Abstract:
Feedback mechanisms to the user of a Head Mounted Display (HMD) are provided. It is important to provide feedback to the user when speech is recognized as soon as possible after the user utters a voice command. The HMD displays and/or audibly renders an ASR acknowledgment in a manner that ensures the user that the HMD has received/understood his voiced command.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/905,130, filed on Nov. 15, 2013. 
         [0002]    This application is related to the following U.S. patent applications: 
         [0003]    U.S. patent application Ser. No. ______, filed Nov. 13, 2014, Attorney Docket No. 0717.2224-001, entitled “Text Selection Using HMD Head-tracker and Voice-Command.” 
         [0004]    U.S. patent application Ser. No. ______, filed Nov. 13, 2014, Attorney Docket No. 0717.2225-001, entitled “Head-Tracking Based Selection Technique For Head Mounted Displays (HMD).” 
         [0005]    U.S. patent application Ser. No. ______, filed Nov. 13, 2014, Attorney Docket No. 0717.2227-001, entitled “Head Tracking Based Gesture Control Techniques For Head Mounted Displays.” 
         [0006]    The entire teachings of the above applications are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0007]    Mobile computing devices, such as a laptop or notebook PC, a smart phone, and tablet computing device, are now common tools used for producing, analyzing, communicating, and consuming data in both business and personal life. Consumers continue to embrace a mobile digital lifestyle as the ease of access to digital information increases with high speed wireless communications technologies becoming ubiquitous. Popular uses of mobile computing devices include displaying large amounts of high-resolution computer graphics information and video content, often wirelessly streamed to the device. While these devices typically include a display screen, the preferred visual experience of a high resolution, large format display cannot be easily replicated in such mobile devices because the physical size of such device is limited to promote mobility. Another drawback of the aforementioned device types is that the user interface is hands-dependent, typically requiring a user to enter data or make selections using a keyboard (physical or virtual) or touch-screen display. As a result, consumers are now seeking a hands-free, high quality, portable, color display solution to augment or replace their hands-dependent mobile devices. 
       SUMMARY OF THE INVENTION 
       [0008]    Recently developed micro-displays can provide large-format, high-resolution color pictures and streaming video in a very small form factor. One application for such displays can be integrated into a wireless headset computer worn on the head of the user with a display within the field of view of the user, similar in format to eyeglasses, audio headset or video eyewear. 
         [0009]    A “wireless computing headset” device, also referred to herein as a headset computer (HSC) or head mounted display (HMD), includes one or more small, high resolution micro-displays and associated optics to magnify the image. The high resolution micro-displays can provide super video graphics array (SVGA) (800×600) resolution or extended graphic arrays (XGA) (1024×768) resolution, or higher resolutions known in the art. 
         [0010]    A wireless computing headset contains one or more wireless computing and communication interfaces, enabling data and streaming video capability, and provides greater convenience and mobility through hands dependent devices. 
         [0011]    For more information concerning such devices, see co-pending patent applications entitled “Mobile Wireless Display Software Platform for Controlling Other Systems and Devices,” U.S. application Ser. No. 12/348,648 filed Jan. 5, 2009, “Handheld Wireless Display Devices Having High Resolution Display Suitable For Use as a Mobile Internet Device,” PCT International Application No. PCT/US09/38601 filed Mar. 27, 2009, and “Improved Headset Computer,” U.S. Application No. 61/638,419 filed Apr. 25, 2012, each of which are incorporated herein by reference in their entirety. 
         [0012]    The present invention relates to use of a Head-Mounted Display (HMD). The HMD is controlled partially by voice-command. The HMD receives speech input from the user, and attempts to recognize the received speech, through various processing techniques, as one of a suite of known voice commands. It is very important for the HMD to provide feedback to the user when received speech is recognized as a speech command, as soon as possible after the spoken command. Doing so helps to deliver a pleasant and efficient experience for the user. 
         [0013]    Embodiments provide feedback mechanisms to the user of a HMD, to ensure that the user feels confident that the unit has understood the spoken commands. 
         [0014]    In one aspect, the invention is a method of acknowledging a voice command. The method includes receiving, by a headset computer, a voice command. The method further includes interpreting the voice command and in response to interpreting the voice command, acknowledging the received voice command. 
         [0015]    One embodiment further includes converting an utterance, which corresponds to the voice command, into an electrical signal. One way of converting the utterance is using a microphone, although other techniques for converting sound into an electrical signal may also be used. 
         [0016]    In another embodiment, interpreting the voice command further includes determining if the voice command is a member of a predetermined suite of voice commands. 
         [0017]    In one embodiment, acknowledging the received voice command includes presenting an automatic speech recognition (ASR) notification clue. The ASR notification clue may include a visual clue. The visual clue may be presented within 500 mS of when the utterance is interpreted, although other periods of time between interpretation of the utterance and presenting the visual clue may be used. The visual clue may be instantiated on a display within two cycles of the frame rate of the display. In another embodiment, the visual clue remains on the display for a predetermined time after the visual clue is instantiated, and removed from the display after the predetermined time has elapsed. 
         [0018]    In some embodiments, the ASR notification clue may include an audio clue, alone or in combination with the visual clue. In one embodiment the audio clue may be a chirp, although other sounds may alternatively be used to indicate recognition of an utterance. 
         [0019]    In another aspect, the invention is apparatus for acknowledging a voice command. The apparatus includes a headset computer configured to receive a voice command, interpret the voice command, and acknowledge the received voice command in response to interpreting the voice command. 
         [0020]    In one embodiment, the apparatus is further configured to convert, using a microphone, an utterance corresponding to the voice command into an electrical signal. 
         [0021]    In another embodiment, the headset computer is further configured to determine if the voice command is a member of a predetermined suite of voice commands. 
         [0022]    In another embodiment, the headset computer is further configured to present an automatic speech recognition (ASR) notification clue. The ASR notification clue may include a visual clue. The visual clue may be presented within 500 mS of when the utterance is interpreted. The visual clue may be instantiated on a display within two cycles of the frame rate of the display. The visual clue may remain on the display for a predetermined time after the visual clue is instantiated, and be removed from the display after the predetermined time has elapsed. 
         [0023]    In one embodiment, the ASR notification clue includes an audio clue. The audio clue may be a chirp. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention. 
           [0025]      FIGS. 1A-1B  are schematic illustrations of a headset computer cooperating with a host computer (e.g., Smart Phone, laptop, etc.) according to principles of the present invention. 
           [0026]      FIG. 2  is a block diagram of flow of data and control in the embodiment of  FIGS. 1A-1B . 
           [0027]      FIG. 3  is a block diagram of automatic speech recognition (ASR) subsystem in embodiments. 
           [0028]      FIG. 4  is a schematic illustration of graphical user interface (GUI) employed in embodiments. 
           [0029]      FIG. 5  is a flow diagram according to one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0030]    A description of example embodiments of the invention follows. 
         [0031]    The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety. 
         [0032]      FIGS. 1A and 1B  show an example embodiment of a wireless computing headset device  100  (also referred to herein as a headset computer (HSC) or head mounted display (HMD)) that incorporates a high-resolution (VGA or better) micro-display element  1010 , and other features described below. 
         [0033]    HSC  100  can include audio input and/or output devices, including one or more microphones, input and output speakers, geo-positional sensors (GPS), three to nine axis degrees of freedom orientation sensors, atmospheric sensors, health condition sensors, digital compass, pressure sensors, environmental sensors, energy sensors, acceleration sensors, position, attitude, motion, velocity and/or optical sensors, cameras (visible light, infrared, etc.), multiple wireless radios, auxiliary lighting, rangefinders, or the like and/or an array of sensors embedded and/or integrated into the headset and/or attached to the device via one or more peripheral ports  1020  ( FIG. 1B ). 
         [0034]    Typically located within the housing of headset computing device  100  are various electronic circuits including, a microcomputer (single or multicore processors), one or more wired and/or wireless communications interfaces, memory or storage devices, various sensors and a peripheral mount or mount, such as a “hot shoe.” 
         [0035]    Example embodiments of the HSC  100  can receive user input through sensing voice commands, head movements,  110 ,  111 ,  112  and hand gestures  113 , or any combination thereof. A microphone (or microphones) operatively coupled to or integrated into the HSC  100  can be used to capture speech commands, which are then digitized and processed using automatic speech recognition techniques. Gyroscopes, accelerometers, and other micro-electromechanical system sensors can be integrated into the HSC  100  and used to track the user&#39;s head movements  110 ,  111 ,  112  to provide user input commands. Cameras or motion tracking sensors can be used to monitor a user&#39;s hand gestures  113  for user input commands. Such a user interface may overcome the disadvantages of hands-dependent formats inherent in other mobile devices. 
         [0036]    The HSC  100  can be used in various ways. It can be used as a peripheral display for displaying video signals received and processed by a remote host computing device  200  (shown in  FIG. 1A ). The host  200  may be, for example, a notebook PC, smart phone, tablet device, or other computing device having less or greater computational complexity than the wireless computing headset device  100 , such as cloud-based network resources. The headset computing device  100  and host  200  can wirelessly communicate via one or more wireless protocols, such as Bluetooth®, Wi-Fi, WiMAX, 4G LTE or other wireless radio link  150 . (Bluetooth is a registered trademark of Bluetooth Sig, Inc. of 5209 Lake Washington Boulevard, Kirkland, Wash. 98033). 
         [0037]    In an example embodiment, the host  200  may be further connected to other networks, such as through a wireless connection to the Internet or other cloud-based network resources, so that the host  200  can act as a wireless relay between the HSC  100  and the network  210 . Alternatively, some embodiments of the HSC  100  can establish a wireless connection to the Internet (or other cloud-based network resources) directly, without the use of a host wireless relay. In such embodiments, components of the HSC  100  and the host  200  may be combined into a single device. 
         [0038]      FIG. 1B  is a perspective view showing some details of an example embodiment of a headset computer  100 . The example embodiment HSC  100  generally includes, a frame  1000 , strap  1002 , rear housing  1004 , speaker  1006 , cantilever, or alternatively referred to as an arm or boom  1008  with a built in microphone, and a micro-display subassembly  1010 . 
         [0039]    A head worn frame  1000  and strap  1002  are generally configured so that a user can wear the headset computer device  100  on the user&#39;s head. A housing  1004  is generally a low profile unit which houses the electronics, such as the microprocessor, memory or other storage device, along with other associated circuitry. Speakers  1006  provide audio output to the user so that the user can hear information. Micro-display subassembly  1010  is used to render visual information to the user. It is coupled to the arm  1008 . The arm  1008  generally provides physical support such that the micro-display subassembly is able to be positioned within the user&#39;s field of view  300  ( FIG. 1A ), preferably in front of the eye of the user or within its peripheral vision preferably slightly below or above the eye. Arm  1008  also provides the electrical or optical connections between the micro-display subassembly  1010  and the control circuitry housed within housing unit  1004 . 
         [0040]    According to aspects that will be explained in more detail below, the HSC display device  100  allows a user to select a field of view  300  within a much larger area defined by a virtual display  400 . The user can typically control the position, extent (e.g., X-Y or 3D range), and/or magnification of the field of view  300 . 
         [0041]    While what is shown in  FIGS. 1A and 1B  is a monocular micro-display presenting a single fixed display element supported on the face of the user with a cantilevered boom, it should be understood that other mechanical configurations for the remote control display device  100  are possible, such as a binocular display with two separate micro-displays (e.g., one for each eye) or a single micro-display arranged to be viewable by both eyes. 
         [0042]      FIG. 2  is a block diagram showing more detail of an embodiment of the HSC or HMD device  100 , host  200  and the data that travels between them. The HSC or HMD device  100  receives vocal input from the user via the microphone, hand movements or body gestures via positional and orientation sensors, the camera or optical sensor(s), and head movement inputs via the head tracking circuitry such as 3 axis to 9 axis degrees of freedom orientational sensing. These are translated by software (processors) in the HSC or HMD device  100  into keyboard and/or mouse commands that are then sent over the Bluetooth or other wireless interface  150  to the host  200 . The host  200  then interprets these translated commands in accordance with its own operating system/application software to perform various functions. Among the commands is one to select a field of view  300  within the virtual display  400  and return that selected screen data to the HSC or HMD device  100 . Thus, it should be understood that a very large format virtual display area might be associated with application software or an operating system running on the host  200 . However, only a portion of that large virtual display area  400  within the field of view  300  is returned to and actually displayed by the micro display  1010  of HSC or HMD device  100 . 
         [0043]    In one embodiment, the HSC  100  may take the form of the device described in a co-pending US Patent Publication Number 2011/0187640, which is hereby incorporated by reference in its entirety. 
         [0044]    The present invention relates to use of an HMD  100  that is capable of being controlled by voice-command. The HMD  100  receives speech input from the user, and attempts to recognize the received speech as one of a predetermined suite of known voice commands. 
         [0045]    It is very important for the HMD  100  to provide feedback to the user when received speech is recognized as a speech command, as soon as possible after the spoken command. Doing so helps to deliver a pleasant and efficient experience for the user. 
         [0046]    The typical Automatic Speech recognition (ASR) system is set up to wait for a predetermined period of time once a speech utterance ceases (i.e., a pause in speech, for example 200 mS) before the system assumes that the user has completed the command. So at a bare minimum there will always be a gap (e.g., 200 mS) after speaking before the ASR subsystem will provide acknowledgment feedback to the user. 
         [0047]    Embodiments of the present invention may provide feedback to the user in visual form, audible form, a command spoken back to the user, or any combination thereof. 
       Visual Feedback 
       [0048]    One way to notify a user that a command was received, and correctly interpreted, is by providing a visual clue, i.e., a clue that can be seen by the user. When a user utters one of a predetermined set of voice commands, the HMD  100  processes the received sound and evaluates the processed information against a set of known voice commands, to generate a proposed interpretation of the sound input. 
         [0049]    In accordance with principles of the present invention, the HMD  100  may display, on screen  1010 , an alert (for example, a pop-up message or other type of notification) for the user, indicating the voice command that the HMD  100  has interpreted. This notification  450  is referred herein to as an ASR (automatic speech recognition) acknowledgement, as shown by the example depicted in  FIG. 4 . In this example, the user may have previously made a selection, perhaps choice “c” from a multiple choice array of “a, b, c or d.” In order to confirm the choice of “c,” the user enunciates “confirm selection.” Thus, as shown in the example of  FIG. 4 , the HMD  100  presents the “confirm selection” notification  450  to the user. 
         [0050]    Empirical data suggests that a user ‘responds’ better to a visual notification presented first with respect to an audio clue. Humans may perceive a visual, onscreen alert more quickly than a counterpart audible alert. Based on this assumption, the at least one of the described embodiments seeks to display the ASR acknowledgment  450  as soon as possible. 
         [0051]    Example embodiments 100 may instantiate the alert within 500 mS (0.5 seconds) of the user voice command being uttered, which may give the system  100  crisply responsive feel, with respect to the ASR. Providing such a timely prompt, indicating that the utterance was received and correctly recognized, may lead to a satisfying experience for the user. 
         [0052]    The system  100  seems more responsive if the ASR acknowledgment  450  just ‘pops’ up rapidly. A slow fade-in visual effect may add unnecessary time to the notification and consequently make the system  100  seem lethargic. A fast fade is generally too fast to really be noticed, and so does not provide any benefit. In an example embodiment, the ASR acknowledgement is completely instantiated within two cycles of the microdisplay&#39;s frame rate, although in other embodiments the ASR acknowledgement may be instantiated more quickly or less quickly. 
         [0053]    One or more embodiments of the system  100  may leave the ASR acknowledgment  450  displayed/illuminated on the screen (display  1010 ) for a predetermined period of time to allow an application executing on the system  100  time to respond. An example amount of time to leave the ASR acknowledgement on the screen may be 1 to 3 seconds, although shorter or longer times may also be used. After the predetermined amount of time has elapsed, the ASR acknowledgement is removed from the display. 
         [0054]    Other embodiments of the system  100  may leave this ASR acknowledgment  450  on the screen of display  1010  until the subject application has finished its current task, regardless of how long it takes to finish. The disappearance of the ASR acknowledgement  450  may be the visual clue that indicates to the user that it is permissible to speak (i.e., utter) the next voice command. 
         [0055]    Example guidelines for visual design of the foregoing ASR acknowledgment  450  may include one or more of: (a) place the ASR acknowledgment in a layer in front of all other content within the screen/display  1010 ; (b) center on screen both vertically and horizontally; (c) preferably run text on only one line (i.e., do not wrap text); (d) keep the height of the box that contains the ASR acknowledgment at a fixed size; and (e) allow the width to vary, depending on length of ASR command feedback. 
       Audible Feedback 
       [0056]    Another way to notify a user that a command was received and correctly interpreted is by providing a clue that can be heard. In one embodiment, an example audio output counterpart to the visual ASR acknowledgement  450  described above may be described as an audible “chirp.” A chirp may consist of a single, short burst of sound. The chirp may have a constant frequency, or it may have a frequency that varies as a function of time. 
         [0057]    The audio notification may be conveyed to the user by itself, or in conjunction with the visual notification. In an embodiment having a combined visual and audio notification, the audio clue may follow the visual clue. In this case, once the visual clue  450  is instantiated on the display screen  1010 , the audio (via speaker  9006 ,  FIG. 3 ) can lag by an additional amount of time (e.g., 500 mS) without a significant effect to the user experience. 
         [0058]    The audio chirp may be user configurable, in that the user can choose, for example, to turn the chirp on or off, vary the volume of the chirp, vary the duration of the chirp or modify the frequency characteristics of the chirp. 
       Command Spoken Back to User 
       [0059]    In alternative audible feedback format (a counterpart to the ASR acknowledgement  450  described herein), the device  100  “speaks back” to the user (using a text-to-speech facility) the command it has interpreted as having been issued (uttered) by the user. 
         [0060]    In the illustrated example, the HMD unit  100  confirms to the user that the spoken command was correctly received by enunciating (via speaker  9006 ) the command ‘Confirm Selection’ back to the user. The spoken command acknowledgement is user configurable in that the user can, for example, choose to turn it on or off, adjust the volume, change the voice characteristics of the enunciation (e.g., male or female voice, language, etc). 
         [0061]    In one embodiment, the user can have either the audible chirp or the text to speech feedback mechanism, or both, for ASR acknowledgement  450 . Although since both are audio clues, embodiments generally do not have both working (rendering) at the same time. 
         [0062]    The system  100  works by using ‘Text-To-Speech’ software  9035   b  to audibly read the phrase recognized (as one of the phrases that the system  100  is ‘listening for’). 
         [0063]    In this way, embodiments of the present invention ensure the user feels confident that the HMD unit  100  has understood their spoken voice commands. 
         [0064]    In one embodiment the HSC  100  may take the form of the HSC described in a co-pending US Patent Publication Number 2011/0187640 which is hereby incorporated by reference in its entirety. 
         [0065]    In another embodiment, the invention relates to the concept of using a Head Mounted Display (HMD)  1010  in conjunction with an external ‘smart’ device  200 , (such as a smartphone or tablet) to provide information and control to the user hands-free. The invention requires transmission of small amounts of data, providing a more reliable data transfer method running in real-time. 
         [0066]    In this sense therefore, the amount of data to be transmitted over the connection  150  is small—simply instructions on how to lay out a screen, which text to display, and other stylistic information such as drawing arrows, or the background colors, images to include, etc. 
         [0067]    Additional data could be streamed over the same  150  or another connection and displayed on screen  1010 , such as a video stream if required by the host  200 . 
         [0068]      FIG. 3  shows an exemplary non-limiting wireless hands-free video computing headset  100  under voice command. The user can be presented with an image on the micro-display  9010 , for example, as output by host computer  200  described above. A user of the HMD  100  can use visual and/or audible ASR acknowledgement software module  9036 , either locally or from a remote host  200 , in which the user is presented with visual and/or audible ASR acknowledgement on the microdisplay  9010  and through the speaker  9006  of the headset computer  100 . Because the headset computer  100  is also equipped with a microphone  9020 , the user can utter voice commands (i.e., make command selections) as illustrated with respect to one or more embodiments of present invention. 
         [0069]      FIG. 3  shows a schematic diagram illustrating the modules of the headset computer  100 .  FIG. 3  includes a schematic diagram of the operative modules of the headset computer  100 . For the case of ASR acknowledgement in speech driven applications controller  9100  accesses ASR acknowledgement module  9036 , which can be located locally to each HMD  100  or located remotely at a host  200  ( FIGS. 1A-1B ). ASR acknowledgement software module  9036  contains instructions to display to a user a screen view  410  of a pertinent message box or the like (examples are detailed in  FIG. 4 ). The graphics converter module  9040  converts the image instructions received from the ASR acknowledgement module  9036  via bus  9103  and converts the instructions into graphics to display on the monocular display  9010 . At the same time text-to-speech module  9035   b  converts instructions received from ASR acknowledgement software module  9036  to create sounds representing the contents for the screen view  410  to be displayed. The instructions are converted into digital sounds representing the corresponding image contents that the text-to-speech module  9035   b  feeds to the digital-to-analog converter  9021   b , which in turn feeds speaker  9006  to present the audio to the user. ASR acknowledgement software module  9036  can be stored locally at memory  9120  or remotely at a host  200  ( FIGS. 1A-1B ). The user can speak/utter the command selection from a screen view  410  and the user&#39;s speech  9090  is received at microphone  9020 . The received speech is then converted from an analog signal into a digital signal at analog-to-digital converter  9021   a . Once the speech is converted from an analog to a digital signal speech recognition module  9035   a  processes the speech into recognized speech. The recognized speech is compared against known speech, and the ASR acknowledgement module  9036  responds according to the instructions as described above. 
         [0070]      FIG. 5  is a flow diagram according to one of the described embodiments. 
         [0071]    It will be apparent that one or more embodiments described herein may be implemented in many different forms of software and hardware. Software code and/or specialized hardware used to implement embodiments described herein is not limiting of the embodiments of the invention described herein. Thus, the operation and behavior of embodiments are described without reference to specific software code and/or specialized hardware—it being understood that one would be able to design software and/or hardware to implement the embodiments based on the description herein. 
         [0072]    Further, certain embodiments of the example embodiments described herein may be implemented as logic that performs one or more functions. This logic may be hardware-based, software-based, or a combination of hardware-based and software-based. Some or all of the logic may be stored on one or more tangible, non-transitory, computer-readable storage media and may include computer-executable instructions that may be executed by a controller or processor. The computer-executable instructions may include instructions that implement one or more embodiments of the invention. The tangible, non-transitory, computer-readable storage media may be volatile or non-volatile and may include, for example, flash memories, dynamic memories, removable disks, and non-removable disks. 
         [0073]    While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.