JP4877138B2 - Head motion tracker device - Google Patents

Description

The present invention relates to a head motion tracker (HMT) device having a function of detecting the position of an optical marker that emits a light beam. The present invention is used in, for example, an HMT device that detects the position and angle of a helmet with a head-mounted display device used in game machines, vehicles, and the like.

A technique for accurately measuring the position and angle of an object that changes from moment to moment is used in various fields. For example, in a game machine, an image is displayed by using a helmet with a head-mounted display device in order to realize virtual reality (VR). At this time, it is necessary to change the image in accordance with the position and angle of the helmet with a head-mounted display device. Therefore, in order to measure the position and angle of the helmet with a head-mounted display device, an HMT device is used.

Also, in order to avoid losing sight of the found rescue target in rescue operations by rescue flying boats, by locking when the aiming image displayed by the helmet with head mounted display device corresponds to the rescue target, Calculating the position of the locked rescue target has been done. At this time, in order to calculate the position of the rescue target, in addition to the latitude, longitude, altitude, and attitude of the flying object, the head angle and head position of the pilot with respect to the relative coordinate system set for the flying object are measured. ing. At this time, the HMT device is used.

As an HMT device used for a helmet with a head-mounted display device, an apparatus that optically measures the position and angle of the helmet with a head-mounted display device is disclosed (for example, see Patent Document 1). Specifically, as an optical marker, a plurality of reflectors are mounted on the outer periphery of the helmet with a head-mounted display device, and the light source and the two camera devices are fixed at the installation location, so that the light from the light source is emitted. The reflected light from the reflecting plate when irradiated is monitored by two camera devices. There is also an optical HMT device in which light emitters are attached to a plurality of locations so as to be separated from each other (see, for example, Patent Document 2). Specifically, on the outer peripheral surface of the helmet with a head-mounted display device, LEDs (light emitting diodes), which are light emitters, are attached at three locations as optical markers so as to be spaced apart from each other. The relationship is stored in advance in the HMT device. Then, these three LEDs are photographed at the same time by two camera devices that can be viewed stereoscopically and have a fixed installation location, thereby measuring the current positional relationship of the three LEDs based on the so-called triangulation principle. is doing. Thereby, the position and angle of the helmet with a head-mounted display device with respect to the two camera devices are specified.
JP-T 9-506194 Japanese Patent Application No. 2005-106458

However, since the optical HMT device as described above detects the light beam in a state where the three LEDs are always lit, there is no problem when detecting the light beam in a place where there is no disturbance light such as sunlight. However, when detecting light in a place where ambient light is present, the position of the three LEDs must be accurately measured because the ambient light is misrecognized as an LED or the amount of light from the LED decreases. There was something that could not be done.
Therefore, the present applicant causes the three LEDs to be turned on and off repeatedly, thereby turning on the light-on data detected when the three LEDs are turned on and the light-off data detected when the three LEDs are turned off. By applying the difference, an application has been filed for an HMT device that can generate difference data of light rays that will be emitted from only three LEDs. As a result, since the disturbance light is removed from the difference data, the positions of the three LEDs can be accurately measured without erroneously recognizing the disturbance light as an LED.

However, when an optical HMT device capable of generating difference data is used in a moving body such as an aircraft (for example, a rescue flight boat) or a ship or a vehicle, the movement of the moving body changes its posture. As a result, the position of disturbance light (especially sunlight) with respect to the two camera devices attached to the moving body sometimes fluctuated. For this reason, disturbance light cannot be completely removed in the difference data obtained by subtracting the light-on data detected when the three LEDs are turned on and the light-off data detected when the three LEDs are turned off. As a result, the position of the three LEDs may not be able to be measured due to erroneous recognition of disturbance light that could not be removed as an LED.
In view of this, the present invention moves the optical marker by accurately measuring the position of the optical marker without being affected by the disturbance light even when the position of the disturbance light is changed with respect to the optical detection means attached to the moving body. It is an object of the present invention to provide a head motion tracker device that can accurately calculate the position and angle of a passenger's head relative to the body.

The HMT device of the present invention made to solve the above problems is mounted on a head of a passenger, is attached to an optical marker that emits a light beam, and a moving body on which the passenger rides, and the optical Stereoscopic optical detection means for detecting light from the marker, and relative head for calculating relative head information including the head position and head angle of the occupant relative to the moving body based on the detected light A head motion tracker device comprising an information calculation unit, an optical marker driving unit that causes the optical marker to repeatedly turn on and off, and an angular velocity and / or acceleration that is attached to the moving body and acts on the moving body And the amount of movement angle of the moving body with respect to disturbance light based on the angular velocity and / or acceleration detected from the moving body sensor. Absolute mobile information calculation unit for calculating a non-absolute mobile body information, based on the absolute mobile body information, by calculating the movement position of light by the disturbance light to said optical detecting means, when the lighting of the optical markers thereby creating a compensation lighting data obtained by correcting the position of the light beam due to disturbance light from the lighting data of the detected light, and correcting the position of the light beam due to disturbance light from the off data of the detected light upon extinction of the optical markers complement positive off data to create a, by using the correction lighting data and correction off data, the a difference generating unit for generating differential data of light rays from only the optical markers, wherein the relative head information calculation unit The relative head information is calculated based on the difference data.

Here, the “moving body sensor” refers to a sensor that has three axes defined in the moving body sensor itself and can detect an angular velocity and acceleration in three axes directions based on these three axes. Examples include a gyro sensor and an acceleration sensor.
Examples of “disturbance light” include sunlight and reflected light of sunlight.
According to the HMT apparatus of the present invention, first, a light beam is detected when the optical marker is extinguished by an optical detection means capable of stereoscopic viewing and fixed to a moving body. At this time, since the optical marker is turned off, the current positional relationship between the moving body and the disturbance light is calculated by determining that the detected light beam is due to the disturbance light.
Thereafter, the absolute moving body information calculation unit calculates absolute moving body information including the moving angle amount of the moving body with respect to the disturbance light based on the angular velocity and / or acceleration detected by the moving body sensor. Thereby, the moving position amount of the light beam by the disturbance light detected by the optical detection means fixed to the moving body is calculated.
On the other hand, the optical marker driving unit alternately turns on and off the optical marker, thereby alternately switching on the light-on data detected when the optical marker is on and the light-off data detected when the optical marker is off. Get in order. At this time, the light-on data and the light-off data also include a light beam due to disturbance light or the like, and the position of the light beam due to disturbance light or the like is changed by moving the moving body so that its posture changes.
Therefore, the difference generation unit uses the moving position amount of the light beam due to the disturbance light detected by the optical detection means, and corrects the lighting of the light beam by correcting the position of the disturbance light from the lighting data of the light beam detected when the optical marker is turned on. In addition to creating data, corrected light extinction data of light is created by correcting the position of disturbance light from the light extinction data detected when the optical marker is extinguished. Thereby, the difference data of the light beam which will be emitted only from the optical marker is generated by subtracting the corrected lighting data and the extinction data or by subtracting the lighting data and the correction extinction data.
Finally, the relative head information calculation unit measures the position of the optical marker based on the difference data generated by the difference generation unit, thereby including the relative position including the passenger's head position and head angle relative to the moving body. Head information is calculated.

As described above, according to the HMT apparatus of the present invention, even if the position of the disturbance light varies with respect to the optical detection means attached to the moving body, the disturbance data is corrected from the difference data by correcting the position of the disturbance light. Since the light is completely removed, the position of the optical marker can be accurately measured without erroneously recognizing the disturbance light as the optical marker.

(Means and effects for solving other problems)
In the above invention, the optical marker may be three or more LEDs, and the optical detection means may be two or more camera devices.
In the above invention, the disturbance light may be sunlight.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and it goes without saying that various aspects are included without departing from the spirit of the present invention.

FIG. 1 is a diagram showing a schematic configuration of an HMT device according to an embodiment of the present invention, and FIG. 2 is a plan view of the helmet with a head-mounted display device shown in FIG. The HMT device 1 of the present embodiment has relative head information including a head position (Xh, Yh, Zh) and a head angle (Θh, Φh, Ψh) of a pilot (passenger) 3 with respect to a flying body (moving body). Is calculated. That is, with respect to the relative coordinate system (XYZ coordinate system) set for the flying object, the helmet coordinate system (X′Y′Z ′ coordinate system) set for the helmet 10 with a head-mounted display device worn by the pilot 3. Calculate position and angle. The relative coordinate system (XYZ coordinate system) is set with reference to a camera device (optical detection means) 2 described later, and is stored in the relative coordinate storage unit 43 of the memory 41, while the helmet coordinate system ( X′Y′Z ′ coordinate system) is set with reference to an LED group 7 described later, and is stored in the lighting data storage unit 44 of the memory 41.

The HMT device 1 includes a helmet 10 with a head mounted display device attached to the head of a pilot 3, a camera device 2 attached to the ceiling of the vehicle 30, and a three-axis gyro sensor attached to the vehicle 30. (Moving body sensor) 4 and a control unit 20 constituted by a computer.
The mounted body 30 is a cockpit of a flying body on which the pilot 3 is boarded, and includes a seat 30a on which the pilot 3 is seated. Then, sunlight (disturbance light) may enter the vehicle 30 on which the pilot 3 is boarded. In addition, this embodiment removes the influence of this sunlight (disturbance light).
The helmet 10 with a head-mounted display device includes a display (not shown), a combiner 8 that guides the eyes of the pilot 3 by reflecting image display light emitted from the display, and an LED group (optical marker). 7). In addition, the pilot 3 wearing the helmet 10 with a head-mounted display device can visually recognize the display image by the display and the front actual thing of the combiner 8.

As shown in FIG. 2, the LED group 7 is a head-mounted type in which three (or three or more) LEDs 7a, 7b, 7c emitting infrared light having different wavelengths are separated from each other. It is attached on the outer periphery of the helmet 10 with a display device.
Here, the helmet coordinate system (X′Y′Z ′ coordinate system) can arbitrarily determine the origin and the direction of each coordinate axis. In this embodiment, as shown in FIG. 2, the origin is the position of the LED 7a. As will be described later, the forward direction is defined as the X ′ axis direction, the forward direction is defined as the Y ′ axis direction, and the X ′ axis direction and the Y ′ axis direction are defined as the Z ′ axis direction. The lighting data storage unit 44 is set. In addition, the positional relationship (initial data) of the three LEDs 7 a, 7 b, 7 c on the helmet coordinate system (X′Y′Z ′ coordinate system) is also stored in the lighting data storage unit 44. Thereby, the position of the three LEDs 7a, 7b, and 7c at the present time is calculated by a triangulation method, which will be described later, and the initial position is referred to, so that the current position and the current angle of the head mounted display device helmet 10 are determined. It is expressed using a helmet coordinate system (X′Y′Z ′ coordinate system).

The camera device 2 includes a first camera device 2a and a second camera device 2b. The first camera device 2a and the second camera device 2b are different in shooting direction and are directed to the helmet 10 with a head-mounted display device, and can be viewed stereoscopically. It is installed on the ceiling of the riding body 30 via a fixed shaft so as to be separated by a certain distance (d1).
Thereby, as shown in FIG. 3, the position of the LED 7a relative to the camera device 2 is the position of the LED 7a displayed in the lighting data (image data) photographed by the first camera device 2a and the second camera device 2b. And a direction angle (α) from the first camera device 2a and a direction angle (β) from the second camera device 2b are extracted, and the distance between the first camera device 2a and the second camera device 2b is extracted. By using the distance (d1), it can be calculated by a triangulation method. The positions of the LEDs 7b and 7c, which are other optical markers, with respect to the camera device 2 are similarly calculated.
In order to be able to express the positions of the LEDs 7a, 7b, and 7c at this time in spatial coordinates, a relative coordinate system (XYZ coordinates) that is a coordinate system that is fixed to the camera device 2 and moves together with the camera device 2 is used. System). A specific origin position of the relative coordinate system (XYZ coordinate system) and description of the XYZ axis directions will be described later. The position coordinates of the LEDs 7a, 7b, 7c in the relative coordinate system (XYZ coordinate system) can be expressed as (Xa, Ya, Za), (Xb, Yb, Zb), (Xc, Yc, Zc). Thereby, the position coordinates (Xa, Ya, Za), (Xb, Yb, Zb), (Xc, Yc, Zc) of the three LEDs 7a, 7b, 7c with respect to the camera device 2 are specified, so that the LEDs 7a, 7b, The position (Xh, Yh, Zh) and angle (Θh, Φh, Ψh) of the helmet 10 with a head mounted display device to which 7c is positioned and attached are the helmet coordinates relative to the relative coordinate system (XYZ coordinate system). This can be expressed using the position and angle of the system (X′Y′Z ′ coordinate system). The angle (Θ) is the angle in the roll direction (rotation with respect to the X axis), the angle (Φ) is the angle in the elevation direction (rotation with respect to the Y axis), and the angle (Ψ) is the azimuth direction ( Angle of rotation with respect to the Z-axis). Further, the position (Xh, Yh, Zh) of the helmet 10 with a head mounted display device is the current position coordinates (Xa, Ya, Zh) of the LED 7a which is the origin of the helmet coordinate system (X′Y′Z ′ coordinate system). It is expressed by Za).

The triaxial gyro sensor 4 detects angular velocities (Vθs, Vφs, Vψs) of the vehicle 30. A coordinate system is defined for the three-axis gyro sensor itself, but it is attached with its axis accurately aligned with the relative coordinate system (XYZ coordinate system). Accordingly, angular velocities (Vθs, Vφs, Vψs) that are movements in the roll direction (rotation with respect to the X axis), the elevation direction (rotation with respect to the Y axis), and the azimuth direction (rotation with respect to the Z axis) are detected. In addition, when it is attached without being aligned, it is associated with a relative coordinate system (XYZ coordinate system) by obtaining a coordinate transformation matrix.

The control unit 20 is configured by a computer including a CPU 21, a memory 41, and the like, and performs various types of control and arithmetic processing. The processing executed by the CPU 21 will be described separately for each functional block. The optical marker driving unit 28, the relative head information calculating unit 22, the absolute moving body information calculating unit 24, the difference generating unit 23, and the video display unit. 25.
The memory 41 has an area for storing various data necessary for the control unit 20 to execute processing, a relative coordinate storage unit 43 that stores a relative coordinate system (XYZ coordinate system), Time storage unit 42, lighting data storage unit 44 that stores corrected lighting data (image data) and lighting data (image data), and extinguishing data that stores corrected extinguishing data (image data) and extinguishing data (image data) And a data storage unit 45.
4 is a time chart for explaining the flow executed by the HMT device 1, and FIG. 5 is a diagram for explaining the flow of processing the image data detected by the first camera device 2a.

Here, the relative coordinate system (XYZ coordinate system) can arbitrarily determine the origin and the direction of each coordinate axis, but in the present embodiment, as shown in FIG. 3, the second camera device 2b to the first camera device 2a. The X direction is defined as the X-axis direction, the vertical direction to the X-axis direction, the vertical direction to the ceiling, and the downward direction as the Z-axis direction, the vertical direction to the X-axis direction and the horizontal direction to the ceiling, and the rightward direction as the Y-axis direction. The origin is set in the relative coordinate storage unit 43 so as to define the origin as the midpoint between the first camera device 2a and the second camera device 2b.
Further, as described above, the lighting data storage unit 44 stores the helmet coordinate system (X′Y′Z ′ coordinate system), and further, the three LEDs 7a and 7b on the X′Y′Z ′ coordinate system. 7c (initial data) is also stored.
The time storage unit 44 stores a time t that is updated each time a light beam is detected by the camera device 2 and an angular velocity (Vθs, Vφs, Vψs) is detected by the three-axis gyro sensor 4.

The optical marker driving unit 28 outputs a command signal that causes the LED group 7 to be repeatedly turned on and off, and the lighting data of the light beam detected when the first camera device 2a and the second camera device 2b are turned on. Control is performed to detect (image data) and light extinction data (image data) of the light beam detected when the LED group 7 is extinguished.
Specifically, as shown in FIG. 4, the LED group 7 is repeatedly turned on and off at a predetermined cycle so that the lighting time width and the lighting time width are the same, and the first camera device 2a and the second camera device 2b detect the light beam with a period t which is a half of a predetermined period. Thus, for example, as shown in FIG. 5, the first camera device 2a sequentially detects the turn-off data # 1a, the turn-on data # 2a, the turn-off data # 3a, the turn-on data # 4a,. Similarly, in the second camera device 2b, the turn-off data # 1b, the turn-on data # 2b, the turn-off data # 3b, the turn-on data # 4b,. At this time, turn-off data # 1a and turn-off data # 1b, turn-on data # 2a and turn-on data # 2b, turn-off data # 3a and turn-off data # 3b, turn-on data # 4b and turn-on data # 4b, etc. are detected simultaneously. Is done.
The lighting data includes light rays emitted from the LED group 7 and disturbance light. On the other hand, the extinction data includes only ambient light.
Accordingly, since the extinguishing data includes only disturbance light, in the present embodiment, it is determined that the detected light beam is due to disturbance light. After that, when the flying object moves so that its attitude changes, the positional relationship of this disturbing light with respect to the flying object will fluctuate, so the flying will fluctuate to eliminate the influence of this disturbing light. The positional relationship of disturbance light with respect to the body is calculated.

The absolute moving body information calculation unit 24 performs control to calculate absolute moving body information including the moving angle amounts (ΔΘs, ΔΦs, ΔΨs) of the flying object with respect to disturbance light based on the angular velocities (Vθs, Vφs, Vψs). It is.
Specifically, by calculating the angular velocity (Vθs, Vφs, Vψs) from time t to time t + 1, the moving angle amounts (ΔΘs, ΔΦs, Δψs) from the flying object angle at time t are calculated. Go. That is, the moving angle amounts (ΔΘs, ΔΦs, ΔΨs) of the flying object from the time when the extinguishing data is detected by the camera device 2 to the time when the lighting data is detected are calculated.
Thus, if the moving angle amount (ΔΘs, ΔΦs, ΔΨs) of the flying object is calculated, when the flying object is at an angle of time t, the light source of disturbance light that is at an angle with respect to the flying object is , It can be seen that the flying object fluctuates from a certain angle by a moving angle amount (−ΔΘs, −ΔΦs, −ΔΨs). That is, the moving position amount (ΔX ″, ΔY ″) of the light beam due to the disturbance light on the image data detected by the camera device 2 can be calculated.

The difference generation unit 23 moves the disturbance light moving position amounts (ΔX ″, ΔY ′) on the image data detected by the camera device 2 based on the absolute moving body information including the moving angle amounts (ΔΘs, ΔΦs, ΔΨs). By calculating '), the light-on data (image data) detected when the LED group 7 is turned on creates corrected light data that corrects the position of the disturbance light, and also detects when the LED group 7 is turned off. The light extinction data (image data) is used to create the corrected light extinction data of the light beam that corrects the position of the disturbance light, and using the corrected lighting data and the corrected light extinction data, the difference data of the light from only the LED group 7 The control which produces | generates is performed.
For example, as shown in FIG. 5, the optical marker driving unit 28 detects the turn-off data # 1a, the turn-on data # 2a, the turn-off data # 3a, the turn-on data # 4a,. To go. On the other hand, the absolute moving body information calculation unit 24 sequentially calculates the moving angle amounts (ΔΘs, ΔΦs, ΔΨs) that the flying object has moved between the image data.
Therefore, the difference generation unit 23 first uses a moving angle amount (ΔΘs, ΔΦs, ΔΨs) from time t1 when the turn-off data # 1a is detected to time t2 when the turn-on data # 2a is detected, to the flying object. A moving angle amount (−ΔΘs, −ΔΦs, −ΔΨs) of the light source of disturbance light is calculated. Further, the moving position amount (ΔX ″, ΔY ″) of the light beam due to the disturbance light on the lighting data # 2a detected by the first camera device 2a is calculated. Thereby, in the lighting data # 2a, the corrected lighting data # 2a of the light beam in which the position (X ″, Y ″) of the disturbance light is corrected to (X ″ −ΔX ″, Y ″ −ΔY ″). 'Create. And the 1st difference data (# 2a '-# 1a) of the light ray radiate | emitted only from the LED group 7 is produced | generated by subtracting the extinction data # 1a from correction | amendment lighting data # 2a'.

Next, the difference generation unit 23 uses the movement angle amounts (ΔΘs, ΔΦs, ΔΨs) from the time t2 when the lighting data # 2a is detected to the time t3 when the extinguishing data # 3a is detected to disturb the flying object. The amount of movement angle of the light source (−ΔΘs, −ΔΦs, −ΔΨs) is calculated. Further, the moving position amount (ΔX ″, ΔY ″) of the light beam due to the disturbance light on the extinction data # 3a detected by the first camera device 2a is calculated. Thereby, in the extinction data # 3a, the corrected extinction data # 3a of the light beam in which the position (X ″, Y ″) of the disturbance light is corrected to (X ″ −ΔX ″, Y ″ −ΔY ″). 'Create. And the 1st difference data (# 2a- # 3a ') of the light ray radiate | emitted only from LED group 7 is produced | generated by subtracting lighting data # 2a from correction | amendment light extinction data # 3a'.
By repeating such operations, the first difference data is sequentially generated. Similarly, the second camera device 2b generates second difference data of light rays emitted only from the LED group 7. At this time, in the first difference data and the second difference data, since the disturbance light is completely removed, the position of the LED group 7 can be accurately measured.
The corrected lighting data and the lighting data are stored in the lighting data storage unit 44, and the corrected light-off data and the light-off data are stored in the light-off data storage unit 45.

Based on the difference data (first difference data and second difference data), the relative head information calculation unit 22 calculates the head position (Xh, Yh, Zh) and head of the pilot 3 with respect to the camera device 2 (relative coordinate system). Control for calculating relative head information including the component angles (Θh, Φh, Ψh) is performed.
Specifically, the position of the LED 7a with respect to the camera device 2 is obtained by extracting the position of the LED 7a displayed in the first difference data and the second difference data captured by the first camera device 2a and the second camera device 2b. Further, the direction angle (α) from the first camera device 2a and the direction angle (β) from the second camera device 2b are extracted, and the distance between the first camera device 2a and the second camera device 2b ( By using d1), it is calculated by the triangulation method. The positions of the LEDs 7b and 7c with respect to the camera device 2 are similarly calculated. At this time, since disturbance light is completely removed from the difference data (first difference data and second difference data), the position of the LED group 7 is accurately measured without erroneously recognizing the disturbance light as an LED. be able to.
Then, by comparing the calculated LED group 7 with the initial data stored in the lighting data storage unit 44, the head mounted type in which the LED group 7 is fixed to the camera device 2 (relative coordinate system). The position (Xh, Yh, Zh) and angle (Θh, Φh, Ψh) of the helmet 10 with a display device are calculated.
The video display unit 25 controls to emit video display light from the display based on the relative head information including the pilot 3 head position (Xh, Yh, Zh) and head angle (Θh, Φh, Ψh). Is to do. Thereby, the pilot 3 visually recognizes the display image by the display.

Next, a measurement operation for measuring the head position (Xh, Yh, Zh) and head angle (Θh, Φh, Ψh) of the pilot 3 with respect to the relative coordinate system (XYZ coordinate system) by the HMT device 1 will be described. 6 and 7 are flowcharts for explaining the measurement operation by the HMT apparatus 1.
First, in the process of step S101, t = t + 1 is stored in the time storage unit 42 so that the time t is updated to +1.
Next, in the process of step S <b> 102, the optical marker driving unit 28 outputs a command signal that causes the LED group 7 to be turned off, so that the LED group 7 is turned off.

Next, in the process of step S103, the optical marker driving unit 28 causes the first camera device 2a and the second camera device 2b to detect the light-off data (image data), and turns off the light-off data at t = t + 1. (Refer to # 1a and # 3a in FIG. 5). At this time, the extinction data includes only disturbance light. Note that when the extinction data at t = 0 is detected, it is determined that the detected light beam is due to disturbance light.
At the same time as executing the process of step S103, in the process of step S104, the three-axis gyro sensor 4 detects the angular velocities (Vθs, Vφs, Vψs) of the vehicle 30 from time t to time t + 1.
Next, in the process of step S105, the absolute moving body information calculation unit 24 calculates the time from the time t of the flying object to the time t + 1 to the disturbance light based on the angular velocities (Vθp, Vφp, Vψp) from the time t to the time t + 1. Absolute moving body information including movement angle amounts (ΔΘs, ΔΦs, ΔΨs) is calculated.

Next, in the process of step S106, the difference generation unit 23 uses the movement angle amounts (ΔΘs, ΔΦs, ΔΨs) to correct the position of disturbance light from the t = t + 1 extinction data, and t = t + 1 corrected extinction data. And the corrected extinction data of t = t + 1 is stored in the extinction data storage unit 45 (see # 3a ′ in FIG. 5).
Next, in step S107, it is determined whether or not lighting data of t = t is stored. When it is determined that the lighting data of t = t is not stored, the process proceeds to step S110.
On the other hand, when it is determined that the lighting data of t = t is stored, in the process of step S108, the difference generation unit 23 makes a difference between the corrected light-off data of t = t + 1 and the lighting data of t = t. Thus, difference data (first difference data and second difference data) is generated. At this time, by subtracting t = t + 1 corrected extinction data from t = t lighting data, difference data of light rays emitted only from the LED group 7 is generated (in FIG. 5, # 2a- # 3a). 'reference).

Next, in the process of step S109, the relative head information calculation unit 22 performs the first camera device 2a and the second camera device 2b (relative coordinate system) based on the difference data (first difference data and second difference data). ), The head position (Xh, Yh, Zh) and the head angle (Θh, Φh, Ψh) of the pilot 3 are calculated.
Next, in the process of step S110, t = t + 1 is stored in the time storage unit 42 so that the time t is updated to +1.
Next, in the process of step S <b> 111, the optical marker driving unit 28 outputs a command signal for lighting the LED group 7, so that the LED group 7 is lit.

Next, in the process of step S112, the optical marker driving unit 28 causes the first camera device 2a and the second camera device 2b to simultaneously detect lighting data (image data), and the lighting data storage unit stores t = t + 1 lighting data. 44. At this time, the lighting data includes light rays emitted from the LED group 7 and disturbance light (see # 2a and # 4a in FIG. 5).
At the same time as executing the process of step S112, in the process of step S113, the three-axis gyro sensor 4 detects the angular velocity (Vθs, Vφs, Vψs) of the vehicle 30 from time t to time t + 1.
Next, in the process of step S114, the absolute moving body information calculating unit 24 moves the amount of moving angle (ΔΘs, ΔΦs) from time t to time t + 1 of the flying object with respect to disturbance light based on the angular velocities (Vθs, Vφs, Vψs). , ΔΨs) is calculated.

Next, in the process of step S115, the difference generation unit 23 corrects the position of the disturbance light from the lighting data at t = t + 1 using the moving angle amounts (ΔΘs, ΔΦs, ΔΨs), and the corrected lighting data at t = t + 1. And the corrected lighting data of t = t + 1 is stored in the lighting data storage unit 44 (see # 2a ′ and # 4a ′ in FIG. 5).
Next, in the process of step S116, it is determined whether or not extinguishing data at t = t is stored. When it is determined that the extinguishing data at t = t is not stored, the process proceeds to step S119.
On the other hand, when it is determined that t = t extinguishing data is stored, in the process of step S117, the difference generating unit 23 makes a difference between the corrected lighting data of t = t + 1 and the extinguishing data of t = t. Thus, difference data (first difference data and second difference data) is generated. At this time, by subtracting t = t extinction data from the corrected lighting data of t = t + 1, difference data of light rays emitted only from the LED group 7 is generated (in FIG. 5, # 2a ′ − #). 1a and # 4a ′-# 3a).

Next, in the process of step S118, the relative head information calculation unit 22 performs the first camera device 2a and the second camera device 2b (relative coordinate system) based on the difference data (first difference data and second difference data). ), The head position (Xh, Yh, Zh) and the head angle (Θh, Φh, Ψh) of the pilot 3 are calculated.
Next, in the process of step S119, it is determined whether or not the vehicle 30 is flying. When it is determined that the vehicle 30 is flying, the process returns to step S101. In other words, the processes in steps S101 to S118 are repeated until it is determined that the vehicle 30 is not flying.
On the other hand, when it is determined that the vehicle 30 is flying, this flowchart is ended.

As described above, according to the HMT device 1, even if the position of disturbance light varies with respect to the camera device 2 attached to the vehicle 30, the disturbance light is corrected from the difference data by correcting the position of the disturbance light. Is completely removed, so that the position of the LED group 7 can be accurately measured without erroneously recognizing disturbance light as an LED.

(Other embodiments)
(1) The above-described HMT device 1 is configured to include the three-axis gyro sensor 4, but may be configured to include an acceleration sensor instead of the three-axis gyro sensor 4. In the acceleration sensor, acceleration is detected instead of angular velocity as in the case of the three-axis gyro sensor, but the moving angle amount of the flying object is calculated from the acceleration of the flying object using a general calculation method.

  The HMT device of the present invention is used as a device for measuring the position and angle of a helmet with a head-mounted display device used in, for example, game machines and vehicles.

It is a figure which shows schematic structure of the HMT apparatus which is one Embodiment of this invention. It is a top view of the helmet with a head-mounted display device shown in FIG. It is a figure for demonstrating the setting of a relative coordinate system. It is a time chart for demonstrating the flow which an HMT apparatus performs. It is a figure for demonstrating the flow which processes the image data which a 1st camera apparatus detects. It is a flowchart for demonstrating the measurement operation | movement by a HMT apparatus. It is a flowchart for demonstrating the measurement operation | movement by a HMT apparatus.

Explanation of symbols

1 Head motion tracker device 2 Camera device (optical detection means)
3 Pilot (passenger)
4 3-axis gyro sensor (moving body sensor)
7 LED group (optical marker)
DESCRIPTION OF SYMBOLS 22 Relative head information calculation part 23 Difference production | generation part 24 Absolute moving body information calculation part 28 Optical marker drive part 30 Car body

Claims (3)

An optical marker that is mounted on the passenger's head and emits light rays;
An optical detection means that is attached to a moving body on which the passenger is boarded and that can detect a light beam from the optical marker and that can be viewed stereoscopically.
A head motion tracker device comprising: a relative head information calculation unit that calculates relative head information including a head position and a head angle of a passenger with respect to the moving body based on the detected light beam;
An optical marker driving unit that causes the optical marker to repeatedly turn on and off;
A moving body sensor that is attached to the moving body and detects an angular velocity and / or acceleration acting on the moving body;
An absolute moving body information calculating unit that calculates absolute moving body information including a moving angle amount of the moving body with respect to disturbance light based on the angular velocity and / or acceleration detected from the moving body sensor;
Based on the absolute moving body information, the position of the light beam due to the disturbance light is corrected from the lighting data of the light beam detected when the optical marker is turned on by calculating the movement position amount of the light beam due to the disturbance light with respect to the optical detection means. thereby creating the compensation lighting data, said creating a compensation off data obtained by correcting the position of the light beam due to disturbance light from the off data of the detected light upon turning off of the optical markers, the correction lighting data and correction A difference generation unit that generates difference data of light rays from only the optical marker using the extinction data,
The head motion tracker device, wherein the relative head information calculation unit calculates relative head information based on the difference data. The optical marker is three or more LEDs, and
The head motion tracker device according to claim 1, wherein the optical detection unit is two or more camera devices. The head motion tracker device according to claim 1, wherein the disturbance light is sunlight.

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