Abstract:
An article of footwear includes an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole includes a platform extending along a perimeter portion of the midsole and a lattice structure integrally formed with the platform, the lattice structure including a network of laths.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent document is a continuation of and claims priority from U.S. patent application Ser. No. 15/067,250, filed Mar. 11, 2016, which is a continuation of and claims priority from U.S. patent application Ser. No. 13/829,624, filed Mar. 14, 2013, the contents of which are incorporated herein by reference in their entirety. 
     
    
     FIELD 
       [0002]    This disclosure relates generally to shoes and specifically to support arrangements for shoe soles, and methods of making the same. 
       BACKGROUND 
       [0003]      FIG. 1  shows a shoe  10  to be worn on a foot of a user with a portion of the shoe  10  cut away so that the inside of the shoe  10  is partially visible. The shoe  10  includes an upper  14  and a sole  18  coupled to the upper  14 . The upper  14  covers the top and sides of the user&#39;s foot, and the sole  18  covers the bottom of the user&#39;s foot and makes contact with the ground. The sole  18  typically includes an insole  22 , a midsole  26 , and an outsole  30  which cushion and protect the user&#39;s foot while the user makes contact with the ground. The insole  22  contacts the user&#39;s foot, the outsole  30  contacts the ground, and the midsole  26  is arranged between the insole  22  and the outsole  30 . The insole  22  generally provides a comfortable surface for contact with the user&#39;s foot and is typically essentially comprised of a thin layer of a man-made material such as, for example, ethylene vinyl acetate. The midsole  26  generally provides most of the cushioning and shock absorption for the foot of the user and is typically essentially comprised of a polymer such as, for example, polyurethane, surrounding another material such as, for example, a foam, a gel, or capsules filled with air. The outsole  30  generally provides a durable surface which can sustain repeated impact and friction with the ground and is typically essentially comprised of a rubber such as, for example, carbon rubber or blown rubber. 
         [0004]    The sole  18  includes a heel end  34  arranged where a user&#39;s heel is positioned when wearing the shoe  10  and a toe end  38  arranged opposite the heel end  34  where the user&#39;s toes are positioned when wearing the shoe  10 . The sole  18  also includes a medial side  42  arranged closest to the user&#39;s center of symmetry when wearing the shoe  10  and a lateral side  46  arranged opposite the medial side  42  farther from the user&#39;s center of symmetry when wearing the shoe  10 . 
         [0005]    Turning now to  FIG. 2  and  FIG. 3 , schematic drawings of a user&#39;s foot  50  are shown including a heel  54 , toes  56 , an arch  58 , a medial side  60 , and a lateral side  62 .  FIG. 2  depicts a perspective lateral side view of the bone structure of the foot  50 , and  FIG. 3  depicts a bottom view of the foot  50  including a plurality of regions located relative to the heel  54 , toes  56 , arch  58 , medial side  60 , and lateral side  62 . A calcaneus region  66  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath a calcaneus bone  68  (shown in  FIG. 2 ) of the user, near the heel  54 . A talus region  70  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath a talus bone  72  (shown in  FIG. 2 ) of the user, between the heel  54  and the arch  58 . A longitudinal arch region  74  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath a navicular bone  76 , a cuboid bone  78  and cuneiform bones  80  (shown in  FIG. 2 ) of the user, near the arch  58 . A metatarsal region  82  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath metatarsal bones  84  (shown in  FIG. 2 ) of the user, between the arch  58  and the toes  56 . A ball of the foot region  86  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath the metatarsal-phalangeal joints  88  and sesamoids  90  (shown in  FIG. 2 ) of the user, between the arch  58  and the toes  56  and closer to the medial side  60  than the lateral side  62 . A toe region  92  (shown in  FIG. 3 ) on the bottom of the foot  50  is located substantially beneath phalangeal bones  94  (shown in  FIG. 2 ) of the user, near the toes  56 . 
         [0006]    When propelling himself on his feet, the user applies different amounts of pressure at different times to the various bones in each foot  50  during what is known as a gait cycle. For example, during a typical walking motion, the gait cycle begins when the user first contacts the ground with the heel  54  of his foot  50 , thereby applying pressure to the calcaneus bone  68 . As the user shifts his weight forward on his foot  50 , he applies less pressure to the calcaneus bone  68  and begins to apply pressure to the talus bone  72 , the navicular bone  76 , the cuboid bone  78 , and the cuneiform bones  80 . As the user begins to propel himself off his foot  50 , he applies less pressure to the talus bone  72 , the navicular bone  76 , the cuboid bone  78 , and the cuneiform bones  80  and begins to apply pressure to the metatarsal bones  84 . As the user propels himself forward, he applies pressure along the metatarsal bones  84  and to the metatarsal-phalangeal joints  88  and sesamoids  90 . Finally, as the user begins to toe off and end contact with the ground, he applies less pressure to the metatarsal-phalangeal joints  88  and sesamoids  90  and applies pressure to the phalangeal bones  94 . Finally, to toe off, the user applies pressure to the phalangeal bones  94  to propel forward. The user then lifts his foot  50  into a leg swing, and places it down in a location forward relative to where he lifted it. When the user places his foot  50  down again, he first contacts the ground with the heel  54 , beginning a new cycle of the walking motion. 
         [0007]    Many styles of forward propulsion, including many styles of walking and running, apply a gait cycle substantially similar to that described above. In some styles of forward propulsion, such as, for example, sprinting or shuffling, different amounts of pressure are applied to different portions of the foot  50  for different amounts of time. Additionally, the particular amounts of pressure applied to different portions of the foot  50  can vary from one individual to another. For example, some individuals apply more pressure to the medial side  60  than the lateral side  62  as they progress through the gait cycle. This particular application of pressure is known as pronation. In contrast, some individuals apply more pressure to the lateral side  62  than the medial side  60  as they progress through the gait cycle. This particular application of pressure is known as supination. Additionally, some individuals apply more pressure to their heels  54  when contacting the ground and some contact the ground with a portion of their feet nearer to the arch  58 . 
         [0008]    Shoes are designed to support and protect the feet of users during gait cycles to provide comfort and to promote efficient propulsion. However, due to differences between individuals in both foot anatomy and personal gait cycle style, some shoes are more comfortable and useful for some users than others. Additionally, producing a shoe configured to meet the variety of needs during all stages of the gait cycle can include producing a large number of different specialized parts which must be assembled into the shoe. Production and assembly of parts are contributing factors to the cost of the shoe. In general, a shoe having a larger number of parts is more expensive to produce than a shoe having a smaller number of parts. In view of the foregoing, it would be advantageous to provide a shoe that is comfortable and useful for a user and that is inexpensive to produce. It would also be advantageous to provide a shoe with a support arrangement that can be easily customized to meet the unique needs of various foot anatomies and individual gait styles. 
       SUMMARY 
       [0009]    In accordance with one exemplary embodiment of the disclosure, there is provided an article of footwear comprising an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole includes a platform extending along a perimeter portion of the midsole and a lattice structure integrally formed with the platform, the lattice structure including a network of laths. 
         [0010]    In accordance with another exemplary embodiment of the disclosure, there is provided an article of footwear comprising an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole comprises a lattice structure including a network of laths forming a plurality of cell units. The plurality of cell units include complete cell units and incomplete cell units. 
         [0011]    In accordance with yet another exemplary embodiment of the disclosure, there is provided an article of footwear comprising an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole includes a lattice structure including a network of laths forming a plurality of octahedron cell units. 
         [0012]    The above described features and advantages, as well as others, will become more readily apparent to those of ordinary skill in the art by reference to the following detailed description and accompanying drawings. While it would be desirable to provide an article of footwear, a midsole or a method of making an article of footwear that provides one or more of the advantageous features, the teachings disclosed herein extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the above-mentioned advantages. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a schematic drawing of a shoe as is generally known in the prior art. 
           [0014]      FIG. 2  is a schematic drawing of a medial side view of a bone structure of a foot. 
           [0015]      FIG. 3  is a schematic drawing of a bottom view of a foot. 
           [0016]      FIG. 4  is a bottom perspective view of a midsole including a platform and a lattice structure. 
           [0017]      FIG. 5  is a top view of the midsole of  FIG. 4 . 
           [0018]      FIG. 6  is a schematic drawing of a lath of the lattice structure of  FIG. 4 . 
           [0019]      FIG. 7  is a schematic drawing of a cell unit of the lattice structure of  FIG. 4 . 
           [0020]      FIG. 8  is a bottom view of the midsole of  FIG. 4 . 
           [0021]      FIG. 9A  is a schematic drawing of a first portion portions of the lattice of  FIG. 4  with partial or incomplete laths or vertices; 
           [0022]      FIG. 9B  is a schematic drawing of a second portion of the lattice of  FIG. 4  with partial or incomplete laths or vertices; 
           [0023]      FIG. 9C  is a schematic drawing of a third portion of the lattice of  FIG. 4  with partial 
           [0024]    or incomplete laths or vertices. 
           [0025]      FIG. 10  is a bottom view of the midsole of  FIG. 4  positioned within an outsole. 
           [0026]      FIG. 11  is a flowchart depicting a process for forming the midsole of  FIG. 4 . 
           [0027]      FIG. 12  is a flowchart depicting another process for forming the midsole of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    As shown in  FIG. 4 , a midsole  100  includes a platform  104  and a lattice structure or lattice  108 . The platform  104  includes a first surface  112  and a second surface  116  opposite the first surface  112 . The first surface  112  is configured to be oriented toward a bottom of the foot  50  (shown in  FIGS. 2 and 3 ) of a user when the user is wearing a shoe, such as, for example, the shoe  10  shown in  FIG. 1 , including the midsole  100 . The second surface  116  is configured to be oriented away from the bottom of the foot  50  (shown in  FIGS. 2 and 3 ) of the user when the user is wearing a shoe, such as, for example, the shoe  10  shown in  FIG. 1 , including the midsole  100 . The lattice  108  is integrally formed with the second surface  116  of the platform  104  and covers substantially all of the second surface  116  of the platform  104 . As used herein, the phrase “integrally formed with” is intended to mean formed together of the same material so as to be inseparable parts of a whole. The platform  104  and lattice  108  are essentially comprised of, for example, a polymer such as, for example, nylon. 
         [0029]    With reference to  FIG. 5 , the platform  104  also includes contours  118  formed on the first surface  112  and configured to match contours of a surface of the bottom of the foot  50  (shown in  FIGS. 2 and 3 ) of the user. The contours  118  are substantially shaped as topographic ridges formed as discreet and distinct raised levels from the first surface  112  of the platform  104 . By matching the contours  118  of the surface of the bottom of the foot  50  (shown in  FIGS. 2 and 3 ) of the user, the platform  104  is configured to receive the foot  50  (shown in  FIGS. 2 and 3 ) in a manner that feels natural to the user and that provides enhanced support and comfort to the user. 
         [0030]    The platform  104  also includes a heel end or heel portion  120 , a toe end or toe portion  124 , an arch side or medial portion  128 , and an outward side or lateral portion  132 . The platform  104  is configured such that when the midsole  100  is included in a shoe, such as, for example, the shoe  10  shown in  FIG. 1 , the heel portion  120  is positioned substantially above the heel end  34  of the sole  18  (shown in  FIG. 1 ), the toe portion  124  is positioned substantially above the toe end  38  of the sole  18  (shown in  FIG. 1 ), the medial portion  128  is positioned substantially above the medial side  42  of the sole  18  (shown in  FIG. 1 ), and the lateral portion  132  is positioned substantially above the lateral side  46  of the sole  18  (shown in  FIG. 1 ). Accordingly, when a user is wearing the shoe including the midsole  100 , the heel portion  120  is arranged to support the heel  54  of the foot  50  (shown in  FIGS. 2 and 3 ), the toe portion  124  is arranged to support the toes  56  of the foot  50  (shown in  FIGS. 2 and 3 ), the medial portion  128  is arranged to support the medial side  60  of the foot  50  (shown in  FIGS. 2 and 3 ), and the lateral portion  132  is arranged to support the lateral side  62  of the foot  50  (shown in  FIGS. 2 and 3 ). 
         [0031]    Returning now to  FIG. 4 , the lattice  108  extends generally outwardly from the second surface  116  of the platform  104 . The lattice  108  includes a plurality of laths  136 . For clarity,  FIG. 6  shows a schematic drawing of one lath  136  of the plurality of laths  136 . The lath  136  has a substantially longitudinal structure including a longitudinal axis  140 , a first end  144 , and a second end  148 . In the exemplary embodiment of  FIG. 6 , the lath  136  is substantially cylindrical in shape. The lath  136  also has a length  150  and a girth  152  that is centered about the longitudinal axis  140  and extends substantially uniformly from the first end  144  to the second end  148 . The girth  152  is a measure of circumference of the lath  136 . Because the lath is substantially cylindrically shaped, the girth  152  can be calculated with the radius R measured from the longitudinal axis  140  to the edge of the lath  136  in a direction perpendicular to the lath  136 . The girth  152  of the lath is equal to 2×π×R. In at least one exemplary embodiment, the length  150  of the lath  136  is approximately 9 millimeters. 
         [0032]    With continued reference to  FIG. 4 , the lattice  108  also includes a plurality of cell units  156 . For clarity,  FIG. 7  shows a schematic drawing of eight views of one cell unit  156  of the plurality of cell units  156 . The cell unit  156  is substantially shaped as an octahedron and is defined by eight faces  160 A- 160 H, six vertices  164 A- 164 F, and eight laths  136 A- 136 H. Each of the faces  160 A- 160 H is substantially shaped as an equilateral triangle. An octahedron has a volume determined by the length of each side. Accordingly, the volume of the cell unit  156  is determined by the length  150  of each lath. In at least one exemplary embodiment, each lath  136 A- 136 H has a length of approximately 9 millimeters such that the cell unit  156  has a volume of approximately 0.34 centimeters cubed. So that the volume of the cell unit  156  is not altered by the girth  152  (shown in  FIG. 6 ) of each lath  136 A- 136 H, the volume of the cell unit  156  is measured within the boundary defined by the longitudinal axis  140  (shown in  FIG. 6 ) of each lath  136 A- 136 H. 
         [0033]    With continued reference to  FIG. 7 , each of the six vertices  164 A- 164 F is formed by the intersection or joining together of the first end  144  or the second end  148  (shown in  FIG. 6 ) of at least two of the laths  136 A- 136 H. More specifically, vertex  164 A is formed by the intersection of an end of four laths:  136 A,  136 B,  136 C and  136 D. Vertex  164 B is formed by the intersection of an end of two laths:  136 A and  136 E. Vertex  164 C is formed by the intersection of an end of two laths:  136 B and  136 F. Vertex  164 D is formed by the intersection of an end of two laths:  136 C and  136 G. Vertex  164 E is formed by the intersection of an end of two laths:  136 D and  136 H. Finally, vertex  164 F is formed by the intersection of an end of four laths:  136 E,  136 F,  136 G and  136 H. 
         [0034]    Each of the faces  160 A- 160 H is defined by an area, bound by two laths of the laths  136 A- 136 H, within a plane defined by three adjacent vertices of the vertices  164 A- 164 F. More specifically, the face  160 A is an area, bound by laths  136 C and  136 D, within the plane defined by adjacent vertices  164 A,  164 D and  164 E. The face  160 B is an area, bound by laths  136 A and  136 C, within the plane defined by adjacent vertices  164 A,  164 B and  164 D. The face  160 C is an area, bound by laths  136 A and  136 B, within the plane defined by adjacent vertices  164 A,  164 B and  164 C. The face  160 D is an area, bound by laths  136 B and  136 D, within the plane defined by adjacent vertices  164 A,  164 C and  164 E. The face  160 E is an area, bound by laths  136 G and  136 H, within the plane defined by adjacent vertices  164 D,  164 E and  164 F. The face  160 F is an area, bound by laths  136 E and  136 G, within the plane defined by adjacent vertices  164 B,  164 D and  164 F. The face  160 G is an area, bound by laths  136 E and  136 F, within the plane defined by adjacent vertices  164 B,  164 C and  164 F. Finally, the face  160 H is an area, bound by laths  136 F and  136 H, within the plane defined by adjacent vertices  164 C,  164 E and  164 F. 
         [0035]    Returning to  FIG. 4 , the lattice  108  includes a plurality of cell units  156  arranged adjacent to one another and integrally formed with one another to construct the lattice  108  as a single unitary part. The lattice  108  forms a uniform three-dimensional pattern, and adjacent cell units  156  share laths  136  and/or vertices  164  (shown in  FIG. 7 ) such that a single lath  136  can be shared by as many as two adjacent cell units  156 , and a single vertex  164  (shown in  FIG. 7 ) can be shared by as many as six adjacent cell units  156 . Because each cell unit  156  in the pattern is substantially similar, each uniform cell unit  156  in the pattern has a substantially uniform volume. 
         [0036]    The lattice  108  extends with a height H from the second surface  116  of the platform  104 . The height H of the lattice  108  varies along the platform  104  from the heel portion  120  to the toe portion  124  and from the medial portion  128  to the lateral portion  132 . For example, as shown in  FIG. 4 , the height H 1  is different than the height H 2 . 
         [0037]    As shown in  FIG. 8 , the platform  104  is shaped to substantially match the shape of the bottom of the foot  50  (shown in  FIGS. 2 and 3 ). Accordingly, the platform  104  has an irregular perimeter  172 . Because the lattice  108  is integrally formed with and covers substantially the entirety of the second surface  116  of the platform  104 , the lattice  108  is truncated in all directions. In other words, the pattern of the lattice  108  does not extend infinitely in all three dimensions, but is limited by the height H (shown in  FIG. 4 ) and the perimeter  172  and is truncated where it is limited by the height H (shown in  FIG. 4 ) and the perimeter  172 . Accordingly, a portion of the plurality of laths  136  (shown in  FIG. 6 ), a portion of the plurality of vertices  164  (shown in  FIG. 7 ), and a portion of the plurality of cell units  156  (shown in  FIG. 7 ) in the lattice  108  are incompletely formed. 
         [0038]    For clarity,  FIGS. 9A-9C  depict schematic drawings of a number of incompletely formed parts of the lattice  108 . More specifically, as shown in  FIG. 9B , by virtue of their position relative to the height H and abutting the perimeter  172  (shown in  FIG. 8 ), partial or incomplete laths  176  have a length L that is shorter than the length  150  of the fully formed laths  136 . Similarly, as shown in  FIG. 9C , partial or incomplete vertices  180  are formed by the intersection of fewer laths  136  than the four laths  136  which intersect at fully formed vertices  164  (shown in  FIG. 7 ). Similarly, partial or incomplete cell units  184  have fewer than eight laths  136  and/or fewer than six vertices  164 . Additionally, as shown in  FIG. 9A , at least some incomplete cell units  184  are formed of incomplete laths  176  and/or incomplete vertices  180 . The incomplete laths  176 , incomplete vertices  180 , and incomplete cell units  184  are non-uniform with one another but are different as they are positioned in different locations on the lattice  108  truncated by the perimeter  172  (shown in  FIG. 8 ) and the height H (shown in  FIG. 4 ). Each incomplete cell unit  184  is defined by at least one vertex  164  or incomplete vertex  180  and at least two laths  136  or incomplete laths  176 . Accordingly, each incomplete cell unit  184  is defined by at least two partial or incomplete faces  188  defined by an area within a plane formed by at least one vertex  164  or incomplete vertex  180  and bound by at least a portion of two laths  136  or incomplete laths  176 . 
         [0039]    Returning now to  FIG. 8 , the lattice  108  includes a plurality of regions or zones formed along the midsole  100  and positioned relative to the heel portion  120 , the toe portion  124 , the medial portion  128 , and the lateral portion  132 . Specifically, the lattice  108  includes a perimeter zone  200 , a calcaneus zone  204 , a talus zone  208 , a longitudinal arch zone  212 , a metatarsal zone  216 , a ball of the foot zone  220 , and a toe zone  224 . Each zone includes complete cell units  156  (shown in  FIG. 7 ) and incomplete cell units  184  (shown in  FIGS. 9A-9C ), complete laths  136  (shown in  FIG. 6 ) and incomplete laths  176  (shown in  FIGS. 9A-9C ), and complete vertices  164  (shown in  FIG. 7 ) and incomplete vertices  180  (shown in  FIGS. 9A-9C ) that are located within that zone of the lattice  108 . In other words, the term cell unit can be used to refer to a complete cell unit and an incomplete cell unit, the term lath can be used to refer to a complete lath and an incomplete lath, the term vertex can be used to refer to a complete vertex and an incomplete vertex, and the term face can be used to refer to a complete face and an incomplete face. 
         [0040]    The perimeter zone  200  is arranged substantially along the perimeter  172  of the platform  104  and generally extends approximately 1-20 millimeters inwardly from the perimeter  172 . The calcaneus zone  204  is arranged substantially at the heel portion  120  of the platform  104  and is substantially centered between the medial portion  128  and the lateral portion  132 . The talus zone  208  is arranged nearer to the toe portion  124  of the platform  104  than the calcaneus zone  204  and is substantially centered between the medial portion  128  and the lateral portion  132 . The longitudinal arch zone  212  is arranged nearer to the toe portion  124  of the platform  104  than the talus zone  208  and is substantially spread across the medial portion  128  and the lateral portion  132 . The metatarsal zone  216  is arranged nearer to the toe portion  124  of the platform  104  than the longitudinal arch zone  212  and is substantially spread across the medial portion  128  and the lateral portion  132 . The ball of the foot zone  220  is arranged nearer to the toe portion  124  of the platform  104  than the metatarsal zone  216  and is arranged nearer to the medial portion  128  than the lateral portion  132 . The toe zone  224  is arranged nearer to the toe portion  124  of the platform  104  than the ball of the foot zone  220  and is substantially spread across the medial portion  128  and the lateral portion  132 . 
         [0041]    The lattice  108  further includes transition areas  228  arranged around and between the other zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224 . The transition areas  228  include cell units  156  and incomplete cell units  184 , laths  136  and incomplete laths  176 , and vertices  164  and incomplete vertices  180  that are not located within any other of the other zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108 . 
         [0042]    The zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  are arranged on the lattice  108  such that when the midsole  100  is included in a shoe, like the shoe  10  shown in  FIG. 1 , a user&#39;s foot  50  (shown in  FIGS. 2 and 3 ) aligns with the midsole  100  and the various zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  align to support the various regions of the user&#39;s foot  50 . More specifically, when a user wears the shoe  10  including the midsole  100 , the bottom of the foot  50  (shown in  FIGS. 2 and 3 ) is generally aligned within the perimeter zone  200 , the calcaneus region  66  (shown in  FIG. 3 ) generally aligns with the calcaneus zone  204 , the talus region  70  (shown in  FIG. 3 ) generally aligns with the talus zone  208 , the longitudinal arch region  74  (shown in  FIG. 3 ) generally aligns with the longitudinal arch zone  212 , the metatarsal region  82  (shown in  FIG. 3 ) generally aligns with the metatarsal zone  216 , the ball of the foot region  86  (shown in  FIG. 3 ) generally aligns with the ball of the foot zone  220 , and the toe region  92  (shown in  FIG. 3 ) generally aligns with the toe zone  224 . 
         [0043]    Because the user&#39;s foot  50  (shown in  FIGS. 2 and 3 ) varies in shape and structure and bears different amounts of pressure in different regions during different stages of a gait cycle, to provide support and comfort to the user throughout the gait cycle, the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108  also vary in shape and structure. Additionally, the height H (shown in  FIG. 4 ) of the lattice  108  and/or the girths  152  (shown in  FIG. 6 ) of the laths  136  and incomplete laths  176  differ between the different zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108 . The height H (shown in  FIG. 4 ) is expressible as a typical scale measurement (i.e., 4 millimeters) and is also expressible as the number of cell units  156  (shown in  FIG. 7 ) stacked on top of one another. By way of example, laths  136  (shown in  FIG. 6 ) and incomplete laths  176  (shown in  FIGS. 9A-9C ) located within the longitudinal arch zone  212  have girths  152  (shown in  FIG. 6 ) that differ from the girths  152  of laths  136  and incomplete laths  176  located within the ball of the foot zone  220 . The heights H (shown in  FIG. 4 ) and girths  152  (shown in  FIG. 6 ) of laths  136  and incomplete laths  176  within the transition area  228  are gradations between adjacent zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  to form smooth transitions of heights H (shown in  FIG. 4 ) of the lattice  108  and girths  152  (shown in  FIG. 6 ) of the laths  136  and incomplete laths  176  between the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224 . 
         [0044]    Higher heights H provide more material in the lattice  108  extending from the second surface  116  of the platform  104  which can be compressed by the foot  50  (shown in  FIGS. 2 and 3 ) as the user applies pressure during the gait cycle. Conversely, lower heights H provide less padding and position the foot  50  closer to the ground. A gradual decrease in the height H of the lattice  108  from the heel portion  120  to the toe portion  124  of the platform  104  promotes natural rolling from the heel  54  to the toes  56  of the foot  50  during gait. Thicker girths  152  provide stiffer material in the lattice  108  which is less compressible and less springy when compressed by the foot  50  (shown in  FIGS. 2 and 3 ) as the user applies pressure during the gait cycle. This is useful, for example, for providing stability and maintaining structure under the applied pressure. Conversely, thinner girths  152  provide softer material in the lattice  108  which is more compressible and springier when compressed by the foot  50  as the user applies pressure during the gait cycle. This is useful, for example, for providing spring when the user pushes off or removes pressure and for deforming to better absorb impact. Varying combinations of height H and girth  152  result in various amounts of padding, compressibility, softness, and stiffness which are appropriate for accommodating the foot  50  (shown in  FIGS. 2 and 3 ) in the different zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108  during different stages of the gait cycle. 
         [0045]    More specifically, in the perimeter zone  200 , the lattice  108  has a varying height H and laths  136  and incomplete laths  176  with relatively thick girths  152 . The height H of the lattice  108  is higher at the heel portion  120  and lower at the toe portion  124  to promote natural rolling from the heel  54  to the toes  56  of the foot  50 . The relatively thick girths  152  provide extra support to the outside of the user&#39;s foot  50  to keep the foot  50  aligned with the midsole  100 . The laths  136  and incomplete laths  176  in the perimeter zone  200  have girths  152  in a range of, for example, approximately 4.5 to 5.5 millimeters. 
         [0046]    In the calcaneus zone  204 , the lattice  108  has a relatively high height H and laths  136  and incomplete laths  176  with relatively thick girths  152  to provide substantial padding with relatively stiff cushion to the calcaneus bone  68 . This is useful to pad the calcaneus region  66  of the foot  50  when a user initially makes contact with the ground during gait because a force of the impact on the calcaneus bone  68  can be quite high during that event. The calcaneus zone  204  also should not be too soft so that the lattice  108  does not compress completely under the high force. The height H of the lattice  108  is, for example, two complete cell units  156  stacked on top of one another, or approximately 19 millimeters. 
         [0047]    In the talus zone  208 , the lattice  108  has a relatively high height H and laths  136  and incomplete laths  176  with relatively thin girths  152  to provide substantial padding with relatively soft cushion to the talus region  70  of the foot  50  during gait. The height H of the lattice  108  in the talus zone  208  is less than the height H of the lattice  108  in the calcaneus zone  204  to promote natural rolling from the heel  54  to the toes  56  of the foot  50 . The height H is still sufficiently high to provide substantial cushion near the high force. The girths  152  are thin enough to provide softer cushioning and springiness as the user pushes off the heel  54  and begins to roll the foot  50  toward the arch  58 . The laths  136  and incomplete laths  176  in the talus zone  208  have girths  152  of, for example, approximately 3 millimeters. 
         [0048]    In the longitudinal arch zone  212 , the lattice  108  has a moderate height H and laths  136  and incomplete laths  176  with relatively thick girths  152  to provide some padding with stiffer support to the longitudinal arch region  74  of the foot  50  during gait to reduce collapse of the arch  58  of the foot  50  as the user bears weight on the arch  58 . The height H of the lattice  108  in the longitudinal arch zone  212  is, for example, slightly more than one cell unit  156  or approximately 14 millimeters. The laths  136  and incomplete laths  176  in the longitudinal arch zone  212  have girths  152  in a range of, for example, approximately 4.5 to 5.5 millimeters. 
         [0049]    In the metatarsal zone  216 , the lattice  108  has a moderate height H and laths  136  and incomplete laths  176  with moderately thick girths  152  to provide some padding with some support to the metatarsal region  82  of the foot  50  during gait. The height H of the lattice  108  in the metatarsal zone  216  is, for example, slightly less than the height H of the lattice  108  in the longitudinal arch zone  212  to promote natural rolling from the heel  54  to the toes  56  of the foot  50 . The laths  136  and incomplete laths  176  in the metatarsal zone  216  have girths  152 , for example, slightly thinner than the girths  152  of the laths  136  and incomplete laths  176  in the longitudinal arch zone  212 . 
         [0050]    In the ball of the foot zone  220 , the lattice  108  has a relatively low height H and laths  136  and incomplete laths  176  with relatively thin girths  152  to provide relatively little padding with relatively soft cushion and relatively high springiness to the ball of the foot region  86  of the foot  50  during gait. The relatively low height H, compared to zones nearer to the heel portion  120  of the platform  104 , promotes natural rolling from the heel  54  to the toes  56  of the foot  50  during the stages of gait by naturally guiding the foot  50  along a downward angle from the heel portion  120  toward the toe portion  124  of the platform  104 . Additionally, the relatively low height H of the lattice  108  in the ball of the foot zone  220  provide less cushion than other zones because the ball of the foot region  86  of the foot  50  is naturally more padded than surrounding regions of the foot  50  and thus includes natural cushion to be compressed by the foot  50  during gait. The height H of the lattice  108  in the ball of the foot zone  220  is, for example, approximately 9 millimeters. The relatively thin girths  152  provide springiness as the user begins to push off the foot  50  during gait. The laths  136  and incomplete laths  176  in the ball of the foot zone  220  have girths  152  of, for example, approximately 3 millimeters. 
         [0051]    In the toe zone  224 , the lattice  108  has low height H and laths  136  and incomplete laths  176  with relatively thick girths  152  to provide little cushion and enough stiffness for the user to push off of during gait. The low height H promotes natural rolling toward the toes  56  of the foot  50  at the end of a gait cycle. The height H is sufficient to provide structure for the user to push off of at the end of a gait cycle. The height H of the lattice  108  in the toe zone  224  is in a range of, for example, approximately 3 to 5 millimeters. The relatively thick girths  152  also provide sufficient structure for the user to push off of at the end of a gait cycle. The laths  136  and incomplete laths  176  in the toe zone  224  have girths  152  of, for example, approximately 4.5 millimeters. 
         [0052]    The arrangement of laths  136  and incomplete laths  176  and cell units  156  and incomplete cell units  184  within the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108  provide a midsole  100  that is able to be included in a shoe to provide comfort and utility for a user by accommodating the foot  50  during all stages of the gait cycle. The lattice  108  enables the midsole  100  to provide mechanical cushioning by deforming along the structure of the lattice  108 , rather than just compressing, under the weight and applied pressure of the user. Further, the lattice  108  enables the midsole  100  to provide various types and amounts of cushioning to the various regions of the foot  50  due to differences in height H and girth  152  across the different zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  of the lattice  108 . Accordingly, the midsole  100  provides three-dimensional zonal compression to a user during all stages of the gait cycle. 
         [0053]    As shown in  FIG. 10 , in at least one exemplary embodiment, the midsole  100  is configured to be inserted into an outsole  300 . By forming the midsole  100  as a single, unitary piece capable of being inserted into the outsole  300 , it is possible to produce customized shoes. In the exemplary embodiment shown in  FIG. 10 , the midsole  100  fits tightly within the outsole  300  such that the lattice  108  is visible through openings  304  formed in the outsole  300 . The openings  304  provide visual access to the midsole  100  from outside the customized shoe. 
         [0054]    As mentioned above, the platform  104  and the lattice  108  are integrally formed, and the lattice  108  is formed as a single, unitary piece. Accordingly, the entire midsole  100  is formed as a single, unitary piece. As used herein, the term “single, unitary piece” is intended to mean an indivisible part that is not joined together after being formed and cannot be disassembled without destruction of the part. To form the three-dimensional structure of the midsole  100 , including the open crisscrossing structure of the lattice  108 , as a single, unitary piece must be accomplished using a highly capable manufacturing technique. More specifically, the midsole  100  is not formed using injection molding processes and the midsole  100  does not include any indications of injection molding processes, including gate marks, sprue marks, parting line marks, and ejector pin marks. In this exemplary embodiment, the midsole  100  is formed using three-dimensional printing or selective laser sintering processes. 
         [0055]    As is known in the art, three-dimensional printing and selective laser sintering processes are known as “additive processes” because they include progressively adding material to form the product. This is in contrast to manufacturing processes that start with a larger piece and progressively remove material to form the product. As shown in  FIG. 11 , the midsole  100  is formed using process  400 . To form the midsole  100  using three-dimensional printing and selective laser sintering processes, the platform  104  and the lattice  108  are printed such that the first surface  112  of the platform  104  conforms to the foot  50  of the user (step  402 ) and the lattice  108  extends from the second surface  116  of the platform (step  404 ). Printing the lattice  108  includes printing the laths  136  and the incomplete laths  176  joined together at vertices  164  and incomplete vertices  180  to form cell units  156  and incomplete cell units  184 . In at least one exemplary embodiment, the steps of the process are performed in reverse order. In at least one exemplary embodiment, the steps of the process are performed simultaneously. 
         [0056]    By forming the midsole  100  with three-dimensional printing and selective laser sintering processes it is possible to form complex three-dimensional structures including undercuts and patterns of through holes, such as the crisscrossing structure of the lattice  108 . Additionally, the lattice  108  and the platform  104  can be integrally formed of the same material in the same processing step. Because the midsole  100  is a single, unitary piece, the comfort and utility provided to the user can be accomplished with one piece instead of many. Accordingly, it is possible that the midsole  100  is less expensive to produce than a larger number of parts to be combined together to accomplish the same objective as the midsole  100 . 
         [0057]    In at least one exemplary embodiment, the midsole  100  is specifically configured to conform to a particular user&#39;s foot. As shown in  FIG. 12 , the midsole  100  of this exemplary embodiment is formed using a process  500 . More specifically, measurements of a user&#39;s foot are taken (step  502 ), including shape and size as well as force and pressure distributions along the bottom of the foot during the stages of various gait cycles. These measurements are used to prepare a pattern for a complementary lattice  108  (step  504 ) with properties of the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  and properties of the laths  136  and incomplete laths  176  and cell units  156  and incomplete cell units  184  within the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224  determined by the user&#39;s individual characteristics. By way of example, if the user applies a great amount of pressure to the heel  54  of the foot  50  during initial contact with the ground during a gait cycle, the height H of the lattice  108  in the calcaneus zone  204  is increased to provide additional cushion. Similarly, by way of example, if the user&#39;s arch  58  tends to collapse inwardly while the user applies pressure during the gait cycle, the girths  152  of the laths  136  and incomplete laths  176  in the longitudinal arch zone  212  are increased to provide additional support and reduce compression. In this way, the midsole  100  is customizable and can be configured to provide custom support to the various regions of the foot  50  through each of the zones  200 ,  204 ,  208 ,  212 ,  216 ,  220 ,  224 . Next the midsole  100  is formed using three-dimensional printing and selective laser sintering processes, the platform  104  and the lattice  108  are printed such that the first surface  112  of the platform  104  conforms to the foot  50  of the user (step  506 ) and the lattice  108  extends from the second surface  116  of the platform (step  508 ). Printing the lattice  108  includes printing the laths  136  and the incomplete laths  176  joined together at vertices  164  and incomplete vertices  180  to form cell units  156  and incomplete cell units  184 . In at least one exemplary embodiment, steps  506  and  508  of the process are performed in reverse order. In at least one exemplary embodiment, steps  506  and  508  of the process are performed simultaneously.