Artificial reality device headset DONN and DOFF detection

Aspects of the present disclosure are directed to a multi-sensor don/doff detection system for an artificial reality device headset. The multi-sensor don/doff detection system can use a combination of a proximity sensor, an inertial measurement unit (IMU), and an eye tracking/face tracking (ET/FT) unit to make these determinations. However, when both the ET/FT system and proximity sensor system are active, they can have system coexistence issues. Thus, only one of these systems can be used simultaneously. The multi-sensor don/doff detection system can more accurately identify don events by using input from the proximity sensor and the IMU. The multi-sensor don/doff detection system can also more accurately identify doff events by using input from the IMU and either A) the proximity sensor when the ET/FT system is disabled or B) the ET/FT system when the ET/FT system is enabled.

TECHNICAL FIELD

The present disclosure is directed to devices and processes that detect when an artificial reality device headset has been put on (donned) or taken off (doffed).

BACKGROUND

Artificial reality device don/doff detection can directly impact battery life and user experience. In some existing system, don/doff detection is performed using one of a proximity sensor, a capacitance sensor, or a mechanical switch. However, each of these systems are prone to false positives and false negatives due to the wide range of user and environment conditions such as eye relief range, nose height, skin tone, whether the user is wearing glasses, hair style, IPD interference, light block interference, ambient lighting, sweat or environment moisture, rapid device movement, etc. While it's possible to use a combination of don/doff detection systems, such systems can interfere with each other, causing more problems than they solve.

DETAILED DESCRIPTION

Aspects of the present disclosure are directed to a multi-sensor don/doff detection system that determines, based on inputs from multiple detection systems, when an artificial reality device headset has been donned or doffed. The multi-sensor don/doff detection system can use a combination of a proximity (“prox.”) sensor, an inertial measurement unit (IMU), and an eye tracking/face tracking (ET/FT) unit to make these determinations. However, both ET/FT sensors and proximity sensors sometimes work in the same frequency range and spatial areas, which can result in system coexistence issues (both from proximity sensor to ET/FT cameras and from illumination devices used by the ET/FT units to proximity sensors). Thus, when both the ET/FT system and proximity sensor system are active, this can result in false positive and/or false negative don/doff detections.

For example, when donning the artificial reality device headset, the multi-sensor don/doff detection system can have a false negative if the sensors are too insensitive, causing the artificial reality device headset to fail to initialize its display and disabled other systems; and the multi-sensor don/doff detection system can have a false positive if the sensors are too sensitive, causing the artificial reality device headset to turn on when the device was not actual worn, wasting battery and causing wear by unnecessarily initialize a display and other systems. Further, when doffing the artificial reality device headset, the multi-sensor don/doff detection system can have a false negative if the sensors are too insensitive, causing the artificial reality device headset to fail to turn off its display or other systems, wasting battery and causing unnecessary wear; and the multi-sensor don/doff detection system can have a false positive if the sensors are too sensitive, causing the artificial reality device headset to incorrectly turn off its display and other systems while still needed by the user.

The multi-sensor don/doff detection system can more accurately identify don events, and set a corresponding donned state variable, by using input from the proximity sensor and the IMU. These systems use low power and do not interfere with each other, and thus are ideal to be used for don detection. Further, because the ET/FT systems are not needed when the artificial reality device headset is not being worn, the ET/FT systems can be disabled so as not to interfere with the proximity sensor. The multi-sensor don/doff detection system can use input from the proximity sensor and the IMU by comparing each to a threshold, and when both are over the threshold, identifying a don event. For example, if the proximity sensor identifies an object as within 30 mm from it, for over 1 second and the IMU takes a force or angular velocity reading above a specified threshold, the don event can be identified.

The multi-sensor don/doff detection system can also more accurately identify doff events, and set a corresponding doffed state variable, by using input from the IMU and either A) the proximity sensor when the ET/FT system is disabled or B) the ET/FT system when the ET/FT system is enabled. Thus, the multi-sensor don/doff detection system uses the lower power proximity detection system when it will not be interfered with and uses the higher power ET/FT system when it is already enabled anyway (disabling the proximity sensors which may interfere with the ET/FT system). The multi-sensor don/doff detection system can use input from the proximity sensor and the IMU by identifying a doff event if either A) the proximity sensor reading does not meet a threshold for at least one second or B) the IMU reading does not meet a threshold for at least 2 minutes. The multi-sensor don/doff detection system can use input from the ET/FT system and the IMU by identifying a doff event if either A) the ET/FT system loses eye/face detection for at least one second or B) the IMU reading does not meet a threshold for at least 2 minutes.

“Virtual reality” or “VR,” as used herein, refers to an immersive experience where a user's visual input is controlled by a computing system. “Augmented reality” or “AR” refers to systems where a user views images of the real world after they have passed through a computing system. For example, a tablet with a camera on the back can capture images of the real world and then display the images on the screen on the opposite side of the tablet from the camera. The tablet can process and adjust or “augment” the images as they pass through the system, such as by adding virtual objects. “Mixed reality” or “MR” refers to systems where light entering a user's eye is partially generated by a computing system and partially composes light reflected off objects in the real world. For example, a MR headset could be shaped as a pair of glasses with a pass-through display, which allows light from the real world to pass through a waveguide that simultaneously emits light from a projector in the MR headset, allowing the MR headset to present virtual objects intermixed with the real objects the user can see. “Artificial reality,” “extra reality,” or “XR,” as used herein, refers to any of VR, AR, MR, or any combination or hybrid thereof.

Several implementations are discussed below in more detail in reference to the figures.FIG.1is a block diagram illustrating an overview of devices on which some implementations of the disclosed technology can operate. The devices can comprise hardware components of a computing system100that can detect when an artificial reality device headset has been put on (donned) or taken off (doffed) according to multiple detection systems. In various implementations, computing system100can include a single computing device103or multiple computing devices (e.g., computing device101, computing device102, and computing device103) that communicate over wired or wireless channels to distribute processing and share input data. In some implementations, computing system100can include a stand-alone headset capable of providing a computer created or augmented experience for a user without the need for external processing or sensors. In other implementations, computing system100can include multiple computing devices such as a headset and a core processing component (such as a console, mobile device, or server system) where some processing operations are performed on the headset and others are offloaded to the core processing component. Example headsets are described below in relation toFIGS.2A and2B. In some implementations, position and environment data can be gathered only by sensors incorporated in the headset device, while in other implementations one or more of the non-headset computing devices can include sensor components that can track environment or position data.

Computing system100can include one or more processor(s)110(e.g., central processing units (CPUs), graphical processing units (GPUs), holographic processing units (HPUs), etc.) Processors110can be a single processing unit or multiple processing units in a device or distributed across multiple devices (e.g., distributed across two or more of computing devices101-103).

Computing system100can include one or more input devices120that provide input to the processors110, notifying them of actions. The actions can be mediated by a hardware controller that interprets the signals received from the input device and communicates the information to the processors110using a communication protocol. Each input device120can include, for example, a mouse, a keyboard, a touchscreen, a touchpad, a wearable input device (e.g., a haptics glove, a bracelet, a ring, an earring, a necklace, a watch, etc.), a camera (or other light-based input device, e.g., an infrared sensor), a microphone, or other user input devices.

In some implementations, input from the I/O devices140, such as cameras, depth sensors, IMU sensor, GPS units, LiDAR or other time-of-flights sensors, etc. can be used by the computing system100to identify and map the physical environment of the user while tracking the user's location within that environment. This simultaneous localization and mapping (SLAM) system can generate maps (e.g., topologies, girds, etc.) for an area (which may be a room, building, outdoor space, etc.) and/or obtain maps previously generated by computing system100or another computing system that had mapped the area. The SLAM system can track the user within the area based on factors such as GPS data, matching identified objects and structures to mapped objects and structures, monitoring acceleration and other position changes, etc.

Computing system100can include a communication device capable of communicating wirelessly or wire-based with other local computing devices or a network node. The communication device can communicate with another device or a server through a network using, for example, TCP/IP protocols. Computing system100can utilize the communication device to distribute operations across multiple network devices.

The processors110can have access to a memory150, which can be contained on one of the computing devices of computing system100or can be distributed across of the multiple computing devices of computing system100or other external devices. A memory includes one or more hardware devices for volatile or non-volatile storage, and can include both read-only and writable memory. For example, a memory can include one or more of random access memory (RAM), various caches, CPU registers, read-only memory (ROM), and writable non-volatile memory, such as flash memory, hard drives, floppy disks, CDs, DVDs, magnetic storage devices, tape drives, and so forth. A memory is not a propagating signal divorced from underlying hardware; a memory is thus non-transitory. Memory150can include program memory160that stores programs and software, such as an operating system162, multi-sensor don/doff detection system164, and other application programs166. Memory150can also include data memory170that can include IMU readings, proximity sensor readings, ET/FT readings, reading thresholds for don and doff detection, ET/FT status identifiers, don/doff state identifiers, configuration data, settings, user options or preferences, etc., which can be provided to the program memory160or any element of the computing system100.

FIG.2Ais a wire diagram of a virtual reality head-mounted display (HMD)200, in accordance with some embodiments. The HMD200includes a front rigid body205and a band210. The front rigid body205includes one or more electronic display elements of an electronic display245, an inertial measurement unit (IMU)215, one or more position sensors220, locators225, and one or more compute units230. The position sensors220, the IMU215, and compute units230may be internal to the HMD200and may not be visible to the user. In various implementations, the IMU215, position sensors220, and locators225can track movement and location of the HMD200in the real world and in an artificial reality environment in three degrees of freedom (3DoF) or six degrees of freedom (6DoF). For example, the locators225can emit infrared light beams which create light points on real objects around the HMD200. As another example, the IMU215can include e.g., one or more accelerometers, gyroscopes, magnetometers, other non-camera-based position, force, or orientation sensors, or combinations thereof. One or more cameras (not shown) integrated with the HMD200can detect the light points. Compute units230in the HMD200can use the detected light points to extrapolate position and movement of the HMD200as well as to identify the shape and position of the real objects surrounding the HMD200.

The electronic display245can be integrated with the front rigid body205and can provide image light to a user as dictated by the compute units230. In various embodiments, the electronic display245can be a single electronic display or multiple electronic displays (e.g., a display for each user eye). Examples of the electronic display245include: a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, an active-matrix organic light-emitting diode display (AMOLED), a display including one or more quantum dot light-emitting diode (QOLED) sub-pixels, a projector unit (e.g., microLED, LASER, etc.), some other display, or some combination thereof.

In some implementations, the HMD200can be coupled to a core processing component such as a personal computer (PC) (not shown) and/or one or more external sensors (not shown). The external sensors can monitor the HMD200(e.g., via light emitted from the HMD200) which the PC can use, in combination with output from the IMU215and position sensors220, to determine the location and movement of the HMD200.

FIG.2Bis a wire diagram of a mixed reality HMD system250which includes a mixed reality HMD252and a core processing component254. The mixed reality HMD252and the core processing component254can communicate via a wireless connection (e.g., a 60 GHz link) as indicated by link256. In other implementations, the mixed reality system250includes a headset only, without an external compute device or includes other wired or wireless connections between the mixed reality HMD252and the core processing component254. The mixed reality HMD252includes a pass-through display258and a frame260. The frame260can house various electronic components (not shown) such as light projectors (e.g., LASERs, LEDs, etc.), cameras, eye-tracking sensors, MEMS components, networking components, etc.

The projectors can be coupled to the pass-through display258, e.g., via optical elements, to display media to a user. The optical elements can include one or more waveguide assemblies, reflectors, lenses, mirrors, collimators, gratings, etc., for directing light from the projectors to a user's eye. Image data can be transmitted from the core processing component254via link256to HMD252. Controllers in the HMD252can convert the image data into light pulses from the projectors, which can be transmitted via the optical elements as output light to the user's eye. The output light can mix with light that passes through the display258, allowing the output light to present virtual objects that appear as if they exist in the real world.

Similarly to the HMD200, the HMD system250can also include motion and position tracking units, cameras, light sources, etc., which allow the HMD system250to, e.g., track itself in 3DoF or 6DoF, track portions of the user (e.g., hands, feet, head, or other body parts), map virtual objects to appear as stationary as the HMD252moves, and have virtual objects react to gestures and other real-world objects.

FIG.2Cillustrates controllers270, which, in some implementations, a user can hold in one or both hands to interact with an artificial reality environment presented by the HMD200and/or HMD250. The controllers270can be in communication with the HMDs, either directly or via an external device (e.g., core processing component254). The controllers can have their own IMU units, position sensors, and/or can emit further light points. The HMD200or250, external sensors, or sensors in the controllers can track these controller light points to determine the controller positions and/or orientations (e.g., to track the controllers in 3DoF or 6DoF). The compute units230in the HMD200or the core processing component254can use this tracking, in combination with IMU and position output, to monitor hand positions and motions of the user. The controllers can also include various buttons (e.g., buttons272A-F) and/or joysticks (e.g., joysticks274A-B), which a user can actuate to provide input and interact with objects.

FIG.2Dis a wire diagram illustrating a second view of the artificial reality device headset280which can be used in some implementations of the present technology. In some implementations, the artificial reality device headset280is the same as, or shares components with, the virtual reality HMD200or the mixed reality HMD system250. The artificial reality device headset280can include lenses282A and282B. The artificial reality device headset280can include a proximity sensor284, which can emit a beam, such as infrared light, and detect how the beam rebounds off a target to get the distance to that target. The artificial reality device headset280can include an eye tracking face tracking (ET/FT) system, including ET/FT cameras286A-286E. In some implementations, these ET/FT cameras can run at 72 Hz or 90 Hz. One or more light sources can illuminate either or both of the user's eyes in front of the lenses282and the ET/FT cameras can capture a reflection of this light to determine eye position (e.g., based on set of reflections around the user's cornea), modeling the user's eye and determining a gaze direction. The ET/FT cameras286can also capture portions of the user's face to detect, e.g., facial expressions.

In various implementations, the HMD200,250, or artificial reality device headset can also include additional subsystems, such as an audio system, various network components, etc., to monitor indications of user interactions and intentions. For example, in some implementations, instead of or in addition to controllers, one or more cameras included in the HMD200, HMD250, or artificial reality device headset280or from external cameras, can monitor the positions and poses of the user's hands to determine gestures and other hand and body motions.

FIG.3is a block diagram illustrating an overview of an environment300in which some implementations of the disclosed technology can operate. Environment300can include one or more client computing devices305A-D, examples of which can include computing system100. In some implementations, some of the client computing devices (e.g., client computing device305B) can be the HMD200or the HMD system250. Client computing devices305can operate in a networked environment using logical connections through network330to one or more remote computers, such as a server computing device.

In some implementations, server310can be an edge server which receives client requests and coordinates fulfillment of those requests through other servers, such as servers320A-C. Server computing devices310and320can comprise computing systems, such as computing system100. Though each server computing device310and320is displayed logically as a single server, server computing devices can each be a distributed computing environment encompassing multiple computing devices located at the same or at geographically disparate physical locations.

Client computing devices305and server computing devices310and320can each act as a server or client to other server/client device(s). Server310can connect to a database315. Servers320A-C can each connect to a corresponding database325A-C. As discussed above, each server310or320can correspond to a group of servers, and each of these servers can share a database or can have their own database. Though databases315and325are displayed logically as single units, databases315and325can each be a distributed computing environment encompassing multiple computing devices, can be located within their corresponding server, or can be located at the same or at geographically disparate physical locations.

Network330can be a local area network (LAN), a wide area network (WAN), a mesh network, a hybrid network, or other wired or wireless networks. Network330may be the Internet or some other public or private network. Client computing devices305can be connected to network330through a network interface, such as by wired or wireless communication. While the connections between server310and servers320are shown as separate connections, these connections can be any kind of local, wide area, wired, or wireless network, including network330or a separate public or private network.

FIG.4is a block diagram illustrating components400which, in some implementations, can be used in a system employing the disclosed technology. Components400can be included in one device of computing system100or can be distributed across multiple of the devices of computing system100. The components400include hardware410, mediator420, and specialized components430. As discussed above, a system implementing the disclosed technology can use various hardware including processing units412, working memory414, input and output devices416(e.g., cameras, displays, IMU units, network connections, etc.), and storage memory418. In various implementations, storage memory418can be one or more of: local devices, interfaces to remote storage devices, or combinations thereof. For example, storage memory418can be one or more hard drives or flash drives accessible through a system bus or can be a cloud storage provider (such as in storage315or325) or other network storage accessible via one or more communications networks. In various implementations, components400can be implemented in a client computing device such as client computing devices305or on a server computing device, such as server computing device310or320.

Mediator420can include components which mediate resources between hardware410and specialized components430. For example, mediator420can include an operating system, services, drivers, a basic input output system (BIOS), controller circuits, or other hardware or software systems.

Specialized components430can include software or hardware configured to perform operations for determining, based on inputs from multiple detection systems, when an artificial reality device headset has been donned or doffed. Specialized components430can include a proximity sensing system434, an IMU system436, an ET/FT system438, a don/doff state tracking system440, and components and APIs which can be used for providing user interfaces, transferring data, and controlling the specialized components, such as interfaces432. In some implementations, components400can be in a computing system that is distributed across multiple computing devices or can be an interface to a server-based application executing one or more of specialized components430. Although depicted as separate components, specialized components430may be logical or other nonphysical differentiations of functions and/or may be submodules or code-blocks of one or more applications.

The proximity sensing system434can interact with a proximity sensor of I/O416to get proximity sensor readings and can compare these readings to a proximity don threshold or a proximity doff threshold (which may be the same or different thresholds), and report the comparison result to the don/doff state tracking system440. Proximity sensing system434can also disable the proximity sensor of I/O416when the ET/FT system438indicates the ET/FT devices of I/O416are enabled and enable the proximity sensor of I/O416when the ET/FT system438indicates the ET/FT devices of I/O416are disabled. Additional details on tracking proximity sensing readings as compared to thresholds and controlling the proximity sensors status are provided below in relation to blocks502and510ofFIG.5.

The IMU system436can interact with a IMU system of I/O416to get IMU readings and can compare these readings to an IMU don threshold or an IMU doff threshold (which may be the same or different thresholds), and report the comparison result to the don/doff state tracking system440. Additional details on tracking IMU readings as compared to thresholds are provided below in relation to blocks502,508, and510ofFIG.5.

The ET/FT system438can interact with ET/FT devices of I/O416to get ET/FT status readings and can compare how long these readings are in a given state (eye detected, eye not detected, face detected, face not detected) to an ET/FT timing doff threshold and report the comparison result to the don/doff state tracking system440. ET/FT system438can also disable and enable the ET/FT devices of I/O416, e.g., in response to these systems being indicated as used by a current application. Additional details on tracking ET/FT state readings as compared to a timing threshold and controlling the ET/FT devices are provided below in relation to blocks506and508ofFIG.5.

The don/doff state tracking system440can track whether the artificial reality device headset is being worn by a user (i.e., in a donned state) or is not being worn by a user (i.e., in a doffed state).

When in the doffed state, don/doff state tracking system440can get the proximity threshold comparison from the proximity sensing system434and can get the IMU to don threshold comparison from the IMU system436and, if both comparisons evaluate to true, can set the don/doff state to the donned state.

When in the donned state and the ET/FT system438indicates the ET/FT devices are enabled, don/doff state tracking system440can get the ET/FT timing comparison from the ET/FT system438and can get the IMU to doff threshold comparison from the IMU system436, and if either comparison evaluates to true, can set the don/doff state to the doffed state.

When in the donned state and the ET/FT system438indicates the ET/FT devices are disabled, don/doff state tracking system440can get the proximity threshold comparison from the proximity sensing system434and can get the IMU to doff threshold comparison from the IMU system436, and if either comparison evaluates to true, can set the don/doff state to the doffed state.

FIG.5is a flow diagram illustrating a process500used in some implementations of the present technology for setting an artificial reality device headset's (“headset”) don or doff state according to a combination of two of an IMU sensor, a proximity sensor, and an eye tracking/face tracking system. Process500can be performed by an artificial reality device, e.g., as a sub-process of an operating system of the artificial reality device. In some implementations, process500can start, when the headset is in a doffed state, at block502. In other implementations, process500can start, when the headset is in a donned state, at block506instead.

At block502, process500can determine whether a current set of readings from the proximity sensor are above a proximity don threshold and whether a current set of readings from the IMU are above an IMU don threshold. The readings from the proximity sensor can be above the proximity don threshold when they indicate there is an object (i.e., the user's face) within 30 mm of the proximity sensor for at least one second. The readings from the IMU can be above the IMU don threshold when a movement above a threshold force or above an angular velocity is measured. If both the current set of readings from the proximity sensor are above the proximity don threshold and the current set of readings from the IMU are above the IMU don threshold, process500can continue to block504; otherwise process500can stay at block502.

At block504, process500can set an artificial reality device headset to a donned state. This can include, for example, setting an environment variable, defined in the operating system of the artificial reality device headset, to a value corresponding to the headset being donned.

At block506, process500can determine whether an ET/FT system is active. This can be accomplished by checking whether hardware (through status indicators in the operating system or other control system) of the ET/FT system is emitting light and/or capturing light or by checking wither any current application executing on the artificial reality device uses the ET/FT system and therefore has enabled it. If the ET/FT system is active, process500can proceed to block508; otherwise process500can proceed to block510.

At block508, process500can determine if either the ET/FT system doesn't recognize a face or eye for a threshold amount of time (e.g., 1 second) or if all readings from the IMU are below an IMU doff threshold for an amount of time (e.g., 2 minutes). If neither is true, process500can return to block506. If either is true, process500can proceed to block512.

At block510, process500can determine if either a current set of readings from the proximity sensor are below a proximity doff threshold (e.g., no measurement of an object within 30 mm) for a threshold amount of time (e.g., 1 second) or if all readings from the IMU are below an IMU doff threshold for an amount of time (e.g., 2 minutes). If neither is true, process500can return to block506. If either is true, process500can proceed to block512.

At block512, process500can set the artificial reality device headset to a doffed state. This can include, for example, setting an environment variable, defined in the operating system of the artificial reality device headset, to a value corresponding to the headset being doffed. Process500can repeat while the headset is powered on, returning to block502.