Abstract:
An apparatus for protective headgear is disclosed together with a headgear assembly. The headgear is designed to attenuate shocks, blows and impacts delivered to the front, sides, and back of the head by dissipating the force through deflection, shock absorption, and movement of the structural materials. Reduction and attenuation of head impacts reduces head accelerations and forces that may result in concussions. Methods of using the headgear apparatus and assembly are disclosed.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present invention claims priority to U.S. Application No. 61/922,771, filed Dec. 31, 2013, and U.S. Application No. 61/926,393, filed Jan. 12, 2014, which are incorporated by reference herein for all purposes. 
     
    
     BACKGROUND 
       [0002]    Soccer is the last major-participation contact sport played in America which does not widely require an impact protective headgear to be worn by its players. Sport related concussion, traumatic brain injury and awareness of the dangers of repeated concussion have already created a rapidly growing market for elective headgear among soccer players at all levels. However, there is no commercially available headgear able to make claims of reducing the likelihood of concussion among users. The Center for Disease Control has identified the problem of sport concussion as having reached “epidemic level” in America, and soccer is among a handful of sport activities currently most responsible for those injuries. Among women and girls, soccer currently accounts for the greatest number of sport concussion and Traumatic Brain Injuries annually. The CDC estimates that a full 10% of unprotected soccer participants will experience at least one concussion injury within any given team soccer season. 
         [0003]    The headgear apparatus and assembly disclosed herein effectively raises the minimum blow necessary to cause the whiplash or revolution of the head generally credited as responsible for causing concussion or traumatic brain injuries. Further, as most soccer concussion injuries result from head-to-head player contact, the inventions disclosed herein will prove a significant reduction of impact force for both players involved in a head-to-head, even when only one is wearing the headgear. 
         [0004]    The headgear apparatus and assembly disclosed herein differs from what currently exists. Current contact sports headgear products use only foams to absorb impact, and the foams alone may not be sufficient to reduce rotation from shocks and impacts, which may cause whiplash of the head that results in the brain of the subject to strike the inner skull wall. Foam materials alone, worn against the head, can only reduce head rotation or acceleration from very small impacts. Larger impacts will still rotate the head and as if no headgear were present at all. 
       BRIEF SUMMARY 
       [0005]    An apparatus for protective headgear is disclosed together with a headgear assembly. The headgear is designed to attenuate shocks, blows and impacts delivered to the front, sides, and back of the head by dissipating the force through deflection, shock absorption, and movement of the structural materials. Reduction and attenuation of head impacts reduces head accelerations and forces that may result in concussions. Methods of using the headgear apparatus and assembly are disclosed. 
         [0006]    Disclosed in embodiments herein are an apparatus and assembly for headgear for use by participants in contact sports to reduce the incident of concussion among users by attenuating the force of impact to the head and therefore reducing the whiplash motion the causes or contributes to concussions and traumatic brain injuries. Embodiments of the inventions raise the minimum impact necessary for a contact sports player to suffer a concussion. Of course, embodiments disclosed herein may be used by any person in any field or occupation that may be at risk of experiencing head impacts, concussions or traumatic brain injury. 
         [0007]    Embodiments of the invention allow users wearing the headgear to receive a larger impact without the amount of rotation of the head that causes the brain to move within and to strike the inner, causing damage to the brain. In effect, the minimum blow necessary to cause head rotation is increased in comparison to when no headgear is worn. 
         [0008]    Embodiments include an apparatus for headgear comprising a base having an inner surface with an inner surface area and an outer surface with a recess; and a shell in contact with the recess, wherein the base includes at least one setoff with a contact area, the setoff disposed on the inner surface, and wherein the contact area of the setoff is configured to contact a user&#39;s head. 
         [0009]    In an embodiment, the base of the apparatus includes more than one recess and more than one shell, and wherein each shell is in contact with a recess. 
         [0010]    In an embodiment, the base includes at least one dowel extending outward from the outer surface, and the shell includes at least one opening configured to accept the at least one dowel. 
         [0011]    In an embodiment, the recess of the outer surface includes a floor and at least one wall, and the shell is configured to contact at least a portion of the floor and a portion of the at least one wall. 
         [0012]    In an embodiment, the contact area the contact area is less than 75%, 70%, 60%, 50%, 40%, 30%, 20%, 10% or 5% of the inner surface area. 
         [0013]    In an embodiment, the total contact area of all setoffs is less than 75%, 70%, 60%, 50%, 40%, 30%, 20%, 10% or 5% of the total inner surface area of all base inner surfaces. 
         [0014]    In an embodiment, an apparatus of the invention the apparatus covers, protects or shields at least a portion of the forehead, a portion of the sides of the head, and a portion of the back of the head. 
         [0015]    In an embodiment, an apparatus of the invention does not cover, protect or shield the top of the head. 
         [0016]    In an embodiment, at least a portion of a base of a segment is hollow. 
         [0017]    In an embodiment, an apparatus includes a space between the base and the shell when the shell is seated in the recess. 
         [0018]    Embodiments disclosed herein include a headgear assembly comprising one or more segments, each segment having a base having an inner surface with an inner surface area and an outer surface with a recess, and a shell in contact with the recess, wherein the base includes at least one setoff with a contact area, the setoff disposed on the inner surface, and wherein the contact area of the setoff is configured to contact a user&#39;s head; and at least one strap connecting the one or more segments. 
         [0019]    In an embodiment, a headgear assembly includes a strap that passes through a slot in the shell. 
         [0020]    In an embodiment, a headgear assembly includes a strap that passes through a slot in the base and the shell. 
         [0021]    In an embodiment, a headgear assembly covers, protects or shields at least a portion of the forehead, a portion of the sides of the head, and a portion of the back of the head. 
         [0022]    In an embodiment, a headgear assembly attenuates an impact aimed at or an impact on the user&#39;s head. 
         [0023]    Embodiments disclosed herein include a method of attenuating an impact aimed at or an impact on a user&#39;s head comprising placing a headgear assembly onto a user&#39;s head, wherein the headgear assembly includes one or more segments, each segment having a base having an inner surface with an inner surface area and an outer surface with a recess, and a shell in contact with the recess, wherein the base includes at least one setoff with a contact area, the setoff disposed on the inner surface, and wherein the contact area of the setoff is configured to contact a user&#39;s head; and at least one strap connecting the one or more segments, adjusting the headgear assembly to cover at least a portion of the forehead, a portion of the sides of the head, and a portion of the back of the head; and the strap connecting the one or more segments so that the contact areas are in contact with the head. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    In the detailed description that follows, embodiments are described as illustrations only since various changes and modifications will become apparent to those skilled in the art from the following detailed description. 
           [0025]      FIG. 1  illustrates a user wearing a headgear assembly on the user&#39;s head in an embodiment. 
           [0026]      FIG. 2  illustrates a headgear assembly in an embodiment. 
           [0027]      FIG. 3  illustrates a segment of the apparatus in an embodiment. 
           [0028]      FIG. 4  illustrates an exploded view of a segment of the apparatus in an embodiment. 
           [0029]      FIGS. 5A and 5B  illustrate exploded section views through a base and a shell in an embodiment. 
           [0030]      FIG. 6  illustrates an inner surface of a base and a strap in an embodiment. 
           [0031]      FIG. 7  illustrates a segment of the apparatus in an embodiment. 
           [0032]      FIG. 8  illustrates the inner surface of a base in an embodiment. 
           [0033]      FIGS. 9A and 9B  illustrate a segment and a strap of the apparatus in an embodiment. 
           [0034]      FIG. 10  illustrates a shell of a segment of the apparatus in an embodiment. 
           [0035]      FIGS. 11 and 12  illustrate a base of a segment of the apparatus in an embodiment. 
           [0036]      FIG. 13  illustrates an exploded section view through a base and a shell in an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0037]    In the following detailed description, reference is made to the accompanying drawings, which form a part of the description. The example embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings, may be arranged, substituted, combined, separated, and designed in a wide variety of different configurations. 
         [0038]    Embodiments of the invention relate to a headgear assembly that includes one or more segments that may be connected with one or more straps. The straps may connect two segments or more than two segments. The straps may be adjustable so that the headgear fits comfortably on the user&#39;s head and fits snug enough for the user to move and participate in his sport of choice. 
         [0039]    It will be understood that in embodiments the general outline, shape and contour of each segment may vary. The segments include a base and a shell, in which the base has an inner surface and an outer surface with a recess. The shell is in contact with, and may be seated in the recess of the base. The base includes at least one setoff that extends inward from the inner surface of the base, and the end or contact area of the setoff is in contact with the user&#39;s head. The base may have more than one recess on its outer surface, in which case a shell is matched to each recess. The base may also have one or more hollow spaces within its thickness, or the hollow space may extend to the edge of the base. 
         [0040]    In embodiments, the shape of the recess and the shape of the shell are matched so that the shell can be seated in the recess. The base and the shell can also be aligned by including a dowel that extends outward from the outer surface or recess of the base. The dowel fits inside a matching hold in the shell. 
         [0041]    In embodiments, the recess of the outer surface includes a floor and at least one wall, and the shell contacts the wall and the floor. The shell may include a rim that extends inward from the inner surface of the shell. The rim may match the walls of the base and contact both the base and the wall. When the shell is seated in the recess, the base and shell form a space between them. The space allows increased deflection and dissipation of impact force. 
         [0042]    With regard to the disclosure herein, it will be understood that in embodiments, a headgear assembly includes one or more segments that may be connected with one or more straps. The segments include a base and a shell, in which the base may be made from any deformable elastic material, such as foam, rubber, injection molded ethylene vinyl acetate (EVA) rubber, or other rubber-like materials by way of non-limiting examples, and in which the shell may be made from any plastic or composite material, such as injection molded LDPE plastic or other low or medium density plastics by way of non-limiting examples. The base and shell may be formed from materials of different colors, as well as materials that are easy to clean and maintain in embodiments. 
         [0043]    In embodiments disclosed herein, the base touches or is in contact with the user&#39;s head at designed points and intervals. The shell bridges the points and intervals in the base. Nylon and/or elastic straps are routed through eyelets in in the base and the shell to hold the structure together, and to adjust the headgear for different sizes of heads of end users. In embodiments, the shell and the base may be held together with fasteners or doweled joints. 
         [0044]    With regard to the disclosure herein, it will be understood that in embodiments, the headgear assembly is designed to dissipate the force associated with a blow or impact to the head and to attenuate the force of the impact or shock. As the impact force connects with the shell, energy is dissipated in the deflection of the shell, the movement between the shell and the base, movement between segments of the headgear assembly, and deflection of the base material before the remaining force impacts the head through the limited contact areas. With reduced impact forces, head acceleration is also moderated, attenuated, or otherwise reduced. 
         [0045]    In embodiments, the base is made from softer material relative to the shell, and the base touches the head of the end user in a limited number of spots over the surface of the head, while the shell rests on the base but does not touch the head. In such embodiments, a blow to the outward facing shell does not contact the head directly, and the force of the impact is transferred to the head through the shell, which bridges the limited number of spots of the base that contact the head. During the transfer of the force of impact, in embodiments the force is further reduced by the softer material of the base. 
         [0046]    In embodiments, the base and the shell may be injection molded and formed to fit together, such that the base includes a recess that is designed to receive the shell. The shell may be formed in embodiments to act as protective bridges over key portions of the user&#39;s head. In embodiments, straps are threaded through confluences of the base and the shell and fixed to hold the structure together. In some embodiments, the headgear is assembled by hand and/or machine stitching. 
         [0047]    In embodiments, the base has an inner surface area from which setoffs extend inward to contact the head. The contact area of the base is thus limited to the area of the setoffs that contact the head. In embodiments, the setoffs may include a flat contact surface or a contoured contact surface, in which case the contact surface area may be estimated by taking the area of the setoff at the inner surface. In embodiments, the total area of the setoff contact areas is less than 50% of the total inner surface area; less than 40% of the total inner surface area; less than 30% of the total inner surface area; less than 20% of the total inner surface area less than 10% of the total inner surface area; or less than 5% of the total inner surface area. By raising the majority of the base and all of the shell off of the user&#39;s head, an absence of material is created under MOST of the total inner surface areas of the base or bases so that blows to the headgear product will be transferred to the surface of the head only where the base is engineered to touch the head. The ability of the headgear base and shell to flex also reduces impact force to the head. 
         [0048]    Embodiments of the invention disclosed herein are not limited to soccer players, and configurations of the base and shell, and of the setoffs, may be customized for different sports or disciplines. A common head blow to a soccer player may be different or differently directed than a common head blow to a rugby player, and strategic designs may be implemented for different conditions of use. 
         [0049]    With regard to the disclosure herein, it will be understood that in embodiments, the headgear is designed to cover, protect or shield at least a portion of each side of the head, a portion of the back of the head, and a portion of the front of the head, but not the top of the head. In embodiments, the contact areas of the base that transmit impacts to the head are designed and located to coincide with at least a portion of the squamous and lamboidal sutures. 
         [0050]    Embodiments of the invention also relate to a method of attenuating, moderating or reducing the force of an impact to a user&#39;s head by placing a headgear apparatus or assembly of the disclosure herein on the user&#39;s head, adjusting the headgear apparatus or assembly to cover, protect or shield at least a portion of each side of the head, a portion of the back of the head, and a portion of the front of the head, but not the top of the head, and adjusting one or more straps connecting the one or more segments so that contact areas are in touch or contact with the user&#39;s head. Placement and orientation of the headgear can be guided by product packaging that includes photographs or illustrations, and written instructions. Written, and photographed or illustrated instructions, for adjusting and tightening the headgear for a secure and comfortable fit can also be included in the product packaging. 
         [0051]      FIG. 1  illustrates a user wearing headgear assembly  200  on head  100  in an embodiment. The top of the user&#39;s head is estimated by line  110 . Line  110  is shown for illustrative purposes and not to define the exact location of the area on top of the head, however, as shown in the embodiment, headgear assembly  200  does not cover, protect or shield at least a portion of the top of head  100 . The headgear assembly does not cover the eyes or reduce line of sight in an embodiment. 
         [0052]    In an embodiment, headgear assembly  200  may include a number of segments that are connected by one or more straps  800 . In the embodiment illustrated in  FIG. 1 , headgear assembly  200  includes segments that cover, protect or shield at least a portion of each side of the head, a portion of the back of the head, and a portion of the front of the head from head impacts. In an embodiment, headgear assembly  200  reduces the force of head impacts and reduces resultant head accelerations. 
         [0053]    In an embodiment, segments that cover, protect or shield the front of the head may be configured to cover, protect or shield at least a portion of the head corresponding to the forehead, the position of the frontal lobe, the frontal bone, and/or the squamous suture. 
         [0054]    In an embodiment, segments that cover, protect or shield the side of the head may be configured to cover, protect or shield at least a portion of the head corresponding to the position of the temporal lobe, the temporal bone, and/or the squamous suture. In an embodiment, segments that cover, protect or shield the side of the head may be configured to cover, protect or shield all or a portion of an ear. 
         [0055]    In an embodiment, segments that cover, protect or shield the back of the head may be configured to cover at least a portion of the head corresponding to the position of the occipital lobe, the occipital bone, and/or the lamboidal suture. 
         [0056]    In an embodiment, headgear assembly  200  includes one or more straps  800 . Straps  800  may be formed from nylon or elastic strapping or webbing. In an embodiment, straps  800  include hook and loop fasteners that allow the straps to be adjusted, as well as closures, strap end pieces and other hardware known in the art. 
         [0057]      FIG. 2  illustrates in more detail headgear assembly  200  in an embodiment. In an implementation, headgear assembly  200  includes segments  210 ,  220 ,  230  and  240  and straps  810 ,  820 ,  830  and  840 , in which segment  210  is connected to segment  220  with strap  820 ; segment  220  is connected to segment  240  with strap  830 ; segment  240  is connected to segment  230  with strap  840 . Of course, segments  210 ,  220 ,  230  and  240  may be connected with only one strap, with two straps, with three straps, and with more than three straps. In an embodiment, segments  210 ,  220 ,  230  and  240  are contoured or molded as necessary to fit comfortably against head  100 . 
         [0058]    In  FIG. 2 , segment  210  covers, protects or shields at least a portion of the front of head  100  in an embodiment; segment  220  covers, protects or shields at least a portion of the left side of head  100  in an embodiment; segment  230  covers, protects or shields at least a portion of the right side of head  100  in an embodiment; and segment  240  covers, protects or shields at least a portion of the back of head  100  in an embodiment. At least a portion of the top of head  100  is not covered, protected, or shielded. 
         [0059]      FIG. 3  illustrates segment  210 , which covers, protects or shields at least a portion of the front of head  100  in an embodiment. Segment  210  includes base  310  and shell  340  in an embodiment. Eyelets are openings in base  310 , shell  340 , or both that permit straps  810  and  820  to pass through base  310 , shell  340 , or both in an embodiment. 
         [0060]      FIG. 4  illustrates an exploded view of segment  210  without straps  810  and  820  in an embodiment. Base  310  includes dowels  312 , eyelets  314 , vent holes  316  in an embodiment. Shell  340  includes holes  342 , eyelets  344 , vent holes  346  and optional decorative grooves  348  in an embodiment. In embodiments, dowels  312  are circular, but in other embodiments dowels  312  may be oval or other geometric shapes that match holes  342 . 
         [0061]      FIG. 5A  illustrates a section view through base  310  and shell  340  in an embodiment. It will be understood that  FIG. 5A  illustrates base  310  and shell  340  without contour, however, segment  210  may be contoured in more than one direction to match the contour of head  110 . Base  310  includes setoffs  318 , each of which includes contact area  352  in an embodiment. Setoffs  318  may be integral to base  310  and formed from the same material in an embodiment. In an embodiment, the area of contact areas  352  may be estimated as the cross section of setoffs  318  at inner surface  330  as represented by dashed lines  354 . 
         [0062]    Base  310  also includes recess  320 , which includes floor  322  and at least one wall  324  in an embodiment. Shell  340  includes optional groove  348 , and optional rim  350  in an embodiment. In an embodiment, rim  350  extends inward from the edges of shell  340  as represented by dashed lines  356 . Rim  350  is configured to fit into recess  320  and contact wall  324  when seated in the recess in an embodiment. Rim  350  may also contact floor  322  in an embodiment. In an embodiment, when shell  340  having rim  350  is seated in recess  320 , a space is formed between base  310  and shell  340 . In an embodiment, setoffs  318  are located on the inner surface such that at least a portion of the setoff is located inward from at least a portion of rim  350 . Impact force on shell  340  is thus passed through rim  350 , base  310 , setoff  318  and contact area  352  to head  110  in an embodiment, and rim  350  may be described as bridging setoffs  318 . 
         [0063]    In an alternative embodiment, shell  340  without rim  350  is shaped to fit into recess  320 . 
         [0064]      FIG. 5B  illustrates a section view through base  310  and shell  340  in an embodiment. It will be understood that  FIG. 5B  illustrates base  310  and shell  340  without contour, however, segment  210  may be contoured in more than one direction to match the contour of head  110 . Base  310  includes dowel  312 , which extends outward from floor  322  in an embodiment. Base  310  also includes recess  320 , which includes floor  322  and at least one wall  324  in an embodiment. Shell  340  includes holes  342 , and optional rim  350  in an embodiment. In an embodiment, rim  350  extends inward from the edges of shell  340 . Rim  350  is configured to fit into recess  320  and contact wall  324  when seated in the recess in an embodiment. Rim  350  may also contact floor  322  in an embodiment. In an embodiment, when shell  340  having rim  350  is seated in recess  320 , a space is formed between base  310  and shell  340 . In an alternative embodiment, shell  340  is shaped to fit into recess  320 . 
         [0065]    In  FIG. 5B , dowel  312  is configured to pass through hole  342  to assist in aligning base  310  with shell  340 . Dowel  312  may be integral to base  310  and formed from the same material. 
         [0066]      FIG. 6  illustrates the inner surface of base  310  and strap  810  in an embodiment. 
         [0067]    The inner surface of base  310  has surface area  330 . Setoffs  318  extending inward from surface area  330  are disposed on, or integral to, base  310  and may be formed from the same material in an embodiment. In an embodiment, base  310  includes vent holes  316  and eyelet  314 , and setoffs include contact areas  352  in an embodiment. Contact areas may be flat or designed to deform to contact head  100  in embodiments. In an embodiment in which the contact areas are shaped to deform in contact with head  100 , the area of the contact area may be assumed to be based on the cross-sectional area of setoff  318  at inner surface  330 . 
         [0068]    In an embodiment, the total area of the setoff contact areas is less than 50% of the inner surface area. In an embodiment, the total area of the setoff contact areas is less than 40% of the inner surface area. In an embodiment, the total area of the setoff contact areas is less than 30% of the inner surface area. In an embodiment, the total area of the setoff contact areas is less than 20% of the inner surface area. In an embodiment, the total area of the setoff contact areas is less than 10% of the inner surface area. In an embodiment, the total area of the setoff contact areas is less than 5% of the inner surface area. 
         [0069]      FIG. 7  illustrates segment  220 , which covers, protects or shields at least a portion of the left side of head  100  in an embodiment. Segment  220  includes base  410  and shell  440  in an embodiment. Eyelets are openings in base  410 , shell  440 , or both that permit straps  820  and  830  to pass through base  410 , shell  440 , or both in an embodiment. In an embodiment, strap  820  passes through eyelet  444  in shell  440  and a matching eyelet in base  410 , while strap  830  passes through one or more eyelets  444  (not shown) only in shell  440 . In an embodiment, strap  830  includes an end having the loop portion of a hook and loop fastener, with the end fixed to shell  440  with fasteners, glue, or other means known in the art, while closure  834  includes the hook portion of a fastener (not shown) affixed to the back of closure  834 . In embodiments, closure  834  may be sewn into or tied to the fabric of the strap, and closure  834  may include a window  832  into which an identification or decoration may be inserted. Shell  440  may also include vent holes  446  in an embodiment. 
         [0070]      FIG. 8  illustrates the inner surface of base  410  without strap  810  in an embodiment. The inner surface of base  410  has surface area  430 . Setoffs  418  extending inward from surface area  430  are disposed on, or integral to, base  410  and may be formed from the same material in an embodiment. In an embodiment, base  410  includes vent holes  416  and eyelet  414 , and setoffs include contact areas  452  in an embodiment. Contact areas may be flat or designed to deform to contact head  100  in embodiments. In an embodiment in which the contact areas are shaped to deform in contact with head  100 , the area of the contact area may be assumed to be based on the cross-sectional area of setoff  418  at inner surface  430 . 
         [0071]    In an embodiment, base  410  and shell  440  may be connected with fastener  420 , which extends through both base  410  and shell  440 . 
         [0072]      FIG. 9A  illustrates segment  230 , which covers, protects or shields at least a portion of the right side of head  100  in an embodiment. Segment  230  includes base  510  and shell  540  in an embodiment. Eyelets are openings in base  510 , shell  540 , or both that permit straps  810  and  840  to pass through base  510 , shell  540 , or both in an embodiment. In an embodiment, strap  810  passes through eyelet  544  (not shown) in shell  540  and a matching eyelet in base  510 , while strap  840  passes through one or more eyelets  544  (not shown) only in shell  540 . In an embodiment, strap  840  includes an end having the loop portion of a hook and loop fastener, with the end fixed to shell  540  with fasteners, glue, or other means known in the art, while closure  844  includes the hook portion of a fastener (not shown) affixed to the back of closure  844 . In embodiments, closure  844  may be sewn into or tied to the fabric of the strap, and closure  844  may include a window  842  into which an identification or decoration may be inserted. Shell  540  may also include vent holes  546  in an embodiment. 
         [0073]      FIG. 9B  illustrates segment  230  with strap  840  in an open position in an embodiment. In an embodiment, strap  810  passes through eyelet  548  in shell  540 , which has a matching eyelet in base  510  through which strap  810  also passes through. The end of strap  840  is affixed to shell  540  with fasteners  836  in an embodiment. Strap  840  also passes through two eyelets  544  in shell  540 , further securing the strap to shell  540  in an embodiment. The free end of strap  840  also passes through an eyelet in segment  240  (not shown) such that force may be applied to pull closure  844  forward to adjust headgear assembly  200  on head  100 . 
         [0074]      FIG. 10  illustrates a shell of segment  240 , which covers, protects or shields at least a portion of the back of head  100  in an embodiment. Shell  740  includes holes  742 , eyelets  744 , vent holes  746 , optional opening  756  and optional decorative grooves  748  in an embodiment. In an embodiment, optional strap  750  may be affixed to the shell with snap fasteners and provide additional adjustment. 
         [0075]      FIG. 11  illustrates the outer surface of base  710 , which includes dowels  712  that fit into holes  742  in shell  740 , eyelets  714 , vent holes  716  and optional opening  754 .  FIG. 12  illustrates the inner surface a base of segment  240  in an embodiment. Base  710  includes eyelets  714 , vent holes  716 , setoffs  718 , opening  754  and contact areas  752  in an embodiment. 
         [0076]      FIG. 13  illustrates an exploded section view through base  710  and shell  740  of segment  240  in an embodiment. Base  710  includes dowel  712  that fits into hole  742  in shell  740 , opening  754 , and recess  720  with floor  722  and walls  724  in an embodiment. Shell  740  includes optional rim  750  and hole  742  through which dowel  712  extends when shell  740  is in contact with or seated in recess  720  in an embodiment. In an embodiment, rim  750  extends inward from the edges of shell  740  as represented by dashed lines  758 . Floor  722  circles opening  754 , and two walls  72   
         [0000]      4  are shown in  FIG. 13 , one wall around the approximate edge of the base and one defining the edge of opening  754  in an embodiment. 
         [0077]    From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting.