BACKGROUND

[0001] Extended reality (XR) technologies include virtual reality (VR), augmented reality (AR), and mixed reality (MR) technologies, and quite literally extend the reality that users experience. XR technologies may employ head- mountable displays (HMDs) or near-eye devices (NEDs), for instance. An HMD is a display device that can be worn on the head. In VR technologies, the HMD wearer is immersed in an entirely virtual world, whereas in AR technologies, the HMD wearer’s direct or indirect view of the physical, real-world environment is augmented. In MR, or hybrid reality, technologies, the HMD wearer experiences the merging of real and virtual worlds.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] FIGs. 1 A and 1 B are side view diagrams of an example head- mountable display (HMD) device in which a headband assembly of the device has been rotated in different positions relative to an HMD body of the device, in correspondence with different usage modes of the HMD device.

[0003] FIG. 2 is a side view diagram of an example portion of an HMD device in detail, illustrating a mechanical mount feature that rotatably attaches a headband assembly of the device to an HMD body of the device. [0004] FIGs. 3A, 3B, 3C, 3D, and 3E are diagrams of an example rotatably attaching mechanical mount feature of an HMD device, as a headband assembly of the device is rotated relative to an HMD body of the device. [0005] FIGs. 4A and 4B are side view diagrams of an example HMD device in which a headband assembly of the device has been rotated in other positions relative to an HMD body of the device, in correspondence with other usage modes of the HMD device. [0006] FIG. 5 is a block diagram of an example HMD device.

[0007] FIG. 6 is a block diagram of an example rotatably attaching mechanical mount feature.

[0008] FIG. 7 is a flowchart of an example method for using an

HMD device. DETAILED DESCRIPTION

[0009] As noted in the background, a head-mountable display (HMD) can be employed as an extended reality (XR) technology to extend the reality experienced by the HMD’s wearer. An HMD can include a small display in front of both eyes or one or each eye of the wearer, as well as various sensors to detect or sense the wearer and/or the wearer’s environment so that the images projected on the HMD’s display convincingly immerse the wearer within an XR, be it a virtual reality (VR), augmented reality (AR), a mixed reality (MR), or another type of XR. An HMD may include speakers, which may be disposed on earpieces positioned against the HMD wearer’s ears. [0010] An HMD can include a headband so that the HMD can be securely attached to its wearer’s head and thus used in a hands-free manner. There may be one headband that is adjustably fitted against the top of the wearer’s head, and another headband that is adjustably fitted against the back of the wearer’s head. Such secure attachment to the wearer’s head ensures that the HMD does not inadvertently fall off the user or become misadjusted during regular hands free usage of the HMD. This can be of particular importance for gaming applications, for instance, in which it is not uncommon for the wearer to move his or her head about rapidly in changing directions.

[0011] While HMDs may be designed for hands-free usage, in some situations such hands-free usage may not be wanted. For instance, in demonstration-oriented situations like tradeshows and conventions, many users may wish to try out an HMD for short periods of time without having to first put on the HMD and adjust the headbands. Rather, a user may wish to hold the HMD and manually maintain the HMD against his or her face to briefly try out the HMD. A developer may similarly want to briefly use an HMD to verify proper operation of an HMD application undergoing development. Individuals may also not wish to wear an HMD for religious, cultural, or other reasons. [0012] However, the headband of an HMD may make it difficult for a user to manually maintain the HMD against the user’s face with either or both hands, by getting in the way when the user positions the HMD against his or her face. This issue may particularly occur with an HMD having rigid temples akin to a pair of eyeglasses to which a top and/or back headband is secured. While the headbands may be removable so as not to impede the user from manually maintaining the HMD against his or her face, the headbands in such instance are more apt to be misplaced, and their removal and subsequent reattachment may be inconvenient if not time consuming. [0013] Techniques described herein ameliorate these and other issues via a rotatably attaching mechanical mount feature. An HMD device can include an HMD body positionable against a face of a user opposite the user’s eyes, as well as a headband assembly including a headband securable to the user’s head. The HMD device includes a mechanical mount feature that rotatably attaches the headband assembly to the HMD body. The headband assembly is thus rotatable relative to the HMD body among different positions corresponding to multiple usage modes of the HMD device.

[0014] For instance, the headband assembly may be rotatable to a position behind the HMD body so that the HMD device can be used in a hands free usage mode in which the user secures the headband to his or her head to wear the device. The headband assembly may be rotatable to a position above the HMD body so that the HMD device can be used in an assisted usage mode in which the user manually continually maintains the HMD body against his or her face, without interference from the headband. The headband assembly may be rotatable to various positions corresponding to various usage modes as well. [0015] FIGs. 1 A and 1 B show side views of an example HMD device 100. The HMD device 100 includes an HMD body 102 and a headband assembly 104. The HMD body 102 can include a face gasket 106 that is positioned against a user’s face opposite his or her eyes so that the user can view a display internally mounted at an end 108 of the HMD body 102. The headband assembly 104 can include back and top headbands 110 and 112 that are adjustably fittable against the back and top of the user’s head, respectively, and which themselves can be of a flexible material. The headband assembly 104 can further include an earpiece 114 having a speaker, for either or both of the user’s ears. A portion of the headband assembly 104 can be rigid, and another portion (e.g., including the headbands 110 and 112) may be semi-rigid or flexible. [0016] The headband assembly 104 is rotatable relative to the HMD body

102 among positions corresponding to multiple usage modes of the HMD device 100. In FIG. 1A, the headband assembly 104 has been rotated to a position behind the HMD body 102, permitting the headbands 110 and 112 to be secured to the user’s head. The position of the headband assembly 104 relative to the HMD body 102 in FIG. 1 A thus corresponds to a usage mode in which the user can wear - and therefore use - the HMD device 100 in a hands-free manner. [0017] The headband assembly 104 is more specifically considered as fully rotated behind the HMD body 102 in FIG. 1A. That is, at this position, clockwise rotation of the headband assembly 104 relative to the HMD body 102 raises the headband assembly 102 above horizontal relative to the HMD body 102 in FIG. 1A. Furthermore, at this position, counter-clockwise rotation of the headband assembly 104 relative to the HMD body 104 lowers the headband assembly 102 below horizontal relative to the HMD body 102 in FIG. 1A. Stated another way, at this position, both clockwise and counter-clockwise rotation of the headband assembly 104 relative to the HMD body 102 results in the left end of the headband assembly 104 in FIG. 1 A being rotated closer to the end 108 of HMD body 102. [0018] In FIG. 1B, the headband assembly 104 has been rotated to a position fully above the HMD body 102, preventing the headbands 110 and 112 from being secured to the user’s head. This position corresponds to a usage mode in which the HMD device 100 is not worn by the user, but can still be used by the user manually maintaining the HMD body 102 against his or her face (e.g., without the support of the headbands 110 and 112). For instance, the user may hold the HMD body 102 in either or both hands and, while using the HMD device 100, continuously place the HMD body 102 against his or her face so that the face gasket 106 is positioned opposite the user’s eyes. [0019] The headband assembly 104 is more specifically considered as fully rotated above the HMD body 102 in FIG. 1B. That is, at this position, clockwise rotation of the headband assembly 104 relative to the HMD body 102 lowers the headband assembly 102 relative to the HMD body 102. Likewise, at this position, counter-clockwise rotation of the headband assembly 104 relative to the HMD body 104 also lowers the headband assembly 102 below horizontal relative to the HMD body 102. Stated another way, at this position, both clockwise and counter-clockwise rotation of the headband assembly 104 relative to the HMD body 102 results in lowering of the headband assembly 104 relative to the HMD body 102 in FIG. 1 B. [0020] Rotation of the headband assembly 104 relative to the HMD body

102 to a position above the HMD body 102, as in FIG. 1B, inhibits the headband assembly 104 from interfering with the user’s ability to manually maintain the HMD body 102 against his or her face. By comparison, if the user were to attempt to place the HMD body 102 against the face while the headband assembly 104 is rotated behind the HMD body 102, as in FIG. 1A, the headbands 110 and 1120 assembly 104 could get in the way unless the user inserts his or her head between the headbands 110 and 112 and the HMD body 102. However, the headbands 110 and 112 may first have to be loosened before the user’s head could fit, impeding quickly using the HMD device 100 in an assisted usage mode.

[0021] FIG. 2 shows an example portion of the HMD device 100 in detail, specifically in the case in which the headband assembly 104 has been rotated to a position behind the HMD body 102 as in FIG. 1 A. In FIG. 2, a cover of the headband assembly 104 has been removed to reveal a mechanical mount feature 200. The mechanical mount feature 200 rotatably attaches the headband assembly 104 to the HMD body 102. In this manner, the mechanical mount feature 200 may be considered a rotatable attachment feature in that the mechanical mount feature 200 attaches components together to permit the components to rotate relative to one another. In the example of FIG. 2, the mechanical mount feature 200 permits the headband assembly 104 to rotate relative to the HMD body 102 between the positions of FIGs. 1A and FIG. 1B. [0022] FIGs. 3A-3E show the example mechanical mount feature 200 as the headband assembly 104 is rotated from the position behind the HMD body 102 as in FIG. 1A to the position above the HMD body 102 as in FIG. 1B. The mechanical mount feature 200 includes posts 302 on the HMD body 102 movably fittable within respective curved slots 304 within the rigid headband assembly 104. Screws or other fasteners with heads greater in diameter than the posts 302 can be rotatably inserted into the posts to prevent separation of the headband assembly 104 from the HMD body 102.

[0023] The HMD body 102 and the headband assembly 104 may be more generally referred to as members of the HMD, and, therefore, may be referred to as a first member and a second member, respectively, where the use of “first,” “second,” and so on, is merely used to clarify a particular element being reference and is not limiting as to the number or the order of the elements.

For example, the mechanical mount feature 200 can rotatably attach the first member and the second member to one another. The mount feature 200 may therefore be used in contexts other an HMD device 100 as depicted in FIGs. 3A-3E.

[0024] FIGs. 3A-3E are described in example reference to the lower post 302 within the lower curved slot 304, but the description pertains equally to the upper post within the upper curved slot. FIG. 3A shows the mechanical mount feature 200 when the headband assembly 104 is rotated fully behind the HMD body 102 as in FIG. 1A. The curved slot 304 has a curved interior sidewall 306 that is attached, or fixed, to the headband assembly 104 at the end at which the post 302 is positioned within the slot 304 when the headband assembly 104 has been rotated fully behind the HMD body 102 in FIG. 1A. The sidewall 306 is not attached to, and thus unfixed at, the other end of the curved slot 304 in the example of FIG. 1A. [0025] A portion 308 of the curved interior sidewall 306 corresponds to an adjustability zone of the curved slot 304 in which the sidewall 306 is curved in correspondence with the movement arc of the post 302 within the slot 304. The portion 308 of the curved interior sidewall 306 does not interfere with the post 302 as the post 302 moves among positions adjacent to the portion 308. There is minimal friction between the sidewall 306 and the post 302 within the adjustability zone.

[0026] The headband assembly 104 can likewise rotate relative to the HMD body 102, with minimal resistance (e.g., freely), within a range of positions as the post 302 moves through the adjustability zone. In another implementation, the headband assembly 104 and the HMD body 102 can rotate relative to one another within a range of positions in correspondence with detents, as the post 302 moves through the adjustability zone from detent to detent. The range of positions can extend from the position at which the headband assembly 104 is fully behind the HMD body 102, as in FIG. 1A, to a position at which the headband assembly 104 is rotated clockwise at a given angle relative to its position in FIG. 1A. Within this range of positions, the headbands 110 and 112 of FIG. 1A can be secured to the user’s head in correspondence to a usage mode in which the HMD device 100 is worn and used by the user in a hands- free manner.

[0027] Having a range of positions corresponding to the hands-free usage mode in which the post 302 is freely movable through the adjustability zone improves adjustability of the HMD device 100 when worn by a user in this usage mode. This is why the zone corresponding to the portion 308 of the inner sidewall 306 of the curved slot 304 is referred to as an adjustability zone. That is, the zone corresponding to the portion 308 of the interior sidewall 306 can be considered an adjustability zone in that the HMD 100 can be worn by a user within a range of positions when the post 302 is within this zone of the curved slot 304. For example, a user may find it most comfortable to have the headband assembly 104 rotated slightly clockwise from the position of FIG. 1A.

[0028] FIG. 3B shows the mechanical mounting feature 200 as the rigid headband assembly 104 is rotated clockwise relative to the HMD body 102 as compared to FIG. 3A, per arrow 301. In FIG. 3B, the post 302 is incident to the curved interior sidewall 306 of the curved slot 304 at the end of the portion 308 corresponding to the adjustability zone, opposite the end at which the post 302 is incident in FIG. 1 A. FIGs. 3A and 3B therefore show the bounds of the range of positions of the headband assembly 104 relative to the HMD body 102 that correspond to the hands-free usage mode of the HMD device 100.

[0029] FIG. 3C shows the mechanical mount feature 200 as the headband assembly 104 is further rotated clockwise relative to the HMD body 102 as compared to FIG. 3B, per arrow 301. A portion 312 of the curved interior sidewall 306 corresponds to an interference zone of the curved slot 304 adjacent to the adjustability zone. The portion 312 of the interior sidewall 306 interferes with the post 302 as the post 302 moves adjacent to the portion 308 and thus through the interference zone. (Stated another way, the curved slot 304 can be considered as moving about the post 302, such that the headband assembly 104 moves relative to the HMD body 102.) There is more friction between the post 302 and the sidewall 306 as the post 302 moves through the interference zone than when the post 302 moves through the adjustability zone.

[0030] The interference between the curved interior sidewall 306 and the post 302 can result from non-elastic and/or elastic deformation of the interior sidewall 306. The sidewall 306 may non-elastically deform in that the post 302 may movably extend the sidewall 306 inwards, as indicated by arrow 313, as the post 302 moves through the interference zone. The interior sidewall 306 may additionally or instead elastically deform via the post 302 slightly compressing the sidewall 306 as the post 302 moves through the interference zone. In an implementation in which the sidewall 306 is attached at both ends of the curved slot 304 and not just at one end, the sidewall 306 may elastically deform without non-elastically deforming.

[0031] The headband assembly 104 is rotatable relative to the HMD body 102 as the post 302 moves through the interference zone, but not as freely as when the post 302 moves through the adjustability zone. The headband assembly 104, in other words, is rotatable relative to the HMD body 102 with more resistance as the post 302 moves through the interference zone as compared to when the post 302 moves through the adjustability zone. The post 302 is thus interferingly movable through the interference zone, which is why the zone is referred to as such. That is, the zone corresponding to the portion 312 of the interior sidewall 306 can be considered an interference zone in that the HMD body 102 and the headband assembly 104 are rotatable relative to one another as the post 302 moves through this zone of the curved slot 304 with greater resistance than when the post 302 moves through the adjustability zone. The friction between the post 302 and the sidewall 306 may increase as the post 302 moves through the interference zone. [0032] FIG. 3D shows the mechanical mount feature 200 as the headband assembly 104 is further rotated clockwise relative to the HMD body 102 as compared to FIG. 3C, per arrow 301. In FIG. 3D, the post 302 is incident to the curved interior sidewall 306 of the curved slot 308 at the end of the portion 312 corresponding to the interference zone at which friction between the post 302 and the sidewall 306 may be at a maximum. For example, the sidewall 306 may flare in shape towards the post 302 at this position to maximally interfere with the post 302, causing the post 302 to maximally non-elastically deform the sidewall 306 inwards, per arrow 313.

[0033] The sidewall 306 can be said to maximally interfere with the post 302 at the position in which the sidewall 306 maximally extends into the curved slot 308. Therefore, maximum force has to be exerted to move the post 302 past the sidewall 306 in this position. The sidewall 306 is maximally non-elastically deformed inwards at this position in that the sidewall 306 is pushed inward by the post 302, per arrow 313, at this position. [0034] FIG. 3E shows the mechanical mount feature 200 as the headband assembly 104 is further rotated clockwise relative to the HMD body 102 as compared to FIG. 3D, per arrow 301 , until the headband assembly 104 is rotated fully above the HMD body 102 as in FIG. 1B. A portion 314 of the curved interior sidewall 306 corresponds to a detent area of the curved slot 306 adjacent to the interference zone. The interference zone of FIGs. 3C and 3D is between the adjustability zone of FIGs. 3A and 3B and the detent area of FIG. 3E. The headband assembly 104 is rotated clockwise fully above the FIMD body 102 at ninety degrees when the post 302 is in the detent area in FIG. 3E.

[0035] When the post 302 enters the detent area in FIG. 3E from the interference zone in FIG. 3D, the interior sidewall 306 no longer maximally interferes with the post 302. Stated another way, the post 302 no longer maximally deforms the interior sidewall 306, including no longer forcing the sidewall 306 maximally inwards. Movement of the post 302 from the interference zone of FIG. 3D to the detent area of FIG. 3E thus releases tension in the interior sidewall 306 caused by deformation of the sidewall 306. The sidewall 306 therefore snaps back into the same position at which it started in FIG. 3A, per arrow 315. [0036] The sidewall 306 can have a curvature at the portion 314 matching the curvature of the post 302, releasably locking the post 302 at the detent area of the curved slot 304 and correspondingly releasably locking the headband assembly 104 above the FIMD body 102 as in FIG. 1 B. Snapping back of the interior sidewall 306 when the post 302 enters the detent area in FIG. 3E can result in an audible click when the post 302 contacts the sidewall 306 at the portion 314. This audible click can serve as audible feedback that the headband assembly 104 has releasably locked above the FIMD body 102. [0037] The detent area of the curved slot 304 is referred to as such because the post 302 is releasably locked at the detent area. That is, the area of the curved slot 304 incident to the portion 314 of the interior sidewall 306 can be considered a detent area in that the post 302 is releasably locked against the portion 314 at this area. The corresponding releasably locked position of headband assembly 104 fully above the HMD body 102 in FIG. 3E prevents the headbands 110 and 112 of the headband assembly 104 from being secured to the user’s head, as in FIG. 1B. This releasably locked position thus corresponds to a usage mode in which the HMD device 100 is not worn by the user but can still be used by the user manually maintaining the HMD body 102 against his or her face, without interference from the headband assembly 104. Without the detent area to releasably lock the post 302 within the curved slot 304, the weight of the headband assembly 104 and/or the weight of any cables attached to the HMD device 100 may result in the headband assembly 104 inadvertently rotating back downwards, counter-clockwise, from the position of FIG. 3E.

[0038] The headband assembly 104 can be rotated from the position fully above the HMD body 102 in FIG. 3E through the interference zone per FIGs. 3D and 3C and then through the adjustability zone per FIG. 3B, to the position fully behind the HMD body 102 in FIG. 3A. The post 302 has to initially overcome the maximal resistance provided by the flare at the end of the interference zone in FIG. 3D to enter this zone from the detent area of FIG. 3E. (Stated another way, the curved slot 304 can be considered as moving about the post 302, such that the headband assembly 104 moves relative to the HMD body 102.) Resistance decreases as the post 302 moves back through the interference zone from FIG. 3D to FIG. 3C, before reaching minimal resistance as the post 302 enters the adjustability zone in FIG. 3B and finally is rotated to the end of the adjustability zone per FIG. 3A. [0039] The mechanical mount feature 200 in the example of FIGs. 3A-3E permits the headband assembly 104 to be rotated relative to the FIMD body 102 ninety degrees clockwise from the behind the FIMD body 102 to above the FIMD body 102, and ninety degrees counter-clockwise from above the FIMD body 102 to behind the FIMD body 102. In another implementation, the mechanical mount feature 200 may have a configuration that is the mirror opposite to that in the example of FIGs. 3A-3E. In such an implementation, the headband assembly 104 can be rotated ninety degrees counter-clockwise from behind the FIMD body 102 to below the FIMD body 102, and ninety degrees clockwise from below the HMD body 102 to behind the HMD body 102. [0040] FIGs. 4A and 4B show side views of the example HMD device 100 in when the headband assembly 104 can be so rotated below the HMD body 102, either in addition to or in lieu of above the HMD body 102. As in FIGs. 1 A and 1 B, the HMD body 102 includes a face gasket 106 and an end 108 at which a display can be internally mounted within the HMD body 102. Similarly, the headband assembly 104 can include back and top headbands 110 and 112, and can also include an earpiece 114 having a speaker, for either or both ears of the user. [0041] In FIG. 4A, the headband assembly 104 has been rotated counter clockwise from a position behind the HMD body 102 as in FIG. 1A to a position below the HMD body 102, preventing the headbands 110 and 112 from being secured to the user’s head. However, the headband assembly 104 has not been rotated ninety degrees fully below the HMD body 102 in FIG. 4A, but rather has been rotated less than ninety degrees below the HMD body 102. In the position of FIG. 4A, the HMD device 100 is not worn by the user, but rather the headband assembly 104 acts as stand (or rest on an external stand in another example), permitting the device 100 to vertically rest on a horizontal surface 402 with the HMD body 102 suspended above the headband assembly 104.

[0042] For example, In the position of FIG. 4A, the HMD body 102 can be considered as being suspended above the headband assembly 104 in that the HMD body 102 is positioned above the headband assembly 104 such that the HMD device 100 can vertically rest on the horizontal surface 402 without falling or toppling over. More generally, the HMD body 102 can be considered as being suspended above headband assembly 104 in that the HMD body 102 is positioned above the headband assembly 104 without the weight of the HMD body 102 causing the HMD body 102 and the headband assembly 104 to rotate relative to one another.

[0043] The usage mode of FIG. 4A can correspond to the mechanical mount feature 200 per FIG. 3D, but where the feature 200 has a mirror opposite configuration. Specifically, the position at which the headband assembly 104 is rotated below the HMD body 102 in FIG. 4A can correspond to the position of the post 302 at the end of the interference zone of the curved slot 304 in the mirror opposite configuration to that of FIG. 3D. Because friction between the post 302 and the curved interior sidewall 306 is at a maximum in the interference zone at this position, the headband assembly 104 can stably remain in the position of FIG. 4A in which the HMD device 100 rests on the surface 402 with the HMD body 102 suspended above the headband assembly 104. [0044] In FIG. 4B, the headband assembly 104 has been rotated ninety degrees counter-clockwise to a position fully below the HMD body 102, also preventing the headbands 110 and 112 from being secured to the user’s head. This position similarly corresponds to a usage mode in which the user does not wear the HMD device 100. The headband 112 may be removably fastened at the HMD body 102, so that it can be unfastened in the position of FIG. 4B. The usage mode of FIG. 4B can correspond to the mechanical mount feature 200 per FIG. 3E, but where the feature 200 has a mirror opposite configuration. Specifically, the position at which the headband assembly 104 is rotated fully below the body 100 in FIG. 4B can correspond to the position of the post 302 at the detent area of the curved slot 304 in the mirror opposite configuration to that of FIG. 3D.

[0045] The mechanical mount feature 200 thus permits the headband assembly 104 to be rotated relative to the HMD body 102 ninety degrees clockwise from behind the HMD body 102 to above the HMD body 102, or ninety degrees counter-clockwise from behind the HMD body 102 to below the HMD body 102. Whether the headband assembly 104 can be rotated clockwise or counter-clockwise from behind the HMD body 102 depends on whether the mechanical mount feature 200 has the configuration of FIGs. 3A-3E or the mirror opposite configuration. In other implementations, however, the headband assembly 104 may be rotatable both clockwise and counter-clockwise from behind the HMD body 102.

[0046] For instance, in such an implementation there may be one post 302 movably fittable within one corresponding curved slot 304. The position of the post 302 within the middle of the slot 304 may correspond to the position of the headband assembly 104 rotated behind the HMD body 102, as in FIG. 1A. The position of the post 302 at the bottom end of slot 304 may correspond to the position of the headband assembly 104 rotated fully above the HMD body 102, as in FIG. 1 B. The position of the post 302 at the top end of the slot 304 may correspond to the position of the headband assembly 104 rotated fully below the HMD body 102, as in FIG. 4B. The sidewall 306 may be fixed at the center of the slot 304 and unfixed at both ends of the slot 304.

[0047] FIG. 5 shows a block diagram of an example HMD device 100. The HMD device 100 includes an HMD body 102 positionable against the face of a user opposite the user’s eyes. The HMD device 100 includes a headband assembly 104 that can include a headband securable to the head of the user.

The HMD device 100 includes a mechanical mount feature 200 that rotatably attaches the headband assembly 104 to the HMD body 102. The headband assembly 104 is rotatable relative to the HMD body 102 among different positions corresponding to multiple usage modes of the HMD device 100.

[0048] FIG. 6 shows block diagram of an example mechanical mount feature 200 for rotatably attaching a first member and a second member. The mechanical mount feature includes a post 302 on the first member, and a curved slot 304 within the second member and within which the post 302 is movably fittable. The slot 304 includes an adjustability zone 602 within which the post 302 is freely movable. The slot 304 includes an interference zone adjacent 604 to the adjustability zone 602 and through which the post 302 is interferingly movable at higher resistance than within the adjustability zone 602. The slot 304 includes a detent area 606 adjacent to the interference zone 604 at which the post 302 is releasably locked in position.

[0049] FIG. 7 shows an example method 700 for using an HMD device. The method 700 includes rotating a headband assembly of the HMD device behind an HMD body of the HMD device (702), permitting usage of the HMD device in a hands-free manner in which the user wears the HMD device. The method 700 further includes rotating the headband assembly upwards above or downwards below the HMD body (704), permitting usage of the HMD device while the HMD body is manually maintained against a face of the user without interference from the assembly.

[0050] Techniques have been described herein by which a headband assembly of an HMD device can be rotatably attached to an HMD body of the HMD device. The assembly can thus be rotated relative to the body among different positions corresponding to multiple usage modes of the HMD device. A mechanical mount feature may rotatably attach the headband assembly to the HMD body, and can include a curved slot within the assembly and a post on the body that is movably fittable within the slot.