Abstract:
A detection device including: a sensor configured to emit a light and detect an object by detecting the light reflected from the object, and a processor configured to determine, when the object is detected in a first region that is narrower than a range where the light reaches, a motion of the object to be a gesture input for the detection device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2015-252108, filed on Dec. 24, 2015, the entire contents of which are incorporated herein by reference. 
       FIELD 
       [0002]    Disclosed techniques are related to a detection device, a detection method, and a detection program. 
       BACKGROUND 
       [0003]    In recent years, application of a wearable display device such as a head mounted display (HMD) has been being promoted as a measure to view information at a site of work. At a site where a worker who carries out input operation to an operation screen displayed on the HMD or the like frequently wears a work glove or the like, it is difficult to carry out the input operation by operating an input device such as a touch panel. Therefore, a user interface (UI) with which input operation may be carried out without directly operating an input device such as a touch panel may be required. 
         [0004]    As one UI, a gesture input method in which a finger, a hand, or the like that makes a gesture representing input operation is shot by a camera and the gesture is recognized from the shot image has been proposed. However, at a site of work, it is sometimes difficult to stably carry out the gesture input due to the influence of the movement of the worker, change in the posture of the worker, environmental conditions such as the background color and illumination, and so forth. 
         [0005]    Therefore, a technique in which gesture input is carried out by using a laser sensor that is robust regarding the environmental conditions such as illumination has been proposed. 
         [0006]    For example, there has been proposed a control device based on gesture recognition in which the existence position of a detection-target object is detected from a distance measured by a laser range sensor that measures the distance to the detection-target object that exists in a detection plane. In this control device, the motion of the detection-target object may be detected from time-series data of the detected existence position of the detection-target object and a gesture may be extracted from the motion of the detection-target object. Then, a control command according to the extracted gesture may be generated to be given to control target equipment. 
         [0007]    Furthermore, there has been proposed a method in which a user blocks light from a laser tracker at least partly and thereby a temporal pattern corresponding to one command selected from plural commands by the user is generated. 
       CITATION LIST 
     Patent Documents 
       [0008]    [Patent Document 1] Japanese Laid-open Patent Publication No. 2010-244480 
         [0009]    [Patent Document 2] Japanese Laid-open Patent Publication No. 2013-145240 
       SUMMARY 
       [0010]    According to an aspect of the embodiments, a detection device includes a sensor configured to emit a light and detect an object by detecting the light reflected from the object, and a processor configured to determine, when the object is detected in a first region that is narrower than a range where the light reaches, a motion of the object to be a gesture input for the detection device. 
         [0011]    The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. 
         [0012]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0013]      FIG. 1  is a block diagram illustrating schematic configurations of gesture input systems according to first and second embodiments; 
           [0014]      FIG. 2  is a diagram illustrating one example of mounting of mounted equipment on a user; 
           [0015]      FIG. 3  is a diagram illustrating another example of mounting of mounted equipment on a user; 
           [0016]      FIG. 4  is a diagram for explaining setting of a gesture region; 
           [0017]      FIG. 5  is a diagram for explaining setting of a gesture region according to change in posture; 
           [0018]      FIG. 6  is a diagram illustrating one example of an operation screen; 
           [0019]      FIG. 7  is a block diagram illustrating a schematic configuration of a computer that functions as a detection device; 
           [0020]      FIG. 8  is a flowchart illustrating one example of detection processing in the first embodiment; 
           [0021]      FIG. 9  is a diagram illustrating one example of parameters for setting a gesture region; 
           [0022]      FIG. 10  is a diagram illustrating a relationship among parameters for setting a gesture region; 
           [0023]      FIG. 11  is a schematic diagram of one example of a measurement result; 
           [0024]      FIG. 12  is a diagram for explaining gesture recognition; 
           [0025]      FIG. 13  is a diagram for explaining setting of a gesture start preparation region and a gesture end region; 
           [0026]      FIG. 14  is a diagram illustrating one example of parameters for setting a gesture start preparation region and a gesture end region; 
           [0027]      FIG. 15  is a diagram for explaining detection of an instructing body in the second embodiment; 
           [0028]      FIG. 16  is a flowchart illustrating one example of detection processing in the second embodiment; 
           [0029]      FIG. 17  is a block diagram illustrating a schematic configuration of a gesture input system according to a third embodiment; 
           [0030]      FIG. 18  is a diagram for explaining one example of environment recognition; and 
           [0031]      FIG. 19  is a flowchart illustrating one example of environment recognition processing. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0032]    In the method in which a detection-target object is detected by a laser range sensor, it is difficult to identify whether an object existing in a detection plane is an instructing body (object such a hand or a finger) that makes an instruction of an input by a gesture or an object other than the instructing body. 
         [0033]    Furthermore, the laser range sensor or the like may be set on the environment side. However, at a site of work, it is preferable that gesture input may be carried out not at a fixed place but at arbitrary various places. Therefore, for example, it is conceivable that a worker wears the laser range sensor and thereby the gesture input at arbitrary places is enabled. 
         [0034]    However, in this case, the possibility that an object other than the instructing body that makes an instruction of an input enters the detection plane of the laser range sensor becomes higher. As a result, there is a possibility that an object existing in the detection plane is detected as the instructing body although being an object other than the instructing body. Furthermore, the case in which the instructing body enters the detection plane although a gesture input is not intended is also envisaged. Also in this case, there is a possibility that this instructing body is detected as the instructing body although this instructing body is preferably not detected as the instructing body. 
         [0035]    Disclosed techniques intend to stably detect the instructing body that makes an instruction of an input as one aspect. 
         [0036]    One example of embodiments according to the disclosed techniques will be described in detail below with reference to the drawings. 
       First Embodiment 
       [0037]    As illustrated in  FIG. 1 , a gesture input system  100  according to a first embodiment includes mounted equipment  16 , an HMD  20 , and a server  30 . In the gesture input system  100 , a gesture input carried out by a user who wears the mounted equipment  16  to an operation screen displayed on the HMD  20  based on information provided from the server  30  is accepted. The mounted equipment  16  and the HMD  20  are coupled by short distance wireless communication or the like, for example. The HMD  20  and the server  30  are coupled via a network such as the Internet. 
         [0038]    The mounted equipment  16  includes a detection device  10 , a laser range scanner  17 , and a vibrator  18  that is a vibration mechanism to give vibrations to the mounted equipment  16 . 
         [0039]    The mounted equipment  16  is mounted on part of the body of a user  60 . For example, as illustrated in  FIG. 2 , the mounted equipment  16  may be mounted on a body trunk  60 A (for example, waist) of the user  60  by being fixed to a belt or the like or being directly attached to clothing. 
         [0040]    The laser range scanner  17  is a measurement device of a plane scanning type that measures the distance to an object existing in the surroundings. For example, the laser range scanner  17  includes an emitting unit that emits light such as laser light with scanning in given directions, a light receiving unit that receives reflected light obtained by reflection of the light emitted from the emitting unit by an object existing in the measurement range, and an output unit that outputs the measurement result. 
         [0041]    A measurement range  62  is a plane defined by an aggregation of vectors  64  indicating the emission direction of one time of light emission by the emitting unit corresponding to one scan as illustrated in  FIG. 2 . In the example of  FIG. 2 , the case in which the scanning direction of light by the emitting unit of the laser range scanner  17  is substantially the horizontal direction is illustrated. Therefore, the measurement range  62  is also defined as a plane along substantially the horizontal direction. Furthermore, as illustrated in  FIG. 3 , if the scanning direction of light by the emitting unit of the laser range scanner  17  is substantially the vertical direction, the measurement range  62  is also defined as a plane along substantially the vertical direction. However, the measurement range  62  is not limited to the case in which the measurement range  62  is defined as a plane along substantially the horizontal direction or substantially the vertical direction and may be defined as a plane having an inclination in the horizontal direction or the vertical direction. 
         [0042]    Moreover, the output unit calculates a distance d to a position on an object by which emitted light is reflected based on the time from the emission of the light from the emitting unit to reception of the reflected light by the light receiving unit, and acquires an angle θ when the reflected light from the position is incident on the light receiving unit. Then, the output unit outputs data (d, θ) of the combination of the distance d and the angle θ as the measurement result, for example. If M times of light emission are carried out in one time of scanning, the output unit outputs M pieces of data (d, θ) as the measurement result corresponding to the one time of scanning. This measurement result represents the position of the object in the measurement range  62 . 
         [0043]    As illustrated in  FIG. 1 , the detection device  10  includes an acquiring unit  11 , a setting unit  12 , and a detecting unit  13  functionally. 
         [0044]    The acquiring unit  11  accepts the measurement result output from the laser range scanner  17  and transfers the measurement result to the setting unit  12 . 
         [0045]    The setting unit  12  sets a gesture region  66  defined with envisaging of a region in which an instructing body that makes an input instruction acts in the measurement range  62  of the laser range scanner  17 . For example, suppose that the instructing body that makes an input instruction is the right hand part of the user  60  in the case in which the mounted equipment  16  is mounted on the body trunk  60 A of the user  60  as illustrated in  FIG. 2  and the measurement range  62  is along substantially the horizontal direction. In the present embodiment, a range including the region from the upper arm to the fingertips of the user  60  will be referred to as the hand part. In this case, for example, as illustrated in  FIG. 4 , the range the right hand part is able to reach from the body trunk  60 A may be set as the gesture region  66 .  FIG. 4  is a schematic diagram when the user  60  who wears the mounted equipment  16  and the measurement range  62  are viewed from above and the right side on the plane of paper is the right hand side of the user  60 . 
         [0046]    Here, for example, as illustrated in  FIG. 5 , the measurement range  62  of the laser range scanner  17  included in the mounted equipment  16  is poorly affected by change in the posture of the user  60  if the mounted equipment  16  is mounted on the body trunk  60 A. On the other hand, when gesture input is carried out with the hand part of the user  60 , if the posture of the user  60  changes, particularly if the posture of the upper body changes, the position at which the gesture is carried out with the hand part is readily affected by the change in the posture. Therefore, the setting unit  12  does not set the gesture region  66  fixed with respect to the measurement range  62  but sets the gesture region  66  depending on the change in the posture of the user  60 .  FIG. 5  is a schematic diagram when the user  60  who wears the mounted equipment  16  and the measurement range  62  are viewed from a lateral side in the case in which the measurement range  62  is along substantially the vertical direction. 
         [0047]    The detecting unit  13  detects an object existing in the gesture region  66  as the instructing body that makes an input instruction based on the measurement result of the laser range scanner  17  and the gesture region  66  set by the setting unit  12 . Furthermore, the detecting unit  13  recognizes a gesture based on the motion of the detected instructing body in the gesture region  66 . The detecting unit  13  transmits the input instruction represented by the recognized gesture to the HMD  20 . 
         [0048]    Moreover, when detecting the instructing body in the gesture region  66 , the detecting unit  13  causes the vibrator  18  to vibrate in order to notify the start of gesture recognition. 
         [0049]    Details of the setting method of the gesture region  66  in the setting unit  12  and the recognition method of the gesture in the detecting unit  13  will be described later. 
         [0050]    As illustrated in  FIG. 1 , the HMD  20  includes a display unit  21  on which various kinds of information are displayed and a control unit  22  that controls displaying of information to the display unit  21 . On the display unit  21 , for example, an operation screen like one illustrated in  FIG. 6  is displayed based on information transmitted from the server  30 . When the user  60  who wears the HMD  20  and the mounted equipment  16  makes a gesture in the gesture region  66 , an input instruction is transmitted from the detecting unit  13  as described above. When accepting this input instruction, the control unit  22  carries out display control of the movement of a pointer  68  displayed on the display unit  21 , highlighting of a selected item, or the like in accordance with the input instruction, for example. Furthermore, the control unit  22  transmits information on the selected item to the server  30 . Moreover, the control unit  22  accepts information newly transmitted from the server  30  according to the selected item and carries out display control of the display unit  21 . 
         [0051]    The server  30  is an information processing device such as a personal computer or a server device. 
         [0052]    The detection device  10  included in the mounted equipment  16  may be implemented by a computer  40  illustrated in  FIG. 7 , for example. The computer  40  includes a central processing unit (CPU)  41 , a memory  42  as a temporary storage area, and a non-volatile storing unit  43 . Furthermore, the computer  40  includes an input-output device  44 , a read/write (R/W) unit  45  that controls reading and writing of data from and to a recording medium  49 , and a communication interface (I/F)  46 . The CPU  41 , the memory  42 , the storing unit  43 , the input-output device  44 , the R/W unit  45 , and the communication I/F  46  are coupled to each other via a bus  47 . 
         [0053]    The storing unit  43  may be implemented by a hard disk drive (HDD), a solid state drive (SSD), a flash memory, or the like. In the storing unit  43  as a storage medium, a detection program  50  for causing the computer  40  to function as the detection device  10  is stored. The detection program  50  includes an acquisition process  51 , a setting process  52 , and a detection process  53 . 
         [0054]    The CPU  41  reads out the detection program  50  from the storing unit  43  and loads the detection program  50  into the memory  42  to sequentially execute the processes the detection program  50  has. The CPU  41  operates as the acquiring unit  11  illustrated in  FIG. 1  by executing the acquisition process  51 . Furthermore, the CPU  41  operates as the setting unit  12  illustrated in  FIG. 1  by executing the setting process  52 . Moreover, the CPU  41  operates as the detecting unit  13  illustrated in  FIG. 1  by executing the detection process  53 . This causes the computer  40  that executes the detection program  50  to function as the detection device  10 . 
         [0055]    It is also possible that functions implemented by the detection program  50  are implemented by a semiconductor integrated circuit for example, an application specific integrated circuit (ASIC) or the like for more detail. 
         [0056]    Next, operation of the gesture input system  100  according to the first embodiment will be described. The user  60  wears the mounted equipment  16  and the HMD  20 . Then, when an application offered by the gesture input system  100  is activated, information representing an operation screen is transmitted from the server  30  to the HMD  20  and the operation screen is displayed on the display unit  21  of the HMD  20 . Then, measurement and output of the measurement result by the laser range scanner  17  included in the mounted equipment  16  are started and detection processing illustrated in  FIG. 8  is executed in the detection device  10 . 
         [0057]    First, in a step S 11 , the acquiring unit  11  accepts a measurement result output from the laser range scanner  17  and transfers the measurement result to the setting unit  12 . 
         [0058]    Next, in a step S 12 , the setting unit  12  identifies the measurement range  62  of the laser range scanner  17  based on the measurement result of the laser range scanner  17 . For example, the setting unit  12  identifies whether the measurement range  62  of the laser range scanner  17  is the measurement range  62  along the horizontal direction like that illustrated in  FIG. 2  or the measurement range  62  along the vertical direction like that illustrated in  FIG. 3 . 
         [0059]    Next, in a step S 13 , the setting unit  12  estimates the posture of the user  60  based on the measurement result of the laser range scanner  17 . For example, the setting unit  12  estimates the posture of the user  60  based on the position of a region  60 B that is part of the body of the user  60  detected in the measurement range  62  and is other than the region serving as the instructing body. As the region  60 B of the user  60 , the left hand part or part of the body trunk  60 A (for example, waist) may be employed if the mounted equipment  16  is mounted on the body trunk  60 A and the measurement range  62  is along the horizontal direction and the instructing body is the right hand part, for example. Furthermore, as the region  60 B of the user  60 , the head or part of the body trunk  60 A (for example, chest) may be employed if the mounted equipment  16  is mounted on the body trunk  60 A and the measurement range  62  is along the vertical direction, for example. The measurement result of the laser range scanner  17  indicates the position of an object existing in the measurement range  62 . In addition, from a succession of the position, the shape of the object surface on the side of the laser range scanner  17  may also be recognized. Therefore, the setting unit  12  identifies the region  60 B from the inside of the measurement range  62  based on this shape of the object surface and estimates the position of the identified region  60 B in the measurement range  62  as the posture of the user  60 . 
         [0060]    Next, in a step S 14 , the setting unit  12  sets the gesture region  66  based on parameters defined in advance in order to set the gesture region  66  as illustrated in  FIG. 9  and the posture of the user estimated in the above-described step S 13 , for example. 
         [0061]    In the example of the parameters represented in  FIG. 9 , it is defined that the position of the region  60 B when a sensor 0 point representing one limit point of the scanning direction of the laser range scanner  17  is defined as 0° is employed as a reference angle Th0. The position of the region  60 B is displaced relative to the sensor 0 point and thus the reference angle Th0 is a variable. Furthermore, in the example of the parameters represented in  FIG. 9 , an angle (near region end angle) Th_a from the reference angle Th0 to the near end part of the gesture region  66  and an angle (far region end angle) Th_b to the far end part are defined. Moreover, in the example of the parameters represented in  FIG. 9 , a distance (near region distance) N from the laser range scanner  17  to the near end part of the gesture region  66  and a distance (far region distance) F to the far end part are defined. In  FIG. 10 , the relationship among the laser range scanner  17 , the sensor 0 point, and the parameters Th0, Th_a, Th_b, N, and F is illustrated. 
         [0062]    Here, when the posture of the user  60  changes, the region  60 B of the user  60  with respect to the sensor 0 point is also displaced. Therefore, by employing a variable according to the region  60 B as the reference angle Th0 for defining the gesture region  66 , when the posture of the user  60  changes, the position of the set gesture region  66  also changes as illustrated in  FIG. 10 . 
         [0063]    Furthermore, the proper setting position of the gesture region  66  differs depending on to what region of the user  60  and toward which direction the mounted equipment  16  including the laser range scanner  17  is attached. Therefore, a table like that illustrated in  FIG. 9  is prepared for each of the measurement ranges  62  corresponding to patterns different from each other in the attachment position and attachment direction of the mounted equipment  16 . Then, the parameters Th0, Th_a, Th_b, N, and F for identifying the optimum gesture region  66  when the mounted equipment  16  is attached with the pattern corresponding to a respective one of the measurement ranges  62  are defined for each of the measurement ranges  62  corresponding to a respective one of the patterns. Furthermore, the setting unit  12  selects the table corresponding to the measurement range  62  identified in the step S 12  to acquire the parameters, and sets the gesture region  66  based on the acquired parameters. 
         [0064]    Next, in a step S 15 , the detecting unit  13  determines whether or not an object exists in the gesture region  66  based on the measurement result of the laser range scanner  17  and the gesture region  66  set in the above-described step S 14 . The detecting unit  13  determines that an object exists in the gesture region  66  if a position included in the gesture region  66  defined by the above-described parameters exists among positions represented by plural pieces of data (d, θ) as measurement results of the laser range scanner  17 . For example, suppose that the gesture region  66  is defined with Th0=30 degrees, Th_a=40 degrees, Th_b=90 degrees, N=20 cm, and F=60 cm. In this case, if data of (d, θ)=(40 cm, 80 degrees) exists in measurement results of the laser range scanner  17 , the position represented by (d, θ) is in the gesture region  66  and thus the detecting unit  13  determines that an object exists in the gesture region  66 . θ is an angle of the clockwise direction from the sensor 0 point. 
         [0065]    Then, if an object exists in the gesture region  66 , the detecting unit  13  detects the object as an instructing body  70  that makes an input instruction and the processing makes transition to a step S 16 . On the other hand, if an object does not exist in the gesture region  66 , the processing returns to the step S 11 . 
         [0066]    In the step S 16 , the detecting unit  13  temporarily stores the detection result of the above-described step S 15  in a given storage area. In this storage area, detection results of a given time are stored. The detection result of the object is represented as one shape like a heavy line part in an ellipse A in  FIG. 11  through succession of plural measurement results (d, θ). Therefore, the detecting unit  13  stores the measurement result group representing this one shape as the detection result representing one instructing body  70 . Furthermore, if plural instructing bodies  70  are detected in the gesture region  66 , identification information is given to each instructing body  70  and the detection result is stored about each of the instructing bodies  70 . 
         [0067]    Next, in a step S 17 , the detecting unit  13  causes the vibrator  18  to vibrate in order to notify the start of gesture recognition. 
         [0068]    Next, in a step S 18 , the detecting unit  13  recognizes whether or not the motion of the instructing body  70  is a gesture defined in advance as an input instruction to the operation screen displayed on the display unit  21  of the HMD  20 , based on time-series change in the detection result of the instructing body  70  stored in the given storage area. 
         [0069]    As gestures of the input instruction, a gesture of a direction instruction, gestures of a tap and a double tap, and so forth may be defined, for example. The recognition method of the respective gestures will be described below. 
         [0070]    In  FIG. 12 , one example of gesture recognition is schematically illustrated. The example of  FIG. 12  represents that the instructing body  70  is a hand part with a pointing pose and the instructing body  70  enters the gesture region  66  at point A ( 72 B) from the state in which the instructing body  70  has not entered the gesture region  66  ( 72 A). Furthermore, the example of  FIG. 12  represents that the instructing body  70  moves from point A to point B in the gesture region  66  ( 72 C→ 72 D) and exits from the gesture region  66  at point B ( 72 E). Moreover, in  72 C of  FIG. 12 , it is represented that the size of the detected instructing body  70  is large compared with in  72 B. This represents that, first, a small section (equivalent to the heavy line part in the ellipse A in  FIG. 11 ) is detected when the fingertip enters the gesture region  66  and then a region such as a wrist, whose section is larger than the fingertip, is detected through further advancement of the hand part in such a direction as to pass through the gesture region  66 . As the size of the section, the number of measurement results included in the measurement result group stored as the detection result of one instructing body  70 , the length of the shape represented by the measurement result group, the area of a sectional shape estimated from the shape represented by the measurement result group, and so forth may be used. In addition, in  72 E of  FIG. 12 , it is represented that the size of the detected instructing body  70  is small compared with in  72 D. 
         [0071]    Suppose that the detection result of the instructing body  70  stored in the given storage area represents time-series change of  72 A→ 72 B→ 72 C→ 72 D→ 72 E→ 72 A in  FIG. 12  (flow of white block arrows in  FIG. 12 ). In this case, the detecting unit  13  may recognize that the motion of the instructing body  70  is a gesture of a direction instruction between point A and point B. Furthermore, suppose that the detection result of the instructing body  70  represents time-series change of  72 A→ 72 B→ 72 C→ 72 B→ 72 A in  FIG. 12  (flow of hatched block arrows in  FIG. 12 ). In this case, the detecting unit  13  may recognize that the motion of the instructing body  70  is a gesture of a tap at point A. Furthermore, if a similar tap action is repeated twice in a short time, the detecting unit  13  may recognize the motion of the instructing body  70  as a double tap. 
         [0072]    If plural instructing bodies  70  have been detected in the step S 15 , the position and size of the instructing body  70  are compared between the detection result of the previous time and the detection result of the present time, and the instructing bodies  70  estimated to be the same are associated between the times and are given the same identification information. Then, the motion of each instructing body  70  is identified from time-series change in the detection result given the same identification information. 
         [0073]    If the detecting unit  13  recognizes a gesture of an input instruction, the processing makes transition to a step S 19 . If a gesture of an input instruction is not recognized, the processing returns to the step S 11 . 
         [0074]    In the step S 19 , the detecting unit  13  transmits the input instruction represented by the gesture recognized in the above-described step S 18  to the HMD  20  and the processing returns to the step S 11 . 
         [0075]    Due to this, in the HMD  20 , the control unit  22  carries out display control of the movement of the pointer  68  displayed on the display unit  21 , highlighting of a selected item, or the like based on the input instruction accepted from the detecting unit  13 , for example. Then, the control unit  22  transmits information on the selected item to the server  30 . 
         [0076]    The server  30  transmits information according to the item selected by the user  60  to the HMD  20  based on the information accepted from the control unit  22 . In the HMD  20 , the control unit  22  accepts the newly-transmitted information and carries out display control of the display unit  21  based on the accepted information. 
         [0077]    As described above, according to the gesture input system  100  in accordance with the first embodiment, the user  60  wears the mounted equipment  16  including the laser range scanner  17 . Furthermore, the detection device  10  included in the mounted equipment  16  sets, as the gesture region  66 , a region in which an instructing body  70  that makes an input instruction is conceived to make a gesture in the measurement range  62  of the laser range scanner  17 . Moreover, the detection device  10  detects an object existing in the set gesture region  66  as the instructing body  70  and recognizes a gesture representing an input instruction based on the motion of the instructing body  70  in the gesture region  66 . Due to this, even when an object other than the instructing body  70  or the instructing body  70  that does not intend a gesture of an input instruction enters the measurement range  62  of the laser range scanner  17 , the object or the instructing body  70  is not detected as the instructing body  70  that makes an input instruction if it is not in the gesture region  66 . Therefore, the instructing body  70  may be stably detected. 
         [0078]    Furthermore, according to the detection device  10  in accordance with the first embodiment, the gesture region  66  is set at a proper position according to the posture of the user  60  who wears the mounted equipment  16  including the laser range scanner  17 . Therefore, the instructing body  70  may be stably detected even in work involving posture change. 
       Second Embodiment 
       [0079]    Next, a second embodiment will be described. Regarding a gesture input system according to the second embodiment, the part similar to that of the gesture input system  100  according to the first embodiment is given the same numeral and detailed description of the part is omitted. 
         [0080]    In the first embodiment, description is made about the case in which, if an object exists in the gesture region  66  set by the setting unit  12 , the object is detected as the instructing body  70  that makes an input instruction. In this case, also when an object other than the instructing body  70  or the instructing body  70  that does not intend a gesture of an input instruction enters the gesture region  66 , the object or the instructing body  70  is detected as the instructing body  70  that makes an input instruction. If the detected instructing body  70  is an object other than the instructing body  70  or the instructing body  70  that does not intend a gesture of an input instruction, the possibility that these objects make an action similar to a gesture representing an input instruction defined in advance will be low. Therefore, the possibility that a problem of erroneous recognition of a gesture occurs will also be low, and processing of unnecessary gesture recognition occurs regarding the object other than the instructing body  70  and the instructing body  70  that does not intend a gesture of an input instruction. 
         [0081]    Therefore, in the second embodiment, a target whose gesture is to be recognized as the instructing body  70  among objects that have entered the gesture region  66  is limited so that processing of such unnecessary gesture recognition is reduced. 
         [0082]    As illustrated in  FIG. 1 , a gesture input system  200  according to the second embodiment includes mounted equipment  216 , the HMD  20 , and the server  30 . The mounted equipment  216  includes a detection device  210 , the laser range scanner  17 , and the vibrator  18 . The detection device  210  functionally includes the acquiring unit  11 , a setting unit  212 , and a detecting unit  213 . 
         [0083]    The setting unit  212  sets the gesture region  66  similarly to the setting unit  12  according to the first embodiment. Furthermore, as illustrated in  FIG. 13 , the setting unit  212  sets a partial region in contact with the gesture region  66  as a gesture start preparation region  74 . The gesture start preparation region  74  is a region for determining to start gesture recognition by the detecting unit  213  when the instructing body  70  passes through this region and enters the gesture region  66 . Therefore, a region through which entry into the gesture region  66  is difficult for an object other than the instructing body  70  and the instructing body  70  that does not intend a gesture of an input instruction is defined as the gesture start preparation region  74 . 
         [0084]    For example, suppose that a range the right hand part is able to reach from the body trunk  60 A is set as the gesture region  66  as illustrated in  FIG. 4 . In this case, from the far side and the right side of the gesture region  66  as viewed from the body trunk  60 A, an object other than the instructing body  70  will readily enter the gesture region  66 . Furthermore, from the near side of the gesture region  66 , the instructing body  70  that does not intend a gesture of an input instruction will readily enter the gesture region  66  due to a swing of a hand in normal walking or the like. Therefore, the setting unit  212  may set the gesture start preparation region  74  at the left end part of the gesture region  66  as illustrated in  FIG. 13 , for example. 
         [0085]    Furthermore, as illustrated in  FIG. 13 , the setting unit  212  sets at least a partial region in contact with the gesture region  66  as a gesture end region  76 . The gesture end region  76  is a region for determining the end of the gesture recognition by the detecting unit  213  when the instructing body  70  moves from the gesture region  66  to this region. For example, the setting unit  212  may set the gesture end region  76  around the gesture region  66  as illustrated in  FIG. 13 . 
         [0086]    For example, as illustrated in  FIG. 14 , parameters for setting each of the gesture start preparation region  74  and the gesture end region  76  are defined in addition to the parameters for setting the gesture region  66 . In the example of  FIG. 14 , it is defined that a region with a width S having the end part of the gesture region  66  on the side closer to the sensor 0 point as one side is employed as the gesture start preparation region  74 . Furthermore, it is defined that a region that is a region outside the gesture region  66  and corresponds to a margin E from the gesture region  66  is employed as the gesture end region  76 . 
         [0087]    In the case of using the parameters of  FIG. 14 , the setting unit  212  sets the gesture region  66  based on the parameters Th0, Th_a, Th_b, N, and F similarly to the setting unit  12  in the first embodiment. Furthermore, based on the set gesture region  66 , the setting unit  212  sets each of the gesture start preparation region  74  and the gesture end region  76  based on each of the parameters S and E. 
         [0088]    The detecting unit  213  detects, as the instructing body  70 , an object that passes through the gesture start preparation region  74  set by the setting unit  212  and enters the gesture region  66 . Then, the detecting unit  213  carries out gesture recognition regarding the detected instructing body  70  similarly to the detecting unit  13  in the first embodiment. Furthermore, the detecting unit  213  ends the recognition of a gesture and the detection of the instructing body  70  if the instructing body  70  moves from the gesture region  66  to the gesture end region  76 . 
         [0089]    For example, as illustrated in  FIG. 15 , if the position of an object represented by the measurement result makes time-series change of 1→2→3→4, the detecting unit  213  detects this object as the instructing body  70  and recognizes a gesture from time-series change in the detection result between 2 and 4. Furthermore, if change in the position of an object represented by the measurement result is 5→6→7, the detecting unit  213  does not detect this object as the instructing body  70  because the object does not pass through the gesture start preparation region  74  when entering the gesture region  66 . 
         [0090]    The detection device  210  included in the mounted equipment  16  may be implemented by the computer  40  illustrated in  FIG. 7 , for example. In the storing unit  43  of the computer  40 , a detection program  250  for causing the computer  40  to function as the detection device  210  is stored. The detection program  250  includes the acquisition process  51 , a setting process  252 , and a detection process  253 . 
         [0091]    The CPU  41  reads out the detection program  250  from the storing unit  43  and loads the detection program  250  into the memory  42  to sequentially execute the processes the detection program  250  has. The CPU  41  operates as the acquiring unit  11  illustrated in  FIG. 1  by executing the acquisition process  51 . Furthermore, the CPU  41  operates as the setting unit  212  illustrated in  FIG. 1  by executing the setting process  252 . Moreover, the CPU  41  operates as the detecting unit  213  illustrated in  FIG. 1  by executing the detection process  253 . This causes the computer  40  that executes the detection program  250  to function as the detection device  210 . 
         [0092]    It is also possible that functions implemented by the detection program  250  are implemented by a semiconductor integrated circuit for example, an ASIC or the like for more detail. 
         [0093]    Next, operation of the gesture input system  200  according to the second embodiment will be described. In the second embodiment, detection processing illustrated in  FIG. 16  is executed in the detection device  210 . Regarding the detection processing in the second embodiment, the processing similar to the detection processing ( FIG. 8 ) in the first embodiment is given the same numeral and detailed description of the processing is omitted. 
         [0094]    First, the steps S 11  to S 14  are carried out and the gesture region  66  is set in the measurement range  62 . Then, in the next step S 21 , the setting unit  212  sets the gesture start preparation region  74  and the gesture end region  76 . 
         [0095]    Next, in a step S 22 , the detecting unit  213  determines whether or not an object exists in the gesture start preparation region  74  based on the measurement result of the laser range scanner  17  and the gesture start preparation region  74  set in the above-described step S 21 . If an object exists in the gesture start preparation region  74 , the processing makes transition to a step S 23  and the detecting unit  213  sets a preparation flag F1 indicating that an object has entered the gesture start preparation region  74  to “ON,” and the processing returns to the step S 11 . 
         [0096]    On the other hand, if an object does not exist in the gesture start preparation region  74 , the processing makes transition to the step S 15  and the detecting unit  213  determines whether or not an object exists in the gesture region  66 . If an object exists in the gesture region  66 , the processing makes transition to a step S 24 . In the step S 24 , the detecting unit  213  sets a gesture region flag F2 indicating that an object exists in the gesture region  66  to “ON,” and the processing makes transition to a step S 25 . 
         [0097]    In the step S 25 , the detecting unit  213  determines whether or not the preparation flag F1 is “ON.” In the case of F1=“ON,” the preparation flag F1 indicates that the object has passed through the gesture start preparation region  74  and has entered the gesture region  66 . Therefore, the detecting unit  213  detects the object as the instructing body  70  that makes an input instruction and carries out gesture recognition in the subsequent steps S 16  to S 19 . On the other hand, in the case of F1≠“ON,” the preparation flag F1 indicates that the object has entered the gesture region  66  without passing through the gesture start preparation region  74 . Therefore, the detecting unit  213  regards the object as an object other than the instructing body  70  or the instructing body  70  that does not intend a gesture of an input instruction, and returns to the step S 11  without carrying out gesture recognition. 
         [0098]    Furthermore, if the negative determination is made in the step S 15 , the processing makes transition to a step S 26 . In the step S 26 , the detecting unit  213  determines whether or not an object exists in the gesture end region  76  based on the measurement result of the laser range scanner  17  and the gesture end region  76  set in the above-described step S 21 . If an object exists in the gesture end region  76 , the processing makes transition to a step S 27 . 
         [0099]    In the step S 27 , the detecting unit  213  determines whether or not the gesture region flag F2 is “ON.” In the case of F2=“ON,” the gesture region flag F2 indicates that the instructing body  70  that has existed in the gesture region  66  has moved to the gesture end region  76 , and it may be determined that the end of a gesture is intended. Therefore, the processing makes transition to a step S 28  and the detecting unit  213  sets both the flags F1 and F2 to “OFF.” Furthermore, in a step S 29 , the detecting unit  213  stops the vibrator  18  in actuation and the processing returns to the step S 11 . 
         [0100]    On the other hand, in the case of F2≠“ON,” the object has not moved from the gesture region  66  to the gesture end region  76  and recognition processing of a gesture is not currently being executed. Thus, the processing returns to the step S 11  without execution of the processing of the steps S 28  and S 29 . 
         [0101]    Furthermore, in the case of the negative determination in the step S 26 , the object as the processing target does not exist in the measurement range  62  and thus the processing returns to the step S 11 . 
         [0102]    As described above, according to the gesture input system  200  in accordance with the second embodiment, the detection device  210  included in the mounted equipment  16  sets the gesture start preparation region  74  adjacent to the gesture region  66 . Furthermore, the detection device  210  executes processing of gesture recognition regarding the instructing body  70  that has passed through the gesture start preparation region  74  and has entered the gesture region  66 . This may reduce processing of unnecessary gesture recognition in the case in which an object other than the instructing body  70  or the instructing body  70  that does not intend a gesture of an input instruction enters the gesture region  66 . 
       Third Embodiment 
       [0103]    Next, a third embodiment will be described. Regarding a gesture input system according to the third embodiment, the part similar to that of the gesture input system  100  according to the first embodiment is given the same numeral and detailed description of the part is omitted. 
         [0104]    As illustrated in  FIG. 17 , a gesture input system  300  according to the third embodiment includes mounted equipment  316 , the HMD  20 , and the server  30 . The mounted equipment  316  includes a detection device  310 , the laser range scanner  17 , and the vibrator  18 . The detection device  310  functionally includes an acquiring unit  311 , the setting unit  12 , the detecting unit  13 , and an environment recognizing unit  14 . 
         [0105]    The acquiring unit  311  accepts a measurement result output from the laser range scanner  17  and transfers the measurement result to the setting unit  12 . In addition, the acquiring unit  311  transfers the measurement result also to the environment recognizing unit  14 . 
         [0106]    The environment recognizing unit  14  recognizes the surrounding environment of the user  60  based on the measurement result of the laser range scanner  17 . For the environment recognition, measurement results of the whole of the measurement range  62  are used. Furthermore, if a hazardous place defined in advance is included in the recognized surrounding environment, the environment recognizing unit  14  vibrates the vibrator  18  in order to inform the user  60  of the existence of the hazardous place. 
         [0107]    As the hazardous places, a step in a floor, an obstacle existing in the traveling direction, and so forth are envisaged, for example. In the measurement result of the laser range scanner  17 , the shapes of objects existing in the surroundings may be recognized. Thus, patterns of the shapes representing the hazardous places are defined in advance. Furthermore, the environment recognizing unit  14  may detect the hazardous places by comparing the measurement result of the laser range scanner  17  and the patterns defined in advance. Moreover, for example, the value of the measurement result suddenly changes at a step part in a floor as illustrated in a part of an ellipse B in  FIG. 18 . Thus, the environment recognizing unit  14  may detect the hazardous places based on such a change in the value of the measurement result. 
         [0108]    The detection device  310  included in the mounted equipment  16  may be implemented by the computer  40  illustrated in  FIG. 7 , for example. In the storing unit  43  of the computer  40 , a detection program  350  for causing the computer  40  to function as the detection device  310  is stored. The detection program  350  includes an acquisition process  351 , the setting process  52 , the detection process  53 , and an environment recognition process  54 . 
         [0109]    The CPU  41  reads out the detection program  350  from the storing unit  43  and loads the detection program  350  into the memory  42  to sequentially execute the processes the detection program  350  has. The CPU  41  operates as the acquiring unit  311  illustrated in  FIG. 17  by executing the acquisition process  351 . Furthermore, the CPU  41  operates as the environment recognizing unit  14  illustrated in  FIG. 17  by executing the environment recognition process  54 . The other processes are similar to the detection program  50  according to the first embodiment. This causes the computer  40  that executes the detection program  350  to function as the detection device  310 . 
         [0110]    It is also possible that functions implemented by the detection program  350  are implemented by a semiconductor integrated circuit for example, an ASIC or the like for more detail. 
         [0111]    Next, operation of the gesture input system  300  according to the third embodiment will be described. In the third embodiment, in the detection device  310 , the detection processing similar to the detection processing ( FIG. 8 ) in the first embodiment is executed and environment recognition processing illustrated in  FIG. 19  is executed. 
         [0112]    First, in a step S 31 , the acquiring unit  311  accepts a measurement result output from the laser range scanner  17  and transfers the measurement result to the environment recognizing unit  14 . Next, in a step S 32 , the environment recognizing unit  14  recognize the surrounding environment of the user  60  based on the measurement result of the laser range scanner  17 . Next, in a step S 33 , the environment recognizing unit  14  determines whether or not a hazardous place defined in advance is included in the recognized surrounding environment. If a hazardous place is included in the surrounding environment, the processing makes transition to a step S 34  and the vibrator  18  is vibrated in order to inform the user  60  of the existence of the hazardous place. Then, the processing returns to the step S 31 . On the other hand, if a hazardous place is not included in the surrounding environment, the processing returns to the step S 31  without execution of the step S 34 . 
         [0113]    As described above, according to the gesture input system  300  in accordance with the third embodiment, the configuration used for gesture recognition may be used also for recognition of the surrounding environment of the user  60 . 
         [0114]    In the third embodiment, the case in which hazardous places are detected based on the recognized surrounding environment is described. However, the configuration is not limited to the case. For example, the surrounding environment recognized from a measurement result of the laser range scanner  17  may be collated with known environment data to estimate the position of the user  60  in the environment. 
         [0115]    Furthermore, in the third embodiment, an example of the detection device  310  obtained by adding the environment recognizing unit  14  to the detection device  10  according to the first embodiment is described. However, a configuration obtained by adding the environment recognizing unit  14  to the detection device  210  according to the second embodiment may be employed. 
         [0116]    Furthermore, in the above-described respective embodiments, the case in which the laser range scanner  17  of a plane scanning type is used is described. However, the configuration is not limited to the case. A laser range scanner of a three-dimensional scanning type that emits light while an emitting unit obtained by arranging plural light sources in the direction orthogonal to the scanning direction is scanned in the scanning direction may be used. In this case, the gesture region  66  may also be set as a three-dimensional region. 
         [0117]    In addition, in the above-described respective embodiments, the case of a hand part of the user  60  is described as one example of the instructing body  70  that makes an input instruction. However, the instructing body  70  may be another region of the user  60  such as a foot. Furthermore, if the user  60  makes gesture input while holding an instructing bar or the like, the instructing bar may be detected as the instructing body  70 . 
         [0118]    Moreover, in the above-described respective embodiments, the case in which the posture of a user  60  is estimated by using a measurement result of the laser range scanner  17  is described. However, the configuration is not limited to the case. A posture sensor consisting of an acceleration sensor, a gyro sensor, or the like may be mounted on the user  60  and the posture of the user  60  may be estimated based on a sensor value detected by the posture sensor. The posture sensor may be mounted on the user  60  separately from the mounted equipment  16  or a configuration in which the posture sensor is included in the mounted equipment  16  may be employed. 
         [0119]    Furthermore, in the above-described respective embodiments, the case in which the mounting position of the mounted equipment  16  is the body trunk  60 A (waist) of the user  60  is described. However, the mounted equipment  16  may be mounted on another region such as the head, the chest, or an arm. However, in the head, an arm, or the like, the flexibility in the region itself (movable range when the position of the user  60  is fixed) is high. Therefore, when the mounted equipment  16  is mounted, variation in the positional relationship between the mounted equipment  16  and the position at which the instructing body  70  makes a gesture (for example, position the right hand is able to reach) also becomes large. In the case of mounting the mounted equipment  16  on such a region having high flexibility, the gesture region  66  is set in consideration also of variation in the position at which the mounted equipment  16  is mounted. If the mounted equipment  16  is mounted on the body trunk  60 A as in the above-described embodiments, variation in the position at which the mounted equipment  16  is mounted is small and thus the instructing body  70  may be detected more stably. 
         [0120]    In the above-described respective embodiments, the modes in which the detection programs  50 ,  250 , and  350  are stored (installed) in the storing unit  43  in advance are described. However, the configuration is not limited to the modes. It is also possible to provide the detection programs according to the disclosed techniques in a form of being recorded on a recording medium such as a compact disc read-only memory (CD-ROM), a digital versatile disc (DVD)-ROM, or a universal serial bus (USB) memory. 
         [0121]    All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.