TECHNICAL FIELD
[0001] The present subject matter relates, in general, to armors for
protection of personnel and, in particular, to soft armor panels.
BACKGROUND
[0002] Armors are protective equipment which are worn by personnel to protect themselves from bullets, knives, and the like. A type of armors is soft armors, which protect the wearers from ballistic objects, such as bullets fired from handheld guns, and also provide reasonable flexibility for movement during combat situations. The soft armors may be manufactured in the form of panels for covering the body of the wearer.
BRIEF DESCRIPTION OF DRAWINGS
[0003] The features, aspects, and advantages of the subject matter
will be better understood with regard to the following description, and
accompanying figures. The use of the same reference number in different
figures indicates similar or identical features and components.
[0004] Fig. 1 illustrates a method of making an armor panel, in
accordance with an example implementation of the present subject matter.
[0005] Fig. 2 illustrates a mould plate used for making an armor
panel, in accordance with an example implementation of the present subject matter.
[0006] Fig. 3 illustrates an armor panel, in accordance with an
example implementation of the present subject matter.
DETAILED DESCRIPTION
[0007] The present subject matter relates to soft armor panels. Soft
armors are protective equipment that are worn by personnel for protection

against ballistic objects, such as bullets, fragments, splinters, knife and spikes. The soft armors may be manufactured in the form of panels that can cover, for example, the front and back torso, sides, neck, pelvic area, and sleeve area of a person wearing it. The panels of soft armors are commonly referred to as soft armor panels.
[0008] Typically, the soft armor panels include a plurality of layers of
high strength materials, commonly referred to as ballistic materials, stacked one on top of another. When a ballistic object//projectile, such as a bullet, hits a soft armor panel at a point of impact, the plurality of layers of the ballistic material due to its flexible nature tends to accumulate at the point of impact. The point of impact at which the plurality of layers of the ballistic material accumulate lacks the ability to absorb energy of the ballistic impact effectively. This increases the possibility of a bullet penetrating the soft armor panel and causing injury to the wearer. When the soft armor panel is subjected to multiple such ballistic objects/projectiles like bullet shots, the ballistic material layers accumulate at multiple points of impact, thereby reducing the ability of the soft armor panel to absorb energy from impacts of ballistic objects, and the safety of the wearer is compromised.
[0009] Conventionally, to prevent or to reduce the accumulation of the
ballistic material layers at the point of impact, the ballistic material layers are stitched together. Although the stitching decreases the accumulation of the ballistic layers to some extent, the holes created by the needles used for stitching significantly reduce the strength of the ballistic material layers at and close proximity of the stitched areas. Thus, the stitched areas may become weak, and therefore, may have a higher probability of being penetrated by a ballistic object.
[0010] The present subject matter relates to soft armor panels and
method of making soft armor panels. The soft armor panels are hereinafter referred to as armor panels. The armor panels of the present subject matter possess significant strength to absorb energy of impact of the

ballistic objects and prevent and/or reduce the accumulation of ballistic material layers at the points of impact. Thus, with the armor panels of the present subject matter, impact absorption capability of the armor panels may be retained even after being subjected to multiple impacts from ballistic objects.
[0011] In an example implementation of the present subject matter,
an armor panel is formed using a plurality of armor panel preforms. The armor panel preforms may be cut sheets made of ballistic materials. The armor panel preforms are stacked one on top of another between two mould plates. The two mould plates have a grid structure formed by a plurality of repeating cells. The stacked plurality of armor panel preforms is subjected to a pre-defined pressure and a pre-defined temperature for a pre-defined time duration, such that a grid-like pattern is formed on a surface of the armor panel, where the grid-like pattern corresponds to the grid structure of the mould plates. The grid-like pattern formed on the armor panel includes a plurality of compressed portions of a surface of the armor panel which forms a boundary of each of a plurality of uncompressed portions of the surface.
[0012] In the armor panels of the present subject matter, due to
presence of strong internal bonding amongst the stacked armor panel preforms at the compressed portions of the armor panel, accumulation of the ballistic material at the point of impact of a ballistic object may be prevented or reduced. Further, since the plurality of armor panel preforms is not stitched, the strength of the armor panel, which may otherwise be reduced due to the stitching, is maintained.
[0013] These and other advantages of the present subject matter
would be described in greater detail in conjunction with the following figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter.

[0014] Fig. 1 illustrates a method 100 for making an armor panel, in
accordance with an example implementation of the present subject matter. In an example implementation, the armor panel is a soft armor panel. [0015] At step 102, a ballistic sheet material is cut into several pieces for forming an armor panel. The cut pieces of ballistic sheet material may be referred to as armor panel preforms which may be compressed to form layers of the armor panel. The ballistic sheet material may be a ballistic fabric woven, unidirectional (UD), coated, laminated, or may be non-woven felts, non-woven wadding, or the like. If the ballistic fabric is woven, it is either laminated or coated with a suitable thermoplastic or thermoset film or resin. In an example implementation, the ballistic sheet material may be made of, for example, coated or laminated woven aramid, UD aramid laminates, woven ultra-high molecular weight polyethylene (UHMWPE) laminates, and UD UHMWPE laminates, and a combination thereof.
[0016] At step 104, the armor panel preforms are stacked one on top of another and are placed between two mould plates. In an example implementation, 2 to 45 armor panel preforms may be placed between the two mould plates.
[0017] The two mould plates include a top mould plate and a bottom
mould plate between which the armor panel preforms are held. Each of the two mould plates have a grid structure formed by a plurality of repeating cells. The design of a mould plate is illustrated and explained in detail with reference to Fig. 2.
[0018] As shown in Fig. 2, a mould plate 200 has a grid-like pattern having repeating cells 202-1, ..., 202-N, also referred to as repeating cells 202. The top mould plate and the bottom mould plate may have a design identical to the design of the mould plate 200. The repeating cells 202 are symmetrical in structure. Although, the repeating cells 202 in the mould plate 200 are shown to have a hexagonal shape, in an example implementation, repeating cells in a mould plate panel may have any other

geometric shape, such as circle, ellipse, rectangle, triangle, square,
pentagon, trapezoid. Further, although the edges (or boundaries) of the
repeating cells 202 are shown to be formed of straight lines, in an example
implementation, the edges (or boundaries) of the repeating cells may
formed of one of curved lines and peripheral lines. In an example
implementation, a width of the boundaries of the repeating cells 202 in the
grid structure of the mould plate may be in the range of 0.2 mm to 10 mm.
[0019] When the plurality of armor panel preforms are stacked
between two mould plates, the two mould plates are positioned such that a
boundary of each of the plurality of repeating cells 202 in one mould plate
overlaps with a boundary of a corresponding repeating cell in the other
mould plate. Thus, boundaries of the repeating cells in the top mould plate
overlay on the boundaries of corresponding repeating cells in the bottom
mould plate with the armor panel preforms stacked in between.
[0020] In an example implementation, a separator fabric sheet may
be placed between each of the mould plates and the armor panel preforms. The separator fabric sheet may be made of one of woven, unwoven, bonded, unbonded ballistic cloth. Further, in another example implementation, a breather fabric sheet may also be placed between each of the mould plates and the armor panel preforms. In an example implementation, the breather fabric sheet may be made of one of polyester. Nylon, and any other synthetic fabric material which is porous/breathable and is able to withstand the operating temperature and pressure. In an example implementation, a sequence of layers from the bottom mould plate to the top mould plate may be as follows: bottom mould plate, breather fabric sheet, separator fabric sheet, armor panel preforms, separator fabric sheet, breather fabric sheet, and top mould plate.
[0021] At step 106, the plurality of armor panel preforms stacked between the two mould plates are subjected to a pre-defined pressure and a pre-defined temperature for a pre-defined time duration. In an example

implementation, the pre-defined pressure is in a range of about 1 bar to 30 bar and the pre-defined temperature is in a range of about 80°C to 200°C. The pre-defined time duration may range from about 2 minutes to 40 minutes. In an example implementation, the mould plates, with the armor panel preforms between them, may be subjected to suction or vacuum conditions in a suction or vacuum device to press the mould plates, and in turn, compress the armor panel preforms.
[0022] Upon compression and heating of the armor panel preforms
stacked between the mould plates for the pre-defined time duration, an armor panel is formed with a grid-like pattern on its surface. The armor panel preforms are compressed to form layers of the armor panel. The grid-like pattern corresponds to the grid structure of the mould plates. The grid-like pattern formed on the armor panel includes a plurality of compressed portions which border a plurality of uncompressed portions of a surface of the armor panel. The grid-like pattern along with the compressed and uncompressed portions are illustrated later in the description through Fig. 3.
[0023] Upon completion of step 106, the armor panel is removed from
the mould plates at step 108. The armor panel may then be cut suitably for being worn by a person. In an example implementation, the armor panel may be cut in a shape of a vest, such as a bullet-proof vest. In another example implementation, in order to eliminate the cutting after step 106, the armor panel preforms may be cut suitably before being subjected to the vacuum or suction process.
[0024] Fig. 3 illustrates an armor panel 300, in accordance with an
example implementation of the present subject matter. The armor panel 300 includes a plurality of armor panel preforms stacked one on top of another and compressed to form the armor panel 300. The armor panel preforms may be made of, one of coated or laminated woven aramid, UD aramid laminates, woven UHMWPE laminates, and UD UHMWPE laminates and a combination thereof. In an example implementation, a

number of armor panel preforms in a range of 2 to 45 are compressed to form the armor panel 300. The number of armor panel preforms may be selected based on the thickness, strength, and flexibility required for the armor panel 300. In an example implementation, the thickness of the armor panel 300 is in the range of 0.15 mm to 20 mm. [0025] As shown in Fig. 3, the armor panel 300 has a grid-like pattern formed on a surface of the armor panel 300. The grid-like pattern may be formed by compression of the stacked armor panel preforms at specific portions, as described in the method 100.
[0026] The grid-like pattern corresponds to the grid structure of the
mould plates used for making the armor panel. The grid-like pattern includes a plurality of compressed portions of a surface of the armor panel. A surface of the armor panel 300 is illustrated in Fig. 3. The surface of the armor panel 300 is shown to bear a plurality of compressed portions 302. The grid-like pattern also includes a plurality of uncompressed portions 304 of the surface of the armor panel 300. The compressed portions 302 form a boundary of each of the plurality of uncompressed portions 304. In an example implementation, a width of the boundary of each of the plurality of uncompressed portions is in a range of about 0.2 mm to 10 mm.
[0027] The compressed portions 302 of the surface of the armor
panel 300 correspond to boundaries of the repeating cells in the mould plates, such as the mould plate 200 and the uncompressed portions 304 on the armor panel 300 correspond to a region bounded by the boundaries of the repeating cells in the mould plates. In an example implementation, a ratio of an area of the plurality of compressed portions 302 to an area of the plurality of uncompressed portions 304 is in a range of about 0.3 to 0.8.
[0028] As shown in Fig. 3, each of the uncompressed portions 304 are symmetrical. Although in Fig. 3, each of the uncompressed portions 304 are illustrated to have a geometric shape of a hexagon, in an example

implementation, each of the uncompressed portions 304 may have a geometric shape of a circle, an ellipse, a rectangle, a triangle, a square, a pentagon, and a trapezoid.
[0029] The compressed portions 302 of the armor panel 300 prevent
the plurality of armor panel preforms from accumulating at one point, when the armor panel 300 is subject to an impact from a ballistic object, such as a bullet. Further, the compressed portions 302 possess enhanced strength, i.e., capacity to absorb ballistic impact, compared to the uncompressed portions 304. Therefore, when the armor panel 300 is hit by a ballistic object, the delamination/shifting of the ballistic material layers due to impact of the ballistic object may be arrested by the compressed portions 302 and the impact may be localized to the uncompressed portions 304. This localized absorption of impact energy may minimize skidding of the ballistic object and thereby maintain integrity and endurance of the armor panel even if it is subjected to multiple ballistic impacts.
[0030] Further, in order to increase the strength of the armor panel
300, total area of the compressed portions 302 may be increased relative to the total area of the uncompressed portions 304 of the armor panel 300. In other words, in order to increase the strength of the armor panel 300, a ratio of the total area of the compressed portions 302 to the total area of the uncompressed portions 304 may be increased. On the other hand, to increase the flexibility of the armor panel 300, the ratio of the total area of the compressed portions 302 to the total area of the uncompressed portions 304 may be decreased.
[0031] Although the present subject matter has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the subject matter, will become apparent to persons skilled in the art upon reference to the description of the subject matter.

We Claim:
1. A method of making an armor panel, comprising:
stacking, between two mould plates, a plurality of armor panel preforms one on top of another, wherein each of the two mould plates have a grid structure formed by a plurality of repeating cells (202); and
subjecting the plurality of armor panel preforms stacked between the two mould plates to a pre-defined pressure and a pre-defined temperature for a pre-defined time duration such that a grid-like pattern is formed on a surface of the armor panel, wherein the grid-like pattern corresponds to the grid structure.
2. The method as claimed in claim 1, wherein during the stacking, the two mould plates are positioned such that a boundary of each of the plurality of repeating cells (202) in one mould plate overlaps with a boundary of a corresponding repeating cell in the other mould plate.
3. The method as claimed in claim 1, further comprising, prior to stacking, cutting the plurality of armor panel preforms from a ballistic sheet material.
4. The method as claimed in claim 3, wherein the ballistic sheet material is made of one of coated or laminated woven aramid, Unidirectional (UD) aramid laminates, woven UHMWPE laminates, and UD UHMWPE laminates, and a combination thereof.
5. The method as claimed in claim 1, wherein the pre-defined pressure is in a range of about 1 bar to 30 bar and the pre-defined temperature is in a range of about 80°C to 200°C.
6. The method as claimed in claim 1, wherein the pre-defined time
duration is in a range of about 2 minutes to 40 minutes.

7. The method as claimed in claim 1, further comprising placing a breather
fabric sheet between the plurality of armor panel preforms and each of the
mould plates.
8. The method as claimed in claim 1, further comprising placing a separator fabric sheet between the plurality of armor panel preforms and each of the mould plates.
9. An armor panel (300) comprising a plurality of armor panel preforms stacked one on top of another and compressed to form the armor panel (300), wherein the armor panel (300) has a grid-like pattern formed on a surface of the armor panel (300), the grid-like pattern comprises:
a plurality of compressed portions (302) of the surface of the armor panel (300); and
a plurality of uncompressed portions (304) of the surface of the armor panel (300), wherein the plurality of compressed portions (302) form a boundary of each of the plurality of uncompressed portions (304).
10. The armor panel (300) as claimed in claim 9, wherein a ratio of an area of the plurality of compressed portions (302) to an area of the plurality of uncompressed portions (304) is in a range of about 0.3 to 0.8.
11. The armor panel (300) as claimed in claim 9, wherein the plurality of armor panel preforms is in a range of about 2 to 45.
12. The armor panel (300) as claimed in claim 9, wherein a thickness of the armor panel is in a range of about 0.15 mm to 20 mm.

13. The armor panel (300) as claimed in claim 9, wherein a width of the boundary of each of the plurality of uncompressed portions (304) is in a range of about 0.2 mm to 10 mm.
14. The armor panel (300) as claimed in claim 9, wherein each of the plurality of uncompressed portions (304) are symmetrical and have a geometric shape of one of a hexagon, a circle, an ellipse, a rectangle, a triangle, a square, a pentagon, a trapezoid.