JP6015218B2 - Orientation detection device - Google Patents

Description

  The present disclosure relates to an azimuth detecting device capable of detecting an azimuth indicating a head direction of a moving body including a person.

  In order to obtain position information including the direction of the moving object with high accuracy by inertial navigation using an internal sensor including an acceleration sensor and an angular velocity sensor, drift included in the measurement values obtained by the acceleration sensor and angular velocity sensor is corrected. The technique to do is researched (refer nonpatent literature 1). For example, the technique of Non-Patent Document 1 combines position information obtained by inertial navigation technology with absolute position information obtained by GPS (Global Positioning System) or absolute angle information obtained by a geomagnetic sensor. The detection accuracy is improved.

  On the other hand, there is also proposed a technique for precisely detecting information indicating the position of a person by causing the person to carry a predetermined terminal device and detecting the terminal device (see Non-Patent Document 2).

Epson Toyocom_Sensing_System Design Summit 2010_Presentation Material, Nobuyuki Imai "Infrared voice information guidance system talking sign" Mitsubishi Precision Corporation [online], [searched on May 28, 2012], Internet <URL: http://www.techno-aids.or.jp/kaihatsu/j_42. shtml>

  By the way, since absolute position information by GPS cannot be used for detecting position information of a person staying indoors, depending on the technology combining GPS and inertial navigation, highly accurate position information can be obtained for a person moving indoors. It is difficult to do. Similarly, in facilities such as indoor exhibition halls, it is difficult to provide an absolute angle with respect to the earth's magnetic field using geomagnetic sensors because a local electromagnetic field is formed by a wide variety of equipment. is there. For this reason, it is difficult to accurately detect the moving direction of a person from the measurement value obtained by an angular velocity sensor such as a gyro sensor.

  On the other hand, according to the technique for specifying the position of a person by detecting the position of a predetermined terminal device possessed by the person, it is possible to specify the position of the person precisely, Information indicating the direction in which the person's head is facing cannot be acquired.

  An object of the present disclosure is to provide an azimuth detecting device that can detect the head direction of a moving body including a person with high accuracy.

An azimuth detecting device according to one aspect is a tracking unit that is mounted on a person's head and tracks an azimuth indicating the head direction of the person based on an angular velocity obtained by an angular velocity sensor that observes the rotational motion of the head. And a light projecting unit installed indoors that emits directional light in a predetermined direction, and is attached to the head of the person and is directed to incident light from the head direction of the person A light receiving unit that converts the incident light into an electrical signal and a direction in which light is emitted by the head direction of the person and the light projecting unit based on the electrical signal obtained by the light receiving unit. A detecting unit that detects a direct pairing with the light emitting direction; and a light emitting direction by the light projecting unit is detected when a direct pairing between the light emitting direction by the light projecting unit and the head direction of the person is detected. The corresponding first orientation is obtained by tracking the person's current And a setting unit that sets as a direction showing a head direction, the light projecting unit, a plurality of first light emitting element that emits light to different predetermined orientation to each other, said plurality of first light emitting element And a control unit that blinks in a pattern different from each other, and the detection unit is configured to select a head of the person from the plurality of first light emitting elements based on a temporal change in an electrical signal obtained by the light receiving unit. A specifying unit that specifies a first light emitting element that exists in a direction directly opposite to the partial direction, and the setting unit sets the light emission direction of the first light emitting element specified by the specifying unit as the first orientation. , Setting the direction indicating the current head direction of the person .

  According to the azimuth detecting device of the present disclosure, it is possible to detect the head direction of a moving body including a person with high accuracy.

It is a figure which shows one Embodiment of an azimuth | direction detection apparatus. It is a figure which shows the example of arrangement | positioning of a light projection part. It is a figure which shows the example of a direction detection result. It is a figure which shows another embodiment of a light projection part. It is a figure which shows another example of arrangement | positioning of a light projection part. It is a figure which shows one Embodiment of a light-receiving part. It is a figure explaining the directivity of a light-receiving part. It is a figure which shows another embodiment of an azimuth | direction detection apparatus. It is a figure explaining transmission / reception of a direction code. It is a figure which shows another embodiment of a light projection part. It is a figure which shows another embodiment of an azimuth | direction detection apparatus. It is a figure explaining transmission / reception of a direction code. It is a figure which shows another embodiment of a light projection part. It is a figure explaining transmission / reception of a direction code. It is a figure which shows the example of application of an azimuth | direction detection apparatus. It is a figure which shows another example of application of an azimuth | direction detection apparatus. It is a figure which shows embodiment of an information provision system. It is a figure which shows the hardware structural example of the information provision system containing an azimuth | direction detection apparatus. It is a figure which shows the hardware structural example of a portable terminal device and a headset. It is a figure which shows the example of the flowchart of an information provision process. It is a figure which shows the example of the flowchart of the process which detects the azimuth | direction which shows a head direction. It is a figure which shows the example of the flowchart of the process which detects the light projection part which faces directly.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an embodiment of an orientation detection device. The azimuth detecting device 10 shown in FIG. 1 includes a light receiving unit 13 and an angular velocity sensor Sa mounted on the head of a person P, and a light projecting unit 12 installed indoors.

  The angular velocity sensor Sa includes, for example, a gyro sensor, and measures an angular velocity when the head of the person P rotates. The light receiving unit 13 includes a photoelectric conversion element (not shown) that generates an electrical signal that reflects the intensity of incident light. The light receiving unit 13 is preferably attached to the person P so that the optical axis of the optical system that guides light to the photoelectric conversion element of the light receiving unit 13 matches the head direction of the person P. When the light receiving unit 13 is attached to the head of the person P in a preferable state, the light receiving sensitivity of the light receiving unit 13 is directed to incident light from the head direction of the person, which is a direction that matches the optical axis direction. Have sex. The light projecting unit 12 is installed near the ceiling at the corner of the room and emits light having directivity toward a predetermined direction. Note that a method for imparting directivity to the light receiving sensitivity of the light receiving unit 13 and a method for imparting directivity to the light emission direction by the light projecting unit 12 will be described later.

  In addition, the azimuth detection device 10 further includes a tracking unit 11, a detection unit 14, and a setting unit 15. The tracking unit 11 tracks the azimuth indicating the head direction of the person P based on the angular velocity obtained by the angular velocity sensor Sa. Based on the electrical signal obtained by the light receiving unit 13, the detection unit 14 detects the direct facing between the head direction of the person P and the emission direction in which light is emitted by the light projecting unit 12.

  As described above, the light emitted by the light projecting unit 12 and the light receiving sensitivity of the light receiving unit 13 each have directivity. Therefore, the light emitted from the light projecting unit 12 reaches the photoelectric conversion element of the light receiving unit 13 only when the light emitting direction of the light projecting unit 12 and the optical axis of the light receiving unit 13 are opposed to each other. . That is, the detection unit 14 indicates that the light from the light projecting unit 12 has reached the photoelectric conversion element of the light receiving unit 13 according to the electrical signal obtained by the light receiving unit 13 and the head direction of the person P. The direct alignment with the light emission direction by the light projecting unit 12 is detected. FIG. 1 shows a state in which the light emission direction by the light projecting unit 12 and the optical axis of the light receiving unit 13 face each other. At this time, the head direction of the person P coincides with the light emission direction by the light projecting unit 12. Moreover, the light emission direction by the light projecting unit 12 can be obtained in advance as an absolute angle as a reference such as a wall of a room, for example.

  In other words, the head direction of the person P when the detection unit 14 detects a direct alignment with the light emission direction by the light projecting unit 12 is an absolute angle corresponding to the light emission direction by the light projection unit 12. Can be shown.

  The setting unit 15 corresponds to the light emitting direction by the light projecting unit 12 when the detecting unit 14 detects the direct alignment between the light emitting direction by the light projecting unit 12 and the head direction of the person P. One direction is set as a reference for tracking the direction by the tracking unit 11. For example, the setting unit 15 obtains in advance a first azimuth indicating the light emission direction by the light projecting unit 12, and sets the azimuth obtained by the tracking processing by the tracking unit 11 according to the detection result by the detection unit 14. It may be replaced with one direction.

  FIG. 2 shows an arrangement example of the light projecting unit 12. 2 that are the same as those shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In the example of FIG. 2, the light projecting unit 12 is installed at one corner R of the room C, and emits light in a direction from the wall W of the room C in the clockwise direction toward the center of the room C by an angle φ0. Is installed.

  FIG. 2 shows a state where a person P moving in the room C has his head directed to a corner R of the room C where the light projecting unit 12 is installed. At this time, the light from the light projecting unit 12 is incident on the light receiving unit 13, and the detection unit 14 illustrated in FIG. 1 projects the light from the head direction of the person P according to the electrical signal obtained by the light receiving unit 13. The direct facing of the light emission direction by the unit 12 is detected.

  As shown in FIG. 2, when the person P points his head to the corner R of the room C, the direction indicating the head direction of the person P is determined by the light emission direction of the light projecting unit 12 and the wall W. It is possible to specify absolutely based on the formed angle φ0.

  For example, when the head direction of the person P is expressed with reference to the direction in which the wall W is installed, the setting unit 15 illustrated in FIG. 1 may use, for example, the above-described angle φ0 as the first orientation as it is. . Further, when the detection unit 14 detects the direct facing of the light emission direction by the light projecting unit 12, the setting unit 15 acquires the tracking unit 11 illustrated in FIG. 1 through tracking processing using inertial navigation technology. The azimuth is reset to the angle φ0 described above. Thereby, the error due to drift accumulated in the estimation result of the head direction of the person P can be eliminated in the course of the tracking process so far. Further, the tracking unit 11 continues the azimuth tracking process based on the angular velocity data obtained thereafter by the angular velocity sensor Sa shown in FIG. 1 with the angle φ0 set by the setting unit 15 as a reference.

  That is, according to the azimuth detecting device 10 shown in FIG. 1, every time the person P1 turns his head toward the projector 12, the tracking result about the azimuth indicating the head direction of the person P1 obtained by the tracking unit 11 is described above. Reset to the first orientation. Thus, every time the person P1 points the head to the projector 12, the error accumulated in the direction obtained by the inertial navigation technique can be eliminated, so that the head direction of the person P obtained by the tracking unit 11 is shown. The direction accuracy can be improved.

  FIG. 3 shows an example of the direction detection result obtained by the direction detection device 10. In FIG. 3, the horizontal axis t indicates the passage of time, and the vertical axis θ indicates the angle with reference to the wall W shown in FIG.

  A symbol G0 illustrated in FIG. 3 is an example of a graph representing a change with time t of the azimuth θ indicating the actual head direction of the person P illustrated in FIG. Further, reference symbol Gd is an example of a graph representing a change with time t of the azimuth θ obtained by the tracking unit 11 using the inertial navigation technique based on the angular velocity obtained by the angular velocity sensor Sa shown in FIG. .

  Comparing the graph G0 and the graph Gd, it can be seen that the divergence between the azimuth θ obtained by the tracking unit 11 and the azimuth θ indicating the head direction of the person P increases with time.

  On the other hand, the symbol G1 illustrated in FIG. 3 is an example of a graph representing a change with time t of the azimuth θ indicating the head direction of the person P obtained by the azimuth detection device 10 of the present disclosure. The example of the graph G1 shown in FIG. 3 shows a case where the setting unit 15 shown in FIG. 1 resets the azimuth θ obtained by the tracking unit 11 using the first azimuth φ0 described above at time T1 and time T2. Show. Times T1 and T2 correspond to times when the person P turns his head toward the light projecting unit 12 installed in the room C shown in FIG.

  As shown in FIG. 3, the divergence between the azimuth θ represented by the graph G0 and the azimuth θ represented by the graph G1 is eliminated every time the tracking result of the tracking unit 11 is reset by the first azimuth φ0. ing. That is, during the period in which the person P1 does not turn his head toward the light projecting unit 12, the error that has increased due to accumulation of drift components included in the angular velocity data obtained by the angular velocity sensor Sa is displayed on the light projecting unit 12. Each time you turn your head, you can clear it.

  Here, in the process in which the person P moves freely in the room C shown in FIG. 2, the head of the person P is directed toward the light projecting unit 12 when the person P looks around. There is a possibility that. And the error contained in the detection result by the azimuth | direction detection apparatus 10 can be suppressed by clearing the error accumulate | stored so far every time the person P turns the head in the direction of the light projection part 12. FIG.

  Thus, according to the azimuth detecting device 10 disclosed herein, the azimuth indicating the head direction can be obtained with higher accuracy than in the case where the head direction of the person P is tracked using the conventional inertial navigation technique. Can do.

  Furthermore, by increasing the chance of resetting the direction obtained by the tracking process using the inertial navigation technology, the detection accuracy of the direction indicating the head direction of the person P by the direction detection device 10 of the present disclosure can be further improved. it can. Below, an example of the method for improving the detection accuracy of the azimuth | direction detection apparatus 10 is demonstrated.

  FIG. 4 shows another embodiment of the light projecting unit 12. 4 that are the same as those shown in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

  The light projecting unit 12 shown in FIG. 4 includes five LEDs (Light Emitting Diodes) 1, LED 2, LED 3, LED 4, and LED 5 that can be turned on and off independently. These LEDs 1 to 5 are an example of a plurality of first light emitting elements included in the light projecting unit 12. Moreover, each LED1-LED5 is arrange | positioned so that light may be inject | emitted in a different direction inside the light projection part 12, respectively. In FIG. 4, the symbol Ze <b> 1 indicates the light emission direction of the LED 1, and the symbol α <b> 1 indicates the range in which the light emitted from the LED 1 is dispersed. Symbol Ze2 indicates the light emission direction of the LED 2, and symbol α2 indicates the range in which the light emitted from the LED 2 is dispersed. Similarly, the symbol Ze3 indicates the light emission direction of the LED 3, and the symbol α3 indicates the range in which the light emitted from the LED 3 is dispersed. Similarly, the symbol Ze4 indicates the light emission direction of the LED 4, and the symbol α4 indicates a range in which the light emitted from the LED 4 is dispersed. The symbol Ze5 indicates the direction of light emission from the LED 5, and the symbol α5 indicates the range in which the light emitted from the LED 5 is dispersed.

  Further, reference signs θ1, θ2, θ3, θ4, and θ5 illustrated in FIG. 4 indicate the azimuths of the light emission directions of the LEDs 1 to 5 with respect to the wall W of the room C. That is, the azimuths θ1 to θ5 illustrated in FIG. 4 are examples of the first azimuth indicating the light emission directions of the LEDs 1 to LED5 included in the light projecting unit 12, respectively. In addition, it is desirable that the LEDs 1 to 5 shown in FIG. 4 are positioned inside the light projecting unit 12 so that the emission directions Ze1 to Ze5 are different from each other by several degrees. For example, when five LEDs 1 to 5 are arranged in different emission directions by 6 degrees from each other, the light projecting section 12 in FIG. 4 emits light beams each having a directivity in a range of 30 degrees. be able to.

  Moreover, the azimuth | direction (theta) 1- (theta) 5 which shows the emission direction of the light corresponding to each LED1-LED5 shown in FIG. 4 can be represented by blinking each LED1-LED5 with a respectively different pattern. For example, each LED1 to LED5 may be blinked in a pattern representing an orientation code indicating an orientation corresponding to each emission direction Ze1 to Ze5. In this case, the blinking pattern of the light incident on the light receiving unit 13 shown in FIG. 4 indicates an azimuth code representing the azimuth θ3 corresponding to the emission direction Ze3 facing the optical axis direction of the light receiving unit 13. . That is, it is possible to specify the direction indicating the incident direction of the light incident on the light receiving unit 13 based on the blinking pattern of the incident light reflected in the electrical signal obtained by the light receiving unit 13.

  According to the azimuth detecting apparatus 10 having the light projecting unit 12 as shown in FIG. 4, if the head direction Q of the person P is included in any of the above-described ranges α1 to α5, the individual ranges α1 to α1. The tracking result can be reset using the first direction corresponding to α5. For example, in the example of FIG. 4, since the blinking light is incident on the light receiving unit 13 in a pattern representing the azimuth θ3, the azimuth detecting device 10 resets the tracking result using the azimuth θ3 as the first azimuth.

  Further, a plurality of light projecting units 12 shown in FIG. 4 may be installed together. In the following description, a component including a plurality of light projecting units 12 including a plurality of LEDs described above is referred to as an anchor unit AU.

  FIG. 5 shows another example of the arrangement of the light projecting unit 12. 5 that are the same as those shown in FIG. 1 or FIG. 2 are given the same reference numerals, and descriptions thereof are omitted. 5 indicate examples of positions where the person P wearing the light receiving unit 13 may stay inside the room C.

  The anchor unit AU illustrated in FIG. 5 includes three light projecting units 12-1, 12-2, and 12-3. The three light projecting units 12-1, 12-2, and 12-3 are positioned in the anchor unit AU so that the ranges where the light from the LEDs included in the respective light projecting units do not overlap each other. Each of the light projecting units 12-1, 12-2, and 12-3 has the same configuration as the light projecting unit 12 shown in FIG.

  In the example of FIG. 5, the ranges α <b> 1 to α <b> 5 (see FIG. 4) in which light emitted from the respective LEDs included in each of the light projecting units 12-1, 12-2, and 12-3 are about 6 degrees in the horizontal direction. The case where it has a spread is shown. In this case, the angle range corresponding to the light projecting unit 12 illustrated in FIG. 4 is 30 degrees, and the angle range corresponding to the anchor unit AU including the three light projecting units 12-1, 12-2, and 12-3 is set. The range is 90 degrees. Further, the LEDs included in the anchor units AU1 and AU2 can be distinguished from each other from the light receiving unit 13 side by blinking in a pattern representing a direction code indicating the emission direction of each light. Note that a method for specifying the LED from which light is incident on the light receiving unit 13 will be described later with reference to FIGS. 8 and 9.

  By installing the anchor unit AU illustrated in FIG. 5 at one corner R of the room C, the person P points his head to the corner R of the room C regardless of the position of the person P inside the room C. The orientation detection result described above can be reset.

  For example, in the example of FIG. 5, when the person P turns his head toward the corner R of the room C from the position indicated by the reference sign P <b> 1, the head direction of the person P and the LEDs included in the light projecting unit 12-2 The light emission direction by either is directly facing. In this case, the tracking result of the head direction of the person P is θa corresponding to the light emission direction of the LED that is incident on the light receiving unit 13 among the LEDs included in the light projecting unit 12-1. To reset.

  Further, in the example of FIG. 5, when the person P at the position indicated by the reference sign P2 points his head to the corner R of the room C, the head direction of the person P and the LEDs included in the light projecting unit 12-1. The light emission direction by any of the above is directly opposed. In this case, the tracking result of the head direction of the person P is the first corresponding to the light emission direction of the LED that is incident on the light receiving unit 13 among the LEDs included in the light projecting unit 12-1. It is reset using the azimuth θb.

  A plurality of anchor units AU may be installed in the room C. For example, by arranging the anchor units AU shown in FIG. 5 at the four corners of the room C, the probability that the anchor units AU are captured in the field of view of the persons P1 and P2 staying in the room C is increased, and the above-described orientation detection is performed. Opportunities for resetting the results can be further increased. As described above, every time the azimuth detection result is reset, the error included in the azimuth obtained as a detection result by the azimuth detection device 10 disclosed herein is cleared. Therefore, the error included in the azimuth | direction obtained by the azimuth | direction detection apparatus 10 of this indication can be reduced, so that the opportunity which resets a azimuth | direction detection result increases.

  Next, a method for realizing desired directivity in the light receiving unit 13 attached to the head of the person P will be described with reference to FIGS. 6 and 7.

  FIG. 6 shows an embodiment of the light receiving unit 13. In FIG. 6, symbol Zi indicates the optical axis of the optical system included in the light receiving unit 13. In the example of FIG. 6, the optical axis Zi and the head direction Q of the person P coincide with each other. Further, the X axis shown in FIG. 6 indicates the horizontal direction orthogonal to the direction of gravity acceleration, and the Y axis indicates the vertical direction that matches the direction of gravity acceleration.

  The light receiving unit 13 illustrated in FIG. 6 includes a photoelectric conversion element 131, a mask 132, a linear Fresnel lens 133, and a slit plate 134. The photoelectric conversion element 131 generates an electrical signal reflecting the intensity change of incident light and passes it to the detection unit 14 shown in FIG. The mask 132 is disposed on the light incident side of the photoelectric conversion element 131 and has an opening having a smaller width in the horizontal direction than the length in the vertical direction. The linear Fresnel lens 133 has refractive power only in the horizontal direction. The slit plate 134 has a slit whose longitudinal direction is the longitudinal direction, like the opening of the mask 132 described above. Further, it is desirable that the optical axis of the optical system including the linear Fresnel lens 133 and the slit plate 134 is positioned so as to be perpendicular to the light receiving surface of the photoelectric conversion element 131.

  The linear Fresnel lens 133 focuses a light beam that has passed through a slit provided in the slit plate 134 in the horizontal direction, thereby forming a linear image extending in the Y-axis direction at the opening of the mask 132 described above.

  Here, the position of the linear image formed by the linear Fresnel lens 133 in the X-axis direction depends on the angle formed between the light beam incident on the light receiving unit 13 and the optical axis Zi, as shown in FIG.

  FIG. 7 is a diagram illustrating the directivity of the light receiving unit 13. Note that among the elements shown in FIG. 7, elements equivalent to those shown in FIG. 6 are denoted by the same reference numerals and description thereof is omitted.

  In FIG. 7, reference sign Ray <b> 1 indicated by a solid line indicates a light beam incident on the linear Fresnel lens 133 from the direction parallel to the optical axis Zi through the slit 134. On the other hand, in FIG. 7, reference numeral Ray <b> 2 indicated by a dotted line indicates a light beam obliquely incident on the linear Fresnel lens 133 through the slit plate 134 from the direction intersecting the optical axis Zi. In addition, the code | symbol (beta) shown in FIG. 7 has shown the angle which the optical axis Zi and the light beam Ray2 make. In FIG. 7, the symbol d indicates the width of the opening received by the mask 132, and the symbol f indicates the focal length of the linear Fresnel lens 133.

  In the example of FIG. 7, the light beam Ray <b> 1 is imaged inside the opening of the mask 132 by the linear Fresnel lens 133. Therefore, since the light beam Ray1 is incident on the photoelectric conversion element 133, an electric signal corresponding to the intensity of the light beam Ray1 is generated by the photoelectric conversion element 133.

  On the other hand, in the example of FIG. 7, the light beam Ray <b> 2 is imaged outside the opening of the mask 132 by the linear Fresnel lens 133. For this reason, the light beam Ray2 does not enter the photoelectric conversion element 133. Therefore, the photoelectric conversion element 133 does not generate an electric signal corresponding to the intensity of the light beam Ray2.

  Therefore, according to the light receiving unit 13 shown in FIGS. 6 and 7, only when light is incident from a direction intersecting the optical axis Zi at an angle shallower than the angle β described above, the light passes through the opening of the mask 132. Thus, an electrical signal corresponding to the light incident on the photoelectric conversion element 131 is obtained.

  That is, according to the optical system including the linear Fresnel lens 133 and the mask 132 as shown in FIGS. 6 and 7, the direction in which the light receiving unit 13 has sensitivity is centered on the optical axis Zi, and the horizontal plane by the angle β described above. The range can be limited to a range γ in which the upper and lower limits of the rotation angle are indicated. That is, by providing the above-described optical system, the light receiving unit 13 having high directivity with respect to the direction of the optical axis Zi can be realized. Further, the high directivity of the light receiving unit 13 can be adjusted by the relationship between the focal length f of the linear Fresnel lens 133 and the width d of the opening of the mask 132. For example, the angle corresponding to the dispersion range of the light emission direction by each LED included in the light projecting unit 12 shown in FIG. 4 is adjusted to match the angle corresponding to the range γ shown in FIG. Can do. For example, when a linear Fresnel lens 133 having a focal length of 6 millimeters is used, if the width d of the opening of the mask 132 is 0.5 millimeters, the angle corresponding to the above range γ can be set to about 5 degrees. Is possible.

  The linear Fresnel lens 133 as shown in FIGS. 6 and 7 forms an image of a light beam incident at a predetermined range around the optical axis Zi on the opening of the mask 132 and is incident at an angle exceeding the predetermined range. 2 is an example of an imaging optical system that forms an image of the luminous flux to be formed outside the opening of the mask 132. FIG. As described above, the range γ in which a linear image is formed on the opening of the mask 132 by the linear Fresnel lens 133 is related to the light emission direction of each LED included in the light projecting unit 12 shown in FIG. It is desirable to adjust to be equal to each of the dispersion ranges α1 to α5. The optical element used in the imaging optical system provided in the light receiving unit 13 is not limited to the linear Fresnel lens 133 described above. For example, an optical element having a refractive power larger than the other in one direction of the coordinate axis orthogonal to the optical axis, such as a cylindrical lens, may be used as the imaging optical system of the light receiving unit 13.

  The light receiving unit 13 shown in FIGS. 6 and 7 has high directivity with respect to the horizontal component in the incident direction, and has sensitivity over a wide range with respect to the vertical component. For this reason, the azimuth detecting device 10 including the light receiving unit 13 illustrated in FIGS. 6 and 7 has high resolution with respect to changes in the head direction accompanying rotation about the vertical axis of the head of the person P, There is no resolution for the elevation angle component or depression component in the head direction.

  The above-described characteristics of the light receiving unit 13 illustrated in FIGS. 6 and 7 include, for example, information on an object specified by a position on a horizontal plane based on the head direction of the person P obtained by the direction detection device 10. Suitable for applications to be provided. Because if the object to be provided information can be specified at the position on the horizontal plane, the target is specified based only on the rotation component in the horizontal plane in the head direction, regardless of the elevation angle component or depression angle component in the head direction. Because it is possible.

  Further, by identifying the difference between the elevation angle component and the depression angle component in the head direction without distinguishing between them, the opportunity to detect the right-to-face detection between the head direction and any of the LEDs included in the light projecting unit 12 is increased. be able to. Further, the optical system of the light receiving unit 13 shown in FIGS. 6 and 7 can be realized using, for example, an optical element as small as a button battery. Very useful.

  An example of the object that can be specified by the position on the horizontal plane is, for example, the position of each booth arranged in the exhibition hall. A method for realizing a system for providing information related to each booth in an exhibition hall or the like using the azimuth detecting device 10 of the present disclosure will be described later with reference to FIGS.

  Next, an embodiment of the azimuth detecting device 10 that is suitable when the anchor unit AU in which the light projecting unit 12 and the plurality of light projecting units 12 are integrated as shown in FIG. 4 is installed at a plurality of locations in the room will be described.

  FIG. 8 shows another embodiment of the direction detection device 10. 8 that are the same as those shown in FIG. 1 or FIG. 4 are denoted by the same reference numerals, and the description thereof is omitted.

  The azimuth detecting device 10 shown in FIG. 8 includes n light projecting units 12-1,..., 12-n, and an azimuth table 122 that can be referred to from these light projecting units 12-1,. Is included. The light projecting unit 12-1 includes five LEDs 1, LED2, LED3, LED4, and LED5, and a control unit 121 that controls turning on and off of the LEDs 1 to LED5. In addition, although illustration is abbreviate | omitted in FIG. 8, n light projection part 12-1, ..., 12-n is five LED, a control part, and the same as the light projection part 12-1 mentioned above. Is included. In the following description, when the n light projecting units 12-1,..., 12-n are not distinguished from each other, they are simply referred to as the light projecting unit 12.

  The azimuth table 122 holds, for example, an azimuth code indicating an absolute angle measured from a predetermined reference as information indicating an emission direction of light from the LED corresponding to an identification number indicating each LED. ing. In addition, as an absolute angle indicating the light emission direction of each LED, for example, as shown in FIG. 2, a value measured with reference to the direction of the wall W of the room C where the light projecting unit 12 is installed is used. It may be adopted. In addition, the control unit 121 included in each light projecting unit 12 receives a direction code corresponding to each of the five LEDs included in the light projecting unit 12 from the direction table 122, and the corresponding LED based on the received direction code. Control to blink each.

  For example, the control unit 121 may transmit the direction codes corresponding to the LEDs 1 to LED5 in a time-sharing manner by blinking five LEDs 1, LED2, LED3, LED4, and LED5 in accordance with the corresponding direction codes.

  FIG. 9 shows a diagram for explaining transmission / reception of a direction code. In FIG. 9, each of the codes Cord1, Cord2, Cord3, Cord4, Cord5 indicates an orientation code corresponding to LED1, LED2, LED3, LED4, LED5 shown in FIG.

  FIG. 9A shows a state in which each LED1 to LED5 blinks in a time-sharing manner according to the control by the control unit 121 shown in FIG. 8 to transmit the corresponding direction code Cord1, Cord2, Cord3, Cord4, Cord5. Is shown.

  FIGS. 9B and 9C show electric signals generated by the light receiving unit 13 when light emitted from at least one of the LEDs 1 to 5 described above is incident on the light receiving unit 13 shown in FIG. An example is shown.

  The example in FIG. 9B indicates that an electric signal indicating the orientation code Cord3 corresponding to the LED 3 is acquired when the light emitted by the LED 3 enters the light receiving unit 13. That is, the example of FIG. 9B is generated by the light receiving unit 13 when the range α3 shown in FIG. 4 corresponding to the LED 3 and the range γ shown in FIG. It is an example of the electric signal to be performed.

  In the example of FIG. 9C, the light emitted from the LED 3 and the LED 4 is incident on the light receiving unit 13, thereby indicating both the direction code Cord 3 corresponding to the LED 3 and the direction code Cord 4 corresponding to the LED 4. It shows that the signals are acquired sequentially. In the example of FIG. 9C, when a part of the ranges α3 and α4 shown in FIG. 4 corresponding to the LEDs 3 and 4 is included in the range γ shown in FIG. 4 is an example of an electrical signal generated by a unit 13.

  The signal processing unit 141 included in the detection unit 14 illustrated in FIG. 8 receives the electrical signal generated by the light receiving unit 13 and converts the received electrical signal into a digital signal. The detection unit 14 illustrated in FIG. 8 further includes a specifying unit 142 having a matching unit 143 and a code table 144.

  The code table 144 holds, for example, a bit pattern indicating all azimuth codes that may be transmitted by blinking of the LEDs included in the light projecting units 12-1 to 12-n. The collation unit 143 collates the digital signal obtained by the signal processing unit 141 with each bit pattern held in the code table 144, so that the direction code indicated by the intensity change of the light beam incident on the light receiving unit 13 is obtained. Is identified.

  Here, since the direction code and the LED included in the light projecting unit 12 correspond one-to-one, the specification of the direction code is equivalent to the specification of the LED. The orientation code specified by the collation unit 143 indicates an absolute angle indicating the incident direction of light to the light receiving unit 13. Therefore, when only one azimuth code is specified by the collation unit 143, the setting unit 15 uses the azimuth code as it is and replaces the tracking result obtained by the tracking unit 11 to thereby obtain the above azimuth detection result. May be reset.

  On the other hand, as in the example shown in FIG. 9C, the light receiving unit 13 may generate electrical signals corresponding to two azimuth codes. In such a case, in order to reset the azimuth detection result based on the two azimuth codes specified by the collation unit 143, the setting unit 15 illustrated in FIG. 8 includes the determination unit 151 and the calculation unit 152. Contains.

  The determination unit 151 determines whether there is one or two azimuth codes specified by the collation unit 143. If there is one, the tracking unit 11 uses the specified azimuth code as it is. A process for replacing the obtained tracking result is executed. When the determination unit 151 determines that there are two azimuth codes specified by the collation unit, the calculation unit 152 receives two azimuth codes via the determination unit 151. Further, the calculation unit 152 calculates an azimuth indicating the optical axis direction of the light receiving unit 13, that is, the head direction of the person P, based on the received two azimuth codes. For example, the calculation unit 152 may calculate an average value of absolute angles indicated by two azimuth codes, and execute a process of replacing the tracking result obtained by the tracking unit 11 using the calculated average value. Good.

  According to the setting unit 15 having the calculation unit 152 illustrated in FIG. 8, the tracking unit 11 tracks with a resolution higher than the resolution determined by the dispersion range in the light emission direction of each LED included in the light projecting unit 12. The absolute angle for resetting the result can be determined. Thereby, the gap between the tracking result reset by the setting unit 15 and the head direction of the person P can be further reduced. Therefore, according to the azimuth detecting device 10 having the setting unit 15 shown in FIG. 8, it is possible to detect the head direction of the person P with higher accuracy.

  By the way, the method of transmitting the direction code indicating the light emission direction of each LED included in the light projecting unit 12 to the light receiving unit 13 is not limited to the method of expressing the direction code itself by blinking of each LED. For example, as will be described below, the light emission direction of each LED is determined by a combination of identification information given to each light projecting unit 12 and information identifying each LED included in the light projecting unit 12. The information shown may be transmitted to the light receiving unit 13.

  FIG. 10 shows another embodiment of the light projecting unit 12. Note that, among the components shown in FIG. 10, components equivalent to those shown in FIG. 4 are denoted by the same reference numerals and description thereof is omitted.

  The light projecting unit 12 illustrated in FIG. 10 includes a dispersion range α1 to α5 in the light emission direction of the LEDs 1 to LED5 separately from the LEDs 1 to LED5 to which high directivity is provided as an example of the first light emitting element. LED0 is included as a 2nd light emitting element which irradiates light to (alpha) 0.

  The identification information given to each light projecting unit 12 can be indicated by blinking the LED 0 shown in FIG. 10 according to the identification information. Further, the information for identifying the five LEDs 1 to 5 included in FIG. 10 may be indicated by the order in which each of the LEDs 1 to 5 is emitted.

  FIG. 11 shows another embodiment of the azimuth detecting device 10 suitable for the case where the light projecting unit 12 shown in FIG. 10 is employed. Note that among the components shown in FIG. 11, components equivalent to those shown in FIGS. 8 and 10 are denoted by the same reference numerals, and description thereof is omitted.

  The light projecting unit 12-1 illustrated in FIG. 11 is provided to the light projecting unit 12-1 together with the LEDs 0 to LED5 illustrated in FIG. 10 and the control unit 121 that controls turning on and off of the LEDs 0 to LED5. ID (IDentifier) holding unit 123 that holds the identification information. Note that each of the n light projecting units 12-1 to 12-n included in the azimuth detecting device 10 illustrated in FIG. 11 is controlled with LED0 to LED5 in the same manner as the light projecting unit 12-1. Part 121 and an ID holding part 123 are included. Moreover, when naming each light projection part 12-1 to 12-n generically, it will only be called the light projection part 12. Similarly, when LED0 to LED5 are collectively referred to, they are simply referred to as LEDs.

  The control unit 121 performs, for example, time-sharing control for causing the LED 0 to blink according to the identification information held in the ID holding unit 123 and control for sequentially emitting the LEDs 1 to 5 that emit light having directivity. According to the light projecting unit 12 including the control unit 121 that performs the above-described control, the identification information indicating the individual light projecting units 12 and the information identifying each of the LEDs 1 to 5 included in the light projecting unit 12 are time-shared. Can be sent.

  FIG. 12 is a diagram for explaining transmission / reception of a direction code. In FIG. 12, the code Cord0 indicates identification information given to the light projecting unit 12 indicated by the blinking pattern of the LED0. In FIG. 12, reference numerals L1, L2, L3, L4, and L5 indicate periods in which LED1, LED2, LED3, LED4, and LED5 are lit, respectively.

  FIG. 12A includes the identification information indicating each light projecting unit 12 and the light projecting unit 12 by controlling the light emission of the LED 0 and the LEDs 1 to 5 by the control unit 121 illustrated in FIG. The information which identifies each LED1-LED5 to be transmitted by the time division is shown.

  In the example of FIG. 12A, there are a period in which LED0 blinks in accordance with the identification information Cord0 and a period in which LEDs 1 to LED5 emit light for a period of time equal to or less than the predetermined time τ described above at different timings τ. It appears alternately. In the example of FIG. 12A, the LEDs 1 to 5 emit light sequentially by time τ during a period in which information for identifying each of the LEDs 1 to 5 included in the light projecting unit 12 is transmitted.

12B and 12C are generated by the light receiving unit 13 when light emitted from at least one of the above-described LEDs 1 to 5 is incident on the light receiving unit 13 illustrated in FIG. An example of an electrical signal is shown. In FIGS. 12B and 12C, code Cord0 indicates an electric signal indicating identification information Cord0. The symbol ts indicates the time from the beginning of the electrical signal indicating the identification information Cord0 to the rise of the pulse signal corresponding to the incidence of light from at least one of the LEDs 1 to 5 having directivity. The symbol te indicates the time from the beginning of the electrical signal indicating the identification information Cord0 to the fall of the pulse signal described above. In the example of FIG. 12B, the light emitted from the LED 2 is received by the light receiving unit 13. In addition to the electric signal indicating the identification information Cord0 described above, the light receiving unit 13 generates the pulse signal L2 at a timing corresponding to the LED2. That is, the example in FIG. 12B is generated by the light receiving unit 13 when the range α2 shown in FIG. 10 corresponding to the LED 2 and the range γ shown in FIG. It is an example of the electric signal to be performed.

  In the example shown in FIG. 12B, the time ts until the rise of the pulse signal is the sum (T0 + τ) of the duration T0 of the electrical signal indicating the identification information Cord0 and the emission time τ of the LED 1 that emits light prior to the LED2. ). Further, the time te until the fall of the pulse signal described above corresponds to the sum (T0 + 2τ) of the time ts until the rise of the pulse signal and the light emission time of the LED 2.

  The example of FIG. 12C shows an example of an electrical signal obtained by the light receiving unit 13 when both the light emitted from the LEDs 3 and 4 enters the light receiving unit 13. In this case, the electrical signal obtained by the light receiving unit 13 includes pulse signals L3 and L4 at timings corresponding to the LEDs 3 and 4 together with the electrical signal indicating the identification information Cord0.

  In the example shown in FIG. 12C, the time ts until the rise of the pulse signal is the duration T0 of the electric signal indicating the identification information Cord0, the light emission time τ of the LED 1 that emits light prior to the LED 3, and the light emission time of the LED 2. This corresponds to the sum (T0 + 2τ) with τ. The above-described time te until the falling edge of the pulse signal corresponds to the sum (T0 + 4τ) of the time ts until the rising edge of the pulse signal, the light emission time τ of the LED 3 and the light emission time τ of the LED 4.

  The detection unit 14 illustrated in FIG. 11 performs extraction in order to identify the LED that is the emission source of the light incident on the light receiving unit 13 based on the electrical signals illustrated in FIGS. A specifying unit 142 including a unit 145 and a determination unit 146 is included.

  The extraction unit 145 extracts the identification information Cord0 transmitted from the LED0 described above from the digital signal received from the signal processing unit 141. In addition, the extraction unit 145 passes the extracted identification information Cord0 to the setting unit 15 as information indicating the light projecting unit 12 including the LED that has emitted the light incident on the light receiving unit 13.

  On the other hand, the determination unit 146 first measures the time ts from the beginning of the identification information Cord0 extracted by the extraction unit 145 to the rise of the pulse signal and the time te until the fall. Moreover, the discrimination | determination part 146 specifies the light emission order in the light projection part 12 containing the said LED about the LED which inject | emitted the light which injected into the light-receiving part 13 based on time ts and te obtained by measurement, The LED is determined.

  For example, the determination unit 146 compares the difference between the time ts obtained by the measurement and the above-described time T0 and the light emission time τ, so that the early light emission order of the LEDs emitting the light incident on the light receiving unit 13 is increased. The light emission order corresponding to the given LED may be specified. In addition, when the difference between the time te and the time ts obtained by measurement is the light emission time τ, the determination unit 146 specifies information indicating the light emission order of the LEDs specified based on the time ts by the specification unit 142. Output as a result. On the other hand, when the difference between the time te and the time ts obtained by measurement is twice the light emission time τ, the determination unit 146 determines that the light emitted by the two LEDs is incident on the light receiving unit 13. Judge that it has reached. In this case, the determination unit 146 outputs information indicating the light emission order of the LEDs specified based on the time ts as well as information indicating the next light emission order corresponding to the light emission order as a specification result by the specification unit 142.

  For example, in the example shown in FIG. 12B, since the difference between the time ts until the rise of the pulse signal and the time T0 corresponds to the light emission time τ, the light source of the light reaching the light receiving unit 13 is projected. It can be seen that the LED 2 emits the second light in the portion 12. In this case, the determination unit 146 uses the information indicating the light emission order “2” of the LED 2 as information indicating the first light emitting element present in the direction facing the head direction of the person P, and the setting unit illustrated in FIG. Pass to 15.

  On the other hand, in the example shown in FIG. 12C, the difference between the time ts until the rise of the pulse signal and the time T0 corresponds to twice the light emission time τ. One shows that the LED 3 emits light third in the light projecting unit 12. Since the difference between the time ts until the rise of the pulse signal ts and the time te until the fall corresponds to twice the light emission time τ, the light emitted by the LED 4 that emits light following the LED 3 is also received by the light receiving unit. It can be seen that 13 has been reached. In this case, the determination unit 146 displays information indicating the light emission order “3” of the LED 3 and information indicating the light emission order “4” of the LED 4 in the direction directly opposite to the head direction of the person P. It passes to the setting part 15 as information to show.

  The setting unit 15 illustrated in FIG. 11 includes an orientation specifying unit 153 and an ID table 154. The ID table 154 holds an orientation code indicating the light emission direction of each of the LEDs 1 to 5 included in the light projecting unit 12 corresponding to the identification information given to each light projecting unit 12. The azimuth specifying unit 153 refers to the ID table 154 based on the identification information Cord0 obtained by the extraction unit 145 and the light emission order obtained by the determination unit 146, so that the light incident on the light receiving unit 13 can be obtained. An azimuth code indicating the direction of light emission from the light emitting LED is acquired.

  As described above, the light emitting direction of the light emitting LED that has entered the light receiving unit 13 indicates the head direction of the person P. Therefore, when the light emitting order indicating only one LED is specified by the determination unit 146, the direction code acquired by the direction specifying unit 153 referring to the ID table 154 indicates the head direction of the person. .

  On the other hand, when the direction specifying unit 153 receives information indicating the two light emission orders from the determination unit 146, the head of the person P is based on the two direction codes acquired from the ID table 154 corresponding to the light emission orders. An azimuth indicating a part direction may be calculated. Note that the method for calculating the azimuth indicating the head direction of the person P from the two azimuth codes is the same as the method described for the calculation unit 152 shown in FIG.

  According to the light projecting unit 12 illustrated in FIG. 10, it is possible to reduce the time for turning on the LEDs 1 to 5 as compared to the case where the LEDs 1 to 5 having directivity are blinked according to the corresponding direction codes. Thereby, while achieving power saving of each light projection part 12, consumption of each LED1-LED5 can be controlled. Further, the power consumption by the light projecting unit 12 may be further reduced by executing the transmission of the identification information by the LED 0 and the operation of sequentially causing the LEDs 1 to 5 to emit light at predetermined time intervals.

  Moreover, according to the light projection part 12 shown in FIG. 10, compared with the case where LED1-LED5 blinks according to the direction code corresponding to each, LED which has the directivity which has faced the light-receiving part 13 in a short time. Can be transmitted. Therefore, even when the rotation of the head of the person P is fast, the light receiving unit at the timing when the head direction of the person P and the light emission direction of any one of the LEDs 1 to 5 included in the light projecting unit 12 face each other. The LED that is directly facing 13 can be identified. Accordingly, the setting unit 15 shown in FIG. 11 can reset the tracking result obtained by the tracking unit 11 with high accuracy regardless of the movement speed of the person P. It can be kept high.

  By the way, when considering a system for providing information related to an object specified by a position on a horizontal plane as an application of the azimuth detecting device 10 of the present disclosure, the head of the person P corresponding to the left-right rotation of the head of the person P It is desirable to have high detection accuracy for the rotational component in the partial direction. On the other hand, in the above-described application, since the elevation angle component or depression angle component of the person P in the head direction does not contribute to the identification of the object, the azimuth detecting device 10 has a resolution for the elevation angle component or depression angle component of the person P in the head direction. You may identify without having.

  Next, a suitable light projecting unit 12 in the azimuth detecting device 10 applied to the above-described application will be described with reference to FIGS. 13 and 14.

  FIG. 13 shows another embodiment of the light projecting unit 12. Note that among the constituent elements shown in FIG. 13, those equivalent to the constituent elements shown in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 13A shows a horizontal plane of each of the LEDs 1 to LED 5 included in the light projecting unit 12 and the shielding plates S0, S1, S2, S3, S4, and S5 that limit the light emission direction of the LEDs 1 to LED5. The arrangement at is shown.

  FIG. 13B shows a front view of the light projecting unit 12 as seen from the light emitting direction Ze3 of the LED 3. In FIG. 13B, symbol α3 indicates a range in which the light emitted by the LED 3 shown in FIG.

  As can be seen from FIG. 13B, the light emitted by the LED 3 is limited to a narrow range in the horizontal direction by the shielding plates S2 and S3 disposed on both sides of the LED 3, but wide in the vertical direction. Spread to range. That is, by arranging the shielding plates S0 to S5 so as to separate the LEDs 1 to LED5 from each other, higher directivity than the vertical direction can be given to the LEDs 1 to LED5 in the horizontal direction.

  Therefore, according to the light projection part 12 shown in FIG. 13, the light by each LED1-LED5 can be inject | emitted in the range which is narrow in a horizontal direction and spreads in a vertical direction greatly. Thereby, it is possible to increase the possibility that the light from the light projecting unit 12 enters the light receiving unit 13 shown in FIG. Furthermore, if the light from the light projecting unit 12 shown in FIG. 13 is detected by using the light receiving unit 13 shown in FIGS. 6 and 7, the person P's head angle direction regardless of the elevation angle component of the person P. It is possible to detect the direct alignment of the light emission direction by either the rotation component in the head direction or the LED of the light projecting unit 12.

  Note that the light projecting unit 12 shown in FIG. 13 can be replaced with the light projecting unit 12 shown in FIG. Therefore, by controlling the blinking of each LED1 to LED5 included in the light projecting unit 12 shown in FIG. 13 by the control unit 121 shown in FIG. 8, the direction code corresponding to these LEDs 1 to LED5 is sent out. Also good.

  The direction codes corresponding to the respective LEDs 1 to 5 included in the light projecting unit 12 illustrated in FIG. 13 are caused to blink sequentially according to the respective direction codes in the same manner as the light projecting unit 12 illustrated in FIG. You may send it. Moreover, as shown in FIG. 14, you may perform control which blinks alternately according to an azimuth | direction code about adjacent LED.

  FIG. 14 is a diagram illustrating transmission / reception of a direction code. In FIG. 14, each of the codes Cord1, Cord2, Cord3, Cord4, and Cord5 indicates an orientation code corresponding to LED1, LED2, LED3, LED4, and LED5 shown in FIG.

  14 (A) to 14 (E) show that the LED 1 to LED 5 shown in FIG. 13 blinks in a time-sharing manner to transmit the corresponding direction codes Cord1, Cord2, Cord3, Cord4, Cord5. Is shown. The example of FIG. 14 shows a case where the control unit 121 shown in FIG. 8 controls the five LEDs 1 to 5 by dividing them into a group 1 including LED1, LED3 and LED5 and a group 2 including LED2 and LED4. ing.

  14F and 14G show examples of electrical signals obtained by the light receiving unit 13. FIG. In the example of FIG. 14F, when the light from the LEDs 2 belonging to the group 2 is incident on the light receiving unit 13 illustrated in FIG. 8, the light receiving unit 13 generates an electrical signal indicating the above-described direction code Cord2. It is shown that. In the example of FIG. 14G, the light from the LED 3 belonging to the group 1 and the light from the LED 4 belonging to the group 2 are incident on the light receiving unit 13. It is shown that an electrical signal indicating is generated.

  Further, based on the electrical signal obtained by the light receiving unit 13, the collating unit 143 of the detecting unit 14 illustrated in FIG. 8 performs a collation process with the orientation code held in the code table 144, thereby obtaining the light receiving unit 13. The LED corresponding to the light incident on and the emission direction thereof can be specified.

  According to the azimuth detecting device 10 including the light projecting unit 12 shown in FIG. 13, similarly to the azimuth detecting device 10 shown in FIG. The tracking result in the head direction of the person P can be reset using the absolute direction.

  As described above, according to the light projecting unit 12 shown in FIG. 13, the light from the light projecting unit 12 is emitted by emitting light from the LEDs 1 to 5 to a range narrow in the horizontal direction and wide in the vertical direction. However, it is possible to increase the possibility of entering the light receiving unit 13 shown in FIG. That is, regardless of whether the person P is looking upward or tingling, the head direction of the person P and the LEDs of the light projecting unit 12 are determined based on the rotation component in the horizontal direction of the person P's head direction. Either way, it is possible to detect the direct facing of the light emission direction.

  Therefore, according to the azimuth detecting device 10 including the light projecting unit 12 illustrated in FIG. 13, the rotation component in the head direction of the person P and the light emission direction by any one of the LEDs of the light projecting unit 12 face each other. The tracking result obtained by the inertial navigation technique can be reset using an absolute angle without missing. Thereby, since an absolute azimuth is frequently set in the tracking result obtained by the tracking unit 11 included in the azimuth detecting device 10, an error included in the detection result by the azimuth detecting device 10 can be more strongly suppressed. This is useful for improving the detection accuracy of the azimuth detecting device 10.

  By the way, the azimuth | direction detection apparatus 10 of this indication can also be utilized for specification of the absolute position of the person P who moves indoors. Next, as an application example of the azimuth detection device 10 disclosed herein, a method for specifying the position of the person P will be described with reference to FIGS. 15 and 16.

  FIG. 15 shows an application example of the direction detection device 10. Note that among the constituent elements shown in FIG. 15, the same constituent elements as those shown in FIG. 1 and FIG.

  In the room C shown in FIG. 15, two anchor units AU1 and AU2 are installed. The anchor unit AU1 includes three light projecting units 12-1, 12-2, and 12-3, while the anchor unit AU2 includes another three light projecting units 12-4, 12-5, and 12-. 6 is included. Each of the light projecting units 12-1 to 12-6 included in the anchor units AU1 and AU2 may have the same configuration as that shown in the light projecting unit 12 shown in FIG. You may have the structure similar to the light projection part 12 shown in FIG. Further, the distance between the installation positions of the two anchor units AU1 and AU2 shown in FIG.

  When the person P shown in FIG. 15 rotates the head, the direction of the head changes from the direction Q1 toward the installation location of the anchor unit AU1 to the direction Q2 toward the installation location of the anchor unit AU2. Think about the case.

  In this case, the azimuth detecting device 10 including the light receiving unit 13 attached to the head of the person P, as a detection result by the detecting unit 14, shows an azimuth code indicating the azimuth in the direction Q1 and an azimuth code indicating the azimuth in the direction Q2. And can get. In the example of FIG. 15, the absolute direction φ1 with reference to the direction of the wall W of the room C is obtained as the direction code indicating the direction of the direction Q1, and the wall code is also used as the direction code indicating the direction of the direction Q2. An absolute azimuth φ2 with respect to the azimuth of W is obtained.

  Based on the absolute orientations φ1 and φ2 obtained as described above and the distance D between the anchor units AU1 and AU2, the position of the person P can be obtained geometrically. That is, according to the azimuth detecting device 10 shown in FIG. 15, when the person P performs an operation of looking around, the absolute position of the person P can be specified.

  The installation locations of the anchor units AU1, AU2 are not limited to the corners of the room C shown in the example of FIG. For example, the anchor units AU1 and AU2 may be installed on two walls sandwiching one corner of the room C at positions separated from the above-mentioned corners by a predetermined distance D1 and D2, respectively.

  Further, instead of using the action of the person P looking around, the person P may be equipped with a plurality of light receiving units 13 to simultaneously detect light from the plurality of anchor units.

  FIG. 16 shows another application example of the direction detection device 10. Note that among the constituent elements shown in FIG. 16, the same constituent elements as those shown in FIGS. 1, 5, and 15 are denoted by the same reference numerals, and description thereof is omitted.

  Anchor units AU1 and AU2 are respectively installed on the walls W1 and W2 shown in FIG. The anchor units AU1 and AU2 each include six light projecting units corresponding to the light projecting unit 12 shown in FIG. In FIG. 16, the reference numerals indicating the light projecting units included in the anchor units AU1 and AU2 are not shown. Moreover, the code | symbol D1 shown in FIG. 16 has shown the distance from the location where wall W1, W2 crosses to the installation location of anchor unit AU1. Similarly, the symbol D2 shown in FIG. 16 indicates the distance from the location where the walls W1, W2 intersect to the location where the anchor unit AU2 is installed.

  The azimuth detecting device 10 shown in FIG. 16 includes two light receiving units 13-L and 13-R mounted on the left and right sides of the head of the person P. In the example of FIG. 16, the light receiving unit 13 -L is mounted by being inclined by an angle θL counterclockwise with respect to the head direction of the person P, and the light receiving unit 13 -R is mounted in the head direction of the person P. On the other hand, it is mounted inclined at an angle θR clockwise.

  When the person P shown in FIG. 16 points his head near the place where the walls W1 and W2 intersect, the light from the anchor unit AU1 and the light from the anchor unit AU2 are simultaneously received by the light receiving unit 13-R. And the light receiving unit 13-L.

  In this case, based on the electrical signal obtained by the light receiving unit 13-R, the detection unit 14 acquires an orientation code corresponding to the light incident on the light receiving unit 13-R. At the same time, the detection unit 14 acquires an orientation code corresponding to the light incident on the light receiving unit 13-L based on the electrical signal obtained by the light receiving unit 13-L. In the example of FIG. 16, the detection unit 14 acquires an absolute direction φ1 based on the direction of the wall W1 described above as the direction code corresponding to the light incident on the light receiving unit 13-R. Further, the detection unit 14 acquires an absolute direction φ2 based on the direction of the wall W2 orthogonal to the wall W1 as the direction code corresponding to the light incident on the light receiving unit 13-L.

  As described above, the distances D1 and D2 from the location where the walls W1 and W2 intersect to the location where the anchor units AU1 and AU2 are installed and the angles θR and θL shown in FIG. 16 are known. Therefore, the position of the person P can be obtained by a geometric method based on the directions φ1 and φ2 obtained by the detection unit 14. Further, as described with reference to FIG. 15, when the person P looks around, the person P is based on the direction code corresponding to the light incident on at least one of the light receiving units 13 -R and 13 -L. It is also possible to perform a process of specifying the position of.

  In addition, if the direction detection device 10 disclosed herein is used, for example, a service that provides information about an exhibition booth that exists in the head direction of a person among a plurality of exhibition booths that are exhibited at an exhibition hall or the like. Can be realized. Hereinafter, an information providing system including the azimuth detecting device 10 disclosed herein will be described.

  FIG. 17 shows an embodiment of the information providing system. Note that, among the components shown in FIG. 17, the same components as those shown in FIG. 15 are denoted by the same reference numerals, and description thereof is omitted.

  Reference numerals B1, B2, B3, and B4 shown in FIG. 17 indicate exhibition booths installed in the exhibition hall H, respectively. Further, the symbol UE indicates a mobile terminal device possessed by the person P. The mobile terminal device UE is connected to the computer device 20 via a network NW such as a wireless LAN (Local Area Network).

  17 includes, for example, a headset 30 attached to the head of a person P, the above-described mobile terminal device UE, and at least one anchor unit AU previously installed in the exhibition hall H. Including. In the example of FIG. 17, a case where two anchor units AU1 and AU2 are installed in the exhibition hall H is shown.

  The computer device 20 shown in FIG. 17 stores therein information related to the above-described exhibition booths B1 to B4, and relates to the exhibition booths B1 to B4 to the portable terminal device UE of the person P via the network NW described above. Has a function to provide information.

  FIG. 18 illustrates a hardware configuration example of an information providing system including the direction detection device 10. Note that, among the components shown in FIG. 18, components equivalent to those shown in FIG. 17 are denoted by the same reference numerals, and description thereof is omitted.

  In the example of FIG. 18, the headset 30 included in the azimuth detection device 10 is attached to the vine portion of the person's P glasses, so that the optical axis direction of the light receiving unit 13 included in the headset 30 is Adjustment to match the direction of the part is made easy. As described above, the light receiving unit 13 shown in FIGS. 6 and 7 can be downsized to such an extent that it can be attached to the vine portion of the glasses. The headset 30 and the mobile terminal device UE will be described with reference to FIG.

  The computer device 20 shown in FIG. 18 includes a processor 21, a memory 22, a hard disk device 23, a network interface 24, and an optical drive 25. The processor 21, the memory 22, the hard disk device 23, the network interface 24, and the optical drive device 25 illustrated in FIG. 18 are connected to one another via a bus.

  The optical drive device 25 described above can be loaded with a removable disk 26 such as an optical disk, and reads and records information recorded on the mounted removable disk 26.

  Further, the computer device 20 has a function of exchanging information with the portable terminal device UE of the person P through the network interface 24 and the network NW. Similarly, the computer device 20 may be connected to the anchor units AU1 and AU2 included in the azimuth detecting device 10 via the network interface 24 and the network NW.

  In addition to the operating system of the computer device 20, the memory 22 stores an application program for the processor 21 to execute processing for providing information to the person P regarding the exhibition booths B1 to B4 shown in FIG. The application program for executing the information providing process can be recorded and distributed on a removable disk 26 such as an optical disk, for example. Then, an application program for executing the information providing process may be stored in the memory 22 and the hard disk device 23 by mounting the removable disk 27 in the optical drive device 25 and performing a reading process. In addition, an application program for executing information providing processing can be read into the memory 22 and the hard disk device 23 via the network interface 24.

  Further, the memory 22 or the hard disk device 23 of the computer device 20 holds information indicating the arrangement of the exhibition booths B1 to B4 in the exhibition hall H and information related to the exhibition contents of the individual exhibition booths B1 to B4. desirable.

  FIG. 19 illustrates a hardware configuration example of the mobile terminal device UE and the headset 30. Note that, among the components shown in FIG. 19, the same components as those shown in FIGS. 1 and 17 are denoted by the same reference numerals, and the description thereof is omitted.

  The headset 30 shown in FIG. 19 includes a processor 31, a memory 32, a sensor interface 33, and a wireless communication interface 34. The processor 31, the memory 32, the sensor interface 33, and the wireless communication interface 34 are connected to each other via a bus. Further, the processor 31 can receive information indicating a measurement result by the light receiving unit 13 and the angular velocity sensor Sa via the sensor interface 33.

  For example, the angular velocity sensor Sa shown in FIG. 19 detects the angular velocity with respect to the rotational motion about the vertical axis of the head of the person P, and sends the angular velocity data indicating the detected angular velocity to the processor 31 via the sensor interface 33. hand over. The sensor interface 33 has a function of generating digital data from the electrical signal obtained by the light receiving unit 13 and passing the generated digital data to the processor 31.

  The memory 32 included in the headset 30 stores a program for processing to collect information obtained by the angular velocity sensor Sa and the light receiving unit 13 via the sensor interface 33. A program for processing for collecting measurement results is, for example, a program for processing for detecting the above-mentioned direction code from digital data generated by the sensor interface unit 33 in accordance with an electrical signal obtained by the light receiving unit 13. May be included. Further, information corresponding to the code table 144 shown in FIG. 8 may be stored in the memory 32 together with a program for processing for detecting the direction code. In this case, the function of the specifying unit 142 shown in FIG. 8 can be realized by the processor 31 performing processing for detecting the direction code in accordance with the program stored in the memory 32. Further, the memory 32 further stores a program for processing to transmit the collected information to the mobile terminal device UE through the wireless communication interface 34.

  The mobile terminal device UE illustrated in FIG. 19 includes a processor 41, a memory 42, a wireless communication interface 43, a network interface 44, a display control unit 45, and a liquid crystal display unit 46. The mobile terminal device UE further includes an audio processing unit 47 and a speaker SP, an acceleration sensor 48, and a sensor interface 49.

  The processor 41, the memory 42, the wireless communication interface 43, the network interface 44, the display control unit 45, the sound processing unit 47, and the sensor interface 49 are connected to each other via a bus. The processor 41 is connected to the above-described network NW via the network interface 44, and can exchange information with, for example, the computer apparatus 20 illustrated in FIG. 18 via the network NW. Further, the processor 41 is connected to the headset 30 described above via the wireless communication interface 43 and can receive information from the headset 30.

  The memory 42 included in the mobile terminal device UE stores, in addition to the operating system of the mobile terminal device UE, a first application program for operating the mobile terminal device UE as a part of the azimuth detection device 10 disclosed herein. doing. The first application program can also be stored in the memory 42 of the mobile terminal device UE via the network interface 24 and the network NW, for example, by the computer device 20 described above.

  The first application program described above includes a program for processing for tracking the head direction of the person P based on the angular velocity data included in the information passed from the headset 30. Therefore, when the processor 41 executes a program for processing to track the head direction of the person P, the function of the tracking unit 11 shown in FIG. 8 can be realized. Further, the first application program described above is used for the process of resetting the tracking result of the head direction of the person P using the direction code when the direction code is included in the information passed from the headset 30. Contains the program. The processor 41 executes the program for the process of resetting the tracking result of the person P in the head direction, so that the function of the setting unit 15 illustrated in FIG. 8 can be realized. In the following description, the head direction tracking process using inertial navigation technology and the process of resetting the tracking result obtained by the tracking process based on the direction code included in the information from the headset 30 are performed. The combined process of the first application program is referred to as a direction detection process.

  Further, the memory 42 is a second application program for processing for providing the information received from the computer device 20 shown in FIG. 18 via the network NW to the person P via the voice processing unit 47 and the display control unit 45. Is stored.

  Hereinafter, a method for providing information related to the exhibition booths B1 to B4 based on the head direction of the person P obtained by the azimuth detecting device 10 of the present disclosure by the information providing system illustrated in FIGS. 17 and 18 will be described. To do.

  FIG. 20 shows an example of a flowchart of the information providing process. Each process of step 301 to step 307 illustrated in FIG. 20 is an example of a process included in the application program for the information providing process. Each process of step 301 to step 307 illustrated in FIG. 20 is executed by the processor 21 of the computer apparatus 20.

  For example, the processor 21 provides information when it detects that the person P has entered the exhibition hall H shown in FIG. 17 based on a radio signal from the mobile terminal device UE possessed by the person P. Processing may be started.

  First, the processor 21 causes the mobile terminal device UE to start tracking processing of the position and head direction of the person P via the network interface 24 illustrated in FIG. 18 (step 301). For example, the processor 21 may instruct the mobile terminal device UE to execute the first application program described above. Further, in the process of step 301, the processor 21 transmits an initial value of the position of the person P and an initial value of the head direction to the mobile terminal device UE, and sets initial values for the tracking processing of the position and head direction. Also good. For example, the processor 21 may pass position information indicating the entrance of the exhibition hall H to the mobile terminal device UE as an initial value of position tracking processing by the second application program. Further, for example, the processor 21 may pass, as an initial value in the head direction of the person P, information indicating the direction of entering the inside of the exhibition hall H from the entrance described above to the mobile terminal device UE.

  Based on the initial value received from the processor 21 in the process of step 301, the mobile terminal device UE starts a tracking process for the position of the person P and a process for detecting an orientation indicating the head direction of the person P.

  The processor 21 acquires information indicating the current position of the person P as the execution result of the tracking process for the position of the person P from the mobile terminal device UE (step 302). Further, the processor 21 acquires information indicating the current head direction of the person P as an execution result of the process of detecting the orientation indicating the head direction of the person P from the mobile terminal UE (step 303). Note that the processor 21 may execute the process of step 302 and the process of step 303 in the reverse order.

  Here, the process for detecting the orientation indicating the head direction of the person P will be described with reference to FIGS. 21 and 22.

  FIG. 21 shows an example of a flowchart of processing for detecting an orientation indicating the head direction. Each process of step 311 to step 317 illustrated in FIG. 21 is an example of a process included in an application program for a process of detecting an orientation indicating the head direction. The process of step 311 shown in FIG. 21 is executed by the processor 31 of the headset 30 shown in FIG. In addition, each process of step 312 to step 317 is executed by the processor 41 of the mobile terminal device UE.

  21 is an example of processing for tracking the head direction of the person P using the same inertial navigation technique as that of the prior art. The flowchart illustrated in FIG. 21 illustrates an example in which a reference for tracking processing is set by the azimuth detection device 10 of the present disclosure prior to tracking processing in the head direction by the inertial navigation technique.

  First, in step 311, the processor 31 of the headset 30 moves from the light projecting unit 12 included in the anchor units AU1 and AU2 shown in FIG. The light projecting unit 12 that directly faces is detected.

  FIG. 22 shows an example of a flowchart of processing for detecting a light projecting unit that faces the camera. Each process of step 321 to step 328 illustrated in FIG. 22 is an example of a process included in a program stored in the memory 32. Each process of step 321 to step 328 shown in FIG. 22 is executed by the processor 31 of the headset 30.

  First, the processor 31 acquires an output signal obtained by digitizing an electrical signal output by the light receiving unit 13 via the sensor interface 33 shown in FIG. 19 (step 321).

  Next, the processor 31 collates the output signal acquired in step 321 with each bit pattern included in the code table 144 provided in the memory 32 to thereby indicate the direction code indicating the light projecting unit 12 facing the head direction. Is detected (step 322). As described above, the function of the specifying unit 142 illustrated in FIG. 8 may be realized by the processor 31 executing the process of step 322.

  When the direction code matching the output signal is found in the process of step 322, the processor 31 determines that the direction code has been detected, and proceeds to the affirmative determination route of step 323.

  In the affirmative determination route of step 323, the processor 31 first determines whether there is one detected direction code (step 324).

  When there is one azimuth code detected in step 322, the processor 31 proceeds to step 325 according to the affirmative determination route of step 324. In step 325, the processor 31 specifies the first orientation indicating the orientation of the light projecting unit 12 facing the head direction of the person P based on the orientation code detected in the processing of step 322.

  On the other hand, when there are two azimuth codes detected in the process of step 322, the processor 31 proceeds to step 326 according to the negative determination route of step 324. In step 326, the processor 31 calculates the first direction based on the two direction codes detected in the process of step 322. For example, the processor 31 may obtain an average value of angles indicating the azimuths indicated by the two azimuth codes, and may use the obtained average value as the first azimuth. Thus, the processor 31 may implement the functions of the determination unit 151 and the calculation unit 152 illustrated in FIG. 8 by executing the processing of step 326 in the negative determination route of step 324.

  The affirmative determination route and the negative determination route in step 324 merge in step 327. The processor 31 transmits information indicating the first orientation obtained in the above-described step 325 or step 326 to the mobile terminal device UE via the wireless communication interface 34 (step 327).

  On the other hand, when the direction code matching the output signal is not found in the process of step 322, the processor 31 proceeds to the process of step 328 according to the negative determination route of step 323. In step 328, the processor 31 transmits to the mobile terminal device UE via the wireless communication interface 34 that the process of detecting the facing light projecting unit has failed.

  When the processor 31 executes the above-described processing, information for identifying the direction code indicating the light projecting unit 12 facing the head direction of the person P wearing the headset 30 is obtained as the processing result of step 311 in FIG. It can be passed to the mobile terminal device UE.

  Based on the information received from the headset 30, the processor 41 of the mobile terminal device UE first determines whether or not the detection of the light projecting unit 12 facing the person P in the head direction has succeeded (step 312). .

  When the first orientation is obtained as the processing result of step 311, the processor 41 executes the processing of step 313 according to the affirmative determination route of step 312. In step 313, the processor 41 sets the first azimuth as the azimuth indicating the head direction of the person P regardless of the tracking result of the head direction obtained so far by the inertial navigation technique. That is, the processor 41 resets the tracking result in the head direction obtained by inertial navigation based on the angular velocity data with the first orientation, and uses the first orientation as a reference for the subsequent tracking processing. As described above, the function of the setting unit 15 illustrated in FIG. 1 may be realized by the processor 41 performing the process of step 313 in response to the positive determination of step 312.

  On the other hand, when the first orientation is not included in the information obtained as the processing result of step 311, the processor 41 skips step 313 described above according to the negative determination route of step 312.

  The affirmative determination route and the negative determination route in step 312 are merged in step 314, and the processor 41 performs head direction tracking processing by inertial navigation in step 314 and step 315. First, the processor 41 acquires angular velocity data obtained by the angular velocity sensor Sa included in the headset 30 via the wireless communication interface 44 (step 314). Next, the processor 41 calculates a change from the tracking result obtained immediately before based on the angular velocity data acquired in step 314, and adds the calculated change to the previous tracking result to thereby obtain the current person. A new tracking result indicating the head direction of P is obtained (step 315).

  In the process of step 315, the processor 41 transmits information indicating the head direction of the person P obtained as a new tracking result to the computer apparatus 20 via the network interface 44 (step 316). When the processor 41 is requested to transmit information indicating the head direction of the person P from the computer device 20, the processor 41 transmits information indicating the latest tracking processing result obtained through the previous tracking processing via the network interface 44. May be transmitted to the computer device 20.

  In this way, the processor 41 executes the process of step 315, so that information indicating the head direction of the person P can be passed to the computer apparatus 20 as the process result of step 303 shown in FIG.

  Note that the processor 41 of the mobile terminal device UE may repeatedly execute the above-described processing of step 311 to step 316 until it is determined in step 317 that tracking is to be ended. Note that the processor 41 detects the head direction of the person P when, for example, the power of the mobile terminal device UE is turned off or the connection with the computer device 20 is released by an operation by the person P. The process of tracking the process may be terminated.

  Here, in step 316 described above, the orientation indicating the head direction of the person P passed from the mobile terminal device UE to the computer device 20 has higher accuracy than the tracking result obtained by the conventional inertial navigation technique. Yes. Because the head direction of the person P directly faces the light projecting unit 12 included in one of the anchor units AU1 and AU2 shown in FIG. This is because the error accumulated in the tracking result is cleared.

  Therefore, in the information providing system including the azimuth detection device 10 of the present disclosure, the computer device 20 can acquire highly reliable information as the azimuth indicating the head direction of the person P.

  The processor 21 of the computer device 20 identifies an exhibition booth that exists in the head direction of the person P based on the current position of the person P and the heading indicating the head direction of the person P (step 304). The processor 21 acquires information indicating the arrangement of the exhibition booths B1 to B4 shown in FIG. 17 from the memory 22 or the hard disk device 23, and based on the acquired information and the position and head direction of the person P, the person P You may specify the exhibition booth which exists in the head direction.

  Next, the processor 21 creates guide information corresponding to the specified exhibition booth (step 305). For example, the processor 21 acquires information about the specified exhibition booth from the memory 22 or the hard disk device 23, and creates guidance information for introducing the exhibition booth to the person P based on the acquired information. May be.

  Next, the processor 21 transmits the guidance information created in the process of step 305 to the portable terminal device UE of the person P via the network interface 24 and instructs the provision of the guidance information (step 306). For example, the processor 21 may instruct the mobile terminal device UE to execute the above-described second application program in the process of step 306. In response to this instruction, the processor 41 of the mobile terminal device UE executes the second application program, so that the received guidance information can be provided to the person P via the voice processing unit 47 and the display control unit 45.

  Thereafter, in step 307, the processor 21 determines whether or not to continue the information providing process. For example, when it is detected that the person P has gone outside the exhibition hall H, or when the mobile terminal device UE is requested to stop providing information, the processor 21 determines that it is not necessary to continue the information providing process. To do. When determining that the continuation of the information providing process is unnecessary, the processor 21 ends the information providing process according to the affirmative determination route of step 307. In other cases, the processor 21 returns to the process of step 302 according to the affirmative determination route of step 307 and continues the information providing process.

  As described above, according to the information providing system using the azimuth detecting device 10 disclosed in the present disclosure, the exhibition booth that exists in the head direction of the person P based on the position and the head direction of the person P in the exhibition hall H. It is possible to realize a service that provides information related to timely. The information providing system described above can be applied not only to providing guidance information at an exhibition hall, but also to providing guidance information in an amusement facility or public institution facility.

Regarding the above description, the following items are further disclosed.
(Supplementary Note 1) A tracking unit that is mounted on a person's head and tracks an azimuth indicating the head direction of the person based on an angular velocity obtained by an angular velocity sensor that observes the rotational motion of the head;
A light projecting unit installed indoors for emitting light having directivity in a predetermined direction;
A light receiving unit mounted on the head of the person, having directivity with respect to incident light from the head direction of the person, and converting the incident light into an electrical signal;
Based on an electrical signal obtained by the light receiving unit, a detection unit that detects a direct pairing between the head direction of the person and the emission direction in which light is emitted by the light projecting unit;
When a direct alignment between the light emitting direction by the light projecting unit and the head direction of the person is detected, the first direction corresponding to the light emitting direction by the light projecting unit is tracked by the tracking unit. An azimuth detecting apparatus comprising: a setting unit configured to set the azimuth indicating the current head direction of the obtained person.
(Supplementary note 2) In the bearing detection device according to supplementary note 1,
The light projecting unit is
A plurality of first light emitting elements that respectively emit light in different predetermined directions;
A controller that causes each of the plurality of first light emitting elements to blink in a different pattern,
The detector is
A specifying unit that specifies a first light emitting element that exists in a direction directly opposite to the head direction of the person from among the plurality of first light emitting elements based on a temporal change in an electrical signal obtained by the light receiving unit. Have
The setting unit sets an azimuth indicating a current head direction of the person with the light emission direction of the first light emitting element specified by the specifying unit as the first azimuth. Detection device.
(Supplementary Note 3) In the bearing detection device according to Supplementary Note 2,
The light projecting unit is
In addition to the plurality of first light emitting elements, a second light emitting element that emits light in a range including the light emission direction of each of the plurality of first light emitting elements is provided,
The controller is
Alternately executing a control of blinking the second light emitting element in a pattern indicating identification information of the light projecting unit and a control of sequentially emitting each of the plurality of first light emitting elements,
The specific part is:
An extraction unit for extracting identification information of the light projecting unit from a temporal change of an electrical signal obtained by the light receiving unit in response to blinking of light by the second light emitting element;
Based on the elapsed time from the completion of extraction of the identification information by the extraction unit to the change of the electrical signal due to light emission of any of the plurality of first light emitting elements, in a direction facing the head direction of the person An orientation detection apparatus comprising: a discrimination unit that discriminates an existing first light emitting element.
(Supplementary note 4) In the bearing detection device according to supplementary note 3,
The azimuth detecting device according to claim 1, wherein the control unit controls each of the plurality of first light emitting elements to emit light at a timing different from the predetermined time by a time equal to or shorter than the predetermined time.
(Supplementary Note 5) In the bearing detection device according to Supplementary Note 2,
The light projecting unit further includes a light shielding plate provided between the first light emitting elements adjacent in the horizontal direction,
The control unit performs control to alternately emit light every other first light emitting element,
The light receiving unit is
A photoelectric conversion element that generates an electrical signal reflecting the intensity change of incident light;
A mask having an opening which is disposed on the light incident side of the photoelectric conversion element photoelectric conversion element and has a small width in the horizontal direction compared to the length in the vertical direction;
A light beam having an optical axis perpendicular to the light receiving surface of the photoelectric conversion element and incident at an angle within a predetermined range centering on the optical axis is imaged on the opening of the mask and exceeds the predetermined range An azimuth detecting device comprising: an imaging optical system that forms an image of a light beam incident at an angle outside the opening of the mask.
(Supplementary note 6) In the bearing detection device according to supplementary note 5,
The imaging optical system includes a lens having a refractive power in a horizontal direction.
(Supplementary Note 7) In the bearing detection device according to Supplementary Note 2,
When the two first light-emitting elements are specified by the specifying unit, the setting unit has an orientation indicating an intermediate direction of the light emission direction of each of the two first light-emitting elements as the head of the person. An azimuth detection device comprising: a calculation unit configured to calculate the first azimuth facing the direction.

DESCRIPTION OF SYMBOLS 10 ... Direction detection apparatus; 11 ... Tracking part; 12 ... Light projection part; 13 ... Light receiving part; 14 ... Detection part; 15 ... Setting part; 121 ... Control part; 133 ... Linear Fresnel lens; 134 ... Slit plate; 141 ... Signal processing unit; 142 ... Identification unit; 143 ... Verification unit; 144 ... Code table; 145 ... Extraction unit; ... Calculation unit; 153 ... Direction specifying unit; 154 ... ID (IDentifier) table; 20 ... Computer device; 21, 31, 41 ... Processor; 22,32,42 ... Memory; 23 ... Hard disk device; 24,44 ... Network interface 25 ... optical drive; 26 ... removable disk; 33, 49 ... sensor interface; 34, 43 ... wireless communication interface; 45 ... Display control unit; 46 ... Liquid crystal display unit; 47 ... Audio processing unit; 48 ... Acceleration sensor; S0, S1, S2, S3, S4, S5 ... Shield plate; Sa ... Angular velocity sensor; SP ... Speaker; Anchor unit

Claims (4)

A tracking unit that is attached to the head of a person and tracks an azimuth indicating the head direction of the person based on an angular velocity obtained by an angular velocity sensor that observes the rotational motion of the head;
A light projecting unit installed indoors for emitting light having directivity in a predetermined direction;
A light receiving unit mounted on the head of the person, having directivity with respect to incident light from the head direction of the person, and converting the incident light into an electrical signal;
Based on an electrical signal obtained by the light receiving unit, a detection unit that detects a direct pairing between the head direction of the person and the emission direction in which light is emitted by the light projecting unit;
When a direct alignment between the light emitting direction by the light projecting unit and the head direction of the person is detected, the first direction corresponding to the light emitting direction by the light projecting unit is tracked by the tracking unit. A setting unit that sets the orientation indicating the current head direction of the obtained person ,
The light projecting unit is
A plurality of first light emitting elements that respectively emit light in different predetermined directions;
A controller that causes each of the plurality of first light emitting elements to blink in a different pattern,
The detector is
A specifying unit that specifies a first light emitting element that exists in a direction directly opposite to the head direction of the person from among the plurality of first light emitting elements based on a temporal change in an electrical signal obtained by the light receiving unit. Have
The setting unit sets an azimuth indicating the current head direction of the person with the light emitting direction of the first light emitting element specified by the specifying unit as the first azimuth.
An azimuth detecting device characterized by that. In the azimuth detecting device according to claim 1 ,
The light projecting unit is
Apart from the plurality of first light-emitting element, a second light emitting element that emits light in the range including the emission direction of light by each of the plurality of first light emitting element,
The controller is
Alternately executing a control of blinking the second light emitting element in a pattern indicating identification information of the light projecting unit and a control of sequentially emitting each of the plurality of first light emitting elements,
The specific part is:
An extraction unit for extracting identification information of the light projecting unit from a temporal change of an electrical signal obtained by the light receiving unit in response to blinking of the second light emitting element;
Based on the elapsed time from the completion of extraction of the identification information by the extraction unit to the change of the electrical signal due to light emission of any of the plurality of first light emitting elements, in a direction facing the head direction of the person An orientation detection apparatus comprising: a discrimination unit that discriminates an existing first light emitting element. In the azimuth detecting device according to claim 1 ,
The light projecting unit further includes a light shielding plate provided between each of the two first light emitting elements adjacent in the horizontal direction,
The control unit performs control to alternately emit light every other first light emitting element,
The light receiving unit is
A photoelectric conversion element that generates an electrical signal reflecting the intensity change of incident light;
A mask disposed on the light incident side of the photoelectric conversion element and having an opening having a small width in the horizontal direction compared to the length in the vertical direction;
A light beam having an optical axis perpendicular to the light receiving surface of the photoelectric conversion element and incident at an angle within a predetermined range centering on the optical axis is imaged on the opening of the mask and exceeds the predetermined range An azimuth detecting device comprising: an imaging optical system that forms an image of a light beam incident at an angle outside the opening of the mask. In the azimuth detecting device according to claim 1 ,
When the two first light emitting elements are specified by the specifying unit, the setting unit displays an orientation indicating an intermediate direction of the light emission direction of each of the two first light emitting elements. An azimuth detection device comprising: a calculation unit configured to calculate the first azimuth facing the direction.

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