Abstract:
A releasable adhesive system, for securing a suction device to an attaching surface. The releasable adhesive comprises a primary material having a first portion including at least one first-portion molecule that is configured to be positioned parallel with at least one molecule of the attaching surface, and a second portion, opposite the first portion, that is configured to permanently attach to an interior surface of the suction device. The first-portion molecule positioned parallel with the molecule of the attaching surface is configured to maintain a bond between the first portion and the attaching surface up to one or more pre-determined forces on the attaching surface, such as a pre-determined shear force, pull force, and peel force. Also provided is method for using the suction device on the attaching surface, wherein the suction device contains the releasable adhesive.

Description:
CLAIM OF PRIORITY 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/079,351, filed Nov. 13, 2014, 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates generally to systems and method for temporarily or permanently joining two surfaces. More specifically, the present disclosure relates to systems and methods for temporarily or permanently joining two surfaces using a releasable adhesive. 
       BACKGROUND 
       [0003]    Reversible joining processes can be used to temporarily join materials or components. Suction connections are commonly used to join surfaces temporarily in material handling through the use of manual or vacuum-operated suction. 
         [0004]    Although suction connections are reversible in nature, the bond formed can be weakened by impurities on any of the relevant surfaces, which can lead to diminished bonding in the suction-based connection. For example, oil or dirt on a surface of a part being joined, to a suction cup, can substantially weaken the bond formed at the joining surfaces. Diminished bonding can be of particular issue where the part being joined is subjected to high-speed attachment to the suction connection. 
         [0005]    Additionally, some suction connections require a constant vacuum connection to maintain the temporary bond, especially where the part being joined includes surface texture or a complex geometry. However, the suction connection that uses a constant vacuum may prematurely disconnect from the part being joined in the event of a power failure, for example of the vacuum. 
       SUMMARY 
       [0006]    A need exists for a suction system reversible in nature, or releasable, after installation. The suction system adhesive would have load-carrying capabilities when attached to a surface, and be able to release quickly to disjoin from the surface upon a pre-determined amount of peel force. 
         [0007]    The present technology relates to systems including a releasable adhesive having many applications including in commercial industry, the private-sector (e.g., consumer), and manufacturing, among others. The releasable adhesive forms a reversible bond that utilizes van der Waals force to adhere to a surface. 
         [0008]    The releasable adhesive releasable adhesive comprises a primary material having a first portion including at least one first-portion molecule that is configured to be positioned parallel with at least one molecule of the attaching surface, and a second portion, opposite the first portion, that is configured to permanently attach to an interior surface of the suction device. The at least one first-portion molecule positioned parallel with the molecule of the attaching surface is configured to (a) maintain a bond between the first portion and the attaching surface up to a pre-determined shear force being exerted on the attaching surface, (b) maintain a bond between the first portion and the attaching surface up to a pull force of a pre-determined amount being exerted on the attaching surface, and/or (c) release the bond between the first portion and the first, attaching surface in response to a peel force exerted on the attaching surface above a pre-determined amount. In some embodiments, a plurality of first-molecules contact a plurality of molecules in the attaching surface during operation of the releasable adhesive system (e.g., when the suction device is engaged). 
         [0009]    In some embodiments, the primary material is shaped into a plurality of components each having the first portion configured to be positioned parallel with at least one molecule of the attaching surface and the second portion configured to permanently attach to the suction device. In some embodiments, each of the plurality of components is positioned at a location and extend in a direction outward from the location, forming a plurality of radii from the location. Each of the plurality of radii may be positioned at an angle with a preceding radius and a succeeding radius. In some embodiments the plurality of components are shaped to allow concentric positioning of each of the plurality of components with respect to one another. 
         [0010]    Also provided is method for using the suction device on the attaching surface, wherein the suction device contains the releasable adhesive. The method comprises positioning the suction device approximately near an attaching surface engaging the first portion with the attaching surface using a securing device, wherein at least a portion of the suction device is approximately flat against the attaching surface. 
         [0011]    In some embodiments, the engaging occurs by at least temporarily attaching a securing device to an exterior surface of the suction device. Air between the interior surface of the suction device and the attaching surface can be at least partially removed using the securing device. The securing device may be a vacuum. 
         [0012]    In some embodiments, the method further comprises, releasing the bond between the first portion and the attaching surface using the peel force. In some embodiments, the releasing occurs by introducing air into the inner surface of the suction device. Releasing can occur by exerting a force eon a securing device in contact with the attaching surface such that the suction device is released from the attaching surface. The securing device may be compressed air provided by a vacuum line. 
         [0013]    Other aspects of the present technology are described hereinafter. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  illustrates a side view of a removable adhesive in accordance with an embodiment of the present technology. 
           [0015]      FIG. 2  is a perspective view of an alternative embodiment of the removable adhesive of 
           [0016]      FIG. 1 . 
           [0017]      FIG. 3  is a side view of a second alternative embodiment of the removable adhesive of  FIG. 1 . 
           [0018]      FIG. 4  is a perspective view of a third alternative embodiment of the removable adhesive of  FIG. 1 . 
           [0019]      FIG. 5  illustrates a perspective view of a suction application of the removable adhesive of  FIG. 1 . 
           [0020]      FIG. 6  illustrates a process for using the releasable adhesive in the suction application of  FIG. 5 . 
           [0021]      FIG. 7  illustrates at top view of patterns of the releasable adhesive used by the suction application of  FIG. 5 . 
       
    
    
       [0022]    The figures are not necessarily to scale and some features may be exaggerated or minimized, such as to show details of particular components. In some instances, well-known components, systems, materials or methods have not been described in detail in order to avoid obscuring the present disclosure. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure. 
       DETAILED DESCRIPTION 
       [0023]    As required, detailed embodiments of the present disclosure are disclosed herein. The disclosed embodiments are merely examples that may be embodied in various and alternative forms, and combinations thereof. As used herein, for example, exemplary, and similar terms, refer expansively to embodiments that serve as an illustration, specimen, model or pattern. 
         [0024]    While the present technology is described primarily herein in connection with automobiles, the technology is not limited to automobiles. The concepts can be used in a wide variety of vehicle applications, such as in connection with aircraft, marine craft, and other vehicles, and consumer electronic components. Additionally, the concepts can be used in a variety of consumer applications, such as electronic components, clothing design (e.g., fasteners and closures), apparel gripping (e.g., work gloves and sports gloves), and signs (e.g., permanent signage for a business and temporary signage for a traffic detour), among others. Furthermore, the concepts can be used in low temperature environments (e.g., aeronautical applications in space) where conventional adhesives lose gripping. 
         [0025]    Various embodiments of the present disclosure are disclosed herein. The disclosed embodiments are merely examples that may be embodied in various and alternative forms, and combinations thereof. 
       I. Overview of the Disclosure 
       [0026]      FIG. 1  illustrates a releasable adhesive  100 , which allows reversible bonding through the use of van der Waals force. The releasable adhesive  100  adheres and releases from a first surface  10  and a second surface  20  where surface  10 ,  20  are substantially solid surfaces made of varying materials and textures of the surfaces  10 ,  20 . 
         [0027]    The releasable adhesive  100  comprises a primary material  110  that has particles (e.g., molecules, atoms, ions) generally parallel with respect to particles within the first surface  10 , the second surface  20 . As seen in the callout of  FIG. 1 , molecules  115  of the primary material  110  are parallel with molecules  25  of the second surface  20 , at a location of attachment. Van der Waals force allows the molecules  115  of the primary material  110  to adhere to the second surface  20 . Specifically, the molecules  115  of the primary material  110  maintain a bond between the releasable adhesive  100  and an attaching surface (e.g., the second surface  20 ) against pull forces  80  and shear forces  85 . 
         [0028]    Unlike a traditional chemical bonding process required by typical adhesives, the releasable adhesive  100  does not require curing, thus allowing the releasable adhesive  100  to adhere to the surfaces  10 ,  20  almost instantaneously. The releasable adhesive  100  can also adhere to the surface  10 ,  20  without use of an external power supply, actuator, or otherwise. 
         [0029]    Van der Waals force also allows the bond between the molecules  115  of the primary material  110  and the molecules of the attaching surface (e.g., the molecules  25  of the second surface  20 ) to detach when peel forces  90  are applied to the surfaces attaching surface or the releasable adhesive  100 . As seen in the callout of  FIG. 1 , where the primary material  110  is not in contact with to the second surface  20 , the molecules  115  of the primary material  110  are not generally parallel to the molecules  25  of the second surface  20 . 
         [0030]    In some embodiments, the primary material  110  includes a microstructured and/or a nanostructured polymer, such as silicone and polydimethylsiloxane (PDMS), among others. In some embodiments, the primary material  110  includes polymers such as (functionalized) polycarbonate, polyolefin (e.g., polyethylene and polypropylene), polyamide (e.g., nylons), polyacrylate, acrylonitrile butadiene styrene. 
         [0031]    In some embodiments, the primary material  110  includes composites such as reinforced plastics where the plastics may include any of the exemplary polymers listed above, and the reinforcement may include one or more of the following: clay, glass, carbon, polymer in the form of particulate, fibers (e.g., nano, short, or long fibers), platelets (e.g., nano-sized or micron-sized platelets), and whiskers, among others. 
         [0032]    The primary material  110  can include synthetic or inorganic, molecules. While use of so-called biopolymers (or, green polymers) is becoming popular in many industries, petroleum based polymers are still much more common in every-day use. The primary material  110  may also include recycled material, such as a polybutylene terephthalate (PBT) polymer, being, e.g., about eighty-five percent post-consumer polyethylene terephthalate (PET). In one embodiment, the primary material  110  includes some sort of plastic. In one embodiment, the material includes a thermoplastic. 
         [0033]    In one embodiment the primary material  110  includes a composite. For example, the primary material  110  can include a fiber-reinforced polymer (FRP) composite, such as a carbon-fiber-reinforced polymer (CFRP), or a glass-fiber-reinforced polymer (GFRP). The composite may be a fiberglass composite, for instance. In one embodiment, the FRP composite is a hybrid plastic-metal composite (e.g., plastic composite containing metal reinforcing fibers). The primary material  110  in some implementations includes a polyamide-grade polymer, which can be referred to generally as a polyamide. In one embodiment, the primary material  110  includes acrylonitrile-butadiene-styrene (ABS). In one embodiment, the primary material  110  includes a polycarbonate (PC). The primary material  110  may also comprise a type of resin. Example resins include a fiberglass reinforced polypropylene (PP) resin, a PC/PBT resin, and a PC/ABS resin. 
       II. Embodiments of the Releasable Adhesive 
       [0034]    In the embodiment shown in  FIG. 1 , the releasable adhesive  100  comprises a plurality of setae  130  (e.g., synthetic setae). Van der Waals force allows the primary material  110  within/on each setae  130  to adhere and release to the surfaces  10 ,  20  using attractions and repulsions between particles (e.g., atoms, molecules, ions) of the primary material  110  and the surfaces  10 ,  20 . 
         [0035]    As described above, van der Waals force allows the molecules  115  of the primary material  110  to attach and detach from the molecules of the attaching surface (e.g., the molecules  25  of the second surface  20 ), depending on the orientation of the molecules  115  of the primary material  110  and the molecules of the attaching surface. Specifically, the van der Waals force allows the primary material  110  within or on the setae  130  to attach to and peel away from the surfaces  10 ,  20  to reverse (release) the bond formed between the primary material  110  within/on the setae  130  and the surfaces  10 ,  20 . 
         [0036]    Impurities on or in the surfaces  10 ,  20 , such as dirt, oil, and air pockets, do not substantially weaken the overall bond formed by the releasable adhesive  100  because of the many areas of contact between the setae  130  and the surface  10 ,  20 . Specifically, the setae  130  form a plurality of independent bonds with the surface  10 ,  20 , which allows the releasable adhesive  100  to bond even with the existence of some impurities affecting the bond at one or more limited points of interface. 
         [0037]    The releasable adhesive  100 , including each setae  130 , may be designed to have a pre-determined of load-bearing capability. For example, where a load to be bore is from a small object under tension loading, the load bearing capability of the releasable adhesive  100  may be between about 0.05 kilograms of force per square centimeter (kg/cm 2 ) and about 1.0 kg/cm 2 , wherein the area measurement (cm 2 ) is the surface area of the primary material  110  within/on each setae  130 . However, where the object is under shear loading, the load bearing capability of the releasable adhesive  100  may be between about 1.0 and about 20 kg/cm 2 . 
         [0038]    In some embodiments, as also shown in  FIG. 1 , the primary material  110  is infused with an embedded material  120 . In some embodiments, the embedded material  120  is a material being similar in composition (e.g., material composition or chemical composition) to the primary material  110 . In other embodiments, the embedded material  120  is a material different than the primary material  110 . 
         [0039]    The embedded material  120  can include particles or pathways infused into a molecular structure of the primary material  110 . The embedded material  120  may be infused into each of the setae  130  within the primary material  110 . Alternatively, the embedded material  120  may be infused into selected setae  130 , shown in  FIG. 1 . 
         [0040]    In some embodiments, the embedded material  120  is selected to reinforce strength of the primary material. Reinforcing strength of the primary material allows the primary material to sustain against greater shear forces and pull forces. 
         [0041]    In some embodiments, the embedded material  120  may be used to increase electrical and/or thermal conductivity of the primary material  110 . For example, doping (e.g., vary placement any numbering of electrons and holes within a molecular structure) can be used to increase conductivity of the primary material  110 . Increasing conductivity of the primary material, and thus releasable adhesive  100 , may be important in applications where the surfaces  10 ,  20  need to conduct electricity. For example, doping of the primary material  110  may be suitable in an application where the releasable adhesive  100  serves as a conductor within a battery application. 
         [0042]    The embedded material  120  can include a conductive fillers such as, but not limited to, carbon nanotubes, carbon black, metal nanoparticles (e.g., copper, silver, and gold), or combination thereof. 
         [0043]    In another embodiment, seen in  FIG. 2 , the setae  130  are formed into an array of truncated prisms  132 . Each truncated prism includes at least one side  134  and at top  136  (seen in the callout of  FIG. 1 ), which serve as flat, generally flat, or smooth surfaces to maximize contact with an attaching surface (e.g., the first surface  10 ). The van der Waals force that can be exerted on the attaching surface is higher with greater contact area, and so maximizing contact with the attaching surface is a priority in design of the adhesive  100 . 
         [0044]    In some embodiments the truncated prisms can vary in geometric shape. For example, as seen in  FIG. 2 , the array of truncated prisms can be formed in the shape of a truncated pyramid, where each pyramid includes two sides  134  and top  136  that are used to generate sufficient van der Waals force for adhesion with the surfaces  10 ,  20 . However, the array of truncated prisms can be in the form of a truncated cone (e.g., sloping or frustro-conical surface), where the side  134  extends around a circumference of a circular base. 
         [0045]    Impurities on or in the surfaces  10 ,  20 , such as dirt, oil, and air pockets, do not lead to a substantial weaken the overall bond because of the many areas of contact between the truncated prisms  132  and the surface  10 ,  20 . Specifically, the truncated prisms  132  form a plurality of independent bonds with the surface  10 ,  20 , which allows the releasable adhesive  100  to bond even with the existence of some impurities affecting the bond at one or more limited points of interface. 
         [0046]    The array of truncated prisms  132  are extended across a defined width  140 . The width  140  can range approximately between 1 millimeter (mm) and 20 mm. The truncated prisms repeat along a defined length  142  with a range similar to the width  140 . Spacing between each prism  132  should be sufficient to allow contact to a surface (e.g., the first surface  10 ). For example, a space  138  between one edges of a first prism  132  and a subsequent prism  132  may be between 10 nanometers (nm) and 200 micrometers (μm—). 
         [0047]    In some embodiments, the truncated prisms  132  may include the embedded material  120 . The embedded material  120  may be added (e.g., doped) into the microstructure of truncated prisms  132 . 
         [0048]    In another embodiment, seen in  FIG. 3  the releasable adhesive  100  may include a plurality of layers including an adhesion pad  150 , a skin  160 , and a tendon  170 . Collectively, the plurality of layers maximize areas of contact with the surfaces  10 ,  20  while maintaining stiffness a direction of applied loads (e.g., along the fibers of the fabric of the skin  160 ). 
         [0049]    In this embodiment, the adhesion pad  150  (e.g., a polymer elastomer) attaches to the skin  160  (e.g., woven fabric) which is attached to a tendon (e.g., woven fabric). Attaching the adhesion pad  150  to the skin  160  and the tendon  170  provides strength enabling adhesion to maintain against shear force  85  and pull force  80 . An example in  FIG. 3  illustrates how the first surface  10  is maintained against shear forces  85  and pull forces  80  through stiffness of fabric (e.g., fibers) within the releasable adhesive  100 . 
         [0050]    Additionally, the plurality of layers provide stiffness in a direction of peel loading (e.g., peel force  90 ), thus enabling release from the attached surface (e.g., the second surface  20  as seen in  FIG. 3 ). 
         [0051]    The adhesion pad  150  may include materials that behave elastically within a pre-determined force capacity range of a desired application. The materials should ensure deformation losses (e.g., viscoelastie, plastic, or fracture) in the materials of the adhesion pad  150  are minimized or otherwise reduced. The adhesion pad  150  may include materials such as, but not limited to, silicone, PDMS, and the like. The adhesion pad  150  may have a thickness between 10 nm and 100 nm. 
         [0052]    The skin  160  may include similar elastic materials that minimize deformation losses as described in association with the adhesion pad  150 . The skin  160  may include woven fabric materials such as carbon fiber fabric, fiber glass, KEVLAR® (KEVLAR is a registered trademark of E. I. du Pont de Nemours and Company of Wilmington, Del.), and the like. The skin  160  may have a thickness between 10 nm and 1 mm. 
         [0053]    The tendon  170  may include woven fabric materials with high stiffness fibers such as glass fiber, nylon, and carbon-fiber, among others. The tendon  170  should be of a thickness that sufficient attaches the pad  150  to the skin  160 . For example, the tendon  170  can have a length between 1 mm and 100 mm. 
         [0054]    The connection between the tendon  170  and the adhesion pad  150  may have pre-defined dimensions, orientation, and spatial location according to particular a desired application. The pre-defined dimension can be altered to balance shear and normal loading requirements for the desired application. 
         [0055]    In electrically conductive applications, the pad  150  can be doped with the embedded material  120 . For example, the embedded material  120  can include metal nanoparticles as stated above. In some embodiments, the skin  160  and/or the tendon  170  can also be doped electrically conductive materials (e.g., carbon fiber fabric). 
         [0056]    Where the tendon  170  attaches to the pad  150  can affect functionality of the releasable adhesive  100 . Characteristics such as thickness of the tendon  170 , material composition of the tendon  170 , and positioning of tendon  170  with respect to the pad  150  can be set in various ways to achieve different results for desired performance in various applications. For example, positioning of the tendon  170  can affecting hanging ability. Attaching the tendon  170  at an edge of pad  150  allows increase strength of the releasable adhesive  100  in the shear direction, as seen in  FIG. 3 . However, attaching the tendon  170  on an inner surface of the pad  150  allows increased strength of the releasable adhesive  100  in the pull direction. 
         [0057]    In another embodiment, seen in  FIG. 4  the releasable adhesive  100  (e.g., setae  130 , the prisms  132 ) may be formed as a flexible structure that can be molded to surround or otherwise connect surfaces. For example, the releasable adhesive  100  may function similar to single-sided tape. 
         [0058]    In some embodiments, the releasable adhesive  100  can be included on one more than one surface for purposes of adhesion. For example, the releasable adhesive  100  may function as a double-sided tape. 
         [0059]    The single-sided or double-sided tape may be used to position between, pinch together, wrap around, or otherwise hold together the surfaces  10 ,  20 . 
         [0060]    The single-sided or double-sided tape may utilize the releasable adhesive  100  in a non-conductive form or with conductive doping, using the embedded material  120 . For example, the releasable adhesive  100  may be in the form of a conductive, single-sided tape, which may be used to secure the surfaces  10 ,  20  to one another and pass electrical currents through one another and the single-sided tape, as seen in  FIG. 4 . 
       III. Releasable Adhesive Application 
       [0061]      FIG. 5  illustrates use of the releasable adhesive  100  in a suction-connection application. A single-sided form of the releasable adhesive  100  may be used to bond a suction cup  200  to a surface using a securing device  210 . In suction applications, the first surface  10  is an inside surface of the suction cup  200  affixed to (e.g., using a conventional permanent adhesive) a non-adhesive side of the releasable adhesive  100 , and the second surface  20  is a contact surface of an item to which the suction cup  200  is to attach, as seen in  FIG. 5 . 
         [0062]    The releasable adhesive  100  within suction applications should be of a thickness to allow contact with the inside surface of the suction cup  200 . Additionally, the thickness of the releasable adhesive  100  should be such that the suction cup  200  may significantly flatten during engagement with the second surface  20 . For example, the thickness of the releasable adhesive  100  may be between about 100 μm and about 2.0 mm to prevent introduction of air into the suction cup  200 , which may diminish the holding of the suction cup  200 . 
         [0063]      FIG. 6  illustrates a process for positioning, engaging, and releasing the suction cup  200 , including the releasable adhesive  100 , from the second surface  20 . 
         [0064]    At step  230 , the suction cup  200  is positioned approximately near the second surface  20 . During positioning, the suction cup  200  is placed with the releasable adhesive  100  adjacent the second surface  20  (e.g., the suction cup  200  facing down). The securing device  210  can be used to push the suction cup  200  to the second surface  20  or stabilize the suction cup  200  while the second surface  20  is pushed to the suction cup  200 . For example, the securing device  210  can be a mechanical device to push the suction cup  200  to the second surface  20 . Alternatively, the securing device  210  can be a vacuum line used to remove air between the inside surface of the suction cup  200  and the second surface  20 , thus securing the suction cup  200  to the second surface  20 . 
         [0065]    At step  240 , the suction cup  200  is fully engaged with the second surface  20  (e.g., at least a portion of the suction cup  200  is flat against the second surface  20 ). During engagement, the inside surface of the suction cup  200 , which contains the releasable adhesive  100 , is fully engaged or otherwise connected to the second surface  20 . In some embodiments, the suction cup  200  may be held in connection with the second surface  20  by a device to enhance holding of the suction cup  200  (e.g., vacuum). 
         [0066]    Utilizing the releasable adhesive  100  with the suction cup  200 , may enhance holding power of vacuum grippers, for example, when the second surface  20  is subjected to high-speed attachment and placement. Specifically, the releasable adhesive  100  can hold the second surface  20  without vacuum and its restrictions to certain surface texture or geometry conditions. In some circumstances, the gripper may also be used as fail-safe in the event of power or vacuum source failure. 
         [0067]    At step  250 , the suction cup  200  is released from the second surface  20 . The suction cup  200  can be released by using the securing device  210  as a push plunger, for example, to peel the suction cup  200  from the second surface  20 . Alternatively, compressed air can be introduced into the inside surface of the suction cup  200  using the securing device  210 . When the suction cup  200  is released, the releasable adhesive  100  is separated from the second surface  20 . 
         [0068]    Additionally, the releasable adhesive  100  may form patterns within the suction cup  200  as seen in  FIG. 7 . Patterns accommodate general properties (e.g., geometry and texture) and functional properties (e.g., load capacity) of the suction cup  200 . Additionally, patterns may increase the holding force in the lateral and/or shear direction, providing resistance to the attaching surface (e.g., the second surface  20 ). Patterns may include, but are not limited to, a fill cup pattern  262 , a radial pattern  264 , a ring pattern  266 , and a grid pattern  268 . One of skill in the art would anticipate other patterns are possible depending on the application. 
         [0069]    The full cup pattern  262  may be beneficial where maximum contact of the releasable adhesive  100  is desired to the surface  20 . Creating maximum contact may be needed where the releasable adhesive  100  is intended to carry a load near a maximum material constraint of the releasable adhesive  100 . 
         [0070]    The radial pattern  264  may be beneficial where the first surface  10  inside the suction cup  200  may include radial ribs that increase the stiffness of the suction cup  200 . The radial pattern  264  is an effective way to attach the releasable adhesive  100  to the suction cup  200  and enhance its holding or bonding capability. The radial pattern  264  may also provide for a faster release of the suction cup  200  as compared to the frill cup pattern  262 , for example, due to less of the releasable adhesive  100  being employed. 
         [0071]    An angle  265  can be formed between each of the radii to adequately space the releasable adhesive  100  throughout the suction cup  200 . The angle  265  can be the same throughout the radial pattern  264 , as seen in  FIG. 7 . Alternatively, the angle  265  can vary throughout the radial pattern  264 . 
         [0072]    The ring pattern  266  may also be beneficial where the first surface  10  inside the suction cup  200  has a non-conical geometry (e.g., spherical) that requires a plurality of releasable adhesives  100  (e.g., in the form of narrow rings) to simplify attachment to the suction cup  200  and maintain the maximum contact with the first surface  10 . The number of rings can depend on factors such as the amount of release time. For example, the fewer the amount of rings, the faster the suction cup  200  can be released. 
         [0073]    Geometric shapes forming the ring pattern  266  can be concentric in nature as seen in  FIG. 6  where the concentric geometric shape of the ring pattern  266  is circular. It should be appreciated that the ring pattern  266  can be formed using a number of geometric shapes such as squares, circles, ovals, and triangles, among others. 
         [0074]    The grid pattern  268  may be beneficial where a pre-determined surface area of the suction cup  200  needs to be covered, but where the full cup pattern  262  is not necessary. The grid pattern  26   g  can provide for quick attachement of the releasable adhesive  100  to the first surface  10  of the suction cup  200 . The grid pattern  268  can be formed using a number of geometric shapes desirable for particular applications such as circles, squares, ovals, and the like. The geometric shaped forming the grid pattern can be independent in nature as seen by as seen in  FIG. 6  where the geometric shape of the grid pattern  268  is a square. 
         [0075]    In some embodiments, the releasable adhesive  100  may include a plurality of conductive suction cups  200  on an electrically conductive substrate (e.g., metal or conductive polymer). In such an application, the primary material  110  used within the suction cups  200  can include one or more electrically conductive materials as described above. 
       IV. CONCLUSION 
       [0076]    Various embodiments of the present disclosure are disclosed herein. The disclosed embodiments are merely examples that may be embodied in various and alternative forms, and combinations thereof. 
         [0077]    The above-described embodiments are merely exemplary illustrations of implementations set forth for a clear understanding of the principles of the disclosure. 
         [0078]    Variations, modifications, and combinations may be made to the above-described embodiments without departing from the scope of the claims. All such variations, modifications, and combinations are included herein by the scope of this disclosure and the following claims.