Abstract:
Embodiments relate generally to wearable electrical and electronic hardware, computer software, wired and wireless network communications, and to wearable/mobile computing devices. More specifically, various embodiments are directed to, for example, aligning a flexible substrate and/or components thereof during fabrication to enhance reliability. In one example, a method includes forming a framework that includes, for example, a portion (e.g., an anchor portion) configured to couple to a flexible substrate, the portion having a neutral axis. Also, the method may include forming a flexible substrate that includes a supported flex region including conductors and one or more rigid regions configured to receive one or more components. A rigid region might include an encapsulated rigid region. The method further may also include aligning the encapsulated rigid region at an angle to the neutral axis, and molding over the encapsulated rigid region.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/903,955 filed Nov. 13, 2013 with Attorney Docket No. ALI-346P, which is herein incorporated by reference. This application herein incorporates by reference the following applications: U.S. patent application Ser. No. 13/942,503 filed Jul. 13, 2013 with Attorney Docket No. ALI-001CIP1CIP1CON1CON1, U.S. patent application Ser. No. 14/______ filed Nov. 13, 2014 with Attorney Docket No. ALI-344 titled “FLEXIBLE SUBSTRATES FOR WEARABLE DEVICES,” U.S. patent application Ser. No. 14/______ filed Nov. 13, 2014 with Attorney Docket No. ALI-345 titled “CONDUCTIVE STRUCTURES FOR A FLEXIBLE SUBSTRATE IN A WEARABLE DEVICE,” and U.S. patent application Ser. No. 14/480,628 (ALI-516) titled “WEARABLE DEVICES INCLUDING METALIZED INTERFACES AND STRAP-INTEGRATED SENSOR ELECTRODES” filed on Sep. 8, 2014. 
     
    
     FIELD 
       [0002]    Embodiments relate generally to wearable electrical and electronic hardware, computer software, wired and wireless network communications, and to wearable/mobile computing devices. More specifically, various embodiments are directed to, for example, aligning a flexible substrate and/or components thereof for enhanced reliability. 
       BACKGROUND 
       [0003]    Conventional wearable devices, such as data capable bands or wrist bands, typically require circuit boards to be formed from flexible materials. Some approaches to fabricating wearable devices typically introduce internal stress among some of the components or elements during fabrication. Such internally-induced stresses may detrimentally affect functionality of the wearable device over time. In typical fabrication processes, misaligned orientations of components or elements during molding processes can give affect reliability by exacerbating the effects of the orientations. The above-described fabrication processes, while functional, are generally sub-optimal. 
         [0004]    Thus, what is needed is a solution for aligning at least components associated with a flexible substrate without the limitations of conventional techniques. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    Various embodiments or examples (“examples”) of the invention are disclosed in the following detailed description and the accompanying drawings: 
           [0006]      FIG. 1  illustrates an example of an alignment orientation for a component of a flexible substrate, according to some embodiments; 
           [0007]      FIG. 2  is a diagram showing a side view of an orientation of a portion of a flexible substrate, according to some embodiments; 
           [0008]      FIG. 3  is a diagram showing a side view of a flexible substrate including components coupled to a framework, according to some examples; 
           [0009]      FIG. 4  is a diagram depicting translation of a component, according to some examples; 
           [0010]      FIG. 5  is a diagram showing a side view of a flexible substrate including components translated relative to a framework, according to some examples; 
           [0011]      FIG. 6  is an example of a flow for translating a component for a flexible substrate, according to some embodiments; 
           [0012]      FIG. 7  is a diagram showing a side view of an orientation of a portion of another example of a flexible substrate, according to some embodiments; 
           [0013]      FIG. 8  depicts an example of a wearable device assembly in which an electrode bus as a flexible substrate may be coupled to circuitry in a housing, according to some embodiments; 
           [0014]      FIGS. 9A and 9B  are diagrams depicting different views of an example of an electrode bus as a flexible substrate, according to some embodiments; and 
           [0015]      FIG. 10  is a diagram showing a side view of an electrode bus including components translated relative to a portion of a framework, such as a cradle, according to some examples. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Various embodiments or examples may be implemented in numerous ways, including as a system, a process, an apparatus, a user interface, or a series of program instructions on a computer readable medium such as a computer readable storage medium or a computer network where the program instructions are sent over optical, electronic, or wireless communication links. In general, operations of disclosed processes may be performed in an arbitrary order, unless otherwise provided in the claims. 
         [0017]    A detailed description of one or more examples is provided below along with accompanying figures. The detailed description is provided in connection with such examples, but is not limited to any particular example. The scope is limited only by the claims and numerous alternatives, modifications, and equivalents are encompassed. Numerous specific details are set forth in the following description in order to provide a thorough understanding. These details are provided for the purpose of example and the described techniques may be practiced according to the claims without some or all of these specific details. For clarity, technical material that is known in the technical fields related to the examples has not been described in detail to avoid unnecessarily obscuring the description. 
         [0018]      FIG. 1  illustrates an example of an alignment orientation for a component of a flexible substrate, according to some embodiments. Diagram  100  depicts a rigid region  120  including one or more components formed in, on, or coupled to a flexible substrate  106 , which includes conductors for conveying data signals. Rigid region  120  and/or components thereof are oriented relative to a surface portion  157  of a framework  155 , which is configured to receive and couple to flexible substrate  106  and rigid region  120 . According to some examples, a median plane  122  passes through a middle region of a component  120   a  (e.g., an encapsulated component  120   a ) to substantially divide component  120   a  into a top portion and a bottom portion. 
         [0019]    In some examples, median plane  122  can be oriented relative to a surface portion  157   a  so that component  120   a , flexible substrate  106 , and framework  155  can be covered by molding material  192  from a molding tool  190 , which, in this instance, is depicted graphically as a plunger/syringe-like tool. Surface portion  157   a  can be coextensive with a line from which media plane  122  can be oriented such that medial plane  122  is substantially parallel to surface portion  157   a . According to some examples, a parallel or substantially parallel orientation can reduce or negate stresses for different sizes of framework  155  during, for example, overmolding processes to form wearable device  170 . 
         [0020]    In some examples, flexible substrate  106  may include an electrode bus, as described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which may include conductors to couple to electrodes (e.g., bioimpedance or GSR electrodes) and to logic (e.g., bioimpedance logic and circuitry or GSR logic and circuitry). Framework  152 , in some examples, may include at least interior structures of a wearable pod  182  or may include a cradle structure as described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0021]    In some examples, as depicted in diagram  100 , flexible substrate  120  and its components mounted thereupon are coupled to framework  152  to form a constituent part of a wearable device  180 . In the example shown, wearable device  180  may include a wearable pod  182  that can include logic, including processors and memory, configured to detect, among other things, physiological signals via bioimpedance signals. In one example, wearable pod  182  can include bioimpedance circuitry configured to drive bioimpedance through one electrode  186  disposed in a band or strap  181 . Strap  181  may be integrated or removable coupled to wearable pod  182 . 
         [0022]    One or more flexible substrates (not shown) may include conductive materials disposed in interior  184  of band or strap  181  to, for example, couple electrodes  186  to logic (or any other component) in wearable pod  182  or any other portion of wearable device  180 . In at least one example, electrodes  186  can be implemented to facilitate transmission of bioimpedance signals to determine physiological signals or characteristics, such as heart rate. Further, electrodes  186  may also be coupled via a flexible substrate to a galvanic skin response (“GSR”) logic circuit. 
         [0023]    A wearable pod and/or wearable device may be implemented as data-mining and/or analytic device that may be worn as a strap or band around or attached to an arm, leg, ear, ankle, or other bodily appendage or feature. In other examples, a wearable pod and/or wearable device may be carried, or attached directly or indirectly to other items, organic or inorganic, animate, or static. Note, too, that wearable pod enough be integrated into or with a strap  181  or band and can be shaped other than as shown. For example, a wearable pod circular or disk-like in shape with a display portion disposed on one of the circular surfaces. 
         [0024]    According some embodiments, logic disposed in wearable pod (or disposed anywhere in wearable device, such as in strap  181 ) may include a number of components formed in either hardware or software, or a combination thereof, to provide structure and/or functionality therein. In particular, the logic may include a touch-sensitive input/output (“I/O”) controller to detect contact with portions of a pod cover or interface, a display controller to facilitate emission of light, an activity determinator configured to determine an activity based on, for example, sensor data from one or more sensors (e.g., disposed in an interior region within wearable pod  182 , or disposed externally). A bioimpedance (“BI”) circuit may facilitate the use of bioimpedance signals to determine a physiological signal (e.g., heart rate), and a galvanic skin response (“GSR”) circuit may facilitate the use of signals representing skin conductance. A physiological (“PHY”) signal determinator may be configured to determine physiological characteristic, such as heart rate, among others, and a temperature circuit may be configured to receive temperature sensor data to facilitate determination of heat flux or temperature. A physiological (“PHY”) condition determinator may be configured to implement heat flux or temperature, or other sensor data, to derive values representative of a condition (e.g., a biological condition, such as caloric energy expended or other calorimetry-related determinations). Logic can include a variety of other sensors and other logic, processors, and/or memory including one or more algorithms. 
         [0025]    Examples of wearable device  180  and one or more components, including flexible substrates and/or conductive structures, as well as electrodes, may be described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0026]      FIG. 2  is a diagram showing a side view of an orientation of a portion of a flexible substrate, according to some embodiments. Diagram  200  includes an encapsulated component associated with a rigid region  204  through which flexible substrate  207  passes through substantially parallel to line  240 . Flexible substrate  207  is coupled to framework  210  in region  230  having a surface portion  212  to which line  240  is oriented. According to some examples, a neutral axis  242  can be coextensive with surface portion  212 . In some implementations, angle (“C”)  234  can be less than 3 to 5°. In at least one embodiment, angle  234  can be 0° or substantially 0°. By reducing angle  234  to 0°, gap  232  is reduced, which, in turn, reduces or eliminates potential reliability issues due to the gap. Also, by reducing angle  234  to 0°, a rigid-flex junction  270  is moved closer to or at neutral axis (e.g., an axis along which there is neither tension nor compression). Rigid-flex junction  270  is a location at which a flexible substrate  207  couples to a substantially rigid substrate  272  of, for example, a battery enclosure  202  for housing a battery. In view of the foregoing, orienting a portion of flexible substrate  207  to be substantially parallel to surface portion  212  can reduce stresses the same- or differently-sized frameworks. Note that in region  230 , flexible substrate  207  transitions from a distance from surface portion  212  to intersect surface portion  212  at rigid-flex junction  270 . 
         [0027]      FIG. 3  is a diagram showing a side view of a flexible substrate including components coupled to a framework, according to some examples. Diagram  300  shows a flexible substrate  312  formed in a component  310  (e.g., an encapsulated component), whereby a portion of flexible substrate  312  is or is substantially parallel to surface portions  314  of the framework. Diagram  330  in an example configuration indicative of the disposition of the configuration shown in  FIG. 2 . In some examples, a component within  310  can be overmolded or encapsulated with a low pressure molding material. 
         [0028]      FIG. 4  is a diagram depicting translation of a component, according to some examples. Initially, encapsulated component  404  is coupled via flexible substrate  407  to component  402 , which is disposed at rigid region  440 . To reduce stress subsequent to a molding operation, component  404  is translated in direction  430  along surface portion  412  of a framework. By moving component  404  closer to component  402 , a portion of flexible substrate  407  aggregates or otherwise folds upon itself in region  409 . Thus, an amount of conductive material between components  402  and  404  (i.e., a supported flex region) is increased in a smaller space between components  402  and  404 . The portion of flexible substrate  407  in region  409  provides for stress relief. According to some examples, component  404  can be translated a distance of zero 0.5 mm to achieve reduce stresses. 
         [0029]      FIG. 5  is a diagram showing a side view of a flexible substrate including components translated relative to a framework, according to some examples. Diagram  500  shows a flexible substrate  407  formed to couple component  404  (e.g., an encapsulated component) to component  402 , as depicted in diagram  550 . 
         [0030]      FIG. 6  is an example of a flow for translating a component for a flexible substrate, according to some embodiments. Flow diagram  600  is initiated at  602  at which a framework portion includes a surface as reference for orienting a component and/or a flexible substrate. At  604 , a flexible substrate is formed. At  606  a supported flex region is implemented, for example, between two components. Rigid region (e.g., including an region) can be implemented at  608 , and can be aligned with a neutral axis or the portion of the framework at  610 . At  612 , and encapsulated rigid region can be moved or translated along a framework surface. Then, at  614 , the encapsulated rigid region can be molded over during a molding operation. 
         [0031]      FIG. 7  is a diagram showing a side view of an orientation of a portion of another example of a flexible substrate, according to some embodiments. Diagram  700  depicts elements having structures and/or functions as similarly-named or similarly-numbered elements of  FIG. 2 . Further, diagram  700  depicts a device or component (e.g., logic and/or a circuit, such as a bioimpedance circuit, a radio circuit, such as BlueTooth® circuitry or NFC circuitry, or an antenna structure) associated with a rigid region  704  (which may or may not include a substrate, such as a semi-rigid or rigid PCB or semiconductor) from which flexible substrate  707  passes substantially parallel to line  740 . 
         [0032]    In this example, the flexible substrate is an electrode bus  707  that may be coupled to a portion of framework shown as cradle  702 , which may be configured to rigidly house circuitry and to secure a strap band  711  and/or a band (e.g., a molded strap) to each other. In some cases, a surface portion  712  of an anchor portion of cradle  702  may be coextensive with a neutral axis  742  can be coextensive. In some implementations, angle (“C”)  734  can be modified to reduce or negate a gap  732 , which, in turn, reduces or eliminates potential reliability issues due to a gap. Also, by reducing angle  734  (e.g., to 0°), a rigid-flex junction  770  is moved closer to or at neutral axis (e.g., an axis along which there is neither tension nor compression). Note that in some examples, surface portion  712  of an anchor portion of cradle  702  is located higher, such as at  770   a.    
         [0033]    Rigid-flex junctions  770  and  770   a  may be locations at which conductors of an electrode bus  707  couples to a substantially rigid substrate of, for example, a circuit housed in cradle  702 . In view of the foregoing, orienting a portion of flexible substrate  707  to be substantially parallel to surface portion  712  can reduce stresses the same- or differently-sized frameworks. Note that in region  730 , an electrode bus as a flexible substrate  707  transitions from a distance from surface portion  712  to intersect surface portion  712  at rigid-flex junction  770 . 
         [0034]    Examples of one or more components of a wearable device, including flexible substrates and/or cradles and anchor portions, as well as electrodes, may be described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0035]      FIG. 8  depicts an example of a wearable device assembly in which an electrode bus as a flexible substrate may be coupled to circuitry in a housing, according to some embodiments. Diagram  800  of  FIG. 8  depicts a wearable device in an exploded front-half view, the wearable device including a top pod cover  802  and a bottom pod cover  806  that may be configured to enclose an interior region within a cradle  807  having anchor portions  809  that securely couples strap and/or band  820  to cradle  807 . Strap band  820  is shown to include an inner portion  820   a  upon which an electrode bus  831  is disposed thereupon. Electrode bus  831  includes electrodes  833  and conductors (e.g., Kevlar™ fiber-based conductors) coupled between electrodes  833  and circuitry within cradle  807 . In some embodiments, a near field communications (“NFC”) system  812  can be disposed in contact on electrode bus  831 , which may support NFC system  812 . Near field communication system  812  may include an antenna to receive/transmit via NFC protocols, and an active near field communication semiconductor device to receive/transmit data. An outer portion  820   b  is then formed to encapsulate electrode bus  831  and NFC system  812  in portions  820   b  and  820   a  to form strap band  820 , which is anchored at anchor portion  809  to cradle  807 . Or, band  820  may encapsulate a short-range antenna (not shown), such as a Bluetooth® LE antenna, and attaches to cradle  807  at anchor point  809 . As shown, the surface portion of anchor portion may give rise to a rigid-flex junction  770   a  at which conductors of electrode bus  707  couple to circuitry in cradle  807 . 
         [0036]    Examples of one or more components of a wearable device, including flexible substrates and/or cradles and anchor portions, as well as electrodes, may be described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0037]      FIGS. 9A and 9B  are diagrams depicting different views of an example of an electrode bus as a flexible substrate, according to some embodiments. Diagram  900  of  FIG. 9A  is a top view in which electrodes  902  may be positioned on bus substrate in alignment with an axis  901 . There may be more or fewer electrodes  902  disposed on bus substrate  901  than depicted and those electrodes  902  may be positioned in alignment with each other or some or all of the electrodes  902  may not be aligned with one another. Bus substrate  901  may have a different shape than depicted. For example, bus substrate  901  may have a taper  902  in its width. Conductors  912 , which be composed of resilient conductive structures (e.g., wire spun around Kevlar fibers), may be routed along a path in the bus substrate  901 . The path may be determined by one or more wire guides  925  (depicted in dashed line) positioned in a mold or jig (not shown) that may be used to form the electrode bus  900 . Wire guides  925  may include a slot or channel  925   c  in which a portion of conductor  912  may be disposed. The portions of conductors  912  at distal end  909  are the portions of the flexible substrate that may couple to a cradle at a rigid-flex junction, according to some examples. Other examples of resilient conductive structures are disclosed in U.S. patent application Ser. No. 14/______ filed Nov. 13, 2014 with Attorney Docket No. ALI-345 titled “CONDUCTIVE STRUCTURES FOR A FLEXIBLE SUBSTRATE IN A WEARABLE DEVICE,” which is incorporated by reference herein. 
         [0038]    Diagram  950  of  FIG. 9B  is a side view  950  in which electrodes  902  may extend outward of lower surface  901   b  of bus substrate  901  (e.g., oriented toward blood vessels, such as a radial artery and an ulnar artery). Electrode bus  900  may be formed from a material, such as Titanium Nitride or Titanium Carbide, and may include components (e.g., core-reinforced wires) configured to allow flexing, pulling, stretching, twisting of the wire bus  900  as denoted by  903 . The material for bus substrate  901  and its associated components may be selected to withstand a range of torsional loads that may be applied to the wire bus  900  and/or strap bands the wire bus  900  is positioned in. 
         [0039]    In one example, electrodes  902  of a strap band may be configured to sense signals, such as biometric signals (or GSR, etc.), from structures of body/tissue portion at in a target region. As one non-limiting example, the structure of interest may include a radial artery and an ulnar artery. A heart pulse rate may be detected by blood flow through the radial and ulnar arteries, and particularly from the radial artery. Accordingly, a strap band and electrodes  902  may be positioned within the target region to detect biometric signals associated with the body, such as heart rate, respiration rate, activity in the sympathetic nervous system (SNS) or other biometric data, for example. In one example, a pair of electrodes  902   a  may be positioned on electrode bus to be adjacent one of the radial and ulnar arteries and a pair of electrodes  902   b  may be positioned on the electrode bus to be adjacent to the other artery. 
         [0040]    Examples of one or more components of a wearable device, including flexible substrates and electrode busses, may be described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0041]      FIG. 10  is a diagram showing a side view of an electrode bus including components translated relative to a portion of a framework, such as a cradle, according to some examples. Diagram  1000  shows a flexible substrate  707  formed to couple component  1070  (e.g., an encapsulated or unencapsulated component, such as a battery, logic, a semiconductor device, an antenna, a vibratory motor, etc.) to a component (e.g., circuit) dispose in cradle  807 , as depicted in diagram  1050 . Rigid-flex junction point  770   a  is shown to be located between (or substantially in between or in the middle) top surface  1001  and bottom surface of cradle  807 . In some examples, rigid junction point  770   a  may arise at an interface  1020  of a wearable device  1080 , whereby interface  1020  includes an interface between a wearable pod (e.g., including circuitry in a cradle) and a strap or band. A rigid or semi-rigid substrate  1072  may be optional to provide support for component  1070 . In some cases, an encapsulated rigid region may include pre-molding (e.g., during a “first shot” of molding), and may include an antenna or portions of an electrode bus. 
         [0042]    Examples of one or more components of a wearable device may be described in U.S. patent application Ser. No. 14/480,628 (ALI-516) filed on Sep. 8, 2014, which is herein incorporated by reference. 
         [0043]    Although the foregoing examples have been described in some detail for purposes of clarity of understanding, the above-described inventive techniques are not limited to the details provided. There are many alternative ways of implementing the above-described invention techniques. The disclosed examples are illustrative and not restrictive.