Method for communicating via virtual space and system for executing the method

A method includes defining a virtual space associated with a user. The virtual space includes an avatar object associated with the user, the avatar object comprising a head and a body. The method further includes acquiring, in response to a detected rotation of a head of the user, information representing an angular velocity of the detected rotation. The method further includes determining whether the angular velocity is equal to or greater than a threshold value. The method further includes rotating, in response to a determination that the angular velocity is equal to or greater than the threshold value, the head of the avatar object without rotating the body of the avatar object.

RELATED APPLICATIONS

The present application claims priority to Japanese application No. 2017-005154, filed Jan. 16, 2017, the disclosure of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

This disclosure relates to a technology of controlling an avatar arranged in a virtual space, and more particularly, to a technology of controlling a motion by the avatar.

BACKGROUND

There is known a technology of providing virtual reality with use of a head-mounted device (HMD). There is proposed a technology of arranging respective avatars of a plurality of users in a virtual space for communication among the plurality of users via those avatars.

In order to promote communication via an avatar in such a virtual space, there has been proposed a technology for translating a motion by a user in a real space in the avatar. For example, regarding a technology of acquiring a motion by a user in a real space, in Japanese Patent Application Laid-open No. 2015-015021 (Patent Document 1), there is described a method involving “generating a three-dimensional representation of a subject by: comparing a depth image of the subject with a plurality of representative images, each representative image being associated with an individual parametric model of the subject; identifying one of the plurality of representative images as a representative image most similar to the depth image of the subject; selecting the parametric model associated with the representative image most similar to the depth image; and fitting the selected parametric model to the depth image of the subject” (see “Abstract”).

PATENT DOCUMENTS

SUMMARY

According to at least one embodiment of this disclosure, there is provided a method. The method includes defining a virtual space associated with a user, the virtual space including an avatar associated with the user, the avatar including a head and a body. The method further includes acquiring, in response to rotation of a head of the user, information representing an angular velocity of the rotation. The method further includes detecting that the angular velocity is equal to or more than a threshold value. The method further includes rotating, in response to detecting that the angular velocity is equal to or more than the threshold value, the head of the avatar without rotating the body of the avatar.

The above-mentioned and other objects, features, aspects, and advantages of the disclosure may be made clear from the following detailed description of this disclosure, which is to be understood in association with the attached drawings.

DETAILED DESCRIPTION

Now, with reference to the drawings, embodiments of this technical idea are described in detail. In the following description, like components are denoted by like reference symbols. The same applies to the names and functions of those components. Therefore, detailed description of those components is not repeated. In one or more embodiments described in this disclosure, components of respective embodiments can be combined with each other, and the combination also serves as a part of the embodiments described in this disclosure.

With reference toFIG. 1, a configuration of a head-mounted device (HMD) system100is described.FIG. 1is a diagram of a system100including a head-mounted display (HMD) according to at least one embodiment of this disclosure. The system100is usable for household use or for professional use.

The system100includes a server600, HMD sets110A,110B,110C, and110D, an external device700, and a network2. Each of the HMD sets110A,110B,110C, and110D is capable of independently communicating to/from the server600or the external device700via the network2. In some instances, the HMD sets110A,110B,110C, and110D are also collectively referred to as “HMD set110”. The number of HMD sets110constructing the HMD system100is not limited to four, but may be three or less, or five or more. The HMD set110includes an HMD120, a computer200, an HMD sensor410, a display430, and a controller300. The HMD120includes a monitor130, an eye gaze sensor140, a first camera150, a second camera160, a microphone170, and a speaker180. In at least one embodiment, the controller300includes a motion sensor420.

In at least one aspect, the computer200is connected to the network2, for example, the Internet, and is able to communicate to/from the server600or other computers connected to the network2in a wired or wireless manner. Examples of the other computers include a computer of another HMD set110or the external device700. In at least one aspect, the HMD120includes a sensor190instead of the HMD sensor410. In at least one aspect, the HMD120includes both sensor190and the HMD sensor410.

The HMD120is wearable on a head of a user5to display a virtual space to the user5during operation. More specifically, in at least one embodiment, the HMD120displays each of a right-eye image and a left-eye image on the monitor130. Each eye of the user5is able to visually recognize a corresponding image from the right-eye image and the left-eye image so that the user5may recognize a three-dimensional image based on the parallax of both of the user's the eyes. In at least one embodiment, the HMD120includes any one of a so-called head-mounted display including a monitor or a head-mounted device capable of mounting a smartphone or other terminals including a monitor.

The monitor130is implemented as, for example, a non-transmissive display device. In at least one aspect, the monitor130is arranged on a main body of the HMD120so as to be positioned in front of both the eyes of the user5. Therefore, when the user5is able to visually recognize the three-dimensional image displayed by the monitor130, the user5is immersed in the virtual space. In at least one aspect, the virtual space includes, for example, a background, objects that are operable by the user5, or menu images that are selectable by the user5. In at least one aspect, the monitor130is implemented as a liquid crystal monitor or an organic electroluminescence (EL) monitor included in a so-called smartphone or other information display terminals.

In at least one aspect, the monitor130is implemented as a transmissive display device. In this case, the user5is able to see through the HMD120covering the eyes of the user5, for example, smartglasses. In at least one embodiment, the transmissive monitor130is configured as a temporarily non-transmissive display device through adjustment of a transmittance thereof. In at least one embodiment, the monitor130is configured to display a real space and a part of an image constructing the virtual space simultaneously. For example, in at least one embodiment, the monitor130displays an image of the real space captured by a camera mounted on the HMD120, or may enable recognition of the real space by setting the transmittance of a part the monitor130sufficiently high to permit the user5to see through the HMD120.

In at least one aspect, the monitor130includes a sub-monitor for displaying a right-eye image and a sub-monitor for displaying a left-eye image. In at least one aspect, the monitor130is configured to integrally display the right-eye image and the left-eye image. In this case, the monitor130includes a high-speed shutter. The high-speed shutter operates so as to alternately display the right-eye image to the right of the user5and the left-eye image to the left eye of the user5, so that only one of the user's5eyes is able to recognize the image at any single point in time.

In at least one aspect, the HMD120includes a plurality of light sources (not shown). Each light source is implemented by, for example, a light emitting diode (LED) configured to emit an infrared ray. The HMD sensor410has a position tracking function for detecting the motion of the HMD120. More specifically, the HMD sensor410reads a plurality of infrared rays emitted by the HMD120to detect the position and the inclination of the HMD120in the real space.

In at least one aspect, the HMD sensor410is implemented by a camera. In at least one aspect, the HMD sensor410uses image information of the HMD120output from the camera to execute image analysis processing, to thereby enable detection of the position and the inclination of the HMD120.

In at least one aspect, the HMD120includes the sensor190instead of, or in addition to, the HMD sensor410as a position detector. In at least one aspect, the HMD120uses the sensor190to detect the position and the inclination of the HMD120. For example, in at least one embodiment, when the sensor190is an angular velocity sensor, a geomagnetic sensor, or an acceleration sensor, the HMD120uses any or all of those sensors instead of (or in addition to) the HMD sensor410to detect the position and the inclination of the HMD120. As an example, when the sensor190is an angular velocity sensor, the angular velocity sensor detects over time the angular velocity about each of three axes of the HMD120in the real space. The HMD120calculates a temporal change of the angle about each of the three axes of the HMD120based on each angular velocity, and further calculates an inclination of the HMD120based on the temporal change of the angles.

The eye gaze sensor140detects a direction in which the lines of sight of the right eye and the left eye of the user5are directed. That is, the eye gaze sensor140detects the line of sight of the user5. The direction of the line of sight is detected by, for example, a known eye tracking function. The eye gaze sensor140is implemented by a sensor having the eye tracking function. In at least one aspect, the eye gaze sensor140includes a right-eye sensor and a left-eye sensor. In at least one embodiment, the eye gaze sensor140is, for example, a sensor configured to irradiate the right eye and the left eye of the user5with an infrared ray, and to receive reflection light from the cornea and the iris with respect to the irradiation light, to thereby detect a rotational angle of each of the user's5eyeballs. In at least one embodiment, the eye gaze sensor140detects the line of sight of the user5based on each detected rotational angle.

The first camera150photographs a lower part of a face of the user5. More specifically, the first camera150photographs, for example, the nose or mouth of the user5. The second camera160photographs, for example, the eyes and eyebrows of the user5. A side of a casing of the HMD120on the user5side is defined as an interior side of the HMD120, and a side of the casing of the HMD120on a side opposite to the user5side is defined as an exterior side of the HMD120. In at least one aspect, the first camera150is arranged on an exterior side of the HMD120, and the second camera160is arranged on an interior side of the HMD120. Images generated by the first camera150and the second camera160are input to the computer200. In at least one aspect, the first camera150and the second camera160are implemented as a single camera, and the face of the user5is photographed with this single camera.

The microphone170converts an utterance of the user5into a voice signal (electric signal) for output to the computer200. The speaker180converts the voice signal into a voice for output to the user5. In at least one embodiment, the speaker180converts other signals into audio information provided to the user5. In at least one aspect, the HMD120includes earphones in place of the speaker180.

The controller300is connected to the computer200through wired or wireless communication. The controller300receives input of a command from the user5to the computer200. In at least one aspect, the controller300is held by the user5. In at least one aspect, the controller300is mountable to the body or a part of the clothes of the user5. In at least one aspect, the controller300is configured to output at least any one of a vibration, a sound, or light based on the signal transmitted from the computer200. In at least one aspect, the controller300receives from the user5an operation for controlling the position and the motion of an object arranged in the virtual space.

In at least one aspect, the controller300includes a plurality of light sources. Each light source is implemented by, for example, an LED configured to emit an infrared ray. The HMD sensor410has a position tracking function. In this case, the HMD sensor410reads a plurality of infrared rays emitted by the controller300to detect the position and the inclination of the controller300in the real space. In at least one aspect, the HMD sensor410is implemented by a camera. In this case, the HMD sensor410uses image information of the controller300output from the camera to execute image analysis processing, to thereby enable detection of the position and the inclination of the controller300.

In at least one aspect, the motion sensor420is mountable on the hand of the user5to detect the motion of the hand of the user5. For example, the motion sensor420detects a rotational speed, a rotation angle, and the number of rotations of the hand. The detected signal is transmitted to the computer200. The motion sensor420is provided to, for example, the controller300. In at least one aspect, the motion sensor420is provided to, for example, the controller300capable of being held by the user5. In at least one aspect, to help prevent accidently release of the controller300in the real space, the controller300is mountable on an object like a glove-type object that does not easily fly away by being worn on a hand of the user5. In at least one aspect, a sensor that is not mountable on the user5detects the motion of the hand of the user5. For example, a signal of a camera that photographs the user5may be input to the computer200as a signal representing the motion of the user5. As at least one example, the motion sensor420and the computer200are connected to each other through wired or wireless communication. In the case of wireless communication, the communication mode is not particularly limited, and for example, Bluetooth (trademark) or other known communication methods are usable.

The display430displays an image similar to an image displayed on the monitor130. With this, a user other than the user5wearing the HMD120can also view an image similar to that of the user5. An image to be displayed on the display430is not required to be a three-dimensional image, but may be a right-eye image or a left-eye image. For example, a liquid crystal display or an organic EL monitor may be used as the display430.

In at least one embodiment, the server600transmits a program to the computer200. In at least one aspect, the server600communicates to/from another computer200for providing virtual reality to the HMD120used by another user. For example, when a plurality of users play a participatory game, for example, in an amusement facility, each computer200communicates to/from another computer200via the server600with a signal that is based on the motion of each user, to thereby enable the plurality of users to enjoy a common game in the same virtual space. Each computer200may communicate to/from another computer200with the signal that is based on the motion of each user without intervention of the server600.

The external device700is any suitable device as long as the external device700is capable of communicating to/from the computer200. The external device700is, for example, a device capable of communicating to/from the computer200via the network2, or is a device capable of directly communicating to/from the computer200by near field communication or wired communication. Peripheral devices such as a smart device, a personal computer (PC), or the computer200are usable as the external device700, in at least one embodiment, but the external device700is not limited thereto.

[Hardware Configuration of Computer]

With reference toFIG. 2, the computer200in at least one embodiment is described.FIG. 2is a block diagram of a hardware configuration of the computer200according to at least one embodiment. The computer200includes, a processor210, a memory220, a storage230, an input/output interface240, and a communication interface250. Each component is connected to a bus260. In at least one embodiment, at least one of the processor210, the memory220, the storage230, the input/output interface240or the communication interface250is part of a separate structure and communicates with other components of computer200through a communication path other than the bus260.

The processor210executes a series of commands included in a program stored in the memory220or the storage230based on a signal transmitted to the computer200or in response to a condition determined in advance. In at least one aspect, the processor210is implemented as a central processing unit (CPU), a graphics processing unit (GPU), a micro-processor unit (MPU), a field-programmable gate array (FPGA), or other devices.

The memory220temporarily stores programs and data. The programs are loaded from, for example, the storage230. The data includes data input to the computer200and data generated by the processor210. In at least one aspect, the memory220is implemented as a random access memory (RAM) or other volatile memories.

The storage230permanently stores programs and data. In at least one embodiment, the storage230stores programs and data for a period of time longer than the memory220, but not permanently. The storage230is implemented as, for example, a read-only memory (ROM), a hard disk device, a flash memory, or other non-volatile storage devices. The programs stored in the storage230include programs for providing a virtual space in the system100, simulation programs, game programs, user authentication programs, and programs for implementing communication to/from other computers200. The data stored in the storage230includes data and objects for defining the virtual space.

In at least one aspect, the storage230is implemented as a removable storage device like a memory card. In at least one aspect, a configuration that uses programs and data stored in an external storage device is used instead of the storage230built into the computer200. With such a configuration, for example, in a situation in which a plurality of HMD systems100are used, for example in an amusement facility, the programs and the data are collectively updated.

The input/output interface240allows communication of signals among the HMD120, the HMD sensor410, the motion sensor420, and the display430. The monitor130, the eye gaze sensor140, the first camera150, the second camera160, the microphone170, and the speaker180included in the HMD120may communicate to/from the computer200via the input/output interface240of the HMD120. In at least one aspect, the input/output interface240is implemented with use of a universal serial bus (USB), a digital visual interface (DVI), a high-definition multimedia interface (HDMI) (trademark), or other terminals. The input/output interface240is not limited to the specific examples described above.

In at least one aspect, the input/output interface240further communicates to/from the controller300. For example, the input/output interface240receives input of a signal output from the controller300and the motion sensor420. In at least one aspect, the input/output interface240transmits a command output from the processor210to the controller300. The command instructs the controller300to, for example, vibrate, output a sound, or emit light. When the controller300receives the command, the controller300executes any one of vibration, sound output, and light emission in accordance with the command.

The communication interface250is connected to the network2to communicate to/from other computers (e.g., server600) connected to the network2. In at least one aspect, the communication interface250is implemented as, for example, a local area network (LAN), other wired communication interfaces, wireless fidelity (Wi-Fi), Bluetooth®, near field communication (NFC), or other wireless communication interfaces. The communication interface250is not limited to the specific examples described above.

In at least one aspect, the processor210accesses the storage230and loads one or more programs stored in the storage230to the memory220to execute a series of commands included in the program. In at least one embodiment, the one or more programs includes an operating system of the computer200, an application program for providing a virtual space, and/or game software that is executable in the virtual space. The processor210transmits a signal for providing a virtual space to the HMD120via the input/output interface240. The HMD120displays a video on the monitor130based on the signal.

InFIG. 2, the computer200is outside of the HMD120, but in at least one aspect, the computer200is integral with the HMD120. As an example, a portable information communication terminal (e.g., smartphone) including the monitor130functions as the computer200in at least one embodiment.

In at least one embodiment, the computer200is used in common with a plurality of HMDs120. With such a configuration, for example, the computer200is able to provide the same virtual space to a plurality of users, and hence each user can enjoy the same application with other users in the same virtual space.

According to at least one embodiment of this disclosure, in the system100, a real coordinate system is set in advance. The real coordinate system is a coordinate system in the real space. The real coordinate system has three reference directions (axes) that are respectively parallel to a vertical direction, a horizontal direction orthogonal to the vertical direction, and a front-rear direction orthogonal to both of the vertical direction and the horizontal direction in the real space. The horizontal direction, the vertical direction (up-down direction), and the front-rear direction in the real coordinate system are defined as an x axis, a y axis, and a z axis, respectively. More specifically, the x axis of the real coordinate system is parallel to the horizontal direction of the real space, the y axis thereof is parallel to the vertical direction of the real space, and the z axis thereof is parallel to the front-rear direction of the real space.

In at least one aspect, the HMD sensor410includes an infrared sensor. When the infrared sensor detects the infrared ray emitted from each light source of the HMD120, the infrared sensor detects the presence of the HMD120. The HMD sensor410further detects the position and the inclination (direction) of the HMD120in the real space, which corresponds to the motion of the user5wearing the HMD120, based on the value of each point (each coordinate value in the real coordinate system). In more detail, the HMD sensor410is able to detect the temporal change of the position and the inclination of the HMD120with use of each value detected over time.

Each inclination of the HMD120detected by the HMD sensor410corresponds to an inclination about each of the three axes of the HMD120in the real coordinate system. The HMD sensor410sets a uvw visual-field coordinate system to the HMD120based on the inclination of the HMD120in the real coordinate system. The uvw visual-field coordinate system set to the HMD120corresponds to a point-of-view coordinate system used when the user5wearing the HMD120views an object in the virtual space.

With reference toFIG. 3, the uvw visual-field coordinate system is described.FIG. 3is a diagram of a uvw visual-field coordinate system to be set for the HMD120according to at least one embodiment of this disclosure. The HMD sensor410detects the position and the inclination of the HMD120in the real coordinate system when the HMD120is activated. The processor210sets the uvw visual-field coordinate system to the HMD120based on the detected values.

InFIG. 3, the HMD120sets the three-dimensional uvw visual-field coordinate system defining the head of the user5wearing the HMD120as a center (origin). More specifically, the HMD120sets three directions newly obtained by inclining the horizontal direction, the vertical direction, and the front-rear direction (x axis, y axis, and z axis), which define the real coordinate system, about the respective axes by the inclinations about the respective axes of the HMD120in the real coordinate system, as a pitch axis (u axis), a yaw axis (v axis), and a roll axis (w axis) of the uvw visual-field coordinate system in the HMD120.

In at least one aspect, when the user5wearing the HMD120is standing (or sitting) upright and is visually recognizing the front side, the processor210sets the uvw visual-field coordinate system that is parallel to the real coordinate system to the HMD120. In this case, the horizontal direction (x axis), the vertical direction (y axis), and the front-rear direction (z axis) of the real coordinate system directly match the pitch axis (u axis), the yaw axis (v axis), and the roll axis (w axis) of the uvw visual-field coordinate system in the HMD120, respectively.

After the uvw visual-field coordinate system is set to the HMD120, the HMD sensor410is able to detect the inclination of the HMD120in the set uvw visual-field coordinate system based on the motion of the HMD120. In this case, the HMD sensor410detects, as the inclination of the HMD120, each of a pitch angle (θu), a yaw angle (θv), and a roll angle (θw) of the HMD120in the uvw visual-field coordinate system. The pitch angle (θu) represents an inclination angle of the HMD120about the pitch axis in the uvw visual-field coordinate system. The yaw angle (θv) represents an inclination angle of the HMD120about the yaw axis in the uvw visual-field coordinate system. The roll angle (θw) represents an inclination angle of the HMD120about the roll axis in the uvw visual-field coordinate system.

The HMD sensor410sets, to the HMD120, the uvw visual-field coordinate system of the HMD120obtained after the movement of the HMD120based on the detected inclination angle of the HMD120. The relationship between the HMD120and the uvw visual-field coordinate system of the HMD120is constant regardless of the position and the inclination of the HMD120. When the position and the inclination of the HMD120change, the position and the inclination of the uvw visual-field coordinate system of the HMD120in the real coordinate system change in synchronization with the change of the position and the inclination.

In at least one aspect, the HMD sensor410identifies the position of the HMD120in the real space as a position relative to the HMD sensor410based on the light intensity of the infrared ray or a relative positional relationship between a plurality of points (e.g., distance between points), which is acquired based on output from the infrared sensor. In at least one aspect, the processor210determines the origin of the uvw visual-field coordinate system of the HMD120in the real space (real coordinate system) based on the identified relative position.

With reference toFIG. 4, the virtual space is further described.FIG. 4is a diagram of a mode of expressing a virtual space11according to at least one embodiment of this disclosure. The virtual space11has a structure with an entire celestial sphere shape covering a center12in all 360-degree directions. InFIG. 4, for the sake of clarity, only the upper-half celestial sphere of the virtual space11is included. Each mesh section is defined in the virtual space11. The position of each mesh section is defined in advance as coordinate values in an XYZ coordinate system, which is a global coordinate system defined in the virtual space11. The computer200associates each partial image forming a panorama image13(e.g., still image or moving image) that is developed in the virtual space11with each corresponding mesh section in the virtual space11.

In at least one aspect, in the virtual space11, the XYZ coordinate system having the center12as the origin is defined. The XYZ coordinate system is, for example, parallel to the real coordinate system. The horizontal direction, the vertical direction (up-down direction), and the front-rear direction of the XYZ coordinate system are defined as an X axis, a Y axis, and a Z axis, respectively. Thus, the X axis (horizontal direction) of the XYZ coordinate system is parallel to the x axis of the real coordinate system, the Y axis (vertical direction) of the XYZ coordinate system is parallel to the y axis of the real coordinate system, and the Z axis (front-rear direction) of the XYZ coordinate system is parallel to the z axis of the real coordinate system.

When the HMD120is activated, that is, when the HMD120is in an initial state, a virtual camera14is arranged at the center12of the virtual space11. In at least one embodiment, the virtual camera14is offset from the center12in the initial state. In at least one aspect, the processor210displays on the monitor130of the HMD120an image photographed by the virtual camera14. In synchronization with the motion of the HMD120in the real space, the virtual camera14similarly moves in the virtual space11. With this, the change in position and direction of the HMD120in the real space is reproduced similarly in the virtual space11.

The uvw visual-field coordinate system is defined in the virtual camera14similarly to the case of the HMD120. The uvw visual-field coordinate system of the virtual camera14in the virtual space11is defined to be synchronized with the uvw visual-field coordinate system of the HMD120in the real space (real coordinate system). Therefore, when the inclination of the HMD120changes, the inclination of the virtual camera14also changes in synchronization therewith. The virtual camera14can also move in the virtual space11in synchronization with the movement of the user5wearing the HMD120in the real space.

The processor210of the computer200defines a field-of-view region15in the virtual space11based on the position and inclination (reference line of sight16) of the virtual camera14. The field-of-view region15corresponds to, of the virtual space11, the region that is visually recognized by the user5wearing the HMD120. That is, the position of the virtual camera14determines a point of view of the user5in the virtual space11.

The line of sight of the user5detected by the eye gaze sensor140is a direction in the point-of-view coordinate system obtained when the user5visually recognizes an object. The uvw visual-field coordinate system of the HMD120is equal to the point-of-view coordinate system used when the user5visually recognizes the monitor130. The uvw visual-field coordinate system of the virtual camera14is synchronized with the uvw visual-field coordinate system of the HMD120. Therefore, in the system100in at least one aspect, the line of sight of the user5detected by the eye gaze sensor140can be regarded as the line of sight of the user5in the uvw visual-field coordinate system of the virtual camera14.

[User's Line of Sight]

With reference toFIG. 5, determination of the line of sight of the user5is described.FIG. 5is a plan view diagram of the head of the user5wearing the HMD120according to at least one embodiment of this disclosure.

In at least one aspect, the eye gaze sensor140detects lines of sight of the right eye and the left eye of the user5. In at least one aspect, when the user5is looking at a near place, the eye gaze sensor140detects lines of sight R1and L1. In at least one aspect, when the user5is looking at a far place, the eye gaze sensor140detects lines of sight R2and L2. In this case, the angles formed by the lines of sight R2and L2with respect to the roll axis w are smaller than the angles formed by the lines of sight R1and L1with respect to the roll axis w. The eye gaze sensor140transmits the detection results to the computer200.

When the computer200receives the detection values of the lines of sight R1and L1from the eye gaze sensor140as the detection results of the lines of sight, the computer200identifies a point of gaze N1being an intersection of both the lines of sight R1and L1based on the detection values. Meanwhile, when the computer200receives the detection values of the lines of sight R2and L2from the eye gaze sensor140, the computer200identifies an intersection of both the lines of sight R2and L2as the point of gaze. The computer200identifies a line of sight N0of the user5based on the identified point of gaze N1. The computer200detects, for example, an extension direction of a straight line that passes through the point of gaze N1and a midpoint of a straight line connecting a right eye R and a left eye L of the user5to each other as the line of sight N0. The line of sight N0is a direction in which the user5actually directs his or her lines of sight with both eyes. The line of sight N0corresponds to a direction in which the user5actually directs his or her lines of sight with respect to the field-of-view region15.

In at least one aspect, the system100includes a television broadcast reception tuner. With such a configuration, the system100is able to display a television program in the virtual space11.

In at least one aspect, the HMD system100includes a communication circuit for connecting to the Internet or has a verbal communication function for connecting to a telephone line or a cellular service.

With reference toFIG. 6andFIG. 7, the field-of-view region15is described.FIG. 6is a diagram of a YZ cross section obtained by viewing the field-of-view region15from an X direction in the virtual space11.FIG. 7is a diagram of an XZ cross section obtained by viewing the field-of-view region15from a Y direction in the virtual space11.

InFIG. 6, the field-of-view region15in the YZ cross section includes a region18. The region18is defined by the position of the virtual camera14, the reference line of sight16, and the YZ cross section of the virtual space11. The processor210defines a range of a polar angle α from the reference line of sight16serving as the center in the virtual space as the region18.

InFIG. 7, the field-of-view region15in the XZ cross section includes a region19. The region19is defined by the position of the virtual camera14, the reference line of sight16, and the XZ cross section of the virtual space11. The processor210defines a range of an azimuth β from the reference line of sight16serving as the center in the virtual space11as the region19. The polar angle α and β are determined in accordance with the position of the virtual camera14and the inclination (direction) of the virtual camera14.

In at least one aspect, the system100causes the monitor130to display a field-of-view image17based on the signal from the computer200, to thereby provide the field of view in the virtual space11to the user5. The field-of-view image17corresponds to a part of the panorama image13, which corresponds to the field-of-view region15. When the user5moves the HMD120worn on his or her head, the virtual camera14is also moved in synchronization with the movement. As a result, the position of the field-of-view region15in the virtual space11is changed. With this, the field-of-view image17displayed on the monitor130is updated to an image of the panorama image13, which is superimposed on the field-of-view region15synchronized with a direction in which the user5faces in the virtual space11. The user5can visually recognize a desired direction in the virtual space11.

In this way, the inclination of the virtual camera14corresponds to the line of sight of the user5(reference line of sight16) in the virtual space11, and the position at which the virtual camera14is arranged corresponds to the point of view of the user5in the virtual space11. Therefore, through the change of the position or inclination of the virtual camera14, the image to be displayed on the monitor130is updated, and the field of view of the user5is moved.

While the user5is wearing the HMD120(having a non-transmissive monitor130), the user5can visually recognize only the panorama image13developed in the virtual space11without visually recognizing the real world. Therefore, the system100provides a high sense of immersion in the virtual space11to the user5.

In at least one aspect, the processor210moves the virtual camera14in the virtual space11in synchronization with the movement in the real space of the user5wearing the HMD120. In this case, the processor210identifies an image region to be projected on the monitor130of the HMD120(field-of-view region15) based on the position and the direction of the virtual camera14in the virtual space11.

In at least one aspect, the virtual camera14includes two virtual cameras, that is, a virtual camera for providing a right-eye image and a virtual camera for providing a left-eye image. An appropriate parallax is set for the two virtual cameras so that the user5is able to recognize the three-dimensional virtual space11. In at least one aspect, the virtual camera14is implemented by a single virtual camera. In this case, a right-eye image and a left-eye image may be generated from an image acquired by the single virtual camera. In at least one embodiment, the virtual camera14is assumed to include two virtual cameras, and the roll axes of the two virtual cameras are synthesized so that the generated roll axis (w) is adapted to the roll axis (w) of the HMD120.

An example of the controller300is described with reference toFIG. 8AandFIG. 8B.FIG. 8Ais a diagram of a schematic configuration of a controller according to at least one embodiment of this disclosure.FIG. 8Bis a diagram of a coordinate system to be set for a hand of a user holding the controller according to at least one embodiment of this disclosure.

In at least one aspect, the controller300includes a right controller300R and a left controller (not shown). InFIG. 8Aonly right controller300R is shown for the sake of clarity. The right controller300R is operable by the right hand of the user5. The left controller is operable by the left hand of the user5. In at least one aspect, the right controller300R and the left controller are symmetrically configured as separate devices. Therefore, the user5can freely move his or her right hand holding the right controller300R and his or her left hand holding the left controller. In at least one aspect, the controller300may be an integrated controller configured to receive an operation performed by both the right and left hands of the user5. The right controller300R is now described.

The right controller300R includes a grip310, a frame320, and a top surface330. The grip310is configured so as to be held by the right hand of the user5. For example, the grip310may be held by the palm and three fingers (e.g., middle finger, ring finger, and small finger) of the right hand of the user5.

The grip310includes buttons340and350and the motion sensor420. The button340is arranged on a side surface of the grip310, and receives an operation performed by, for example, the middle finger of the right hand. The button350is arranged on a front surface of the grip310, and receives an operation performed by, for example, the index finger of the right hand. In at least one aspect, the buttons340and350are configured as trigger type buttons. The motion sensor420is built into the casing of the grip310. When a motion of the user5can be detected from the surroundings of the user5by a camera or other device. In at least one embodiment, the grip310does not include the motion sensor420.

The frame320includes a plurality of infrared LEDs360arranged in a circumferential direction of the frame320. The infrared LEDs360emit, during execution of a program using the controller300, infrared rays in accordance with progress of the program. The infrared rays emitted from the infrared LEDs360are usable to independently detect the position and the posture (inclination and direction) of each of the right controller300R and the left controller. InFIG. 8A, the infrared LEDs360are shown as being arranged in two rows, but the number of arrangement rows is not limited to that illustrated inFIG. 8. In at least one embodiment, the infrared LEDs360are arranged in one row or in three or more rows. In at least one embodiment, the infrared LEDs360are arranged in a pattern other than rows.

The top surface330includes buttons370and380and an analog stick390. The buttons370and380are configured as push type buttons. The buttons370and380receive an operation performed by the thumb of the right hand of the user5. In at least one aspect, the analog stick390receives an operation performed in any direction of 360 degrees from an initial position (neutral position). The operation includes, for example, an operation for moving an object arranged in the virtual space11.

In at least one aspect, each of the right controller300R and the left controller includes a battery for driving the infrared ray LEDs360and other members. The battery includes, for example, a rechargeable battery, a button battery, a dry battery, but the battery is not limited thereto. In at least one aspect, the right controller300R and the left controller are connectable to, for example, a USB interface of the computer200. In at least one embodiment, the right controller300R and the left controller do not include a battery.

InFIG. 8AandFIG. 8B, for example, a yaw direction, a roll direction, and a pitch direction are defined with respect to the right hand of the user5. A direction of an extended thumb is defined as the yaw direction, a direction of an extended index finger is defined as the roll direction, and a direction perpendicular to a plane defined by the yaw-direction axis and the roll-direction axis when the user5extends his or her thumb and index finger is defined as the pitch direction.

[Hardware Configuration of Server]

With reference toFIG. 9, the server600in at least one embodiment is described.FIG. 9is a block diagram of a hardware configuration of the server600according to at least one embodiment of this disclosure. The server600includes a processor610, a memory620, a storage630, an input/output interface640, and a communication interface650. Each component is connected to a bus660. In at least one embodiment, at least one of the processor610, the memory620, the storage630, the input/output interface640or the communication interface650is part of a separate structure and communicates with other components of server600through a communication path other than the bus660.

The processor610executes a series of commands included in a program stored in the memory620or the storage630based on a signal transmitted to the server600or on satisfaction of a condition determined in advance. In at least one aspect, the processor610is implemented as a central processing unit (CPU), a graphics processing unit (GPU), a micro processing unit (MPU), a field-programmable gate array (FPGA), or other devices.

The memory620temporarily stores programs and data. The programs are loaded from, for example, the storage630. The data includes data input to the server600and data generated by the processor610. In at least one aspect, the memory620is implemented as a random access memory (RAM) or other volatile memories.

The storage630permanently stores programs and data. In at least one embodiment, the storage630stores programs and data for a period of time longer than the memory620, but not permanently. The storage630is implemented as, for example, a read-only memory (ROM), a hard disk device, a flash memory, or other non-volatile storage devices. The programs stored in the storage630include programs for providing a virtual space in the system100, simulation programs, game programs, user authentication programs, and programs for implementing communication to/from other computers200or servers600. The data stored in the storage630may include, for example, data and objects for defining the virtual space.

In at least one aspect, the storage630is implemented as a removable storage device like a memory card. In at least one aspect, a configuration that uses programs and data stored in an external storage device is used instead of the storage630built into the server600. With such a configuration, for example, in a situation in which a plurality of HMD systems100are used, for example, as in an amusement facility, the programs and the data are collectively updated.

The input/output interface640allows communication of signals to/from an input/output device. In at least one aspect, the input/output interface640is implemented with use of a USB, a DVI, an HDMI, or other terminals. The input/output interface640is not limited to the specific examples described above.

The communication interface650is connected to the network2to communicate to/from the computer200connected to the network2. In at least one aspect, the communication interface650is implemented as, for example, a LAN, other wired communication interfaces, Wi-Fi, Bluetooth, NFC, or other wireless communication interfaces. The communication interface650is not limited to the specific examples described above.

In at least one aspect, the processor610accesses the storage630and loads one or more programs stored in the storage630to the memory620to execute a series of commands included in the program. In at least one embodiment, the one or more programs include, for example, an operating system of the server600, an application program for providing a virtual space, and game software that can be executed in the virtual space. In at least one embodiment, the processor610transmits a signal for providing a virtual space to the HMD device110to the computer200via the input/output interface640.

[Control Device of HMD]

With reference toFIG. 10, the control device of the HMD120is described. According to at least one embodiment of this disclosure, the control device is implemented by the computer200having a known configuration.FIG. 10is a block diagram of the computer200according to at least one embodiment of this disclosure.FIG. 10includes a module configuration of the computer200.

InFIG. 10, the computer200includes a control module510, a rendering module520, a memory module530, and a communication control module540. In at least one aspect, the control module510and the rendering module520are implemented by the processor210. In at least one aspect, a plurality of processors210function as the control module510and the rendering module520. The memory module530is implemented by the memory220or the storage230. The communication control module540is implemented by the communication interface250.

The control module510controls the virtual space11provided to the user5. The control module510defines the virtual space11in the HMD system100using virtual space data representing the virtual space11. The virtual space data is stored in, for example, the memory module530. In at least one embodiment, the control module510generates virtual space data. In at least one embodiment, the control module510acquires virtual space data from, for example, the server600.

The control module510arranges objects in the virtual space11using object data representing objects. The object data is stored in, for example, the memory module530. In at least one embodiment, the control module510generates virtual space data. In at least one embodiment, the control module510acquires virtual space data from, for example, the server600. In at least one embodiment, the objects include, for example, an avatar object of the user5, character objects, operation objects, for example, a virtual hand to be operated by the controller300, and forests, mountains, other landscapes, streetscapes, or animals to be arranged in accordance with the progression of the story of the game.

The control module510arranges an avatar object of the user5of another computer200, which is connected via the network2, in the virtual space11. In at least one aspect, the control module510arranges an avatar object of the user5in the virtual space11. In at least one aspect, the control module510arranges an avatar object simulating the user5in the virtual space11based on an image including the user5. In at least one aspect, the control module510arranges an avatar object in the virtual space11, which is selected by the user5from among a plurality of types of avatar objects (e.g., objects simulating animals or objects of deformed humans).

The control module510identifies an inclination of the HMD120based on output of the HMD sensor410. In at least one aspect, the control module510identifies an inclination of the HMD120based on output of the sensor190functioning as a motion sensor. The control module510detects parts (e.g., mouth, eyes, and eyebrows) forming the face of the user5from a face image of the user5generated by the first camera150and the second camera160. The control module510detects a motion (shape) of each detected part.

The control module510detects a line of sight of the user5in the virtual space11based on a signal from the eye gaze sensor140. The control module510detects a point-of-view position (coordinate values in the XYZ coordinate system) at which the detected line of sight of the user5and the celestial sphere of the virtual space11intersect with each other. More specifically, the control module510detects the point-of-view position based on the line of sight of the user5defined in the uvw coordinate system and the position and the inclination of the virtual camera14. The control module510transmits the detected point-of-view position to the server600. In at least one aspect, the control module510is configured to transmit line-of-sight information representing the line of sight of the user5to the server600. In such a case, the control module510may calculate the point-of-view position based on the line-of-sight information received by the server600.

The control module510translates a motion of the HMD120, which is detected by the HMD sensor410, in an avatar object. For example, the control module510detects inclination of the HMD120, and arranges the avatar object in an inclined manner. The control module510translates the detected motion of face parts in a face of the avatar object arranged in the virtual space11. The control module510receives line-of-sight information of another user5from the server600, and translates the line-of-sight information in the line of sight of the avatar object of another user5. In at least one aspect, the control module510translates a motion of the controller300in an avatar object and an operation object. In this case, the controller300includes, for example, a motion sensor, an acceleration sensor, or a plurality of light emitting elements (e.g., infrared LEDs) for detecting a motion of the controller300.

The control module510arranges, in the virtual space11, an operation object for receiving an operation by the user5in the virtual space11. The user5operates the operation object to, for example, operate an object arranged in the virtual space11. In at least one aspect, the operation object includes, for example, a hand object serving as a virtual hand corresponding to a hand of the user5. In at least one aspect, the control module510moves the hand object in the virtual space11so that the hand object moves in association with a motion of the hand of the user5in the real space based on output of the motion sensor420. In at least one aspect, the operation object may correspond to a hand part of an avatar object.

When one object arranged in the virtual space11collides with another object, the control module510detects the collision. The control module510is able to detect, for example, a timing at which a collision area of one object and a collision area of another object have touched with each other, and performs predetermined processing in response to the detected timing. In at least one embodiment, the control module510detects a timing at which an object and another object, which have been in contact with each other, have moved away from each other, and performs predetermined processing in response to the detected timing. In at least one embodiment, the control module510detects a state in which an object and another object are in contact with each other. For example, when an operation object touches another object, the control module510detects the fact that the operation object has touched the other object, and performs predetermined processing.

In at least one aspect, the control module510controls image display of the HMD120on the monitor130. For example, the control module510arranges the virtual camera14in the virtual space11. The control module510controls the position of the virtual camera14and the inclination (direction) of the virtual camera14in the virtual space11. The control module510defines the field-of-view region15depending on an inclination of the head of the user5wearing the HMD120and the position of the virtual camera14. The rendering module520generates the field-of-view region17to be displayed on the monitor130based on the determined field-of-view region15. The communication control module540outputs the field-of-view region17generated by the rendering module520to the HMD120.

The control module510, which has detected an utterance of the user5using the microphone170from the HMD120, identifies the computer200to which voice data corresponding to the utterance is to be transmitted. The voice data is transmitted to the computer200identified by the control module510. The control module510, which has received voice data from the computer200of another user via the network2, outputs audio information (utterances) corresponding to the voice data from the speaker180.

The memory module530holds data to be used to provide the virtual space11to the user5by the computer200. In at least one aspect, the memory module530stores space information, object information, and user information.

The space information stores one or more templates defined to provide the virtual space11.

The object information stores a plurality of panorama images13forming the virtual space11and object data for arranging objects in the virtual space11. In at least one embodiment, the panorama image13contains a still image and/or a moving image. In at least one embodiment, the panorama image13contains an image in a non-real space and/or an image in the real space. An example of the image in a non-real space is an image generated by computer graphics.

The user information stores a user ID for identifying the user5. The user ID is, for example, an internet protocol (IP) address or a media access control (MAC) address set to the computer200used by the user. In at least one aspect, the user ID is set by the user. The user information stores, for example, a program for causing the computer200to function as the control device of the HMD system100.

The data and programs stored in the memory module530are input by the user5of the HMD120. Alternatively, the processor210downloads the programs or data from a computer (e.g., server600) that is managed by a business operator providing the content, and stores the downloaded programs or data in the memory module530.

In at least one embodiment, the communication control module540communicates to/from the server600or other information communication devices via the network2.

In at least one aspect, the control module510and the rendering module520are implemented with use of, for example, Unity® provided by Unity Technologies. In at least one aspect, the control module510and the rendering module520are implemented by combining the circuit elements for implementing each step of processing.

The processing performed in the computer200is implemented by hardware and software executed by the processor410. In at least one embodiment, the software is stored in advance on a hard disk or other memory module530. In at least one embodiment, the software is stored on a CD-ROM or other computer-readable non-volatile data recording media, and distributed as a program product. In at least one embodiment, the software may is provided as a program product that is downloadable by an information provider connected to the Internet or other networks. Such software is read from the data recording medium by an optical disc drive device or other data reading devices, or is downloaded from the server600or other computers via the communication control module540and then temporarily stored in a storage module. The software is read from the storage module by the processor210, and is stored in a RAM in a format of an executable program. The processor210executes the program.

With reference toFIG. 11, the control structure of the HMD set110is described.FIG. 11is a sequence chart of processing to be executed by the system100according to at least one embodiment of this disclosure.

InFIG. 11, in Step S1110, the processor210of the computer200serves as the control module510to identify virtual space data and define the virtual space11.

In Step S1120, the processor210initializes the virtual camera14. For example, in a work area of the memory, the processor210arranges the virtual camera14at the center12defined in advance in the virtual space11, and matches the line of sight of the virtual camera14with the direction in which the user5faces.

In Step S1130, the processor210serves as the rendering module520to generate field-of-view image data for displaying an initial field-of-view image. The generated field-of-view image data is output to the HMD120by the communication control module540.

In Step S1132, the monitor130of the HMD120displays the field-of-view image based on the field-of-view image data received from the computer200. The user5wearing the HMD120is able to recognize the virtual space11through visual recognition of the field-of-view image.

In Step S1134, the HMD sensor410detects the position and the inclination of the HMD120based on a plurality of infrared rays emitted from the HMD120. The detection results are output to the computer200as motion detection data.

In Step S1140, the processor210identifies a field-of-view direction of the user5wearing the HMD120based on the position and inclination contained in the motion detection data of the HMD120.

In Step S1150, the processor210executes an application program, and arranges an object in the virtual space11based on a command contained in the application program.

In Step S1160, the controller300detects an operation by the user5based on a signal output from the motion sensor420, and outputs detection data representing the detected operation to the computer200. In at least one aspect, an operation of the controller300by the user5is detected based on an image from a camera arranged around the user5.

In Step S1170, the processor210detects an operation of the controller300by the user5based on the detection data acquired from the controller300.

In Step S1180, the processor210generates field-of-view image data based on the operation of the controller300by the user5. The communication control module540outputs the generated field-of-view image data to the HMD120.

In Step S1190, the HMD120updates a field-of-view image based on the received field-of-view image data, and displays the updated field-of-view image on the monitor130.

With reference toFIG. 12AandFIG. 12B, an avatar object according to at least one embodiment is described.FIG. 12andFIG. 12Bare diagrams of avatar objects of respective users5of the HMD sets110A and110B. In the following, the user of the HMD set110A, the user of the HMD set110B, the user of the HMD set110C, and the user of the HMD set110D are referred to as “user5A”, “user5B”, “user5C”, and “user5D”, respectively. A reference numeral of each component related to the HMD set110A, a reference numeral of each component related to the HMD set110B, a reference numeral of each component related to the HMD set110C, and a reference numeral of each component related to the HMD set110D are appended by A, B, C, and D, respectively. For example, the HMD120A is included in the HMD set110A.

FIG. 12Ais a schematic diagram of HMD systems of several users sharing the virtual space interact using a network according to at least one embodiment of this disclosure. Each HMD120provides the user5with the virtual space11. Computers200A to200D provide the users5A to5D with virtual spaces11A to11D via HMDs120A to120D, respectively. InFIG. 12A, the virtual space11A and the virtual space11B are formed by the same data. In other words, the computer200A and the computer200B share the same virtual space. An avatar object6A of the user5A and an avatar object6B of the user5B are present in the virtual space11A and the virtual space11B. The avatar object6A in the virtual space11A and the avatar object6B in the virtual space11B each wear the HMD120. However, the inclusion of the HMD120A and HMD120B is only for the sake of simplicity of description, and the avatars do not wear the HMD120A and HMD120B in the virtual spaces11A and11B, respectively.

In at least one aspect, the processor210A arranges a virtual camera14A for photographing a field-of-view region17A of the user5A at the position of eyes of the avatar object6A.

FIG. 12Bis a diagram of a field of view of a HMD according to at least one embodiment of this disclosure.FIG. 12(B) corresponds to the field-of-view region17A of the user5A inFIG. 12A. The field-of-view region17A is an image displayed on a monitor130A of the HMD120A. This field-of-view region17A is an image generated by the virtual camera14A. The avatar object6B of the user5B is displayed in the field-of-view region17A. Although not included inFIG. 12B, the avatar object6A of the user5A is displayed in the field-of-view image of the user5B.

In the arrangement inFIG. 12B, the user5A can communicate to/from the user5B via the virtual space11A through conversation. More specifically, voices of the user5A acquired by a microphone170A are transmitted to the HMD120B of the user5B via the server600and output from a speaker180B provided on the HMD120B. Voices of the user5B are transmitted to the HMD120A of the user5A via the server600, and output from a speaker180A provided on the HMD120A.

The processor210A translates an operation by the user5B (operation of HMD120B and operation of controller300B) in the avatar object6B arranged in the virtual space11A. With this, the user5A is able to recognize the operation by the user5B through the avatar object6B.

FIG. 13is a sequence chart of processing to be executed by the system100according to at least one embodiment of this disclosure. InFIG. 13, although the HMD set110D is not included, the HMD set110D operates in a similar manner as the HMD sets110A,110B, and110C. Also in the following description, a reference numeral of each component related to the HMD set110A, a reference numeral of each component related to the HMD set110B, a reference numeral of each component related to the HMD set110C, and a reference numeral of each component related to the HMD set110D are appended by A, B, C, and D, respectively.

In Step S1310A, the processor210A of the HMD set110A acquires avatar information for determining a motion of the avatar object6A in the virtual space11A. This avatar information contains information on an avatar such as motion information, face tracking data, and sound data. The motion information contains, for example, information on a temporal change in position and inclination of the HMD120A and information on a motion of the hand of the user5A, which is detected by, for example, a motion sensor420A. An example of the face tracking data is data identifying the position and size of each part of the face of the user5A. Another example of the face tracking data is data representing motions of parts forming the face of the user5A and line-of-sight data. An example of the sound data is data representing sounds of the user5A acquired by the microphone170A of the HMD120A. In at least one embodiment, the avatar information contains information identifying the avatar object6A or the user5A associated with the avatar object6A or information identifying the virtual space11A accommodating the avatar object6A. An example of the information identifying the avatar object6A or the user5A is a user ID. An example of the information identifying the virtual space11A accommodating the avatar object6A is a room ID. The processor210A transmits the avatar information acquired as described above to the server600via the network2.

In Step S1310B, the processor210B of the HMD set110B acquires avatar information for determining a motion of the avatar object6B in the virtual space11B, and transmits the avatar information to the server600, similarly to the processing of Step S1310A. Similarly, in Step S1310C, the processor210C of the HMD set110C acquires avatar information for determining a motion of the avatar object6C in the virtual space11C, and transmits the avatar information to the server600.

In Step S1320, the server600temporarily stores pieces of player information received from the HMD set110A, the HMD set110B, and the HMD set110C, respectively. The server600integrates pieces of avatar information of all the users (in this example, users5A to5C) associated with the common virtual space11based on, for example, the user IDs and room IDs contained in respective pieces of avatar information. Then, the server600transmits the integrated pieces of avatar information to all the users associated with the virtual space11at a timing determined in advance. In this manner, synchronization processing is executed. Such synchronization processing enables the HMD set110A, the HMD set110B, and the HMD120C to share mutual avatar information at substantially the same timing.

Next, the HMD sets110A to110C execute processing of Step S1330A to Step S1330C, respectively, based on the integrated pieces of avatar information transmitted from the server600to the HMD sets110A to110C. The processing of Step S1330A corresponds to the processing of Step S1180ofFIG. 11.

In Step S1330A, the processor210A of the HMD set110A updates information on the avatar object6B and the avatar object6C of the other users5B and5C in the virtual space11A. Specifically, the processor210A updates, for example, the position and direction of the avatar object6B in the virtual space11based on motion information contained in the avatar information transmitted from the HMD set110B. For example, the processor210A updates the information (e.g., position and direction) on the avatar object6B contained in the object information stored in the memory module530. Similarly, the processor210A updates the information (e.g., position and direction) on the avatar object6C in the virtual space11based on motion information contained in the avatar information transmitted from the HMD set110C.

In Step S1330B, similarly to the processing of Step S1330A, the processor210B of the HMD set110B updates information on the avatar object6A and the avatar object6C of the users5A and5C in the virtual space11B. Similarly, in Step S1330C, the processor210C of the HMD set110C updates information on the avatar object6A and the avatar object6B of the users5A and5B in the virtual space11C.

[Details of Module Configuration]

With reference toFIG. 14, details of a module configuration of the computer200are described.FIG. 14is a block diagram of a configuration of modules of the computer according to at least one embodiment of this disclosure.

InFIG. 14, the control module510includes a virtual camera control module1421, a field-of-view region determination module1422, an angular velocity detection module1423, a reference line-of-sight identification module1424, a motion detection module1425, a tracking module1426, a virtual space definition module1427, a virtual object generation module1428, an operation object control module1429, and an avatar control module1431. The avatar control module1431includes a rotation control module1432. The rendering module520includes a field-of-view image generation module1433. The memory module530stores space information1434, object information1435, and user information1437. The object information1435includes the motion detection data1436.

The control module510controls image display on the monitor130of the HMD120. The virtual camera control module1421arranges the virtual camera14in the virtual space11. The virtual camera control module1421controls a position in the virtual space11at which the virtual camera14is arranged and the inclination (direction) of the virtual camera14. The field-of-view region determination module1422determines the visually-recognized region15based on the inclination of the HMD120(i.e., output of sensor190) and the position at which the virtual camera14is arranged. The field-of-view image generation module1433generates the field-of-view image17to be displayed on the monitor130based on the determined visually-recognized region15. In the following, the sensor190may also be referred to as a gyro sensor190.

The angular velocity detection module1423converts the output (e.g., voltage value) of each axis of the gyro sensor190into an angular velocity. The angular velocity detection module1423is capable of discriminating whether each axis is rotating clockwise or counterclockwise. The angular velocity detection module1423outputs the converted axial angular velocities to the virtual camera control module1421, the field-of-view region determination module1422, and the reference line-of-sight identification module1424. Those modules may identify the inclination of the HMD120based on the angular velocities input from the angular velocity detection module1423. When the gyro sensor190is capable of outputting digital data representing the angular velocities instead of analog data, the angular velocity detection module1423may be omitted from the computer200.

The reference line-of-sight identification module1424identifies the line-of-sight of the user5(i.e., inclination of the HMD120) based on the output from the gyro sensor190or the HMD sensor410. In at least one aspect, the reference line-of-sight identification module1424identifies the line-of-sight of the user5based on the signal from the eye gaze sensor140. The motion detection module1425may detect, based on the output from the HMD sensor410, a displacement amount of the HMD120relative to a reference state (e.g., origin in a global coordinate system). In at least one aspect, the displacement amount is the distance between the HMD sensor410and the HMD120.

The tracking module1426detects (tracks) the position of the hands of the user5. In this embodiment, the tracking module1426detects, based on depth information input from the first camera150, the position of the hands of the user5in a uvw visual field coordinate system set in the HMD120. More specifically, the tracking module1426detects the relative position of the hands of the user5in the uvw visual field coordinate system based on the first camera150as a reference. The first camera150and the tracking module1426may be implemented by, for example, by Leap Motion® provided by Leap Motion, Inc.

The first camera116is capable of acquiring depth information on a target object. As an example, the first camera116acquires depth information on a target object in accordance with a time-of-flight (TOF) method. As at least one example, the first camera116acquires depth information on a target object in accordance with a pattern irradiation method. In at least one embodiment of this disclosure, the first camera116is a stereo camera capable of photographing a target object from two or more different directions. The first camera116may also be a camera capable of photographing infrared rays that are invisible to people. The first camera116is mounted on the HMD120and photographs a hand of the user. The first camera116outputs the acquired hand depth information to the computer200.

The control module510controls the virtual space11provided to the user5. The virtual space definition module1427generates virtual space data representing the virtual space11, to thereby define the virtual space11in the system100.

The virtual object generation module1428generates objects to be arranged in the virtual space11. The objects may include, for example, forests, mountains, other landscapes, and animals to be arranged in accordance with the progression of the story of the game.

The operation object control module1429arranges, in the virtual space11, an operation object for receiving an operation of the user in the virtual space11. The user operates the operation object to operate an object arranged in the virtual space11, for example. In at least one aspect, the operation object includes, for example, a hand object corresponding to the hand of the user wearing the HMD120. In at least one aspect, the operation object corresponds to a hand of an avatar object described later.

The avatar control module1431generates data for arranging an avatar object of the user of another computer200, which is connected via the network, in the virtual space11. In at least one aspect, the avatar control module1431generates data for arranging an avatar object of the user5in the virtual space11. In at least one aspect, the avatar control module1431generates an avatar object simulating the user5based on an image including the user5. In at least one aspect, the avatar control module1431generates data for arranging an avatar object in the virtual space11, which is selected by the user5from among a plurality of types of avatar objects (e.g., objects simulating animals or objects of deformed humans).

In at least one aspect, in the head of the avatar object, a uvw visual field coordinate system is defined in the same manner as for the HMD120. As a result, when the inclination of the HMD120in the real space (global coordinate system) changes, the inclination of the head of the avatar object also changes accordingly.

The avatar control module1431translates the motion by the HMD120in the avatar object based on the angular velocities output by the angular velocity detection module1423. For example, the avatar control module1431generates data for rotating the head of the avatar object about the yaw axis in accordance with the angular velocity about the yaw axis input from the angular velocity detection module1423. The avatar control module1431translates, based on the output from the tracking module1426, the motion by the hands of the user in the real space in the hands of the avatar object. The avatar control module1431controls the motion by the avatar object corresponding to the user of another computer based on angular velocity information or the like input from the another computer.

When rotating the head of the avatar object about the yaw axis, the rotation control module1432determines whether or not to rotate the head of the avatar object together with the body of the avatar object. The rotation control module1432is described in more detail later.

The space information1434stores one or more templates that are defined to provide the virtual space11.

The object information1435stores content to be reproduced in the virtual space11, objects to be used in the content, and information (e.g., positional information) for arranging objects in the virtual space11. The content may include, for example, game content and content representing landscapes that resemble those of the real world.

The object information1435further includes motion detection data1436. The motion detection data1436is data representing the angular velocity about each axis of the HMD120detected by the angular velocity detection module1423, namely, the inclination of the HMD120.

FIG. 15is a table of a data structure example of the motion detection data1436according to at least one embodiment of this disclosure. The motion detection data1436stores the time and the angular velocity about each axis (pitch axis (u axis), yaw axis (v axis), and roll axis (w axis)) set in the HMD120in association with each other. This time is the timing at which the gyro sensor190detected the data (e.g., voltage value) corresponding to the angular velocities. In the example shown inFIG. 15, the angular velocity about the yaw axis (v axis) is large. This indicates that the user5has rotated his/her head about the yaw axis (v axis) in the real space.

In at least one aspect, the motion detection data1436includes, in addition to outputs from the gyro sensor190, outputs from an acceleration sensor or outputs from a geomagnetic sensor. In at least one aspect, the motion detection data1436is data representing outputs from the HMD sensor410, namely, the position and inclination of the HMD120.

Referring again toFIG. 14, the user information1437stores a program for causing the computer200to function as the control apparatus of the system100, application programs using the various content stored in the object information1435, and the like.

[Control Structure of Computer200]

A method of updating the field-of-view image in the computer200is now described with reference toFIG. 16.FIG. 16is a flowchart of processing in the system100according to at least one embodiment of this disclosure.

In Step S1610, the processor210of the computer200serves as the virtual space definition module1427to define the virtual space11.

In Step S1620, the processor210arranges the virtual camera14in the virtual space11. At this time, in a work area of the memory, the processor210may arrange the virtual camera14at the center13defined in advance in the virtual space11.

In Step S1630, the processor210serves as the field-of-view image generation module1433to generate field-of-view image data for displaying the initial field-of-view image17. The generated field-of-view image data is transmitted to the HMD120by the communication control module540via the field-of-view image generation module1433.

In Step S1632, the monitor130of the HMD120displays the field-of-view image17based on a signal received from the computer200. The user5wearing the HMD120may recognize the virtual space11through visual recognition of the field-of-view image17.

In Step S1634, the gyro sensor190detects the motion by the head of the user5(angular velocity about each axis of HMD120). The gyro sensor190outputs the detection result to the computer200.

In Step S1640, the processor210serves as the angular velocity detection module1423to calculate the angular velocity about each axis of the HMD120based on the detection result input from the gyro sensor190. Then, based on the calculated angular velocities, the processor210detects the inclination of the HMD120. The processor210also serves as the virtual camera control module1421to change the inclination of the virtual camera14(i.e., reference line-of-sight5of virtual camera14) so as to move together with the detected inclination. As a result, the field-of-view image17photographed by the virtual camera14is updated.

In Step S1650, the processor210serves as the field-of-view image generation module1433to generate field-of-view image data for displaying the field-of-view image17photographed by the virtual camera14having a changed inclination, and output the generated field-of-view image data to the HMD120.

In Step S1652, the monitor130of the HMD120displays the updated field-of-view image based on the received field-of-view image data. As a result, the field-of-view of the user in the virtual space11is updated.

FIG. 17is a diagram of the field-of-view region1717of the user5A according to at least one embodiment of this disclosure. The field-of-view region1717is an image displayed on a monitor130A of the HMD120A. This field-of-view region1717is an image generated by the virtual camera14A. The avatar object6B corresponding to the user5B is displayed in the field-of-view region1717. InFIG. 17, the avatar object6B includes a head1745B and a body1746B. Although not inFIG. 17, the avatar object6A of the user5A is similarly displayed in the field-of-view image of the user5B.

Under the state ofFIG. 17, the user5A is able to communicate to/from the user5B via the virtual space through conversation. More specifically, voice data of the user5A acquired by a microphone170A is transmitted to the HMD120B of the user5B via the server600and output from a speaker180B provided on the HMD120B. Voice data of the user5B is transmitted to the HMD120A of the user5A via the server600, and output from a speaker180A provided on the HMD120A.

As described later with reference toFIG. 19, a motion by the user5B (motion by HMD120B and motion by hand of user5B) is translated in the avatar object6B arranged in the virtual space11A by the avatar control module1431A. With this, the user5A is able to recognize the motion by the user5B through the avatar object6B.

[Control Structure of Server600]

FIG. 18is a diagram of a hardware configuration and a module configuration of the server600according to at least one embodiment of this disclosure. In at least one embodiment of this disclosure, the server600includes, as primary components, the communication interface650, the processor610, and the storage630.

The communication interface650functions as a communication module for wireless communication, which is configured to perform, for example, modulation/demodulation processing for transmitting/receiving signals to/from an external communication device, for example, the computer200. The communication interface650is implemented by, for example, a tuner or a high frequency circuit.

The processor610controls operation of the server600. The processor610executes various control programs stored in the storage630to function as a transmission/reception unit1851, a server processing unit1852, and a matching unit1853.

The transmission/reception unit1851transmits/receives various kinds of information to/from each computer200. For example, the transmission/reception unit1851transmits to each computer200a request for arranging objects in the virtual space11, a request for deleting objects from the virtual space11, a request for moving objects, voices of the user, or information for defining the virtual space11.

The server processing unit1852performs processing for a plurality of users to share the same virtual space11. For example, the server processing unit1852updates avatar object information1856described later based on the information received from the computer200.

The matching unit1853performs a series of processing steps for associating a plurality of users with one another. For example, when an input operation for the plurality of users to share the same virtual space11is performed, the matching unit1853performs, for example, processing of associating users belonging to the virtual space11to one another.

The storage630stores virtual space designation information1854, object designation information1855, the avatar object information1856, and user information1858.

The virtual space designation information1854is information to be used by the virtual space definition module1427of the computer200to define the virtual space11. For example, the virtual space designation information1854contains information for designating the size of the virtual space11and content to be developed in each mesh forming the virtual space11.

The object designation information1855designates an object to be arranged by the virtual object generation module1428of the computer200in the virtual space11.

The avatar object information1856contains inclination information1857. The inclination information1857represents an inclination of each avatar object in the virtual space11. The avatar object information1856is updated as appropriate based on information (e.g., motion detection data) input from the computer200.

The user information1858is information on the user5of the computer200. The user information1858contains, for example, identification information (e.g., user account) identifying the plurality of users5.

[Control for Translating Operation of User in Avatar Object]

With reference toFIG. 19, a method of controlling operation of an avatar object in the virtual space is described.FIG. 19is a flowchart of exchange of signals between the computer200and the server600for translating a motion by the user in the real space in the avatar object according to at least one embodiment of this disclosure. The processing illustrated inFIG. 19may be implemented by the processor210of the computer200executing a control program stored in the memory220or the storage230and the processor610of the server600executing a control program stored in the storage630.

In Step S1902, the processor610of the server600serves as the transmission/reception unit1851to transmit the virtual space designation information1854to the computers200A and200B based on requests for generating the virtual space, which are received from the computers200A and200B. At this time, each computer200may transmit identification information on the user5to the server600together with the virtual space designation information1854. Then, the processor610may serve as the matching unit1853to associate pieces of identification information on the computers200A and200B with each other to establish the fact that the users5A and5B share the same virtual space.

In Step S1904, the processor210A of the computer200A serves as a virtual space definition module1427A to define the virtual space11A based on the received virtual space designation information1854. In Step S1906, similarly to the processor210A, the processor210B of the computer200B defines the virtual space11B.

In Step S1908, the processor610outputs the object designation information1855for designating objects to be arranged in the virtual spaces11A and11B to the computers200A and200B.

In Step S1910, the processor210A serves as a virtual object generation module1428A to arrange objects in the virtual space11A based on the received object designation information1855. In Step S1912, the processor210B arranges objects in the virtual space11B similarly to the processor210A.

In Step S1914, the processor210A serves as an avatar control module1431A to arrange the avatar object6A (denoted by “own avatar object” inFIG. 22) of the user5A himself or herself in the virtual space11A. Then, the processor210A transmits information (e.g., data for modeling and positional information) on the avatar object6A to the server600.

In Step S1916, the processor610stores the received information on the avatar object6A into the storage630(avatar object information1856). The processor610further transmits the information on the avatar object6A to the computer200B sharing the same virtual space with the computer200A.

In Step S1918, the processor210B serves as an avatar control module1431B to arrange the avatar object6A in the virtual space11B based on the received information on the avatar object6A.

Similarly to Step S1914to Step S1918, in Step S1920to Step S1924, the avatar object6B is generated in the virtual spaces11A and11B (denoted by “another avatar object” inFIG. 22), and information on the avatar object6B is stored in the storage630.

In Step S1926, the processor210A serves as the angular velocity detection module1423A to detect the angular velocity about each axis of the HMD120A based on the outputs from the gyro sensor190A. The processor210A also detects the inclination of the HMD120A based on the angular velocity about each axis, and changes the inclination of the avatar object6A arranged in the virtual space11A so as to move together with this inclination. The processor210A transmits to the server600motion detection data representing the detected angular velocity about each axis of the HMD120A.

In Step S1928, the processor210B changes, in the same manner as the processor210A, the inclination of the avatar object6B arranged in the virtual space11B based on the outputs from the gyro sensor190B. The processor210B also transmits to the server600motion detection data corresponding to the outputs from the gyro sensor190B.

In Step S1930, the processor610serves as the server processing unit1852to update the inclination information1240corresponding to the avatar object6A based on the motion detection data received from the computer200A. The processor610further updates the inclination information1857corresponding to the avatar object6B based on the motion detection data received from the computer200B.

In Step S1930, the processor610further serves as the transmission/reception unit1851to transmit the motion detection data from the computer200A to the computer200B. The processor610transmits the motion detection data received from the computer200B to the computer200A.

In Step S1932, the processor210A changes the inclination of the avatar object6B arranged in the virtual space11A based on the received motion detection data. In Step S1934, the processor210B changes the inclination of the avatar object6A arranged in the virtual space11B based on the received motion detection data.

In Step S1936, the processor210A displays, on the monitor130A, an image photographed by the virtual camera14A arranged at the position of the eyes of the avatar object6A. As a result, a field-of-view image recognized by the user5A is updated. After that, the processor210A returns the processing to Step S1926.

In Step S1938, similarly to the processor210A, the processor210B displays an image photographed by the virtual camera14B on the monitor130B. With this, a field-of-view image recognized by the user5B is updated. After that, the processor210B returns the processing to Step S1928.

In at least one embodiment of this disclosure, the processing of Step S1926to S1938is executed repeatedly at an interval of, e.g., 1/60 second or 1/30 second.

Through the above-mentioned series of processing steps, the user5is able to recognize a motion by another user in the real space via the avatar object of the other user in the virtual space11.

In at least one aspect, the above-mentioned repeatedly executed processing includes processing of transmitting voices of the user5to the computer200of the partner and other processing of enhancing communication between users in the virtual space11.

In at least the example described above, in Step S1914and in Step S1920, the computer200arranges the own avatar object of the user in the virtual space11. In at least one aspect, the processing in Step S1914and in Step S1920is omitted because the user is able to communicate to/from a partner as long as the avatar object of the partner is arranged in the virtual space11.

[Rotation of Head Together with Body when Rotating Head]

FIG. 20AtoFIG. 20Care diagrams of a case in which a motion by the user5in the real space is not tracked correctly according to at least one embodiment of this disclosure. InFIG. 20A, a head2061and a body2062of the user5are facing to the right. InFIG. 20B, the head2061of the user5is facing the front, and the body2062is facing to the right. InFIG. 20C, the head2061and the body2062of the user5are facing the front.

In at least one aspect, the user5transitions from the state ofFIG. 20Ato the state ofFIG. 20B, namely, rotates his/her head2061(twists the neck) without moving the body2062. In this case, the gyro sensor190included in the HMD120detects the angular velocity (i.e., voltage value corresponding to the angular velocity) about the yaw axis (v axis). In at least one aspect, the user5transitions from the state ofFIG. 20Ato the state ofFIG. 20C, namely, rotates his/her head2061together with rotating his/her body2062(i.e., moves his/her whole body). In this case as well, the gyro sensor190detects the angular velocity about the yaw axis.

As described above, the gyro sensor190detects only the motion by the head2061of the user5, and does not detect the motion by the body2062. Therefore, a related-art computer is unable to determine, when the gyro sensor190detects the angular velocity about the yaw axis, whether the user5has transitioned from the state ofFIG. 20Ato the state ofFIG. 20B, or from the state ofFIG. 20Ato the state ofFIG. 20C. When performing this determination in a related-art computer, a new device for tracking the motion by the body2062is used. However, due to cost and location problems, adding such new devices is difficult, in some instances.

Therefore, in at least one embodiment of this disclosure, the rotation control module1432of the computer200performs the above-mentioned determination relating to the state transition based on the angular velocity about the yaw axis detected by the gyro sensor190. This control is now described in more detail.

Normally, the rotation speed of the head when rotating the head without rotating the body (i.e., when transitioning from state ofFIG. 20Ato state ofFIG. 20B) is faster than the rotation speed of the head when rotating the head together with the body (i.e., when transitioning from state ofFIG. 20Ato state ofFIG. 20C). The rotation control module1432utilizes this property to perform the above-mentioned determination regarding the state transition.

As an example, when the angular velocity about the yaw axis detected by the gyro sensor190is equal to or more than a threshold value (e.g., 360 degrees/sec), the rotation control module1432may determine that the user5has rotated his/her head without rotating his/her body. On the other hand, when the angular velocity is less than that threshold value, the rotation control module1432may determine that the user5has rotated his/her head together with his/her body.

FIG. 21is a diagram of processing of a motion by the avatar object6B in a case where the angular velocity about the yaw axis is equal to or more than the threshold value according to at least one embodiment of this disclosure.FIG. 22is a diagram of processing of a motion by the avatar object6B in a case where the angular velocity about the yaw axis is less than the threshold value according to at least one embodiment of this disclosure.

In at least one aspect, the computer200A receives from the computer200B via the server600information (motion detection data) representing the angular velocity about the yaw axis detected by the gyro sensor190B. In response to a determination that the angular velocity is equal to or more than the threshold value, as inFIG. 21, the computer200A rotates the head1745B in accordance with the angular velocity without rotating the body1746B of the avatar object6B. On the other hand, in response to a determination that the angular velocity is less than the threshold value, as inFIG. 22, the computer200A rotates the head1745B together with the body1746B of the avatar object6B in accordance with the angular velocity. As a result, the user5A is able to recognize the accurate motion by the user5B in the real space by visually recognizing the motion by the avatar object6B arranged in the virtual space11A.

Now, with reference toFIG. 23, a description is given of the above-mentioned series of control steps for determining whether or not the head and the body are to be moved together when rotating the head of the avatar object.FIG. 23is a flowchart of processing in which the computer200A controls the motion by the avatar object6B corresponding to the user5B according to at least one embodiment of this disclosure. The processing inFIG. 23may be implemented by the processor210of the computer200executing a control program stored in the memory220or the storage230.

In Step S2310, the processor210A defines the virtual space11based on the virtual space designation information1854received from the server600.

In Step S2320, the processor210A arranges the avatar object6B in the virtual space11A based on the information on the avatar object6B received from the computer200B via the server600.

In Step S2330, the processor210A receives from the computer200B via the server600information (motion detection data) representing the angular velocity about the yaw axis detected by the gyro sensor190B.

In Step S2340, the processor210A determines, as the rotation control module1432A, whether or not the angular velocity about the yaw axis is equal to or more than a threshold value determined in advance (e.g., 360 degrees/sec). The threshold value may be stored in advance in the storage230. In response to a determination that the angular velocity is equal to or more than the threshold value (YES in Step S2340), the processor210A advances the processing to Step S2350. On the other hand, in response to a determination that the angular velocity is less than the threshold value (NO in Step S2340), the processor210A advances the processing to Step S2360.

In Step S2350, the processor210A rotates the head1745B about the yaw axis in accordance with the angular velocity without rotating the body1746B of the avatar object6B. Then, the processor210A returns the processing to Step S2330.

In Step S2360, the processor210A rotates the head1745B about the yaw axis in accordance with the angular velocity together with rotating the body1746B of the avatar object6B. Then, the processor210A returns the processing to Step S2330.

In the above description, the computer200in at least one embodiment of this disclosure determines, even when the computer200does not have a device for tracking the motion by the body of the user, whether the head of the user is rotating together with the body or whether the head of the user is rotating without the body rotating. This enables the computer200to accurately translate the motion by the user in the avatar object. As a result, the user may communicate to/from another user sharing the virtual space more smoothly via an avatar object that reproduces the motion by the other user more accurately.

In the example described above, the rotation control module1432is configured to determine whether or not the head and the body of the avatar object are to be rotated together based on whether or not an angular velocity is equal to or more than a threshold value. In at least one aspect, the rotation control module1432is configured to determine whether or not the head and the body of the avatar object are to be rotated together based on whether or not an angular acceleration about the yaw axis is equal to or more than a threshold value.

[Control Using Hand Tracking Information]

In the above example, the computer200is configured to determine whether or not the head and the body of the avatar object are to be rotated together based only on the angular velocity about the yaw axis. However, there is a risk that the computer200erroneously detects the motion by the user, for example, when the user rotates his/her head very quickly while also rotating his/her body. Therefore, a control method for suppressing such an erroneous detection is now described with reference toFIG. 24toFIG. 26.

FIG. 24is a diagram of a motion by a hand at a time when the head2061moves together with the body2062according to at least one embodiment of this disclosure. InFIG. 24, there is a state in which the user5has rotated his/her head2061together with his/her body2062in the right direction as viewed from the front. At this time, a hand2066of the user5is usually rotated in the right direction as viewed from the front together with the body2062. Therefore, during the time that the user5is rotating, there is a high likelihood that the hand2066is always included in a space2065from which the first camera150arranged in the HMD120is able to acquire depth information. In other words, during the time that the head2061is rotating together with the body2062, there is a high likelihood that the computer200is able to track the position of the hand2066of the user5.

FIG. 25is a diagram of a motion by a hand at a time when the head2061moves, but the body2062does not move together with the head2061according to at least one embodiment of this disclosure. InFIG. 25, there is a state in which the user5rotates his/her head2061in the right direction as viewed from the front, without rotating the body2062therewith. At this time, the hand2066of the user5normally remains in front, and like the body2062, is not rotated. Therefore, when the head2061of the user5rotates, there is a high likelihood that the hand2066is outside the space2065. In other words, when the head2061rotates but the body2062does not, there is a high likelihood that the computer200can no longer track the position of the hand2066of the user5.

The computer200in at least one embodiment of this disclosure uses the above-mentioned property to determine whether or not the head and the body of the avatar object are to be rotated together. More specifically, when the computer200is able to track the position of the hand2066of the user5(when the first camera150is acquiring depth information on the hand2066), the computer200rotates the head of the avatar object in accordance with the angular velocity about the yaw axis detected by the gyro sensor190together with the body. On the other hand, when the computer200fails to track the position of the hand2066, the computer200rotates the head of the avatar object in accordance with the angular velocity about the yaw axis, and does not rotate the body.

FIG. 26is a flowchart of processing in which the computer200A controls the motion by the avatar object6B by using the hand tracking information according to at least one embodiment of this disclosure. Processing denoted by the same reference numerals as inFIG. 23is the same processing as inFIG. 23, and hence a description of that processing is not repeated here.

In Step S2340, in response to a determination that that the angular velocity about the yaw axis of the HMD120B received from the computer200B via the server600is equal to or more than a predetermined threshold value (YES in Step S2340), the processor210A advances the processing to Step S2610.

In Step S2610, the processor210A determines whether or not the position of the hand of the user5B is tracked. When the processor210A is receiving information (tracking data) representing the position of the hand of the user5B from the computer200B via the server600, the processor210A may determine that the position of the hand of the user5B is tracked.

In at least one aspect, when the hand of the user5B is outside the range within which the first camera150B is capable of acquiring depth information, the computer200B outputs a signal to the computer200A informing the user of that fact. The processor210A may also determine, when that signal has been received, that the position of the hand of the user5B can no longer be tracked.

In response to a determination that the position of the hand of the user5B is tracked (YES in Step S2610), the processor210A advances the processing to Step S2350. On the other hand, in response to a determination that the position of the hand of the user5B is not tracked (NO in Step S2610), the processor210A advances the processing to Step S2360.

As described above, the computer200in at least one embodiment of this disclosure is configured to determine whether or not the head and the body of the avatar object are to be rotated together by using hand tracking information in addition to the angular velocity about the yaw axis. Therefore, the computer200may suppress the erroneous detection of the motion by the user.

In at least one aspect, the computer200is configured to determine whether or not the head and the body of the avatar object are to be rotated together based only on hand tracking information. In this case, the computer200may omit the processing of Step S2340inFIG. 26, and advance the processing from Step S2330to Step S2610.

[Control Based on Rotation Angle]

In at least the embodiment described above, the computer200is configured to determine, in accordance with the angular velocity about the yaw axis of the head of the user, whether or not the head and the body of the avatar object are to be rotated together. The computer200in at least one embodiment of this disclosure performs this determination in accordance with a rotation angle, and not the angular velocity.

Now, a description is given of an outline of the above-mentioned determination control in the computer200in at least one embodiment. When the user5(person) tries to see an object arranged at a position having a yaw angle θv1from the state in which the user5is facing the front (state in which the neck is not twisted), the user may determine, in accordance with the yaw angle θv1, whether to only rotate the head or whether to rotate the whole body. Specifically, when the yaw angle θv1is large (e.g., 60 degrees or more), the user5may visually recognize an object by rotating his/her whole body (rotating head and body together). When the yaw angle θv1is small (e.g., less than 60 degrees), the user5is able to visually recognize the object by rotating only his/her head (rotating head but not rotating body).

Utilizing the above-mentioned property, the computer200in at least one embodiment rotates, in response to a determination that the rotation angle about the yaw axis of the head of the user5relative to a reference state (state in which the neck is not twisted) is less than a threshold value (e.g., 60 degrees), the head of the avatar object without rotating the body. When the rotation angle is equal to or more than the threshold value, the computer200rotates the head and the body of the avatar object together. Now, a description is given of a specific configuration and control of the computer200in at least one embodiment.

FIG. 27is a block diagram of a module configuration of the computer200according to at least one embodiment of this disclosure. Parts denoted by the same reference numerals as inFIG. 14represent the same devices or modules inFIG. 14, and hence a description of those parts is not repeated here. The hardware configuration of the computer200in at least one embodiment is the same as the hardware configuration illustrated inFIG. 2.

In addition to the configuration inFIG. 14, the computer200in at least one embodiment further includes a reference state detection module2781and a rotation angle detection module2782.

The reference state detection module2781detects a state (hereinafter also referred to as “reference state”) in which the user5is estimated as not twisting his/her neck. The reference state detection module2781stores a yaw angle (hereinafter also referred to as “reference angle”) θvs of the HMD120in the reference state in the memory11. As one example, the reference state detection module2781detects a state in which the head of the user5is substantially stationary for a period (e.g., 5 seconds) determined in advance as the reference state. The reference state detection module2781is able to determine that the head of the user5is substantially stationary when the angular velocity about the yaw axis detected by the gyro sensor190is less than a threshold value (e.g., 10 degrees/sec). Usually, the user5(person) does not maintain a twisted state for a long duration.

The rotation angle detection module2782calculates the rotation angle relative to the reference angle θvs. More specifically, the rotation angle detection module2782calculates, based on the angular velocity about the yaw axis detected by the gyro sensor190, a yaw angle θv at that time, and then calculates the difference between the yaw angle θv and the reference angle θvs as the rotation angle relative to the reference angle θvs.

FIG. 28is a flowchart of processing in which the computer200A controls the motion by the avatar object6B corresponding to the user5B according to at least one embodiment of this disclosure. Processing denoted by the same reference numerals as inFIG. 23is the same processing as inFIG. 23, and hence a description of that processing is not repeated here.

In Step S2810, the processor210A serves as the rotation angle detection module2782A to calculate the rotation angle relative to the reference state (reference angle θvs stored in memory220A) based on the angular velocity about the yaw axis received from the computer200B.

In Step S2820, the processor210A determines whether or not the rotation angle relative to the reference state (reference angle θvs) is equal to or more than a threshold value (e.g., 60 degrees). In response to a determination that the rotation angle relative to the reference state is less than the threshold value (NO in Step S2820), the processor210advances the processing to Step S2830. On the other hand, in response to a determination that the rotation angle is equal to or more than the threshold value (YES in Step S2820), the processor210advances the processing to Step S2840.

In Step S2830, the processor210A rotates, in accordance with the rotation angle relative to the reference state, the head1745B about the yaw axis without rotating the body of the avatar object6B. Then, the processor210A advances the processing to Step S2850.

In Step S2840, the processor210A rotates the head1745B of the avatar object6B about the yaw axis together with the body1746B in accordance with the rotation angle relative to the reference state.

In Step S2850, the processor210A serves as the reference state detection module2781A to determine, based on the angular velocity about the yaw axis received from the computer200B, whether or not the head of the user5B has been substantially stationary for a period determined in advance.

In response to a determination that the head of the user5B has been substantially stationary for the period determined in advance (YES in Step S2850), the processor210A advances the processing to Step S2860. On the other hand, in response to a determination that the head of the user5B has not been substantially stationary for the period determined in advance (NO in Step S2850), the processor210A returns the processing to Step S2330.

In Step S2860, the processor210A stores in the memory220the yaw angle θv of the avatar object6B at that point as the reference angle θvs. As a result, the reference state (reference angle θvs) is updated.

As described above, the computer200in at least one embodiment is able to determine, based on the rotation angle about the yaw axis of the head of another user using another computer200relative to a reference state of the another user, whether or not the head and the body of the avatar object corresponding to the another user are to be rotated together. The computer200of such at least one embodiment is also able to accurately translate in the avatar object the motion by the user.

In at least one aspect, the computer200in at least one embodiment is able to apply the above-mentioned control for suppressing erroneous detection of the motion by the user in which hand tracking information is used to the above-mentioned motion control of the avatar object based on the rotation angle.

One of ordinary skill in the art would understand that the embodiments disclosed herein are merely examples in all aspects and in no way intended to limit this disclosure. The scope of this disclosure is defined by the appended claims and not by the above description, and this disclosure encompasses all modifications made within the scope and spirit equivalent to those of the appended claims.

In the at least one embodiment described above, the description is given by exemplifying the virtual space (VR space) in which the user is immersed using an HMD. However, a see-through HMD may be adopted as the HMD. In this case, the user may be provided with a virtual experience in an augmented reality (AR) space or a mixed reality (MR) space through output of a field-of-view image that is a combination of the real space visually recognized by the user via the see-through HMD and a part of an image forming the virtual space. In this case, action may be exerted on a target object in the virtual space based on motion of a hand of the user instead of the operation object. Specifically, the processor may identify coordinate information on the position of the hand of the user in the real space, and define the position of the target object in the virtual space in connection with the coordinate information in the real space. With this, the processor can grasp the positional relationship between the hand of the user in the real space and the target object in the virtual space, and execute processing corresponding to, for example, the above-mentioned collision control between the hand of the user and the target object. As a result, an action is exerted on the target object based on motion of the hand of the user.