Abstract:
The present invention relates to a finger-motion detecting apparatus and method and includes a sensing unit to be disposed on a wrist of a subject person, said sensing unit being configured to output a measurement signal into the wrist of the subject person and to receive a reflected signal of the measurement signal according to the motion of tendons in the wrist of the subject person, a signal control unit configured to control whether the measurement signal is outputted and to adjust the measurement signal on the basis of the reflected signal, and a finger-motion recognizing unit configured to detect finger motion of the subject person from the reflected signal. According to the present invention, since a sensor capable of detecting finger motion is worn on a wrist, the problem of inconvenience in existing methods is resolved.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to Korean Patent Application No. 10-2009-0079964 filed on Aug. 27, 2009 and Korean Patent Application No. 10-2010-0028467 filed on Mar. 30, 2010, the entire contents of which are herein incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a finger-motion detecting apparatus and method, and in particular, a finger-motion detecting apparatus and method which detects finger motion by measuring, as a reflected signal of a measurement signal, a change in the carpal tunnel of a wrist, in which a finger flexor tendons controlling finger motion exist. 
         [0004]    2. Description of the Related Art 
         [0005]    With recent advances in information technology, various user interface schemes have been developed to use computers using new input modals such as voice, multi-touch, and gestures, which are different from existing methods such as mouses and keyboards. 
         [0006]    In particular, there have been many attempts to detect a motion of a hand or finger according to user&#39;s intentions in order to apply it as a user interface, and even now, researches in various fields are being conducted. 
         [0007]    As representative examples of such technology, there are LightGlove, which has an image acquiring device such as an image sensor and an infrared emission unit that is worn on the palm side of a wrist, and detects finger motion by acquiring infrared images reflected from fingers, and Scurry, which is a watch-shaped device and ring devices including acceleration sensors worn on a wrist and fingers, respectively, and detects finger motion. Also, there are Kitty, which uses a sensing device having a conducting wire shape wound around a hand to detect finger motion by touch between fingers, and a finger motion method using an EMG. In addition, there is GestureWrist, which can recognize hand gestures but not finger motion. 
         [0008]    However, the above-mentioned existing technology should attach a device on a palm or fingers due to a signal detection structure. For this reason, user&#39;s activities are limited and it is inconvenient for a user to live in daily life while wearing a device. 
       SUMMARY OF THE INVENTION 
       [0009]    Accordingly, it is an object of the present invention to provide a finger-motion detecting apparatus and method which detects finger motion by measuring a change in a carpal tunnel of a wrist, in which a finger flexor tendons controlling finger motion exists, as a reflected signal of a measurement signal such as an optical or ultrasonic wave signal. 
         [0010]    It is another object of the present invention to suggest various examples, that control various apparatus by finger motion only and use a computer user interface as a hand motion for determine the start and end of a hand gesture in a user interface using hand gestures by additionally using an acceleration sensor or a gyro sensor. 
         [0011]    According to an aspect of the present invention, it is provided a finger-motion detecting apparatus including: a sensing unit to be disposed on a wrist of a subject person, said sensing unit being configured to output a measurement signal into the wrist of the subject person and to receive a reflected signal of the measurement signal according to the motion of tendons in the wrist of the subject person; a signal control unit configured to control whether the measurement signal is outputted and to adjust the measurement signal on the basis of the reflected signal; and a finger-motion recognizing unit configured to detect finger motion of the subject person from the reflected signal. 
         [0012]    The sensing unit may output the measurement signal to a carpal tunnel containing the tendons controlling the motion of fingers. 
         [0013]    The signal control unit may adjust at least one of the strength of a signal output, the frequency of a signal output, a signal output time point, and a signal output cycle regarding the measurement signal. 
         [0014]    The signal control unit may sense a signal regarding the finger motion by triggering the reflected signal. 
         [0015]    The finger-motion recognizing unit may detect the finger motion from the waveform of the signal regarding the finger motion. 
         [0016]    The finger-motion recognizing unit may determine a time block having a time period for processing the signal regarding the finger motion and buffer the signal input until end point of the time block. 
         [0017]    The finger-motion recognizing unit may determine the start and end of the time block in reference to time points when predetermined finger motions are sensed. 
         [0018]    The sensing unit may further comprise an acceleration sensor or a gyro sensor configured to sense hand motion of the subject person, and the finger-motion recognizing unit may determine the start and end of the determined time block on the basis of time points when the acceleration sensor or the gyro sensor senses predetermined hand motions. 
         [0019]    The measurement signal may have at least one form of an infrared ray, a laser, and an ultrasonic wave. 
         [0020]    The finger-motion detecting apparatus may further include a command generating unit configured to generate a command corresponding to the finger motion. 
         [0021]    According to another aspect of the present invention, it is provided a finger-motion detecting method including: outputting a measurement signal into a wrist of an subject person; receiving a reflected signal of the measurement signal according to the motion of tendons in the wrist of the subject person; adjusting the measurement signal on the basis of the reflected signal; and detecting finger motion of the subject person from the reflected signal during a time period when the measurement signal is output while being adjusted. 
         [0022]    In the outputting of the measurement signal, the measurement signal may be output into the carpal tunnel containing the tendons controlling the finger motion. 
         [0023]    In the adjusting of the measurement signal, at least one of the strength of a signal output, the frequency of a signal output, a signal output time point, and a signal output cycle regarding the measurement signal may be adjusted. 
         [0024]    The detecting of the finger motion may further include sensing a signal regarding the finger motion by triggering the reflected signal. 
         [0025]    In the detecting of the finger motion, the finger motion may be detected from the waveform of the signal regarding the finger motion. 
         [0026]    The detecting of the finger motion may include determining a time block having a time period for processing the signal regarding the finger motion, and buffering the signal input until end point of the time block. 
         [0027]    The detecting of the finger motion may further include determining the start and end of the time block in reference to time points when predetermined finger motions are sensed. 
         [0028]    The measurement signal may be in a form of at least one of an infrared ray, a laser, and an ultrasonic wave. 
         [0029]    The finger-motion detecting method may further include generating a command corresponding to the finger motion. 
         [0030]    According to embodiments of the present invention, since a sensor capable of detecting finger motion is worn on a wrist, a problem of inconvenience in existing methods is resolved. Therefore, embodiments of the present invention can be used as a new interface method in a wearable computing field which requires a user to use a computer without being inconvenienced while living daily life normally, that is, being hands free without holding an apparatus. 
         [0031]    Moreover, according to embodiments of the present invention, it is possible to easily detect the motion of each finger without requiring a separate motion sensor by measuring, as a reflected signal, a change in the carpal tunnel of a wrist, where the finger flexor tendons controlling finger motion exists. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]      FIG. 1  is a view illustrating a system adapting a finger-motion detecting apparatus according to an embodiment of the present invention; 
           [0033]      FIG. 2  is a view illustrating the principle of the finger-motion detecting apparatus according to the embodiment of the present invention; 
           [0034]      FIG. 3  is a block diagram illustrating the configuration of the finger-motion detecting apparatus according to the embodiment of the present invention; 
           [0035]      FIG. 4  is a flowchart illustrating operational steps of a finger-motion detecting method according to another embodiment of the present invention; and 
           [0036]      FIGS. 5 and 6  are views illustrating finger-motion detecting apparatuses according to other embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    Embodiments of the present invention will be described hereinafter with reference to the accompanying drawings. 
         [0038]      FIG. 1  is a view illustrating a system adapting a finger-motion detecting apparatus according to an embodiment of the present invention. 
         [0039]    As shown in  FIG. 1 , a finger-motion detecting apparatus  100  according to an embodiment of the present invention is worn on a wrist of a subject person and detects finger motion on the basis of the motion of finger flexor tensions in the wrist according to the finger motion. At this time, the finger-motion detecting apparatus  100  generates a control command corresponding to the detected finger motion and transmits the control command to a control device  200  to control the operation of the control device  200 . 
         [0040]    Therefore, the subject person can control the operation of the control device  200  according to finger motion by wearing only the finger-motion detecting apparatus  100  according to the embodiment of the present invention on the wrists. 
         [0041]      FIG. 2  is a view illustrating the principle of the finger-motion detecting apparatus according to the embodiment of the present invention. 
         [0042]    As shown in  FIG. 2 , finger flexor tendons controlling the motion of individual fingers exists in the carpal tunnel  13  of a wrist. The finger-motion detecting apparatus  100  is worn on the wrists of the subject person so that a sensing unit  110  thereof is in contact with the wrists of the subject person. 
         [0043]    When a transmitter  111  of the sensing unit  110  outputs a measurement signal for detecting finger motion into the wrist, a receiver  115  receives a reflected signal reflected from tendons  12  in the wrist. In this way, the finger-motion detecting apparatus  100  recognizes the motion of the tendons  12  from the reflected signal and detects finger motion according to the motion of the tendons  12 . 
         [0044]    The finger-motion detecting apparatus according to the embodiment of the present invention will now be described in detail with reference to  FIG. 3 . 
         [0045]      FIG. 3  is a block diagram illustrating the configuration of the finger-motion detecting apparatus according to the embodiment of the present invention. 
         [0046]    As shown in  FIG. 3 , the finger-motion detecting apparatus  100  according to the embodiment of the present invention includes a sensing unit  110 , a signal amplifying unit  120 , a signal control unit  130 , a finger-motion recognizing unit  140 , a command generating unit  150 , and a communicating unit  160 . 
         [0047]    The sensing unit  110  is disposed on the wrist of the subject person, and in particular, disposed to be in contact with the skin  11  of the wrist. 
         [0048]    The sensing unit  110  includes a transmitter  111  and a receiver  115 . The transmitter  111  outputs a measurement signal into the wrist of the subject person. At this time, the transmitter  111  outputs the measurement signal to the carpal tunnel  13  which contains the tendons  12  controlling finger motion. The measurement signal is in the form of at least one of an infrared ray, a laser, and an ultrasonic wave. 
         [0049]    The receiver  115  receives a reflected signal of the measurement reflected according to the motion of the tendons  12  in the wrist of the subject person. 
         [0050]    The signal amplifying unit  120  amplifies the reflected signal and then transmits the reflected signal to the signal control unit  130 . The signal control unit  130  controls whether the transmitter  111  outputs the measurement signal and adjusts the measurement signal on the basis of the reflected signal. At this time, the signal control unit  130  adjusts at least one of the strength of a signal output, the frequency of a signal output, a signal output time point, and a signal output cycle regarding the measurement signal to detect optimal conditions capable of sensing change of tendons  12  in the wrist. 
         [0051]    The signal control unit  130  senses a signal regarding finger motion by triggering the reflected signal. At this time, if sensing a signal regarding finger motion greater than or equal to a reference value, the signal control unit  130  transmits the sensed signal to the finger-motion recognizing unit  140 . 
         [0052]    The finger-motion recognizing unit  140  analyzes the reflected signal to detect finger motion of the subject person. Preferably, the finger-motion recognizing unit  140  detects finger motion from the waveform of the signal regarding finger motion. 
         [0053]    That is, the reflected signal has different waveforms according to the motion of the individual tendons  12 . For this reason, the finger-motion recognizing unit  140  recognizes the motion of the individual tendons  12  from the waveform of the reflected signal and detects finger motion corresponding to the motion of a corresponding tendon  12 . 
         [0054]    Meanwhile, the finger-motion recognizing unit  140  determines the start and end of a time block in reference to a time point when signals regarding predetermined finger motions are sensed. As an example, if receiving a predetermined finger motion or a predetermined hand motion by finger motion, which indicates the start, the finger-motion recognizing unit  140  determines the start of the time block in reference to the sense time point. Moreover, if sensing predetermined finger motion or predetermined hand motion by finger motion, which indicates the end, the finger-motion recognizing unit  140  determines the end of the time block on the sense time point. 
         [0055]    At this time, the finger-motion recognizing unit  140  buffers an input signal until end point of the time block and analyzes the signal regarding finger motion from the buffered signal. 
         [0056]    The command generating unit  150  generates a control command corresponding to the detected finger motion. Then, the communicating unit  160  transmits the control command generated by the command generating unit  150  to the control device  200  to control the operation of the control device  200 . 
         [0057]    Another embodiment in which an acceleration sensor or a gyro sensor is added to the sensing unit  110  of the above-mentioned embodiment can be used for more various applications. In this case, finger motions can be used to make motions of pressing down and releasing such as a click and release function, which are the functions of a mouse used for a computer. It is very difficult for an operation recognition system to determine the start and end of hand gestures made in space, and the start and end of hand gestures should be determined to enable a gesture recognizing apparatus to make a correct determination. At this time, it can be applied to determine the start and end of hand gestures with motions of pressing down and releasing with a finger according to a finger-motion detecting method proposed in this specification. 
         [0058]    The operation of an embodiment of the present invention having a configuration as described above will be described below. 
         [0059]      FIG. 4  is a flowchart illustrating operational steps of a finger-motion detecting method according to another embodiment of the present invention. 
         [0060]    As shown in  FIG. 4 , the finger-motion detecting apparatus  100  outputs the measurement signal into the wrist of the subject person (S 400 ), and then receives the reflected signal of the measurement signal according to the motion of the tendons  12  in the wrist of the subject person (S 410 ). 
         [0061]    At this time, the finger-motion detecting apparatus  100  outputs the measurement signal into the carpal tunnel  13  containing the tendons  12  controlling the motion of fingers. Here, the measurement signal is in the form of at least one of an infrared ray, a laser, and an ultrasonic wave. 
         [0062]    When receiving the reflected signal, the finger-motion detecting apparatus  100  continuously outputs the measurement signal into the wrist of the subject person while adjusting the measurement signal on the basis of the reflected signal. At this time, the finger-motion detecting apparatus  100  adjusts at least one of the strength of a signal output, the frequency of a signal output, a signal output time point, and a signal output cycle regarding the measurement signal. 
         [0063]    During a period when the finger-motion detecting apparatus  100  outputs the measurement signal while adjusting the measurement signal, it senses a signal regarding finger motion by triggering the reflected signal. If sensing a signal regarding finger motion (S 420 ), it determines a reference time period of the time block for processing the signal regarding finger motion (S 430 ). At this time, it determines the start and end of the time block in reference to time points when predetermined finger motions are sensed. 
         [0064]    Next, the finger-motion detecting apparatus  100  buffers an input signal until end point of the time block determined in S 430  (S 440 ). At this time, the finger-motion detecting apparatus  100  analyzes the signal regarding finger motion on the basis of the signal buffered in S 440  and detects the finger motion of the subject person from the analysis results (S 450 ). 
         [0065]    At this time, it may receive a signal from an acceleration sensor or a gyro sensor and detect the finger motion of the subject person on the basis of the signal input from the acceleration sensor or the gyro sensor until end point of the time block determined in S 430 . 
         [0066]    Then, the finger-motion detecting apparatus  100  generates a command corresponding to the finger motion detected in S 450  (S 460 ) and transmits the command to the control device  200  to control the operation of the control device  200  (S 470 ). 
         [0067]    Thereafter, if sensing another finger motion (S 480 ), S 430  and subsequent steps are repeatedly performed. 
         [0068]      FIGS. 5 and 6  are views illustrating finger-motion detecting apparatuses according to other embodiments of the present invention. 
         [0069]    First,  FIG. 5  shows a finger-motion detecting apparatus having a plurality of sensing units as an embodiment. The embodiment of  FIG. 5  has a plurality of sensing units  110  arranged in a line, making it possible to detect the motion of the tendons  12  over a wider area. Therefore, the finger-motion detecting apparatus  100  according to this embodiment can more exactly detect finger motion on the basis of reflected signals received by the plurality of sensing units  110 . 
         [0070]    Meanwhile, a control device  200  can use the finger-motion detecting apparatus  100  having the plurality of sensing units  110  as an input device. The control device  200  controls playback, a skip to the previous or next music track, volume adjustment, and the like on the basis of a control signal output from the finger-motion detecting apparatus  100 . 
         [0071]    At this time, the finger-motion detecting apparatus  100  transmits the control signal to the control device  200  in a radio communication scheme such as Bluetooth or RF. 
         [0072]    Meanwhile,  FIG. 6  shows a finger-motion detecting apparatus having an acceleration sensor or a gyro sensor capable of detecting hand motion as an embodiment. 
         [0073]    In this case, an acceleration or gyro sensor  110   a  may be provided in or separately from a sensing unit  110  of the finger-motion detecting apparatus  100 . 
         [0074]    If the finger-motion recognizing unit  140  determines the time block, the acceleration or gyro sensor  110   a  senses hand motion until end point of the time block. 
         [0075]    Accordingly, the finger-motion recognizing unit  140  detects the hand motion of the subject person on the basis of a signal input by the acceleration or gyro sensor  110   a  until end point of the determined time block. 
         [0076]    Similarly, the finger-motion detecting apparatus  100  generates a control signal corresponding to the hand motion, and transmits the control signal to a control device  200  in a radio communication scheme such as Bluetooth or RF. The control device  200  controls playback, a skip to the previous or next music track, volume adjustment, and the like on the basis of a control signal output from the finger-motion detecting apparatus  100 . 
         [0077]    Although the finger-motion detecting apparatuses and method according to the embodiments of the present invention have been described above with reference to the accompanying drawings, they are used in a generic and descriptive sense only and not for purposes of limitation. It will be apparent to those skilled in the art that modifications and variations can be made in the present invention without deviating from the spirit or scope of the invention.