050  of the platform  1010 . In some embodiments, the deckplate  1012  may be removably attached to the platform  1010 . In still other embodiments, the deckplate  1012  may be permanently attached to the platform  1010 . 
     Referring again to  FIGS. 34 and 35 , in other embodiments, the deckplate  1012  may be removably attached to the platform  1010  by fastening the attachment structure  1090  to the platform  1010  with the deckplate  1012  positioned therebetween. In yet other embodiments, the attachment structure  1090  has a projection  1094  that may interfit with a deckplate cutout  1013  for enhancing the attachment of the deckplate  1012  to the platform  1010  by limiting yaw and other side-to-side movements of the deckplate  1012  relative to the platform  1010 . 
     Referring to  FIGS. 46A and 46B , in yet other embodiments, the platform  1010  may have a lip or other projection for sliding, snapping, or otherwise placing a portion of the deckplate  1012 , such as its edge, between the lip or other projection and the platform  1010 , thereby securing the deckplate  1012  to the platform  1010 . In some embodiments, removal of the deckplate  1010  from the wheeled platform apparatus  1000  may occur by lifting the back of the deckplate  1010  and pulling the deckplate back and away from the lip or other projection for sliding, snapping, or otherwise placing a portion of the deckplate  1012 , such as its edge, between the lip or other projection and the platform  1010 . 
     Referring again to  FIGS. 36A and 36B , in still further embodiments, a removable deckplate locking structure  1014  may be used to provide a point of attachment, which may be used alone or in combination with the attachment structure  1090  as illustrated in  FIGS. 34 and 35 , for attaching the deckplate  1012  to the platform  1010 . The removable deckplate locking structure  1014  may be screwed, bolted, snap fitted, or fastened by other suitable mechanisms to the platform  1010  with the deckplate  1012  positioned and secured therebetween or secured by a lip or other projection extending outwardly from the deckplate locking structure  1014  for interfacing with the deckplate  1012 . In some embodiments, the deckplate locking structure  1014  may be positioned at the forefoot portion  1040  of the platform  1010 , but in still other embodiments, the deckplate locking structure  1014  may be positioned anywhere on the platform  1010 . In still other embodiments, the deckplate locking structure  1014  may be made of plastic, polymer, composite, ceramic, metal, or other suitable materials. 
     Referring again to  FIG. 37 , in still further embodiments, a removable deckplate fastener  1016  may be positioned adjacent to, and/or extend from, the underside of the deckplate  1012  for mating, via friction and/or snap fitting, with a platform recess  1018  in the platform  1010  to provide a mechanism of attachment, which may be used alone or in combination with the attachment structure  1090  and/or deckplate locking structure  1014  as illustrated in  FIGS. 34 ,  35 ,  36 A, and  36 B for attaching the deckplate  1012  to the platform  1010 . In still other embodiments, the deckplate fastener  1016  may be made of plastic, polymer, composite, ceramic, metal, or other suitable materials. 
     Referring again to  FIGS. 34 and 35 , in still further embodiments, the deckplate  1012  may be knurled or otherwise textured for enhancing grip with the user&#39;s foot or footwear, thereby enhancing control of the wheeled platform apparatus  1000  by the user. Such enhanced control contributes to increased usability by the user for directional steering, performing stunts, maneuvers, and tricks with wheeled platform apparatus  1000 , and further enhances safety. In still other embodiments, the deckplate  1012  may have graphics or colors for enhancing aesthetic appeal. 
     Referring again to  FIGS. 34 and 35 , in other embodiments, the deckplate  1012  may be made of or include a shock absorbing material, such as polymer, gel, rubber, or other substance, for providing shock absorption and/or suspension for the wheeled platform apparatus  1000  and the user. In yet other embodiments, the deckplate  1012  may include a shock absorbing material, such as gel, rubber, liquid, encapsulated pockets of gas, or other suitable substance, capable of absorbing mechanical forces, shock and/or providing suspension for the wheeled platform apparatus  1000  and the user. In still other embodiments, a shock absorbing material, such as gel, rubber, liquid, encapsulated pockets of gas, or other suitable substance, may be partially or fully embedded within the deckplate  1012 , or may be positioned adjacent to the deckplate  1012  for providing shock absorption and/or suspension for the wheeled platform apparatus  1000  and the user. In yet other embodiments, a shock absorbing material, such as gel, rubber, liquid, encapsulated pockets of gas, or other suitable substance, may be positioned above and adjacent to the deckplate  1012  for providing shock absorption and/or suspension for the wheeled platform apparatus  1000  and the user. In still other embodiments, a shock absorbing material, such as gel, rubber, liquid, encapsulated pockets of gas, or other suitable substance, and/or springs, foams, or other types of suitable shock absorbers and/or suspension may be positioned adjacent to the top surface  1050  of the platform  1010  and below and adjacent to the deckplate  1012  to provide shock absorption and/or suspension for the wheeled platform apparatus  1000  and the user. 
     Referring again to  FIGS. 34 and 35 , in other embodiments, the deckplate  1012  may be at least partially clear, at least partially translucent, or otherwise at least partially non-opaque to allow for aesthetic visibility through the deckplate  1012  for viewing, for example, a shock absorbing material, such as gel, rubber, liquid, encapsulated pockets of gas, or other suitable substance, and/or springs, foams, or other types of suitable shock absorbers and/or suspension. In yet other embodiments, the platform  1010  may house illumination devices, such as LEDs or lights, for illuminating the wheeled platform apparatus  1000 . The illumination devices may be powered by battery power, solar power, or other suitable power means. In yet other embodiments, the illumination devices may be powered by induction motors built into or in conjunction with the first or front wheel  1070  and/or the second or rear wheel  1080 . In still other embodiments, the illumination devices may project light through the deckplate  1012 , which may be at least partially clear, at least partially translucent, or otherwise at least partially non-opaque. Illumination of the wheeled platform apparatus  1000  by any method described herein or any other suitable method increases safety to the user by enhancing visibility of the wheeled platform apparatus  1000  and thus the user. 
     Referring again to  FIGS. 34 and 35 , in other embodiments, the deckplate  1012  may be made of plastic, polymer, composite, ceramic, metal, or other suitable materials. 
       FIGS. 22A ,  23 ,  29 A,  29 B,  29 C, and  29 D illustrate one embodiment of the wheeled platform apparatus  1000  having an arched grinding structure  1106  used for sliding or “grinding” along a surface while performing various techniques or tricks. The grinding structure  1106  is generally positioned along the bottom surface  1060  of the center portion  1030  of the platform  1010 , but may extend into the bottom surface  1060  of the rear portion  1020  and/or front portion  1040  of the platform  1010 . In some embodiments, the grinding structure  1106  may be permanently attached to or removable from the platform  1010 . In yet other embodiments, the grinding structure  1106  may be molded as a continuous and permanent portion of the platform  1010 . In still other embodiments, the grinding structure  1106  may be textured. In further embodiments, the grinding structure  1106  may be made of metal, plastic, polymer, ceramic, composite, or any other material suitable for “grinding.” In some embodiments, the grinding structure  1106  may be made of the same material as the platform. 
       FIGS. 22A ,  22 B,  23 ,  24 ,  25 ,  27 ,  29 A,  29 B,  29 C,  29 D,  29 E,  30 A,  30 B,  30 C,  30 D, and  31  illustrate one embodiment of the wheeled platform apparatus  1000  having a foot rest  1100  positioned adjacent to the rear portion  1020  of the platform  1010  for resting the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. By resting the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , upon the foot rest  1100 , the user is able to roll or heel in conjunction with the wheeled platform apparatus  1000  without having to constantly exert muscle force to raise the forefoot portion of the heeling apparatus  2000  or other skate or rolling apparatus. This allows a user to roll great distances with less effort, and allows rougher surfaces to be traversed. The foot rest  1100  may be considered part of or adjacent the rear portion  1020 , and for example, the foot rest  1100  may extend from behind the rear portion  1020 , may extend from a side of the rear portion  1020 , may be removable from the rear portion  1020 , or may be part of the rear portion  1020 . 
     Referring again to  FIGS. 22A ,  22 B,  23 ,  24 ,  25 ,  27 ,  29 A,  29 B,  29 C,  29 D,  29 E,  30 A,  30 B,  30 C,  30 D, and  31 , in some embodiments, the foot rest  1100  extends horizontally or downwardly from the rear portion  1020  of the platform  1010  at any desired angle, such as an angle less than 180 degrees from a plane passing through the platform  1010  of the wheeled platform apparatus  1000 . In yet other embodiments, the foot rest  1100  extends upward from the rear portion  1020  of the platform  1010  at an angle less than 180 degrees from a plane passing through the platform  1010  of the wheeled platform apparatus  1000 , such as a plane that is parallel to a flat, level surface in which the wheeled platform apparatus  1000  rolls upon. 
     In other embodiments, the foot rest  1100  may be used as a braking surface by shifting the user&#39;s weight on the platform  1010  to raise the front portion  1040  and first wheel  1070  of the platform  1010  thereby downwardly angling the rear portion  1020  of the platform  1010 , which brings the foot rest  1100  into contact with the surface upon which the wheeled platform apparatus is rolling (i.e., concrete, asphalt, etc.). This interface between the foot rest  1100  and the rolling surface creates friction, thereby slowing the rolling of the wheeled platform apparatus  1000 . 
     In some embodiments, the foot rest  1100  may be textured to enhance grip with the heeling apparatus  2000  or other skate or footwear and to enhance the braking effect with the rolling surface, as described herein. In yet other embodiments, the foot rest  1100  may have a partial or full coating, or other suitable application, of rubber, plastic, or other suitable material for enhancing the grip with the heeling apparatus  2000  or other skate or footwear and to enhance the braking effect with the rolling surface, as described herein. In yet other embodiments, the foot rest  1100  may have a braking structure, including a surface of rubber, plastic, or other suitable material, positioned at least partially adjacent to the bottom surface of the foot rest  1100  for enhancing the braking effect, as described herein, of the wheeled platform apparatus  1000  with the rolling surface. 
     Referring again to  FIGS. 25 ,  29 A,  29 B,  29 C,  29 D, and  31 , in some embodiments, the foot rest  1100  may include a mating structure  1102  for mating the foot rest  1100  with the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In some embodiments, the mating structure  1102  may be mounted adjacent to the foot rest  1100  or may be mounted within or at least partially within the foot rest  1100 . In some embodiments, the mating structure  1102  may be a first magnet for magnetically mating with a second magnet, or other magnetic structure, positioned adjacent to or partially within the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In other embodiments, the mating structure  1102  may be a male attachment projection for mating with a female attachment receptacle positioned adjacent to or partially within the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In other embodiments, the mating structure  1102  may be a female attachment receptacle for mating with a male attachment projection positioned adjacent to or partially within the forefoot portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. 
       FIGS. 22A ,  22 B,  24 ,  25 ,  26 ,  27 , and  31  illustrate one embodiment of the wheeled platform apparatus  1000  having a projection  1110  extending or angling from the platform  1010  at least partially within a plane passing through the platform  1010  for resting the forefoot, arch, heel, or other potion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , during use of the wheeled platform apparatus  1000 . The projection  1110  provides the user with the option of resting their chosen skate or footwear on the projection  1110  while rolling, resting, or performing tricks with the wheeled platform apparatus  1000 . In some embodiments, the projection  1110  extends downward from the front portion  1040 , center portion  1030 , or rear portion  1020  of the platform  1010  at an angle less than 180 degrees from a plane passing through the platform  1010  of the wheeled platform apparatus  1000 . In yet other embodiments, the projection  1110  extends upwardly from the front portion  1040 , center portion  1030 , or rear portion  1020  of the platform  1010 . 
     In some embodiments, the projection  1110  may be textured to enhance grip with the heeling apparatus  2000  or other footwear. In yet other embodiments, the projection  1110  may have a partial or full coating, or other suitable application, of rubber, plastic, or other suitable material for enhancing the grip with the heeling apparatus  2000  or other footwear. 
     Referring again to  FIGS. 25 AND 31 , in some embodiments, the projection  1110  may include a mating structure  1104  for mating the projection  1110  with the forefoot, arch, or heel portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In some embodiments, the mating structure  1104  may be mounted adjacent to the projection  1110  or may be mounted within or at least partially within the projection  1110 . In some embodiments, the mating structure  1104  may be a first magnet for magnetically mating with a second magnet, or other magnetic structure, positioned adjacent to or partially within the forefoot, arch, or heel portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In other embodiments, the mating structure  1104  may be a male attachment projection for mating with a female attachment receptacle positioned adjacent to or partially within the forefoot, arch, or heel portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. In other embodiments, the mating structure  1104  may be a female attachment receptacle for mating with a male attachment projection positioned adjacent to or partially within the forefoot, arch, or heel portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , while in resting or rolling position. 
     In yet other embodiments, a second projection  1120  may also be used in a similar fashion as the first projection  1110 , and may or may not be angled from the platform  1010 . In some embodiments, the second projection  1120  may include a mating structure  1106  that is used in a similar fashion to the mating structure  1104 . It should also be understood that the first projection  1110  and the second projection  1120  may be positioned at any desired location of the wheeled platform apparatus  1000 . 
       FIG. 38  illustrates one embodiment of the wheeled platform apparatus  1000  having a mid-chassis  1520  removably affixed to platform  1010 . In descriptions herein, the mid-chassis  1520  may interchangeably be referred to as the top portion of the platform  1010 . Mid-chassis  1520  may be removably affixed to the platform  1010  at least partially by screw, bolt, snap fit, tongue-and-groove, or other suitable fastening mechanism. The mid-chassis  1520  allows for interfacing with platform  1010  to, for example, increase the structural integrity of the apparatus  1000  and lower the costs of manufacturing, and may provide for mating, via snap fit, friction fit, magnetic fit, tongue-and-groove fit, screws, bolts, or other suitable mating means, with a deckplate  1510 . 
     Referring to  FIGS. 38 ,  49 , and  50 , in some embodiments, the attachment structure  1514 , which may be interchangeably referred to herein as attachment structure  1090 , is detachably connected by fasteners  1512 , or other suitable means, to a deckplate  1510 , which in some embodiments may be deckplate  1012 , directly to mid-chassis  1520 , directly to platform  1010 , or to any combination of deckplate  1510 , mid-chassis  1520 , or platform  1010 . In one embodiment, the attachment structure  1514  is formed to accommodate fasteners  1512 , axle structure  1516 , and tensioner  1518 . The top surface of the deckplate  1510  may include a recess  1519  for interfacing with a projection  1524  of attachment structure  1514  to facilitate rotation of the attachment structure relative to the longitudinal centerline of the deckplate  1514 , thereby allowing the user to position the heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010 , which in some embodiments may be at an angle offset from the rolling direction or the longitudinal centerline of the platform  1010  of the wheeled platform apparatus  1000 . For example positioning of the heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 15 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . In other embodiments, for example, positioning of the heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 45 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . Other angles are possible and are a matter of the user&#39;s preference. 
     In still other embodiments, the projection  1524  of the attachment structure  1514  may interface with the mid-chassis  1520  and/or the platform  1010 . In some embodiments, the axle structure  1516  is at least partially-secured to attachment structure  1514  by tensioner  1518 , such as a set-screw, mounting pin, or other suitable structure, and mates with a recessed heel opening, wheel mounting structure, and/or axle recess within the heel of a heeling apparatus  2000 . Said heel opening, wheel mounting structure, and/or axle recess may be implemented as that generally described above and/or illustrated in  FIGS. 2A ,  2 B,  3 A,  3 B,  5 ,  6 ,  9 , and  10 . 
     The attachment structure  1514  is preferably positioned in the rear portion of the top surface of the deckplate  1510  along the longitudinal centerline of the deckplate  1510 . However, in other embodiments, the attachment structure  1514  may be positioned anywhere upon the deckplate  1514  that allows for mating with the heeling apparatus  2000 . In some embodiments, the axle structure  1516  may be replaced by another axle structure  1516  of a different length, thereby allowing the axle structure  1516  to interface with variable sized heel openings, wheel mounting structures, and/or axle recesses which, as described above, cooperate with variable sized wheel and axle assemblies, of various embodiments of the heeling apparatus  2000 , including heeling apparatuses of different sizes. 
       FIGS. 38 ,  39 A,  39 B,  39 C,  49 , and  50  further illustrate one embodiment of the attachment structure  1514 . The perspective view of the attachment structure  1514  as shown in  FIG. 39A  illustrates a first fastener opening  1521  to allow insertion of a fastener  1512  for removably attaching said attachment structure  1514  to the deckplate  1510 . Also illustrated is a sleeve-like opening  1522  for accommodating axle structure  1516 , and a tensioner opening  1523  located on the top surface of the attachment structure  1514  to allow insertion of a tensioner  1518  for at least partially securing said axle structure  1516  within the sleeve-like opening  1522 . The tensioner opening  1523  may optionally include an insert operable to relieve stress caused by the tensioner  1518 , and may be comprised of metal, wood, plastic, polyurethane, ceramic, composite, or any other durable material. 
     In some embodiments, the attachment structure  1514  may further include a projection  1524  as illustrated in  FIG. 39B . The projection  1524  may be comprised of metal, ceramic, plastic, polyurethane, composite, wood, or any other durable material for interfacing with a recess  1519  in the top surface of the deckplate  1510  to facilitate rotation of the attachment structure  1514  relative to the longitudinal centerline of the deckplate  1510 . 
       FIGS. 39C and 44  illustrate one embodiment of the attachment structure  1514  illustrating the first fastener opening  1521 , a second fastener opening  1525 , the sleeve-like opening  1522 , and the projection  1524 . The second fastener opening  1525  is similar to the first fastener opening  1521  and allows insertion of a fastener  1512  for removably attaching said attachment structure  1514  to the deckplate  1510 . Both first fastener opening  1521  and second fastener opening  1525  may be non-circular (e.g., may be rectangular, oval, etc.) to allow for displacement of the attachment structure  1514 , such as rotational displacement, relative to the fastener  1512  and deckplate  1510 . Such displacement allows for flexibility in positioning the user&#39;s heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010 , which in some embodiments may be at an angle offset from the rolling direction or the longitudinal centerline of the platform  1010  of the wheeled platform apparatus  1000 , thereby resulting in improved handling, comfort of ride, and added safety. For example positioning of the heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 15 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . In other embodiments, for example, positioning of the heeling apparatus  2000  primarily along the longitudinal centerline of the platform  1010  may occur at an angle less than plus or minus 45 degrees from the rolling direction or the longitudinal centerline of the wheeled platform apparatus  1000 . Other angles are possible and are a matter of the user&#39;s preference. 
       FIGS. 40A ,  40 B,  40 C,  41 C, and  41 E illustrate another embodiment of the present invention, in which the mid-chassis  1520  includes a recess  1526  for storing objects. In yet other embodiments, the platform  1010  may include a recess  1526 .  FIG. 40A  illustrates the mid-chassis  1520  with a recess  1526  storing axle structures  1516  as an exemplary utilization of the recess  1526 . The recess may be concealed beneath, for example, a deckplate  1510  as illustrated in  FIG. 40B . The recess may also be concealed beneath, for example, a strap, lid, and/or other securing means, and may be used to store items such as additional axle structures, fasteners, tensioners, keys, or other personal objects. 
       FIGS. 41A ,  41 B,  41 C,  41 D,  41 E, and  41 F illustrate yet another embodiment of the present invention, in which a strap  1535  is removably coupled to the mid-chassis  1520  for removably coupling a non-wheeled or wheeled footwear, including a heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , external wheel assembly  2008 , or other wheeled skate, or a user&#39;s bare foot to the wheeled platform apparatus  1000 . The strap  1535  may be comprised of nylon, polyurethane, rubber, or any other durable material, and may be clasped, tied, hook-and-looped or otherwise fastened around or to the non-wheeled or wheeled footwear. As illustrated in  FIGS. 41A and 41B , the strap  1535  may be coupled between the mid-chassis  1520  and deckplate  1510 . In yet other embodiments, the strap  1535  may be coupled directly to the platform  1010 .  FIGS. 41C and 41E  illustrate the recess  1526  of mid-chassis  1520 , wherein the strap  1535  conceals the recess  1526 , thereby at least partially securing any personal objects stored within said recess  1526 .  FIG. 41D  illustrates the strap  1535  located on the top surface of the mid-chassis  1520 , and in some embodiments, concealing the recess  1526 , removably coupled thereto by the deckplate  1510 . 
       FIGS. 28 ,  29 A,  29 B,  29 C,  29 D,  29 E,  30 A,  30 B,  30 C, and  30 D illustrate a method for use of the wheeled platform apparatus  1000  on a surface by a user, wherein the user positions a first foot  1200  on the wheeled platform apparatus  1000  and moves on the surface in a first direction (i.e., rolling direction of the wheeled platform apparatus  1000 ) by placing at least a portion of a heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on a second foot  1210 , in contact with the surface and kicking or pushing the portion of the heeling apparatus  2000  or other skate or rolling apparatus from the surface to provide force in the first direction, as illustrated in  FIGS. 30A ,  30 B,  30 C, and  30 D. In other embodiments, forward force in the first direction may also be provided by using the heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on a second foot  1210 , in a “roller skating” manner (i.e., pushing the second foot  1210  outward and in a direction opposite of the intended rolling direction). The forward force causes the wheeled platform apparatus  1000  to roll on the surface in generally the first direction. 
     Referring again to  FIGS. 30A and 30D , another method for use of the wheeled platform apparatus  1000  on a surface by a user is illustrated, wherein a heeling apparatus  2000 , external wheel assembly  2008 , or similar rolling apparatus, having one or more wheels mounted or strapped adjacent to, partially within, or under the heel of the skate or rolling apparatus, may generate forward force in the first direction (i.e., rolling direction of the wheeled platform apparatus  1000 ) by placing the forefoot portion of the heeling apparatus  2000 , external wheel assembly  2008 , or similar rolling apparatus in contact with the surface and kicking or pushing forward from the surface. 
     Referring again to  FIGS. 29A ,  29 D, and  29 E, in other embodiments of the method of use of the wheeled platform apparatus  1000 , once the user is moving in combination with the wheeled platform apparatus  1000  and a heeling apparatus  2000  or external wheel assembly  2008 , worn on a second foot  1210 , the user may transition from moving on the surface to rolling on the surface by elevating the forefoot portion of the sole of the heeling apparatus  2000  or external wheel apparatus  2008  worn on the second foot  1210  above and out of contact with the surface used for rolling. 
     Referring again to  FIGS. 30B and 30C , another method for use of the wheeled platform apparatus  1000  on a surface by a user is illustrated, wherein a skate, such as a quad skate  2004 , inline skate  2006 , or similar apparatus having one or more wheels mounted or strapped adjacent to, partially within, or under at least the heel and forefoot of the skate, may generate forward force in the first direction (i.e., rolling direction of the wheeled platform apparatus  1000 ) by positioning the rolling direction of the skate at an angle offset from the first direction and pushing or kicking with the second foot  1210  in a direction offset from the first direction of the wheeled platform apparatus  1000  in a manner similar to “roller skating,” thereby generating a forward force in the first direction due to the application of force applied to the surface at an angle offset from the rolling direction of the skate. Referring again to  FIGS. 30B and 30C , the forward force in the first direction may be derived by placing a toe or heel brake or a non-rolling surface of the skate in contact with the surface and pushing off with the second foot  1210 . 
     Referring to  FIGS. 29A ,  29 B,  29 C,  29 D,  29 E,  42 ,  43 , and  51 , in other embodiments of the method of use of the wheeled platform apparatus  1000 , once the user is rolling in combination with the wheeled platform apparatus  1000  and the heeling apparatus  2000  or other footwear, skate, or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on a second foot  1210 , the user may transition from rolling on the surface to stopping on the surface by (1) placing at least a portion of the forefoot of the heeling apparatus  2000  or external wheel apparatus  2008  in contact with the surface, (2) elevating the forefoot portion of the heeling apparatus  2000 , external wheel apparatus  2008 , or other wheeled footwear having a heel brake to cause the heel brake, such as the rear brake  2002  of the heeling apparatus  2000  or external wheel apparatus  2008 , to interface with the surface causing a friction braking effect, (3) elevating the front portion of the wheeled platform apparatus  1000  thereby causing the foot rest  1100  to interface with the surface causing a friction braking effect, (4) elevating the heel portion of the quad skate  2004 , inline skate  2006 , or other wheeled footwear having a forefoot braking surface or structure, such as a toe-stop on a quad skate  2004  or inline skate  2006 , to cause the forefoot braking surface or structure to interface with the rolling surface causing a friction braking effect, and (5) dragging at least a portion of a non-rolling component of the footwear, worn on the second foot  1210 , thereby causing a friction braking effect between the non-rolling component of the footwear and the rolling surface. In other embodiments, as illustrated by  FIG. 43 , the transition from rolling on the surface to stopping on the surface may occur with the second foot  1210  positioned in front of the wheeled platform apparatus  1000 . In still other embodiments, as illustrated by  FIGS. 42 and 51 , the transition from rolling on the surface to stopping on the surface may occur with the second foot  1210  positioned behind the wheeled platform apparatus  1000 . In other embodiments, as illustrated by  FIG. 51 , the transition from rolling on the surface to stopping on the surface by dragging at least a portion of a non-rolling component of the footwear may occur by dragging at least a portion of the sole of the footwear, such as the inside edge of the sole, along the surface. 
     Referring again to  FIGS. 29A ,  29 B,  29 C,  29 D,  29 E,  42 , and  43 , in yet another embodiment of the method of use of the wheeled platform apparatus  1000 , rolling on the surface may include placing the heeling apparatus  2000  or other skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , which is worn on the second foot  1210 , at least partially in front of the wheeled platform apparatus  1000 , at least partially adjacent to either side of the wheeled platform apparatus  1000 , or at least partially behind the wheeled platform apparatus  1000 , such that the heeling apparatus  2000  or other skate or rolling apparatus is positioned in a manner operable to roll on the surface, which in some embodiments includes elevating the forefoot of the heeling apparatus  2000  or other skate or rolling apparatus in a manner operable to roll using the wheel in, under, or adjacent to the heel. 
     Referring again to  FIGS. 29A ,  29 B,  29 C,  29 D, and  29 E, another method for use of the wheeled platform apparatus  1000  on a surface by a user is illustrated, wherein at least a portion of the forefoot of a heeling apparatus  2000  or other skate or rolling apparatus, having one or more wheels mounted or strapped adjacent to, partially within, or under the heel of the skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on a second foot  1210 , may be elevated relative to the surface, where the forefoot of the heeling apparatus  2000  or other skate or rolling apparatus is positioned upon or adjacent to the foot rest  1100  of the wheeled platform apparatus  1000  while the one or more wheels mounted or strapped adjacent to, partially within, or under the heel of the heeling apparatus  2000  or other skate or rolling apparatus rolls on the surface. 
     Referring to  FIGS. 24 ,  25 , and  31 , other embodiments include a method for use of the wheeled platform apparatus  1000  on a surface by a user, wherein a portion, such as the forefoot or arch, of the a heeling apparatus  2000  or other skate or rolling apparatus, having one or more wheels mounted or strapped adjacent to, partially within, or under the skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on a second foot  1210 , may be elevated relative to the surface, where the elevated portion of the heeling apparatus  2000  or other skate or rolling apparatus is positioned upon or adjacent to the projection  1110  or  1120  of the wheeled platform apparatus  1000  while the one or more wheels mounted or strapped adjacent to, partially within, or under the heeling apparatus  2000  or other skate or rolling apparatus rolls on the surface. 
     Referring to  FIGS. 28 ,  29 A,  29 B,  29 C,  29 D,  29 E,  41 A,  41 B,  41 C,  41 D,  41 E,  41 F,  42 ,  43 ,  44 , and  48 , in other embodiments of the method of use of the wheeled platform apparatus  1000 , a non-wheeled or wheeled footwear, including a heeling apparatus  2000 , quad skate  2004 , inline skate  2006 , external wheel assembly  2008 , or other wheeled skate, is worn on the first foot  1200  and may removably interface with at least a portion of the wheeled platform apparatus  1000 , via attachment structure, binding, strap, magnets, or otherwise. 
     Referring to  FIG. 45 , in other embodiments of the method of use of the wheeled platform apparatus  1000 , a removable wheel is inserted into the opening in the heel portion of the sole of a heeling apparatus  2000  prior to rolling on the surface. 
     Referring again to  FIGS. 29A ,  29 B,  29 C,  29 D, and  29 E, in other embodiments, when used in conjunction with the wheeled platform apparatus  1000 , at least a portion of at least one wheel of a heeling apparatus  2000  or other skate or rolling apparatus, having one or more wheels mounted or strapped adjacent to, partially within, or under the skate or rolling apparatus, including a quad skate  2004 , an inline skate  2006 , or external wheel assembly  2008 , worn on the second foot  1210 , extends at least partially below the bottom of the sole of the heeling apparatus  2000  or other skate or rolling apparatus to contact the rolling surface, wherein the at least one wheel is operable to roll while supporting at least a portion of the weight of the user, as described above. 
     Thus, it is apparent that there has been provided, in accordance with the present invention, a wheeled platform apparatus and method. Although preferred embodiments have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of the present invention, even if some or all of the advantages identified above are not present. For example, the various elements or components may be combined or integrated in another system or certain features may not be implemented. 
     Also, the components, techniques, systems, sub-systems, layers, compositions and methods described and illustrated in the preferred embodiment as discrete or separate may be combined or integrated with other components, systems, modules, techniques, or methods without departing from the scope of the present invention. Other examples of changes, substitutions, and alterations are readily ascertainable by one skilled in the art and could be made without departing from the scope of the present invention.