Patent Publication Number: US-11020309-B1

Title: Adjustable slip resistant walking surface with cleats for removable attachment to a mobility aid

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/207,432 filed Dec. 3, 2018, which is a continuation-in-part of U.S. patent application Ser. No. 15/627,728 filed Jun. 20, 2017 which is a continuation-in-part of U.S. application Ser. No. 14/697,472 filed Apr. 27, 2015 which claims the benefit of U.S. Provisional Application No. 61/986,772 filed Apr. 30, 2014, all of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates in general to assisting individuals in their mobility and walking, and particularly to providing secure footing for individuals using mobility aids, such as walkers, rolling walkers or rollators, and wheelchairs on slippery surfaces. 
     BACKGROUND OF THE INVENTION 
     Walking or mobility aids are used by many people. Many elderly people use canes or walkers to provide needed stability and to prevent falling. Walkers have been developed that have four wheels and even provide the convenience of a seat and brakes. The walkers often fold for easy transport and to be readily available when needed. Walkers have greatly facilitated the mobility of many individuals, but they are often of little help in slippery conditions. For example on wet, snowy, or icy surfaces a walker provides no help in preventing a person&#39;s foot from slipping and causing a fall. Similar problems are encountered when using a wheelchair. The person pushing a wheel chair often needs to walk on a slipper surface. Therefore, there is a need for a device that can easily be use with a mobility aid, such as a walker, rolling walker or rollator, or wheelchair and that assures that the user has secure footing always under their feet as the mobility aid is moved and the user steps forward. 
     SUMMARY OF THE INVENTION 
     The present invention provides an attachment to a mobility aid, inducing a conventional or standard walker that provides a slip resistant surface that is automatically positioned under the user&#39;s foot as the walker is advanced or moved forward. Movable slip resistant surfaces are attached to support bars which are removably attached to a frame of a walker. The slip resistant surfaces are attached to a retraction means for selectively pulling the slip resistant surfaces towards the walker when the pressure of a user&#39;s foot is removed. As the user moves the walker forward the slip resistant surfaces are alternately moved into position under the user&#39;s foot by the retraction means for selectively pulling the slip resistant surface towards the walker. The attachment can be folded and closed to be positioned out of the way on the walker or removed and stored until needed. 
     In another embodiment of the present invention a modular system is used permitting attachment to a variety of different mobility aids, such as a walker, rolling walker or rollator, or wheelchair. An attachment bracket is attached on opposing sides of the mobility aid. A retractable slip resistant surface and cleat assembly is removably attached to each of the attachment brackets. The attachment brackets may have an intermediate pivot to facilitate folding with the mobility aid when the mobility aid is folded or collapsed. 
     In yet another embodiment of the present invention a retractable slip resistant surface attachment comprising an attachment panel with a sliding channel bracket holding a slide panel with attached slide wheels. The sliding channel bracket is selectively positioned longitudinally along the attachment panel. This permits the slip resistant surface to be moved backward and forward closer to and further away from the mobility aid so as to accommodate the stride of the user. 
     It is an object of the present invention to provide secure footing for a user of a walker on slippery surfaces, such as when walking in wet, icy, or snowy conditions. 
     It is another object of the present invention that is easy to use and attach to a walker. 
     It is an advantage of the present invention that it can be attached to an existing walker without the need to modify the walker. 
     It is another advantage of the present invention that it can be easily folded to be positioned out of the way on the walker when not in use. 
     Is a feature of the present invention that a retractable cord automatically positions a slip resistant surface under a user&#39;s foot. 
     It is another feature of the present invention that the slip resistant surfaces move independently from one another. 
     It is another feature of the present invention that the retractable cord can be selectively detached from the slip resistant surface permitting the slip resistant surface to be folded and closed to be compactly stored. 
     It is an object of an embodiment of the present invention to provide a modular or universal attachment system adapted to attach to a variety of mobility aids for receiving a retractable slip resistant surface and cleat assembly. 
     It is an advantage of an embodiment of the present invention that an attachment bracket may remain on the mobility aid with the retractable slip resistant surface and cleat assembly easily installed or removed as desired. 
     It is a feature of an embodiment of the present invention that the retractable slip resistant surface and cleat assembly slides in place and locks into an attachment bracket attached to the mobility aid. 
     It is another feature of an embodiment of the present invention that the attachment bracket has an intermediate pivot permitting it to fold with the folding or collapsing of the mobility aid. 
     It is an object of another embodiment of the present invention that the retractable slip resistant surface and cleat assembly can provide secure footing for a user. 
     It is an advantage of another embodiment of the present invention that the retractable slip resistant surface and cleat assembly can selectively slide along or grip the ground. 
     It is a feature of another embodiment of the present invention that the cleats are engaged with the ground when a user steps on the retractable slip resistant surface and disengaged with the ground when a user raises their foot. 
     It is an object of yet another embodiment of the present invention to provide adjustability to accommodate a user. 
     It is an advantage of yet another embedment of the present invention that it can easily be attached to the mobility aid in both a use and storage position. 
     It is a feature of yet another embodiment of the present invention that the slip resistant surface is selectively positioned longitudinally relative to the mobility aid. 
     These and other objects, advantages, and features will become more readily apparent in view of the following more detailed discussion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  schematically illustrates an embodiment of the present invention. 
         FIG. 2  illustrates use of a walker by a user with the present invention attached. 
         FIG. 3  is a plan view illustrating the present invention. 
         FIG. 4  is a side elevational view illustrating the present invention. 
         FIG. 5  is a plan view illustrating another embodiment of the present invention. 
         FIG. 6  is a perspective view schematically illustrating another embodiment of the present invention. 
         FIG. 7  is a plan view schematically illustrating the embodiment illustrated in  FIG. 6 . 
         FIG. 8  is a plan view of one of the slip resistant surfaces illustrated in  FIGS. 6-7  showing attachment of cleats. 
         FIG. 9  is a cross section taken along line  9 - 9  in  FIG. 8 . 
         FIG. 10A  is a perspective view illustrating an embodiment of the present invention having slip resistant retractable surfaces attachment in an open or ready to use position. 
         FIG. 10B  is a perspective view of the embodiment of the present invention illustrated in  FIG. 10A  with one slip resistant surface folded up. 
         FIG. 10C  is a perspective view of the embodiment of the present invention illustrated in  FIGS. 10A-B  with the slip resistant surfaces folded up and partially closed in a stored position. 
         FIGS. 11A-F  schematically illustrates the operation of the present invention illustrated in  FIGS. 10A-C . 
         FIG. 12A  schematically illustrates an attachment bracket attached to the inside of legs of a mobility aid. 
         FIG. 12B  schematically illustrates an attachment bracket attached between or on the outside of legs of a mobility aid. 
         FIG. 13  schematically illustrates a plan view of the present invention comprising the attachment bracket attached to a mobility aid and the retracting slip resistant surface and cleat assembly coupling to the attachment bracket. 
         FIG. 14  is a cross section taken along line  14 - 14  of the attachment bracket. 
         FIG. 15  is a cross section taken along line  15 - 15  of a slide assembly of the retractable slip resistant surface and cleat assembly. 
         FIG. 16  schematically illustrates a plan view of one of the retractable slip resistant surface and cleat assemblies. 
         FIG. 17  schematically illustrates an elevational view of a slip resistant surface and cleat head. 
         FIG. 18  schematically illustrates an elevational view of another embodiment of a slip resistant surface and cleat head. 
         FIG. 19  schematically illustrates an elevation a view of yet another embodiment of the slip resistant surface and cleat head. 
         FIG. 20  is a perspective view schematically illustrating another embedment of the present invention that provides lateral adjustment. 
         FIG. 21  is an elevational view schematically illustrating the embodiment illustrated in  FIG. 20 . 
         FIG. 22  is a plan view schematically illustrating the embodiment illustrated in  FIGS. 20 and 21 . 
         FIG. 23  is an elevational schematic view illustrating an alternate shape for the attachment panel of the embodiment illustrated in  FIGS. 20-22 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A walker, is generally used for individuals that may have difficulty walking and require some additional support to prevent falling. The present invention provides secure footing and improved stability for an individual using a walker on a slippery surface. At times, a walker may need to be used on surfaces that are wet, icy, slippery or uneven. When a walker is used in conditions where the walking surface may be slippery, such as when the walking surface is wet or icy, an individual having to step directly on the slippery surface may be much more prone to slipping or falling despite the use of the walker. The present invention provides a solution to the problem of using a walker on a slippery surface. 
       FIG. 1  schematically illustrates the present invention attached to a walker  10 . A slip resistant surface attachment  12  is attached to a leg  16  of the walker  10  with an attachment clip or means for attaching  14 . The attachment  12  comprises a roller or cylinder  18  and a slip resistant surface or pad  20  and  22 . The walker  10  may have wheels  24 . 
     The attachment  12  is securely connected to the walker  10  by the attachment clips  14  and may be easily removed and stored when not needed. Preferably, there are two slip resistant surfaces  20 ,  22  that move independently corresponding to each foot of the user. The slip resistant surfaces  20 ,  22  are rolled up on the roller or cylinder  18 . An internal spring may be used with a ratcheting mechanism, such as used in a common window shade, to extend and retract the slip resistant surfaces  20 ,  22 . Additionally, the roller or cylinder  18  may be bifurcated or made up of two individual rollers or cylinders that rotate independently so that the two slip resistant surfaces  20 ,  22  may be moved independently following the movement of each of the user&#39;s feet. 
     The present invention provides a device that greatly improves the stability of a user using a walker on a wet, slippery, or icy surface. The present invention assures that a user is always walking on a slip resistant surface. Means may be used for adjusting the tension or force in which the slip resistant surface is extended or retracted. The slip resistant surface may also be rolled up and detached from the walker for convenient storage when not needed. A knob may be used to assist rolling up the slip resistant surface onto the roller or cylinder. A locking device may also be used to prevent movement of the slip resistant surface from rolling and unrolling on the roller or cylinder. 
       FIG. 2  more clearly illustrates use of the present invention by a user and the placement of a user&#39;s foot on one of the slip resistant surfaces  22 . In  FIG. 2 , the slip resistant surface attachment  12  is attached to a horizontal bar  26  of the walker with the attachment clip or means for attaching  14 . As the user walks and placing their foot on one of the slip resistant surfaces  20  and  22 , and advances the walker forward the slip resistant surfaces  20  and  22  will extend and retract following the user&#39;s feet. This may be accomplished by a bias spring and a ratchet mechanism incorporated within the roller  18  such that when pressure by the user&#39;s foot is applied to the slip resistant surface  20  or  22 , it will extend and when pressure is released by movement of the user&#39;s foot it will retract a predetermined distance to become positioned for the user&#39;s next step. 
       FIG. 3  is a plan view illustrating the walker  10  with the attachment  12  attached thereto.  FIG. 3  illustrates the different amount of retraction and extension of the slip resistant surfaces  20  and  22 . The movement of the slip resistant surfaces  20  and  22  are represented by the arrows. 
       FIG. 4  is a side elevational view illustrating the slip resistant surface  22  rolled up on the roller or cylinder  18  in the direction of the arrow placed thereon.  FIG. 4  also illustrates an embodiment that has cleats  28  placed on the slip resistant surface  22  on either the top or bottom surface or both. Any form or shape of cleat  28  may be used. Additionally, the slip resistant surface maybe made of rubber, plastic, fabric or any flexible material that provides a slip resistant surface and that is capable of being rolled. 
       FIG. 5  illustrates another embodiment of the present invention utilizing a spring or other equivalent means for retracting and extending or moving the slip resistant surfaces  120  and  122 . In this embodiment the slip resistant surface attachment  112  comprises a bar or cylinder  118  having attachment clips  114  placed on either end. Attached to the bar  118  intermediate the ends thereof are spring means for extending and retracting the slip resistant surfaces  120  and  122  and permitting them to move in the direction of the arrows. Accordingly, when the user&#39;s foot applies pressure to one of the slip resistant surfaces  120  and  122 , the slip resistant surface  120  or  122  will extend biasing the spring means  130  or  132 . When the user&#39;s foot is raised for taking a step pressure is released from the slip resistant surface  120  or  122  and the spring means  130  or  132  causes the slip resistant surface  120  or  122  to retract or move forward placing it in position for the user&#39;s next step. In this way it is assured that the user will always have a slip resistant surface under their feet when walking forward. 
       FIGS. 6-9  illustrate another embodiment of the present invention. This embodiment of the invention has been adapted to a walker  210  having four wheels  224 . The four wheeled walker  210  has a frame with an attached cylinder support  216  adjacent each front wheel  224 . Cylinders  218  are attached to the cylinder support adjacent the two front wheels  224 . The cylinders  218  may be attached by other means. Cylinders  218  each contain a piston and spring. The piston is attached to a piston rod  219 . A piston rod  219  is attached to a first slip resistant surface  220  and the other piston rod  219  is attached to a second slip resistant surface  222 . That is, the first and second slip resistant surfaces  220  and  222  are attached to a respective one of the piston rods  219 . The piston rods  219  are biased by a spring so as to position the first and second slip resistant surfaces  220  and  222  underneath the frame of the walker  210 . Upon a person stepping onto one of the first or second slip resistant surfaces  220  or  222  and the walker is moved forward the piston rod  219  will be extended rearward compressing a spring within the cylinder  218 . Upon removing one&#39;s foot from either the first or second slip resistant surfaces  220  or  222  the spring bias will cause of the slip resistant surface  220  or  222  to retract under the frame of the walker  210  and to be reset in a position for a person to take another step. Therefore, one of the first or second slip resistant surfaces  220  or  222  will always be in position to be stepped upon by the person as the person walks forward with the walker  210 . The slip resistant surfaces  220  and  222  are attached to the piston rod  219  with an attachment clip or bracket  214 . The attachment clip or bracket  214  may comprise a pivot so that the slip resistant surfaces  220  and  222  may be rotated vertically 90° to be positioned out of the way when not intended to be used. 
       FIG. 7  is a plan view schematically illustrating the operation of this embodiment of the present invention. Adjacent the front wheels  224  of the walker  210  are cylinder supports  216 . The cylinders  218  contain a piston  221  and a coil or helical spring  223  placed around the piston rod  212 . The spring  223  is trapped between the piston  221  and the end of the cylinder  218  from which the piston rod  219  extends. Accordingly, when the slip resistant surface  222  is stepped on and held in position by the friction between the ground and the slip resistant surface  222  and with the walker  210  moving forward the piston rod  219  extends compressing the spring  223 . Upon stepping off of the slip resistant surface  222  the slip resistant surface will move forward closer to the front wheels  224  as the spring  223  forces the piston  221  to retract further within the cylinder  218 . 
     Slip resistant surface  220  is in a retracted position under the walker  210  with the spring  223  biasing the piston  221  close to the front wheel  224  and in a position ready to be stepped upon once again prior to advancing the walker  210  forward. Accordingly, this function assures that a slip resistant surface  220  or  222  is always in position under a person&#39;s foot as they walk advancing the walker  210  forward. This assures that a person always has secure footing even under slippery conditions, such as on ice, snow, or wet surfaces. The slip resistant surfaces  220  and  222  preferably have cleats  234  placed within keyhole openings  236 . The cleats  234  provide a sure grip on icy, snowy, or wet surfaces. 
       FIGS. 8 and 9  more clearly illustrate the cleats  234  attached to a slip resistant surface  220 . As illustrated in  FIG. 9 , the cleat  234  comprises a cleat head  242 , cleat body  244 , cleat base  246  with attached cleat spikes  248 . The cleat head  242  or cleat base  246  may be placed in and through the circular portion  238  of a cleat opening keyhole  236 . The cleat  234  is then slid sideways or longitudinally so that the cleat body  244  fits within the slot portion  240  of the cleat opening keyhole  236 . The slot portion  240  may form a friction fit with the cleat body  244  to securely hold the cleats  234  in position. This structure permits the cleats  234  to be easily removable and replaced should the spikes  248  be damaged. 
       FIGS. 10A-C  illustrate a preferred embodiment of the present invention in different positions.  FIG. 10A-C  illustrates the preferred embodiment of the present invention in an open position, a partially folded position, and a partially closed position. 
       FIG. 10A  illustrates the present invention in an open and unfolded operating position ready for use. The slip resistant retractable surface attachment  312  is attached to a walker  310 . The walker  310  may have handles  350  and a seat  352 . Attachment hooks  314  or other means for attaching are attached to a hook support bar  318  attached to legs  316  of the walker  310 . Vertical attachment bars  354  extend from the hooks  314  downward to in upper support bar  326  and a lower support bar  358 . The vertical attachment bars are perpendicular to the upper and lower support bars  326  and  358 . Attached to the vertical attachment bars  354  are side hinges  366 . Attached to the upper and lower support bars  326  and  350  are support boxes  356 . A first retractable cord spring  330  is attached to one of the support boxes  356  and a second retractable cord spring  332  is attached to the other support box  356 . The retractable cord springs  330  and  332  may be any spring capable of biasing or pulling towards the walker  310 , such as a coiled spring. Wound within each of the retractable cord springs  330  and  332  are retractable cords  360 . The retractable cord springs  330  and  332  bias the retractable cords  360  inward so that they are normally wound or coiled. Each of the retractable cord springs  330  and  332  has a loop  362  on the distal end. The loops  362  are adapted to selectively connect and disconnect from catches  364 . The catches  364  are attached to respective slip resistant surfaces  320  and  322 . The slip resistant surfaces  320  and  322  are connected to slides  370  by surface hinges  378 . The slides  370  have inner channels  374  connected to the surface hinges  378  and outer channels  372  attached to sides  368 . Slide wheels  376  or place between the outer channels  372  and the inner channels  374  so that the inner channels  374  and the outer channels  372  easily move relative to one another. This permits the slip resistant surfaces  320  and  322  to move back and forth relative to the sides  368  and against the bias of the retractable cords  360 . Each of the slip resistant surfaces  320  and  322  has removable and replaceable cleats  334  placed therein. The cleats  334  have a button top surface and a spike on the bottom extending through the slip resistant surfaces  320  and  322 . The cleats may be of a structure as illustrated in  FIGS. 8 and 9 . A textured surface or non-slip carpet  328 , only a portion of which is illustrated in  FIG. 10A  on slip resistant surface  320 , may be placed on the slip resistant surfaces  320  and  322  to provide additional comfort and traction when a foot is placed thereon. Each of the slip resistant surfaces  320  and  322  may have an opening or hole  380  therein to facilitate lifting of the respective slip resistant surfaces  320  and  322 . A handle with a hook, not illustrated, may be provided or attached to the walker  310  or the slip resistant retractable surface attachment  312  to facilitate lifting of the slip resistant surfaces  320  and  322  without having to bend over. 
       FIG. 10B  illustrates the present invention in a partially folded position. The surface hinge  378  permits the slip resistant surface  320  to be folded up adjacent the side  368 . The other side slip resistant surface  322  may also be folded upward as illustrated by the arrow. The spikes on the cleats  334  are more clearly illustrated on the bottom surface of the folded up slip resistant surface  320 . The cleats  334  may be any commercially available cleat  334  and are easily replaceable. The cleat may also be of a structure and attached to the slip resistant surfaces  320  and  322  as illustrated in  FIGS. 8-9 . 
       FIG. 10C  illustrates the present invention in a partially closed position. Once the slip resistant surfaces  320  and  322  are folded upward against the respective sides  368  the slip resistant surfaces  320  and  322  and the sides  368  may be closed about respective side hinges  366  so that the slip resistant retractable surface attachment  312  is folded and closed so as to be out of the way. The slip resistant retractable surface attachment  312  can then be conveniently stored on the walker  310  in a folded and closed position and retracted in a compact location that does not extend beyond the wheels  324 . The slip resistant retractable surface attachment  312  may also be lift in the folded and closed position or removed if not intended to be used. 
       FIGS. 10  B-C illustrate how the slip resistant retractable surface attachment  312  can be conveniently folded and closed for storage. When not needed, the loop  362  is unhooked from the catch  364  permitting the slip resistant surfaces  320  and  322  to be folded upward. After the slip resistant surfaces  320  and  322  are folded upward the sides  368  are closed inward. The structure of the embodiment illustrated in  FIGS. 10A-C  permit the slip resistant retractable surface attachment  312  to be left in position on the walker  310  until needed or removed from the walker  312  and stored. 
     The operation of the present invention is readily appreciated from  FIGS. 10A-C . The slip resistant retractable surface attachment  312  illustrated in  FIG. 10A  is in a position ready for use. The slip resistant surfaces  320  and  322  are folded down in position with the retractable cords  360  attached to the catches  364  by loops  362 . As the walker  310  is moved forward the slip resistant surfaces  320  and  322  are permitted to move back and forth longitudinally along slide  370 . When a foot is placed on one of the slip resistant surfaces  320  or  322  the pressure from a foot will hold a respective one of the slip resistant surfaces  320  and  322  in position while the walker  310  is advanced forward. The retractable cord  360  will be pulled out against the bias of the respective retractable cord springs  330  or  332 . Upon the lifting of a foot to step forward the pressure on the respective slip resistant surface  320  and  322  is removed permitting the bias force from the retractable cord springs  330  or  332  to pull the respective slip resistant surfaces  320  or  322  forward so as to place it in position for another step. In this way, as the walker  310  is advanced by the user there is always a slip resistant surface  320  or  322  in position to receive the placement of a user&#39;s foot. The longitudinal length of the slip resistant surfaces  320  and  322  in combination with the range of motion of the slides  370  should be sufficient so as to accommodate a person&#39;s gate or stride so as to assure that each respective slip resistant surface  320  and  322  are in position during the user&#39;s natural gate, pace, or stride. 
       FIGS. 11A-F  clearly illustrate the operation of the present invention as a user steps on a respective slip resistant surface  320  or  322 . In  FIG. 11A  a user places their left foot on the slip resistant surface  320  and a right foot on the slip resistant surface  322 . The foot image  320 A represents pressure applied by the left foot and the foot image  322 A represents pressure applied by the right foot. In  FIG. 11A  a user places their foot pressure on the slip resistant surface  320  and  322  while it is in a retracted position adjacent to the walker  310 .  FIG. 11B  illustrates advancing the walker  310  forward so as to extend the retractable cords  360 .  FIG. 11C  illustrates the removal of a user&#39;s left foot from the slip resistant surface  320  permitting the bias of the retractable cord  362  to move the slip resistant surface  320  towards and adjacent the walker  310 .  FIG. 11D  illustrates the advancing and positioning of a user&#39;s left foot on the newly positioned slip resistant surface  320  in the taking of a step.  FIG. 11E  illustrates a use removing their right foot from the slip resistant surface  322  causing the slip resistant surface  322  to move towards and adjacent the walker  310 .  FIG. 11F  illustrates a user moving their right foot into position onto slip resistant surface  322  in the takin of a step. This movement or stepping of the user is repeated as the walker  310  is moved forward. Accordingly, the present invention assures that a slip resistant surface  320  or  322  is positioned under a user&#39;s foot as the user advances the walker and steps forward. Therefore, the user is assured that they have secure footing when navigating slippery surfaces, such as water, snow, or ice. 
     The present invention therefore provides a means whereby any walker can be adapted to accommodate a slip resistant retractable surface attachment  312  that is easily and conveniently attached and removed. In slippery conditions, when needed the slip resistant retractable surface attachment  312  can be attached so as to provide a slip resistant surface  320  or  322  always in position under a person&#39;s foot providing secure footing. This provides substantial additional safety, particularly for an elderly person who may have compromised balance or strength. 
       FIGS. 12A to 19  illustrate another embodiment of the invention. In this embodiment of the present invention a universal or modular type attachment bracket and retractable slip resistant surface and cleat assembly is utilized for providing a retractable slip resistant surface on a variety of different types of mobility aids. The attachment bracket may be modified to attach to different types of mobility aids, such as walkers, wheeled walker&#39;s or rollators, and wheelchairs. 
       FIGS. 12A-B  illustrate two different styles of attachment brackets.  FIG. 12A  illustrates attachment brackets  414 A that are mounted on the inside of opposing legs  416  of a mobility aid  410 , such as a rolling walker. The mobility aid  410  has wheels  424  on legs  416  and a strut  482  that is pivoted by pivot  484  so that the walking aid  410  can be folded or collapsed for easy storage. The attachment brackets  414 A have two sections  454 A separated by an intermediate pivot  466 A. The pivot  466 A is placed in line with and below the pivot  484  permitting the attachment brackets  414 A of the mobility aid  410  to be folded or collapsed without removing the attachment brackets  414 A. For most wheelchairs the pivot  466 A would not be needed. Wheelchairs fold with the sides coming together eliminating the need for the attachment bracket to fold. The attachment brackets  414 A are attached to opposing legs  416  and preferably positioned as far apart as possible. 
       FIG. 12B  illustrates attachment brackets  414 B that are mounted on the outside of the legs  416  of the mobility aid  410  so as to permit the attachment brackets  414 B to be spaced apart as far as possible providing adequate room therebetween to mounted retracting slip resistant surface and cleat assemblies, not illustrated. The attachment brackets  414 B have two sections  454 B separated by an intermediate pivot  466 B. 
       FIG. 13  schematically illustrates a plan view of the present invention providing a modular universal system for easily mounting a retracting slip resistant surface and cleat assembly  412  on a walking aid  414 . The system of the present invention comprises attachment brackets  414 A attached to the mobility aid  410  and a retracting slip resistant surface and cleat assembly  412 . The retracting slip resistant surface and cleat assembly  412  comprises a slide assembly  470  and a pad and cleat head assembly  422 . The pad and cleat head assembly comprises a cleat head  486  and a pad  428 , which preferably has a slip resistant surface. 
     The slide assembly  470  has an outer slide cover  472  containing an inner slide  473 . Attached to the inner slide  473  by connector  488  is the cleat head  486  which is connected to the pad  428 . Also connected to the cleat head  486  is a retractable cord  460 . Another end of the retractable cord  460  is connected to retracting unit  430 . The retracting unit  430  is connected to the slide assembly  470  by a connector  456 . The retracting unit  430  biases or retracts the retractable cord  460  to move the pad and cleat head assembly  422  back and forth as desired. The retracting unit  430  may be any mechanical or electric device, such as a spring, elastic member, or motor. If a spring, it may be a tension, volute, coil or helical, or torsion spring. 
     The attachment brackets  414 A attached to the legs  416  of the mobility aid  410  have a channel  455  longitudinally extending therein. On one end of the channel  455  is a channel stop  457 . On the other end of the channel  455  is a channel lock  459 . The outer slide cover  472  slides onto the attachment bracket  414 A and is locked in position with the channel lock  459 . 
     In the system of this embodiment of the present invention the retracting slip resistant surface and cleat assembly  412  can be easily slid onto and slid off of the attachment bracket  414 A attached to the mobility aid  410 . By using different attachment brackets  414 A configurations adapted to be attached to different mobility aids  410  a standard, modular, or universal retracting slip resistant surface and cleat assembly  412  may be used. The retracting slip resistant surface and cleat assembly  412  can then be attached to different attachment brackets  414 A adapted to be attached to different mobility aids  410 . The retracting slip resistant surface and cleat assembly  412  may also be conveniently and easily removed from the attachment bracket  414 A when not in use or as desired. This greatly simplifies and adds flexibility to the application and use of the present invention. 
       FIG. 14  is a cross section taken along line  14 - 14  in  FIG. 13  and more clearly illustrates the structure of the attachment bracket  454 A.  FIG. 14  also more clearly illustrates the channel  455 . 
       FIG. 15  is a cross section taken along line  15 - 15  in  FIG. 13  and more clearly illustrates the structure of the slide assembly  470 . The slide assembly  470  has an outer slide cover  472  with a slide cavity  492  and a channel key  490 . The channel key  490  is adapted to mate with channel  455 , illustrated in  FIG. 14 . Placed within the slide cavity  492  is an intermediate slide  474  and an inner slide  473 . The inner slide  473  and the intermediate slide  474  and the outer slide cover  472  freely slide within each other and can be nested and extended, similar to a sliding drawer, so as to extend and retract. Rollers or bearings may be used to facilitate the sliding of the different members relative to each other. 
       FIG. 16  schematically illustrates the operation of one side of the retracting slip resistant surface and cleat assembly  412  comprising the pad and cleat head assembly  422  and the slide assembly  470 . The slide assembly  470  may be extended and retracted by relative movement of the outer slide cover  472 , the intermediate slide  474 , and the inner slide  473 . This permits the pad and cleat head assembly  422  to be moved toward and away from the retracting unit  430 . The retracting unit  430  biases the pad and cleat head assembly  422  towards the retracting unit  430  due to the attachment of the retractable cord  460 . The slide assembly  470  positions and helps to stabilize the pad and cleat head assembly  422 . Accordingly, the pad and cleat head assembly  422  is moved backward and forward to be positioned under a user&#39;s feet as the user moves forward. 
       FIG. 17-19  schematically illustrates in more detail different embodiments of a pad and cleat head assembly of the present invention.  FIG. 17  schematically illustrates a pad and cleat head assembly  422  placed adjacent the ground  423 . The pad  428  is coupled to a cleat head  486  by link  497 . The cleat head  486  pivots on pivot  495  and rides on the ground with curved contact surface  496 . On an angled surface of the cleat head  486  are placed a plurality of cleats  434 . The cleats  434  may be replaceable and attached to the cleat head  486  by any conventional attachment mechanism, such as threads, slots, releasable adhesive, screws or other equivalent means. In operation, when foot  421  of a user applies pressure to the pad  428 , the link attached to the angled portion of the cleat head  486  causes the cleat head  486  to rotate downward resulting in the cleats  434  securely engaging or embedding in the ground  423  so as to securely hold the pad  428  in place so as to provide secure footing to the user. Upon the user raising their foot  421  so as to move forward the bias from the retractable cord  460  attached to the cleat body  494  causes the cleat body  494  to rotate disengaging the cleats  434  from the ground  423  permitting the pad and cleat head assembly  422  to slide forward. Accordingly, due to the rotating cleat body  494  of the cleat head  486  the cleats  434  are selectively engaging and disengaging cleats. 
       FIG. 18  schematically illustrates another embodiment of a pad and cleat head assembly  522 . A pad  528  is coupled to a cleat head  586  by a link  597  pivotally attached to the pad  528 . A cleat body  594  has a pin  595  placed within a slot  599  guiding the rotation of the cleat body  594 . The cleat body  594  has a curved contact surface  596  contacting the ground  423  when rotated. Upon pressure being applied to the pad  528  by the user&#39;s foot the cleat body  594  is rotated causing the cleats  534  held on a curved surface of the cleat body  594  to be move downward into engagement with the ground  423 . Upon the user raising their foot releasing pressure from the pad  528  the bias from a retractable cord, not illustrated, causes the cleat body  594  to rotate disengaging the cleats  534  from the ground  423  permitting the pad and cleat head assembly  522  to move forward. A cleat head housing  501  may be placed around the cleat head  586 . 
       FIG. 19  schematically illustrates another embodiment of a pad and cleat head assembly  622 . In this embodiment the pad  628  is directly attached to a plurality of cleats  634  extending through holes  605  within a cleat head housing  601 . The cleats  634  are biased upward away from holes  605  by springs  603 . When the user&#39;s foot applies pressure to the pad  628  the cleats  634  are forced downward into the ground  423 . When the user raises their foot the springs  603  bias the pad  628  and attached cleats  634  upward disengaging the cleats  634  from the ground. This permits the bias from the retractable cord, not illustrated, to move the pad and cleat head assembly  622  forward into another position. 
     This embodiment of the present invention permits the invention to be used with a variety of mobility aids. Once an attachment bracket is fitted and attached to a mobility aid a standard or modular retracting slip resistant surface and cleat assembly can be easily attached for use and removed for transportation or storage. 
       FIGS. 20 to 23  illustrate another embodiment of the present invention. In this embodiment of the present invention a retractable slip resistant surface attachment for a mobility aid has a slip resistant surface positioning adjustment. In this embedment the slip resistant surface may be adjusted towards or away from the mobility aid depending upon the stride of the user. 
       FIG. 20  is a perspective view of the retractable slip resistant surface attachment  712  attached to the mobility aid  710 . The mobility aid  710  has a frame  717  with attached handles  718  and legs  716 . Wheels  724  are attached to legs  716  with an axle  723 . Two of the wheels  724  are attached to the front by a wheel swivel  725 . The wheel swivel  725  permits the front wheels to rotate three hundred and sixty degrees providing easy mobility and turning. A seat  752  may be placed between the frames  717 . Storage  751 , shown in phantom or dashed lines, may be positioned under the seat  752 . 
     The retractable slip resistant surface attachments  712  are removably attached to the legs  716  by attachment means  766  when in use. The attachment panels  714  of the retractable slip resistant surface attachments  712  are attached to the legs  716  by the attachment means  716 . A sliding channel bracket  754  is slidable placed in channel bracket slots  755  formed in the attachment panels  714 . This permits the sliding channel bracket  754  to be positioned longitudinally at any location along the channel bracket slots  755 . The channel bracket slots  755  may be T-shaped and mate with a complementary T-shaped leg on the sliding channel bracket  754  so as to be held onto the attachment panels  714  and yet permit longitudinal sliding there along. The leg of the channel bracket has a plurality of holes  758  therein spaced along its longitudinal length. There is at least one through hole  756  in the attachment panels  714  that is positioned to correspond or match to the plurality of holes  758  so that when the sliding channel bracket  754  is moved longitudinally within the channel bracket slots  755  a selected one of the plurality of holes  758  will align with the through hole  756 . A pin  757  is placed through the through hole and into the selected one of the plurality of holes  758  so that the sliding channel bracket  754  is held in position preventing longitudinal movement. 
     A slide panel  742  having a plurality of slide wheels  776  attached thereto is connected to a slip resistant surface  720  by hinge  778 . The plurality of slide wheels or members  776  are held within sliding channel bracket  754  and are free to move back and forth longitudinally therein. Arrow  780  illustrated the longitudinal back and forth movement of the slip resistant surface when in position for use. When not in use the retractable slip resistant surface attachments  712  may be removed from attachment means  766 , and folded with hinge  778  and stored on storage catch  766 C. 
       FIG. 21  is a rear elevation view of the present invention attached to the legs  716  of a mobility aid in position for use. The attachment means  766  may be comprised of a catch  766 A and a corresponding hook  766 B. A retraction mechanism  730 , such as a spring or elastic member, is connected to the slip resistant surface  720 . The retraction mechanism  730  permits the slip resistant surface  720  to be pulled forward towards the retraction mechanism  730  when a user removes foot pressure on the slip resistant surface  720  and to remain stationary when the user applies foot pressure on the slip resistant surface  720  and pushes the mobility aid forward. This assures that the user always has a slip resistant secure footing when walking behind the mobility aid. 
     The plurality of slide wheels  776  are held within the sliding channel bracket  754 . An axle  755  is attached to each of the plurality of slide wheels  776  and the slide panel  742 . A stop may be placed at either end of the sliding channel bracket  754  to prevent the plurality of slide wheels  776  from coming out of the ends of the sliding channel bracket  754 . The slip resistant surface  720  and the attached slide panel  742  are therefore free to move together back and forth or towards and away from the mobility aid as the user walks behind and advances the mobility aid. 
     In  FIG. 21 , the leg of the sliding channel bracket  754  is illustrated in the channel bracket slot  755 . Pin  757  is placed through the hole  756  placed in the attachment panel  714  and into the upper leg of the sliding channel bracket  754  to lock the sliding channel bracket  754  into a desired position that is comfortable or appropriate for the user. This permits the slip resistant surfaces  720  to have a range of motion that is moved closer to or further away from the mobility aid so as to accommodate the user&#39;s particular stride or movement. Arrow  784  illustrates the movement or folding of the slip resistant surface  720  so that the retractable slip resistant surface attachment  712  may be removed and conveniently stored. 
       FIG. 22  is a plan view of the present invention attached to the legs  716  of a mobility aid in position for use.  FIG. 22  more clearly illustrates the attachment and operation of the retraction mechanism  730 . The retraction mechanisms  730  are attached to a respective one of the attachment panels  714  by hinge  779 . The retractable cord  760  is attached to the retraction mechanism  730  and the slip resistant surface  720 . The retraction mechanism  730 , being attached to the attachment panel  714 , remains stationary relative to the slip resistant surface  720 . Therefore, as the slip resistant surface  720  is stepped on by the user and the mobility aid advances, the slip resistant surface  720  moves rearward away from the retraction mechanism  730  and the retraction cord  760  is extended under tension from the retraction mechanism  730 . The slip resistant surface  720  moves with the slide panel  742  with the attached slide wheels  776  moving within the sliding channel bracket  754 . Arrow  786  illustrates the movement of the sliding wheels  776  within the sliding channel bracket  754 . 
       FIG. 22  also illustrates the holes  758  placed within a leg of the sliding channel bracket  754  to receive pin  757 . Pin  757  extends through the through hole  756  in the attachment panel  714 . The pin  757  locks the sliding channel bracket into a fixed longitudinal position. The fixed longitudinal position is set to accommodate the stride or movement of the user. 
       FIG. 23  illustrates an attachment panel  714 A having a trapezoid shape. Also illustrated are the slip resistant surface  720 A, the sliding channel bracket  754 A and the hinge  778 A attaching the slip resistant surface  720 A to the attachment panel  714 A.  FIG. 23  illustrates that the attachment panel  714 A may take different shapes as necessary to attach to different mobility aids. 
     The embodiment of the present invention illustrated in  FIGS. 20-23  make possible the easy adjustment or customization of the invention to the user. The slip resistant surfaces  720  can be easily moved forward or backward so as to be positioned for easy walking or use by the user. The slip resistant surfaces  720  may be of the type having cleats as illustrated in  FIGS. 7-10C , or the type having cleat head as illustrated in  FIGS. 17-19 . The adjustable feature of the embodiment illustrated in  FIGS. 20-22  is particularly advantageous in adjusting for positioning a user&#39;s foot to contact the cleat or cleat head. This is particularly helpful when a user takes a first step forward so as to contact the cleat or cleat head in the initial first step providing secure footing. 
     Additionally, the retractable slip resistant surface attachment  712  is easily removed and stored on the side of the mobility aid  710  so as to be readily available when needed. 
     While the present invention has been described with respect to various embodiments, various modifications may be made without departing from the spirit and scope of this invention.