Abstract:
Automated optical inspection of a wearable device and/or sub-assemblies of the wearable device in-situ in an ambient environment where temperature and ambient lighting are need not be controlled are described. A key gold unit for the wearable device or a subassembly of the wearable device may be mounted to an automated optical inspections system that captures images of the key gold unit, converts the image from a color space it was captured in to a Hue, Saturation and Value/Brightness color space. Units under test are imaged while stationary or while being rotated (e.g., 360 degrees) and are imaged. Image data is converted into the Hue, Saturation and Value/Brightness color space and compared with the data from the key gold unit to determine if the unit under test is color matched with the key gold unit. Functionality such as near field communications, capacitive touch, display functionality and others may be tested.

Description:
FIELD 
       [0001]    Embodiments of the present application relate generally to hardware, software, wired and wireless communications, RF systems, wireless devices, wearable devices, biometric devices, health devices, fitness devices, and consumer electronic (CE) devices. 
       BACKGROUND 
       [0002]    Some conventional optical inspection system require environments in which temperature and lighting are controlled in order to produce repeatable results in color matching or image recognition, for example. However, in a production environment it may not be desirable or cost effective to perform conventional optical inspection due to difficulties that may arise in trying to control temperature and lighting conditions, such as color temperature of light and light intensity. Color matching may require expensive optics and digital cameras, that typically operate in a color space that is does not mimic how the human eye perceives color. 
         [0003]    Accordingly, there is a need for apparatus, systems and methods for automated optical inspection that do not require controlled environments and uses a color space that mimics human color perception. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    Various embodiments or examples (“examples”) are disclosed in the following detailed description and the accompanying drawings: 
           [0005]      FIG. 1  depicts one example of a flow diagram for device testing in an automated optical inspection system; 
           [0006]      FIG. 2  depicts one example of a flow diagram for testing a near field communication system in an automated optical inspection system; 
           [0007]      FIG. 3  depicts one example of a flow diagram for testing device functionality in an automated optical inspection system; 
           [0008]      FIG. 4  depicts a side view of a wearable device; 
           [0009]      FIG. 5  depicts a bottom profile view of a wearable device and a top profile view of icons on a cover of the wearable device; 
           [0010]      FIG. 6  depicts examples of different configurations of wearable devices; 
           [0011]      FIG. 7  depicts a profile view of an automated optical inspection system; 
           [0012]      FIG. 8  depicts a side view of an automated optical inspection system; 
           [0013]      FIG. 9  depicts another side view of an automated optical inspection system; 
           [0014]      FIG. 10  depicts a profile view an automated optical inspection system; and 
           [0015]      FIG. 11  depicts icons on device covers being inspected on automated optical inspection system. 
       
    
    
       [0016]    Although the above-described drawings depict various examples of the invention, the invention is not limited by the depicted examples. It is to be understood that, in the drawings, like reference numerals designate like structural elements. Also, it is understood that the drawings are not necessarily to scale. 
       DETAILED DESCRIPTION 
       [0017]    Various embodiments or examples may be implemented in numerous ways, including but not limited to implementation as a device, a wireless device, a system, a process, a method, an apparatus, a user interface, or a series of executable program instructions included on a non-transitory computer readable medium. Such as a non-transitory computer readable medium or a computer network where the program instructions are sent over optical, electronic, or wireless communication links and stored or otherwise fixed in a non-transitory computer readable medium. In general, operations of disclosed processes may be performed in an arbitrary order, unless otherwise provided in the claims. 
         [0018]    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. 
         [0019]    Reference is now made to  FIG. 1  where one example of a flow diagram  100  for device testing in an automated optical inspection system is depicted. At a stage  102  a reference image of a key gold unit that may be used as a color matching reference is captured using an image capture device, such as a three megapixel high definition imaging sensor that may incorporate CMOS image sensors, for example. The image may be captured in a first color space, such as a RGB color space in which there is image data in red, green and blue channels. The key gold unit may be a reference unit that has been previously inspected and determined to be without defect in cosmetics, color or other parameters that justify it being used as a reference against which other devices, such as a wearable device, will be compared. 
         [0020]    At a stage  104  the first color space of the reference image (e.g., a RGB color space) may be converted to reference channels in a Hue, Saturation and Value/Brightness color space (HSV). The data for the reference channels may be stored in memory (e.g., non-volatile memory) of a computer system, for example. 
         [0021]    At a stage  106 , a device (e.g., a device under test) may be loaded into an automated optical inspection system. Image capture devices in the automated optical inspection system may be used to capture the reference image of the key gold unit. The key gold unit may be mounted to the automated optical inspection system or loaded on the automated optical inspection system prior to loading the device. The device may be a model of device that is identical to a model of the key gold unit. The device may be one of many devices in an assembly line or other fabrication process. 
         [0022]    At a stage  108 , images of the device may be captured by one or more image capture devices in the automated optical inspection system. The device may be rotated (e.g., 360 degrees) while the images are being captured. 
         [0023]    At a stage  110 , image data that was captured from the device may be converted from the first color space (e.g., a RGB color space) to channels in the HSV color space. 
         [0024]    At a stage  112 , the data in the channels of the HSV color space that were captured from the device and the data in the reference channels for the image captured from the key gold unit may be analyzed to determine if one or more of the channels differs by a predetermined value from the data in a corresponding reference channel. For example, all channel data from the Hue channels captured from the device may be analyzed with the Hue data in the reference channel to determine if Hue channel differs by a predetermined Hue value from the Hue reference channel. Similarly, Saturation and Value/Brightness channel data may be analyzed to determine if they differ from Saturation and Value/Brightness reference channel data. The predetermined value for Hue, Saturation and Value/Brightness may be different values. The predetermined value may be a delta (Δ) value of a standard value for Hue, Saturation and Value/Brightness. For example, Hue may have a standard value for the key gold unit of 0.445 and the image captured from the device may differ by a delta (e.g., +/−) of 1.097, Saturation may have a standard value of 3.505 and delta of 9.9970, and Value/Brightness may have a standard value of 3.177 and a delta of 31.226. An algorithm executing on a compute engine may use statistical analysis to determine differences in distribution of HSV in the channels for the device from center values of HSV for the reference channels. Wide distributions from the center values are not automatically indicative of a poor color match between the device and the key gold unit and may arise due to coatings or due difference in fine geometric textures of the surface coatings, etc. 
         [0025]    At a stage  114  a determination may be made as to whether or not the flow  100  is done. If a YES branch is taken, then flow  100  may terminate. On the other hand, if a NO branch is taken, then flow  100  may transition to another stage, such as a stage  116 . 
         [0026]    At the stage  116 , results from analysis at the stage  114  may be used to determine whether or not the device is color matched with the key gold unit. At a stage  118 , if the device is not color matched, a NO branch may be taken and the stage  118  may transition to a stage  126  where the device may be determined to have failed automated optical inspection and flow  100  may terminate. If the device is color matched, then a YES branch may be taken and stage  118  may transition to a stage  120  where a determination may be made as to whether or not the device has any cosmetic defects. If a YES branch is taken, then stage  122  may transition to the stage  126 . If a NO branch is taken, then stage  122  may transition to a stage  124  where the device may be determined to have passed automated optical inspection and flow  100  may terminate. Image data for the device that was captured may include data indicative of cosmetic defects including but not limited to scratches, dents, blemishes, scuffs, burning, pin holes, flash (e.g. from a molding process), voids, discoloration, heat marks, shine spots, etc., just to name a few. 
         [0027]    Moving on to  FIG. 2  where one example of a flow diagram  200  for testing a near field communication system in an automated optical inspection system is depicted. The automated optical inspection system described above in reference to  FIG. 1  may be used to test other functionality of the device and that functionality may be tested on one device while another device is being imaged as described above. Therefore, the automated optical inspection system may be configured to perform different tests on different devices at the same time. 
         [0028]    At a stage  202  a device that includes a near field communication (NFC) system may be loaded into the automated optical inspection system. At a stage  204  a near field communication activator and reader, that is included in the automated optical inspection system, may be positioned (e.g., by a robotic system, end effector, actuator, etc.) in near field proximity of the device. Near field proximity may include making a direct contact between the NFC activator and reader and a portion of the device that includes the NFC system, for example. In other examples, near field proximity may include positioning the NFC activator and reader at a distance of about 10 mm or less away from the device or a portion of the device that includes the NFC system. 
         [0029]    At a stage  206  a radio frequency (RF) signal is generated by the NFC activator and reader while the NFC activator and reader is positioned in near field proximity of the device. An antenna coupled with a radio or RF system in the NFC activator and reader may generate the RF signal, for example. 
         [0030]    At a stage  208 , a determination may be made as to whether or not the NFC system was successfully activated by the RF signal generated by the NFC activator and reader. Successful activation may include an NFC antenna of the NFC system generating an electrical signal in response to the RF signal, powering a NFC chip that is coupled with the NFC antenna, and the NFC chip transmitting another RF signal using the NFC antenna. The reader in the NFC activator and reader may be coupled with the radio/RF system of the NFC activator and reader and may read data include in the another RF signal to determine if the data is indicative of successful activation. The data may include financial information used for monetary transactions, such as in a NFC payment system. 
         [0031]    At a stage  210  a determination of successful activation may be made. If activation was successful, a YES branch may be taken and flow  200  may terminate. If activation was not successful, a NO branch may be taken and flow  200  may transition to a stage  210 . At the stage  210  the device, the NFC system or both may be destroyed. If the NFC system is not permanently attached with the device, the NFC system may be removed or otherwise extracted from the device and subsequently destroyed. If the NFC system cannot be removed from the device or may damage the device if removed, then the device may be destroyed. Destruction may include burning in a furnace, pulverizing, smashing, crushing, or using an impact gun, for example. The destruction may be operative to irretrievably destroy the NFC chip in the NFC system. Destruction may be mandated by contract or other agreement with a financial institution or government body. After destruction is verified, flow  200  may terminate. 
         [0032]    Turning now to  FIG. 3  where one example of a flow diagram  300  for testing device functionality in an automated optical inspection system is depicted. At a stage  302  a device is loaded into an automated optical inspection system. At a stage  304  a portion of the device is contacted by an actuator included in the automated optical inspection system. At a stage  306  contact data is captured. Capture may include capturing images of the device, detecting sound (e.g., using a microphone) or vibration (e.g., using an accelerometer) generated by the device, or receiving a signal transmitted by the device (e.g., a RF signal transmitted by the device). Contact by the actuator may activate a display of the device and image capture may be used to determine if the display was activated by the actuator contacting the device. At a stage  308  a determination may be made as to whether or not the contact data indicates successful activation of one or more functions of the device. At a stage  310 , if the one or more functions were successfully activated, a YES branch may be taken to a stage  312  where the device may be determined to have passed contact functionality and flow  300  may terminate. On the other hand, if the one or more functions were not successfully activated, then a NO branch may be taken to a stage  314  where the device may be determined to have failed contact functionality and flow  300  may terminate. The actuator may contact a capacitive touch surface or cover of the device. The actuator may include an end effector operative to mimic a human finger, for example. The device may be powered by an electrical power source included in the automated optical inspection system. The device may include an internal power source (e.g., a rechargeable battery, a lithium ion-type battery, etc.) and the device may be powered up by the internal power source during the functionality testing. The contact by the actuator may be operative to activate the device or wake up the device from a standby or low power state. Functionality testing may include testing of power systems of the device. 
         [0033]    Reference is now made to  FIG. 4  where a side view of a wearable device  400  is depicted. Wearable device  400  may be a device that is loaded into the automated optical inspection system. Device  400  may include strap bands  420  and  430  having inner and outer surfaces ( 420   i,    420   o ) and ( 430   i,    430   o ) respectively. Strap band  430  may include electrodes  432 , a loop  435 , and a buckle  431  including a latch  433 . Strap band  420  may include a latch  421  configured to couple with latch  433 . Loop  435  and latch  421  may be used to secure and hold the device  400  in the automated optical inspection system. Strap bands  420  and  430  may be coupled with a main module  450  that may include circuitry, displays, processors, memory, etc. Main module  450  may include a curved inner surface  450   i,  ornamental features  451  on a cover  453 . Strap bands  430  and  420  may include curved portions  430   c  and  420   c.  Image capture devices in the automated optical inspection system may be panned or otherwise translated along one or more axes to capture images of curved and/or irregular surface of device  400  as device  400  is stationary or rotated (e.g., 360 degrees) in the automated optical inspection system. 
         [0034]    In  FIG. 5  a bottom profile view of the wearable device  400  and a top profile view of icons  571  on the cover  453  of the wearable device  400  are depicted. Icons  571  and/or other functions of device  400  may be activated by contact of a human finger  561  or the above mentioned actuator that may be used to simulate touch of the human finger  561 . Portions of cover  453  may include perforations (e.g., micro-perforations) that define the icons  571 . A light source positioned behind the cover  453  may illuminate the icons  571  in response to contact with cover  453 . Cover  453  may be electrically conductive and may be operative as a capacitive touch switch or surface of the main module  450 . A sequence of contacts with cover  453  or finger gestures on cover  453  may activate one or more functions of device  400 , such as illuminating one or more of the icons  571 . Inner surfaces  450   i  and  430   i  may include surface features  532  and  540 , sensors  511 , and data/charging ports  513 . Optical inspection by one or more image sensors in the automated optical inspection system may be used to detect cosmetic defects in the icons, micro-perforations, surface features, etc. 
         [0035]    In  FIG. 6  examples of different configurations of wearable devices  400   a - 400   m  are depicted. The automated optical inspection system may include an exemplary version of each of the different configuration  400   a - 400   m  as a key gold unit. Due to differences in surface finishes, metal finishes, materials (e.g., fabric, leather, faux leather, thermoplastic elastomers, ornamental details, braiding, colors, strap band types, etc.) a key gold unit for each configuration  400   a - 400   m  may be required for color matching and detection of cosmetic defects, for example. 
         [0036]    Attention is now directed to  FIG. 7  where a profile view of an automated optical inspection system  700  is depicted. System  700  may include posts  711  aligned with a Z-axis and including one or more image capture devices  730 ,  740 , and  750  mounted to  2 -axis servo controlled actuators (e.g., motorized articulated arms)  731 ,  741 , and  751  that are coupled with posts  711 . Image capture devices  730 ,  740 , and  750  may comprise high-definition (HD) CMOS image sensors. Image sensors  730  and  740  may be tasked to capture images of strap bands  420  and  430  and image sensor  750  may be tasked to capture images of cover  453 . A base  799  (e.g., 600 mm on a side) may support pillars  711  and a carousel  710  that includes a plurality of spindles  720  that rotate (e.g., 360 degrees) in the carousel  710  when positioned in front of a spindle drive  770  or  772  (e.g., an edge-friction servo motor). A drive motor coupled with carousel  710  indexes one or more of the spindles  720  in front of image sensors  730 ,  740 ,  750  for image capture. Image sensors  730 ,  740 ,  750  may capture images of device  400  as it is rotated and the image data may be in a color space, such as an RGB color space. A compute engine (e.g., a server, laptop, PC, tablet, pad or other computing resource) may receive the image data and convert it into a HSY color space. One of the spindles  720  or base  799  may carry the key gold unit for the devices  400  being inspected. The image capture devices ( 730 ,  740 ,  750 ) may capture an image of the key gold unit (e.g., while stationary) and the image data may be converted to the HSY color space. System  700  may be positioned next to an assembly line where the devices  400  may be procured and mounted in spindles  720  for inspection and testing. Fastening hardware ( 421 ,  435 ) on devices  400  may be coupled with structure in spindle  720  that stretches out the strap bands ( 420 ,  430 ) to allow for accurate placement of the device  400  in the spindle and accurate imaging of the device  400 . During image capture, the image capture devices may articulate along two-axes (e.g., X and Z) under control of the 2-axis servo controlled actuators  731 ,  741 , and  751 . 
         [0037]      FIG. 8  depicts a side view of the automated optical inspection system  700  and also depicts an actuator  810  with an end effector  820  that may be actuated  821  to contact cover  453  of device  400 . Spring system  830  may couple with latch  421  to secure device  400  in spindle  720 . Image capture device  750  may capture images of cover  453  after contact has been made by actuator  810 . Spindle  720  may include an accelerometer to detect mechanical vibration from device  400  caused by a function activated by contact from actuator  810 . System  700  may include a microphone to capture sound generated by device  400  in response to contact by actuator  810 . 
         [0038]      FIG. 9  depicts another side view of an automated optical inspection system  700  in which the 2-axis controller  751  includes a near field activator and reader  910  having a portion  920  that may be positioned in near field proximity  921  of device  400  and generate a RF signal  923 . Device  400  may generate another RF signal  925  from a NFC system included in device  400 . Successful activation of the NFC system of device  400  may be tested by system  700  as described above in reference to flow  300  of  FIG. 3 . 
         [0039]      FIG. 10  depicts a profile view the automated optical inspection system  700  from a different perspective. In  FIG. 10 , one device  400  may be optically inspected by capture device  730  and  740 , while another device  400  is tested for functionality of it capacitive touch cover  453  by image capture device  750  and actuator  810 . 
         [0040]      FIG. 11  depicts icons  571  on covers  453  being inspected on automated optical inspection system  1100 , which may be system  700  converted over to use for inspection of covers  453 . System  1100  may backlight covers  453  from below carousel  1110  using a diffuse light source and/or a dual collimator light source, for example. Image capture device  1130  mounted on pillar  711  may be positioned over covers  453  as they are indexed into position by a motor coupled with carousel  1110 . Images captured from icons  571  formed by micro-perforations or other in cover  453  are depicted in  1150  and  1160  under diffuse and dual collimator backlighting conditions. The images in  1150  and  1160  may be used to count the number of perforations for each icon  571  and to determine of the icons  571  are defective (e.g., missing perforations, blocked perforations, too many perforations, cosmetic defects in the perforations, etc.). A key gold unit for a cover  453  may be used for color matching of covers  453  being tested and/or for icon  571  inspection using the key gold unit as a reference for known good icons  571 . Other components and/or sub-assemblies of device  400  or other devices may be optically inspected, tested, etc. using system  700  and/or system  1100 . 
         [0041]    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 techniques or the present application. The disclosed examples are illustrative and not restrictive.