Tracing sensation display device, virtual space display device

Abstract

Allows for modification of roughness and texture. [Solution] A tracing sensation presentation device that presents a tracing sensation to the wearer's finger, comprising a rotating disc having a contact surface that contacts and stimulates the finger, a rotation drive unit that rotates the rotating disc, and a position regulating unit that restricts the position of the finger to a position where it can contact the rotating disc, wherein the contact surface is capable of periodically changing the stimulation to the contacting finger.

Description

Technical Field

[0001] The present invention relates to a tracing sensation presentation device and a virtual space display device.

Background Art

[0002] We perform tracing movements in our daily lives, and perceive the texture and friction of an object using the sensations that occur during such movements, that is, the tracing sensation. Presenting the tracing sensation plays an important role in improving the quality of the virtual reality experience.

[0003] Many methods for presenting the tracing sensation by reproducing skin deformation during tracing movements have been proposed so far. These are mainly classified into those that change the coefficient of friction, those that move the contact surface in the shear direction, and those that use the rotation of rollers, disks, or belts. Among them, the method using a belt or the like can faithfully reproduce the skin deformation during actual tracing movements, and is considered to be able to present a highly realistic tracing sensation (Patent Document 1).

[0004] However, such conventional techniques as described above have a common problem that the device becomes large-sized, or the device configuration tends to become complicated.

[0005] To solve this problem, the inventor of the present invention proposed a method for presenting the tracing sensation by bringing a fingertip into contact with the center of a rotating disk (Non-Patent Document 1).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Non-Patent Documents

[0007]

Non-Patent Document 1

[0008] The technology described in Non-Patent Document 1 above had the advantage of being able to significantly miniaturize the device. On the other hand, it had the problem that the range of applicable applications was limited because it could not dynamically change the texture presented. In other words, the technology described in Non-Patent Document 1 above had the problem that it could present a specific tracing sensation, but could not present different tracing sensations.

[0009] This invention has been made in view of the above circumstances and aims to achieve the following objectives. 1. To realize a device that provides a tracing sensation that can modulate the perceived roughness and texture. 2. To realize a tracing sensation presentation device that can present different tracing sensations. 3. Allow for dynamic switching of the perceived roughness level. 4. Increase the range of traceable textures that can be presented. [Means for solving the problem]

[0010] When a person traces the surface of an object, vibrations are generated in the fingertips due to the interaction between the object's surface and the fingertips. The frequency of these vibrations depends on the surface shape of the object; for example, it is higher when the surface is finely textured and lower when it is rough. Therefore, by changing the frequency of the vibrations presented during tracing, it is possible to modulate the perceived roughness and texture.

[0011] The inventors, through diligent research, have discovered that the perception of roughness during tracing motion can be dynamically modulated by devising the surface shape of a rotating disk. By creating irregularities on the surface of the disk, it is thought that the frequency of vibrations generated in the fingertip skin can be changed by changing the rotation speed, and this may allow for the modulation of the perceived roughness. On the other hand, there is prior research that states that texture perception does not depend on tracing speed. In response to this, the inventors have completed the present invention, which enables texture modulation by dealing with a low-frequency range that humans can perceive as a change in speed.

[0012] (1) A tracing sensation presentation device according to one aspect of the present invention is A rotating disc having a contact surface that stimulates the finger, A rotation drive unit that rotates the aforementioned rotating disk, It has, The aforementioned contact surface is capable of varying the stimulation to the finger. This resolved the above issues. (2) The tracing sensation presentation device of the present invention, in the above (1), The aforementioned contact surface allows for spatially periodic changes in the stimulation to the finger. It is possible. (3) The tracing sensation presentation device of the present invention, in the above (2), The contact surface is capable of varying the stimulation in a direction along the contact surface. It is possible. (4) The tracing sensation presentation device of the present invention, in the above (3), The contact surface has contact portions formed at a predetermined distance apart in the rotational direction of the rotating disk. It is possible. (5) The tracing sensation presentation device of the present invention, in the above (4), The contact portion is a convex or concave portion extending in a direction intersecting the rotational direction of the rotating disk. It is possible. (6) The tracing sensation presentation device of the present invention, in the above (5), The contact portion has different inclines for the step formed in front of the rotating disk in the direction of rotation and for the step formed behind the rotating disk in the direction of rotation. It is possible. (7) In the tracing sensation presentation device of the present invention, in the above (1), the contact surface can change the stimulus to the finger in a time cycle. It is possible. (8) In the tracing sensation presentation device of the present invention, in the above (7), the contact surface can change the stimulus in the direction along the normal line of the contact surface. It is possible. (9) In the tracing sensation presentation device of the present invention, in the above (8), a power source for applying a voltage for adsorbing a finger to the contact surface by an electric charge as a predetermined frequency is connected to the rotating disk. It is possible. (10) In the tracing sensation presentation device of the present invention, in the above (9), the frequency of the voltage applied to the rotating disk is higher than the rotation speed of the rotating disk. It is possible. (11) The virtual space display device of the present invention includes the tracing sensation presentation device according to any one of the above (1) to (9), a detection unit that detects movement information of a user or a character in a virtual space, and a control unit that controls the tracing sensation presentation device based on the movement information detected by the detection unit. It has It is possible.

[0013] In the configuration described in (1) above, the stimulation from the contact surface to the finger changes periodically, and the contact surface located on the surface of the rotating disk and in contact with the finger rotates relative to the finger in accordance with the rotation of the rotating disk, thereby dynamically modulating the perception of roughness during tracing. The stimulation from the contact surface to the finger is caused by the unevenness on the contact surface changing its contact position with the finger in accordance with the rotation, or by the periodically changing charge on the contact surface changing the frequency of the vibration stimulation generated on the fingertip skin due to the change in rotation speed. The perceived roughness can be modulated by these periodic stimuli. Therefore, a tracing sensation presentation device that can modulate the roughness and texture perceived at the fingertip can be realized.

[0014] In this state, the rotation drive unit rotates the rotating disk at a predetermined speed. The rotation drive unit can modulate the rotation speed of the rotating disk. Furthermore, the position regulating unit can fix the relative position between the finger and the rotating disk so that the contact position of the fingertip does not change even when the rotating disk rotates. The position regulating unit can restrict the contact position of the fingertip so that it does not deviate from the center of rotation of the rotating disk.

[0015] In the configuration described in (2) above, multiple contact points are formed on the contact surface that contacts the fingertip, spaced apart in the rotational direction. If the distance between the contact points in the rotational direction is greater than the two-point discrimination threshold, the contact points come into contact with the fingertip, and a stimulus is delivered from the contact points to the fingertip. This stimulus to the fingertip is transmitted to the brain.

[0016] The brain has velocity detectors that detect the speed at which stimuli are moving. These velocity detectors recognize a stimulus pattern at a given moment from the activity of receptors on the skin, and at the next moment, they understand that this stimulus pattern has shifted. The velocity detectors recognize the amount of pattern shift. From this amount of pattern shift and the magnitude of the recognition time, the velocity detectors calculate how fast the stimulus is moving. In this way, the brain detects the speed at which the stimulus is moving. This is well known in visual velocity detection, but in this invention, we anticipate that a similar mechanism exists in tactile perception and utilize it.

[0017] Here, by changing the rotation speed of the contact area through the rotation of the rotating disk, the stimulus to the contacting fingertip changes in a spatial periodic manner. This periodic change in stimulus causes the stimulus movement speed (pattern movement speed) to be perceived as roughness. Therefore, by modulating the rotation speed of the rotating disk, the modulated roughness can be perceived by the fingertip. It is thought that when the rotation is fast, the stimulus is perceived as stronger or faster, and thus feels rougher. Here, it is preferable that the distance between contact points in the rotational direction be set to be greater than the two-point discrimination threshold. The two-point discrimination threshold at the fingertip is approximately 2-3 mm, and the distance (gap) between contact points in the rotational direction can be, for example, 2 mm or more.

[0018] In the configuration described in (3) above, for example, multiple contact points spaced apart in the rotational direction are formed on the contact surface, and the spacing between the contact points in the rotational direction is set to be greater than the two-point discrimination threshold. When multiple spaced-apart contact points come into contact with a fingertip, each contact point stimulates the fingertip, and this is recognized by the fingertip as a pattern along the contact surface. As the contact points rotate along the contact surface due to the rotation of the rotating disk, the stimulation recognized by the fingertip as a pattern moves along the contact surface. The movement of the stimulation can present a sense of roughness. Here, by modulating the rotation of the rotating disk, the rotational speed of the contact points can be changed, and the stimulation to the fingertip can be changed in the direction along the contact surface. By changing the stimulation, the modulated sense of roughness can be perceived by the fingertip. It is thought that when the rotation is slow, the stimulation is perceived as weaker or slower, resulting in a smoother feeling.

[0019] In the configuration described in (4) above, the contact surface has convex or concave portions that are spaced apart by a predetermined distance in the rotational direction of the contact surface, which serve as contact portions that stimulate the fingertip. With this structure, the contact portions come into contact with the fingertip at multiple positions spaced apart in the rotational direction. At the contact positions of the contact portions, the fingertip is stimulated. This stimulation forms a pattern with a planar distribution along the contact surface. This stimulation is applied to the fingertip as a pattern, allowing the fingertip to recognize it.

[0020] Furthermore, as the contact area rotates due to the rotation of the rotating disc, the position of the stimulus on the fingertip changes periodically and moves in a direction along the contact surface. Simultaneously, the stimulus on the fingertip moves while maintaining its pattern. This moving pattern stimulus makes it possible to present a predetermined tracing sensation to the fingertip. Moreover, by modulating the rotation of the rotating disc, it is possible to perceive a modulated roughness sensation with the fingertip. By having contact points formed at a predetermined distance apart in the direction of rotation on the contact surface, you can feel with your fingertips that the perceived roughness of the texture changes distinctly depending on the movement speed (rotation speed) of the contact points.

[0021] Here, if the contact area on the rotating disk is formed as a sufficiently fine recess or protrusion, the fingertip can only perceive that it is of a predetermined roughness, regardless of the speed. Therefore, if there is no contact area on the rotating disk, the perceived roughness does not change even if the rotation speed is changed. In contrast, the present invention provides a contact surface with contact portions formed with a separation distance set to be greater than the two-point discrimination threshold, thereby enabling the perception of modulated roughness with the fingertips and allowing for the presentation of a wide range of roughness sensations. By forming the contact portions as convex or concave portions, it becomes easy to realize a configuration in which multiple contact portions having a sufficient separation distance along the rotational direction are arranged along the contact surface. The top of the contact area can be formed at the same height as the contact surface. Multiple contact areas can all be formed at the same height.

[0022] Here, if a convex portion is formed as the contact area, the step formed by the corner at the top of the convex portion, which becomes the edge, makes contact with the skin of the fingertip in a way that indents it. When the contact surface rotates, the step first hits the skin in front of the convex portion in the direction of rotation. At the same time, the contact position of this step that first hit the skin moves in the direction of rotation. In other words, the corner of the convex portion that first hits and pushes into the skin in the direction of rotation moves continuously across the surface of the skin while moving in the direction of rotation. This continuous contact of the corner provides stimulation to the fingertip. The rotation of the connecting surface continues the stimulation to the fingertip. The rotation of the connecting surface continues the moving stimulation.

[0023] Here, if a recess is formed as the contact area, the step formed at the corner that becomes the opening edge of the recess comes into contact with the skin of the fingertip in such a way that the contact surface indents it. When the contact surface rotates, the step strikes the skin of the fingertip that was not in contact with the contact surface within the recess at the rear of the recess in the direction of rotation. In other words, the corner of the recess that strikes and pushes the skin at the rear in the direction of rotation moves continuously across the surface of the skin as it moves in the direction of rotation. This continuous contact of the corner stimulates the fingertip. The rotation of the connecting surface continues the stimulation to the fingertip. The rotation of the connecting surface continues the moving stimulation.

[0024] Alternatively, if a recess is formed as the contact area, the skin of the fingertip that was being pressed will separate from the contact surface at the step formed at the corner that forms the opening edge of the recess. As the contact surface rotates, the corner of the recess from which the skin first separates moves forward in the direction of rotation, and as it moves in the direction of rotation, it continuously moves across the surface of the skin. This creates a situation where the pressure on the skin by the corner of the recess is continuously released, providing stimulation to the fingertip. The moving stimulation continues as the connecting surface rotates. The movement of these corners allows for a tactile sensation to be provided to the fingertips.

[0025] Therefore, if the shape, size, and arrangement along the contact surface are the same, the convex and concave parts can achieve the same effect. Furthermore, multiple contact points only need to be positioned on the contact surface with the necessary spacing between them in the direction of rotation. For this reason, the contact points can be protrusions or recesses formed in the radial direction of the rotating disk. In other words, as long as the spacing in the direction of rotation is sufficient, the contact points are not limited to ridges or slits (grooves).

[0026] The contact area can be a continuous ridge or slit, or an intermittent ridge or slit. Furthermore, it can be a point-like protrusion or hole formed at intervals in the radial direction of the rotating disc. In this case, it is necessary to maintain a sufficient separation distance in the rotational direction.

[0027] Furthermore, the dimensions of the contact area in the rotational direction are not particularly limited as long as it can provide a tactile sensation to the fingertip. The same effect can be obtained whether the contact area is convex or concave, and even if it is extremely thin. This is because, regardless of the width, the skin can be deformed by the movement of the corners of the step, resulting in a similar effect. Furthermore, the depth or height of the contact area is not particularly limited, as long as a step is formed that allows the presence of the corner to be detected and stimulated when it comes into contact with the skin of the fingertip, and the corner can be recognized. The depth or height of the contact area can be 0.5 mm or more, or 1 mm or more.

[0028] In the configuration of (5) above, the contact portion can be formed as a convex portion as a ridge extending in a direction intersecting the rotational direction of the contact surface, or as a concave portion as a slit (groove) extending in a direction intersecting the rotational direction of the contact surface. This makes it possible to apply stimulation to the fingertip by the rotation of the rotating disc while maintaining a sufficient separation distance in the rotational direction. Here, extending in a direction intersecting the rotational direction of the contact surface includes extending along the radial direction. Extending in a direction intersecting the rotational direction of the contact surface is not limited to the radial direction passing through the center of rotation of the rotating disk. Extending in a direction intersecting the rotational direction of the contact surface means that it is formed along a line connecting a position close to the center of rotation of the rotating disk to its outer circumference. For example, multiple protrusions formed by parallel straight lines equidistant from the center of rotation can be used as convex portions. The tops of the convex portions can be formed at the same height as the contact surface. Multiple convex portions can all be formed at the same height.

[0029] Here, height refers to the position in the direction normal to the contact surface. Similar to the convex portion, multiple slits arranged parallel to each other at an equal distance from the center of rotation can be used to form recesses. All of these recesses can be formed so that they are recessed from the same contact surface. Furthermore, the contact portion may have protrusions or slits formed continuously in the radial direction, or it may have protrusions or slits formed intermittently in the radial direction. For example, a convex portion can be formed by arranging point-like convex shapes in the radial direction. Alternatively, a concave portion can be formed by arranging point-like holes in the radial direction on a flush contact surface. In these cases, the diameter dimension at the point-like contact area can correspond to the width dimension of the protrusion or slit. The width dimension of the protrusion or slit is the dimension in the rotational direction of the contact surface.

[0030] In the configuration of (6) described above, the contact portion may have different inclinations in both the forward and reverse rotation directions of the rotating disk, depending on the direction of rotation. For example, if a protrusion is formed as a contact area, the slope of the side surface descending from the top of the step differs between the forward and backward positions in the rotational direction. The slope of the side surface in the forward position in the rotational direction can be greater or smaller than the slope of the side surface in the backward position. Alternatively, multiple protrusions may all have equal inclination on the sides facing the same direction of rotation. In all recesses, the inclination on the side facing forward can be greater or less than the inclination on the side facing backward.

[0031] Multiple protrusions all have equal lateral slopes when positioned in the same orientation in the direction of rotation. Multiple protrusions can also have equal lateral slopes when facing forward. Alternatively, if a recess is formed as a contact area, the inclination of the side surface that descends from the opening of the contact surface to the bottom due to the step at the edge of this recess differs between the forward and backward positions in the direction of rotation. Multiple recesses all have equal inclination of the side surfaces in the same direction of rotation. Alternatively, multiple recesses all have equal magnitude of inclination on the side surfaces in the same direction of rotation.

[0032] Due to these structures, when the rotating disc rotates in one of the forward or reverse rotation directions, the stimulation from the contact points spaced apart in that direction to the fingertips is of the same intensity and type. Similarly, when the contact surface rotates in the other of the forward or reverse rotation directions, the stimulation from the contact points spaced apart in that direction to the fingertips is of the same intensity and type. At the same time, different stimuli are transmitted from the contact points to the fingertips depending on the direction of rotation of the rotating disc.

[0033] In this case, if the steep, inclined step is facing forward in the direction of rotation, the step will constantly bump against the skin of the fingertips, resulting in a stronger stimulus compared to reverse rotation.

[0034] On the other hand, when a gentle step with a small incline rotates so that it faces forward in the direction of rotation, the side of the step approaches the fingertip smoothly, avoiding a sudden impact with the skin. Therefore, it does not cause strong stimulation and provides a relatively weaker stimulus compared to rotation in the opposite direction. In other words, when a step with a steep incline rotates so that it faces forward in the direction of rotation, it can present a rougher sensation compared to when a step with a gentle incline rotates so that it faces forward in the direction of rotation. When a step with a gentle incline rotates so that it faces forward in the direction of rotation, it can present a smoother sensation compared to when a step with a steep incline rotates so that it faces forward in the direction of rotation. This allows different stimuli to be applied from the contact point to the fingertip depending on the forward and reverse rotation direction of the contact surface. Therefore, it is possible to switch between roughness and texture simply by changing the direction of rotation.

[0035] Furthermore, by changing the rotation speed in addition to the forward and reverse rotation direction, it is possible to change the feel of the tracing surface in accordance with the change in rotation. Here, a steep step can be a side surface that descends from the top at a near-right angle in the direction normal to the contact surface. The angle between the contact surface and the side surface in a cross-section along the direction of rotation can be near a right angle. A step with a gentle slope can have a side surface that slopes gently downward from the top in a direction close to the direction along the contact surface. The angle between the contact surface and the side surface in a cross-section along the direction of rotation can be obtuse.

[0036] Furthermore, if the contact area is formed by multiple radially extending protrusions with different inclines depending on the direction of rotation, it will take on a so-called sawtooth shape. Furthermore, even when a recess is formed as a contact area, by forming side surfaces with different inclines depending on the front-to-back position in the rotational direction, it becomes possible to switch the roughness and texture depending on the rotational direction, similar to the convex portion described above.

[0037] In the configuration described in (7) above, a stimulus is generated on the contact surface, for example, a stimulus that causes the fingertip to adhere. At this time, the contact surface generates the fingertip adhesion stimulus with dynamic changes so that its intensity changes over time. This adhesion stimulus changes periodically at a predetermined frequency. As the adhesion stimulus changes at the predetermined frequency on the contact surface, the fingertip repeatedly switches between a state of adhesion and a state of non-adhesion. As a result, the fingertip receives the change in stimulus at that frequency. The adhesion stimulus is given to the fingertip as a vibration at that frequency on the contact surface. If only an adhesive force is generated on the contact surface, the fingertip usually cannot feel this adhesive force.

[0038] In addition to this state, when the rotating disc is rotated, the fingertip and the rotating disc move relative to each other. As it rotates, the contact surface in the suction state and the skin of the fingertip move relative to each other. As the skin repeatedly adheres to and separates from the contact surface, the contact surface rotates, causing the skin to periodically alternate between being dragged and not being dragged. Because the adhesive force is related to the frictional force, this periodic movement of the adhesive force on the fingertip changes the frictional force on the finger, resulting in a dragging force acting on the fingertip.

[0039] If only an adhesive force is generated, it cannot be felt as a tactile sensation with the fingertips. However, by also rotating the rotating disc, it is possible to present a tactile sensation, such as a rough texture, to the fingertips. Therefore, by changing the rotation speed while an attractive force is generated between the rotating disc and the finger, the frictional sensation at the contact surface can be modulated. For example, it is preferable that the frequency at which the adsorption stimulus changes is large relative to the rotation speed of the rotating disk. It is also preferable that the adsorption stimulus at the contact surface is homogeneous within the surface and simultaneously undergoes periodic changes.

[0040] In the configuration described in (8) above, the stimulus delivered to the finger from the contact surface is oriented along the normal to the contact surface. By combining the temporal change in the direction of this stimulus with the rotation of the contact surface providing the stimulus, it becomes possible to transmit a sense of friction from the contact surface to the fingertip. This makes it possible to modulate the sense of roughness perceived by the fingertip by modulating the rotation of the rotating disc. It is thought that when the rotation is slow, the stimulus is perceived as weaker or slower, resulting in a smoother feeling.

[0041] In the configuration described in (9) above, a voltage is applied to the rotating disk to accumulate charge on the contact surface, thereby exerting an attractive force on the fingertip in the direction normal to the contact surface. Specifically, an insulating film is formed on the surface of the rotating disk, which is a conductor, and a high voltage is applied to the rotating disk. More precisely, when a potential difference is formed between the rotating disk and the finger, charge accumulates near the contact surface. When charge accumulates on the contact surface, an attractive force is generated between them, resulting in the phenomenon of the skin and the contact surface being attracted to each other. This attraction phenomenon itself has been known for a long time.

[0042] While mere suction force is not yet perceptible as a tactile sensation, if the fingertip and the contact surface are moved relative to each other in this state, the frictional force between the fingertip and the contact surface changes due to the suction force, and a dragging force acts on the fingertip. This changes the sensation of friction at the contact surface. Here again, it is only when the contact surface rotates that a sensation such as roughness can be presented to the fingertip. The voltage applied to the rotating disc is dynamically changed. For example, it can be changed up and down within a range of approximately 0V to 300V, switching at approximately 50Hz. This causes the disc to repeatedly switch between being attracted and not attracted at a 50Hz cycle, and the change in frictional force is felt at the fingertips at 50Hz, thus perceived as a 50Hz vibration.

[0043] The charge on the rotating disk, when a voltage is applied, is uniform across the entire contact surface. In this state, as the rotating disk rotates, if the voltage changes over time at 50Hz, the fingertip can perceive this as a vibration as if it were in contact. In other words, when a voltage change of 50Hz is applied, the attractive force to the fingertip itself changes at 50Hz. However, this attractive force itself is usually not felt. Therefore, while an attractive force is applied to the fingertip, the rotating disk is rotated to move the relative skin of the fingertip and the rotating disk.

[0044] The adhesive force is related to frictional force. When the skin repeatedly sticks to and detaches from the rotating disc, the rotating disc rotates, causing the skin of the fingertips to alternate between being dragged and not dragged at 50Hz. This change in frictional force is perceived by the fingertips as a sense of roughness or texture.

[0045] In the configuration described in (10) above, by having a frequency of the applied voltage greater than the rotation speed of the rotating disk, changes in frictional force between the fingertip and the contact surface can be presented to the fingertip as a sense of roughness or texture. By changing the rotation speed of the rotating disk, a modulated tracing sensation can be presented to the fingertip.

[0046] In the configuration described in (11) above, the control unit, which receives motion information detected by the detection unit, controls the tracing sensation presentation device, thereby enabling the presentation of a tracing sensation based on the movements of the user or a character in the virtual space. [Effects of the Invention]

[0047] According to the present invention, it is possible to provide a tracing sensation presentation device and a virtual space display device that can modulate the roughness and texture perceived by the fingertips. [Brief explanation of the drawing]

[0048] [Figure 1] This is a schematic front view showing a first embodiment of the tracing sensation presentation device according to the present invention. [Figure 2] This is a plan view showing a rotating disc in a first embodiment of the tracing sensation presentation device according to the present invention. [Figure 3] This is a cross-sectional view showing a rotating disc in a first embodiment of the tracing sensation presentation device according to the present invention. [Figure 4] This is an explanatory diagram illustrating the state of the modulation in the first embodiment of the tracing sensation presentation device according to the present invention. [Figure 5] This is a graph showing the modulation state in the first embodiment of the tracing sensation presentation device according to the present invention. [Figure 6] This is a plan view showing the rotating disk in a tracing sensation presentation device. [Figure 7] This is a plan view showing another example of the rotating disk in the first embodiment of the tracing sensation presentation device according to the present invention. [Figure 8] This is a plan view showing another example of the rotating disk in the first embodiment of the tracing sensation presentation device according to the present invention. [Figure 9] This is a cross-sectional view showing a rotating disc in a second embodiment of the tracing sensation presentation device according to the present invention. [Figure 10] This is a plan view showing a rotating disc in a third embodiment of the tracing sensation presentation device according to the present invention. [Figure 11] This is a plan view showing a rotating disc in a fourth embodiment of the tracing sensation presentation device according to the present invention. [Figure 12] This is a perspective view showing a rotating disc in a fifth embodiment of the tracing sensation presentation device according to the present invention. [Figure 13] This is a perspective view showing another example of a rotating disk in a fifth embodiment of the tracing sensation presentation device according to the present invention. [Figure 14] This is a schematic front view showing a sixth embodiment of the tracing sensation presentation device according to the present invention. [Figure 15] This is a schematic diagram showing a seventh embodiment of the virtual space display device according to the present invention. [Modes for carrying out the invention]

[0049] Hereinafter, a first embodiment of the tracing sensation presentation device according to the present invention will be described with reference to the drawings. Figure 1 is a schematic front view showing the tracing sensation indicator device in this embodiment. In the figure, reference numeral 1 denotes the tracing sensation indicator device.

[0050] The tracing sensation presentation device 1 according to this embodiment is a device that presents a tracing sensation by touching it with a fingertip. The tracing sensation presentation device 1 is worn directly on the finger. The tracing sensation presentation device 1 can fix the fingertip to the device 1 to the extent that it can present a tracing sensation to the fingertip. The position in which the tracing sensation presentation device 1 is worn can be freely adjusted according to the length of the user's finger. As shown in Figure 1, the tracing sensation presentation device 1 according to this embodiment includes a rotating disc 10 that contacts the fingertip, a rotation drive unit 2, a position regulating unit 3, a detection unit 4, and a control unit 5.

[0051] The rotating disk 10 makes contact with the fingertip, providing a tactile sensation. The rotating disk 10 will be described later. The rotary drive unit 2 is connected to the rotating disk 10 via a rotating shaft 21. The rotary drive unit 2 rotates the rotating disk 10. The rotating shaft 21 rotates around the central axis 10o. The rotary drive unit 2 may be capable of driving the rotating disk 10 in both forward and reverse directions. For example, a dual-shaft motor may be used for the rotary drive unit 2. A DC motor may be used for the rotary drive unit 2. The rotary drive unit 2 is connected to a power supply. In Figure 1, the power supply is shown as an integral part of the control unit 5. The power supply may be connected separately from the control unit 5.

[0052] The position regulating unit 3 regulates the fingertip position relative to the rotating disc 10. The position regulating unit 3 sets the fingertip position that contacts the rotating disc 10 and can fix the finger in that set position. The position regulating unit 3 sets the finger position so that the pad of the fingertip is always in contact with the center of the rotating disc 10. The position regulating unit 3 includes a regulating unit 31 that restricts the fingertip position relative to the rotating disc 10, and a fixing unit 32 that fixes the finger in a predetermined position as determined by the regulating unit 31.

[0053] The restricting part 31 restricts the tip position relative to the rotating disc 10. The restricting part 31 is a finger fixing base positioned at a predetermined distance from the rotating disc 10. The restricting part 31 contacts the finger at a position closer to the palm than the position where it contacts the rotating disc 10. The restricting part 31 contacts the finger at the ventral position, just like the finger that contacts the rotating disc 10.

[0054] The fixing part 32 secures the finger that has been positioned in a predetermined location by the restricting part 31. The fixing part 32 is configured to be able to fix and release the finger that is placed on the restricting part 31, which is a fixing base. The fixing part 32 can be exemplified by, for example, a hook-and-loop fastener. The fixing part 32, which is a hook-and-loop fastener, can be wrapped around the outer circumference of the finger so as to cover the finger that is stretched between the restricting part 31 and the rotating disc 10. The fixing part 32 can wrap around the outer circumference of the finger and the tracing sensation presentation device 1 together. The fixing part 32 can fix one finger to the tracing sensation presentation device 1.

[0055] The fixing part 32 allows for adjustment of the contact force between the fingertip and the rotating disc 10 by adjusting the winding length, etc. For example, if the fixing part 32 is wound tightly, the pressing force applied from the fingertip to the rotating disc 10 in the direction of the central axis 10o increases. Furthermore, the fixing part 32 may have adjustment marks, such as markings indicating the winding length, to serve as a guide for adjusting the contact force between the fingertip and the rotating disc 10.

[0056] The position regulating unit 3 is not limited to the above configuration, as long as it can regulate the fingertip position relative to the rotating disk 10. For example, a tubular configuration having an axis in the direction toward the rotating disk 10 can also be adopted.

[0057] The detection unit 4 includes an encoder 41 and a load cell 42. The encoder 41 detects the rotation state of the rotating shaft 21. The encoder 41 is connected to the control unit 5. The encoder 41 outputs the rotation state of the rotating shaft 21 to the control unit 5. The encoder 41 may also be a magnetic encoder. The load cell 42 measures the pressing force in the direction of the central axis 10o on the rotating disk 10. The load cell 42 is connected to the control unit 5. The load cell 42 outputs the measurement result of the pressing force to the control unit 5.

[0058] Figure 2 is a plan view showing the rotating disc in the tracing sensation presentation device of this embodiment. Figure 3 is a cross-sectional view showing the rotating disc in the tracing sensation presentation device of this embodiment. The rotating disk 10 rotates around its central axis 10o, as shown in Figures 1 to 3. The diameter of the rotating disk 10 is not greater than the width of a finger. The diameter of the rotating disk 10 can be approximately 5 mm to 15 mm, or approximately 12 mm. The rotating disk 10 has a contact surface 11 and a convex portion (contact portion) 12.

[0059] The contact surface 11 has a circular contour when viewed in the direction of the central axis 10o. The contact surface 11 is a surface that intersects the central axis 10o. The contact surface 11 is a plane perpendicular to the central axis 10o. The contact surface 11 is provided on one surface of the rotating disk 10, for example, over the entire surface. The rotating shaft 21 is connected to the opposite surface of the contact surface 11 on the rotating disk 10, i.e., the back surface. The protrusion 12 is formed on the contact surface 11 as a ridge. When viewed in the direction of the central axis 10o, the protrusion 12 is formed on the contact surface 11 as a straight line passing through the central axis 10o and extending radially. The contact surface 11 is formed so that it is recessed around the protrusion 12. A bottom surface 19 is formed in the recessed portion around the protrusion 12.

[0060] The bottom surface 19 is a surface parallel to the contact surface 11. Both ends of the protrusion 12 are connected to the peripheral edge 11r. The peripheral edge 11r is formed around the entire circumference of the rotating disk 10. The inner circumference of the peripheral edge 11r is formed on a parallel surface at the same height as the contact surface 11. The outer circumference of the peripheral edge 11r is rounded towards the side surface of the rotating disk 10. The width dimension of the protrusion 12 is constant along the radial direction of the rotating disk 10 on which the protrusion 12 extends. The width dimension of the protrusion 12 can be, for example, about 1 mm.

[0061] The top 12a of the protrusion 12 is formed on a surface parallel to the contact surface 11. The height of the top 12a in the direction along the central axis 10o is constant along the radial direction of the rotating disk 10 on which the protrusion 12 extends. Corners 12b and 12c are formed at the widthwise ends of the protrusion 12. Corners 12b and 12c are formed as straight lines extending substantially along the radial direction of the rotating disk 10 when viewed in the direction of the central axis 10o. Corners 12b and 12c are parallel to each other. Corners 12b and 12c form steps at the widthwise ends of the protrusion 12. Corners 12b and 12c each form steps at the ends of the protrusion 12 in the rotational direction. Corners 12b and 12c have cross-sectional shapes that result in steps at approximately right angles. The cross-sectional angles of the steps formed by corners 12b and 12c are the same.

[0062] The corner 12b is formed by the intersection of the top 12a and the side surface 12d. The side surface 12d is perpendicular to the contact surface 11. The side surface 12d is parallel to the central axis 10o. The corner portion 12c is formed by the intersection line of the top portion 12a and the side portion 12e. The side portion 12e is perpendicular to the contact surface 11. The side portion 12e is parallel to the central axis 10o. The angle at which the top 12a and the side surface 12d intersect is equal to the angle at which the top 12a and the side surface 12e intersect. In other words, the convex portion 12 is formed with equal inclines for the step on the front side in the direction of rotation and the step on the rear side in the direction of rotation.

[0063] As shown in Figure 1, the tracing sensation presentation device 1 of this embodiment fixes the finger to the rotating disc 10 by the position regulating unit 3. At this time, the finger is fixed in a position where the pad of the fingertip is in contact with the contact surface 11. When the fingertip comes into contact with the contact surface 11, the top 12a of the convex portion 12 on the right side of the central axis 10o, with the corner 12b as the boundary, makes contact with the skin of the fingertip in a way that causes it to indent. The top 12a of the convex portion 12 on the left side of the central axis 10o, with the corner 12c as the boundary, makes contact with the skin of the fingertip in a way that causes it to indent.

[0064] In this state, the control unit 5 drives the rotation drive unit 2 to rotate the rotating disk 10. At this time, the encoder 41 detects the rotation state of the rotation shaft 21 and outputs it to the control unit 5. Simultaneously, the load cell 42 measures the pressing force in the direction of the central axis 10o on the rotating disk 10 and outputs it to the control unit 5.

[0065] As the rotating disk 10 rotates, the protrusions 12 rotate around the central axis 10o. When the direction of rotation of the rotating disk 10 is the arrow R shown in Figure 2, in the figure, the corner 12b of the protrusion 12 on the right side of the central axis 10o rotates in the forward direction of rotation. Similarly, the corner 12c of the protrusion 12 on the left side of the central axis 10o rotates in the forward direction of rotation. The protrusion 12 rotates along the same plane as the contact surface 11, with its top 12a moving parallel to it. When the protrusion 12 rotates in the rotational direction R, the corner 12b of the protrusion 12 on the right side of the central axis 10o moves in the rotational direction R while making contact with the skin of the fingertip in a way that causes an indentation. The corner 12c of the protrusion 12 on the left side of the central axis 10o moves in the rotational direction R while making contact with the skin of the fingertip in a way that causes an indentation.

[0066] Then, at the convex portion 12 located to the right of the central axis 10o shown in Figure 2, the contact position of the corner 12b that first struck the skin in the forward direction of rotation R moves in the direction of rotation R. In other words, at the convex portion 12, the corner 12b first strikes the skin in the direction of rotation R, pushing in, and continuously moves across the surface of the skin in the direction of rotation R. At the skin surface of the fingertip, the corner 12b of the convex portion 12 continues to strike, providing a continuous stimulus that moves across the fingertip. At the fingertip, the stimulus that moves along with the rotation of the connecting surface 11 continues.

[0067] Similarly, at the convex portion 12 located to the left of the central axis 10o shown in Figure 2, the contact position of the corner 12c that first strikes the skin in the forward direction of rotation R moves in the direction of rotation R. In other words, at the convex portion 12, the corner 12c first strikes the skin in the direction of rotation R, pushing in and continuously moving across the surface of the skin in the direction of rotation R. On the skin surface of the fingertip, the corner 12c of the convex portion 12 continues to strike, providing a continuous stimulus that moves across the fingertip. At the fingertip, the stimulus continues to move in accordance with the rotation of the connecting surface 11.

[0068] Focusing on a single point on the fingertip, as the rotating disk 10 completes one revolution, the movement of corner 12b in the rotational direction R and the movement of corner 12c in the rotational direction R are repeated in sequence. In other words, corners 12b and 12c are perceived by the fingertip as a planar pattern separated by a distance RD (see Figure 2) in the rotational direction R. Thus, as the rotating disk 10 rotates, the stimulus to the fingertip moves periodically and changes position while maintaining the planar pattern. The pattern stimulus along the rotational direction R rotates and moves at a constant speed. This predetermined speed of pattern stimulus presents a predetermined tracing sensation to the fingertip.

[0069] At this time, the stimuli from corners 12b and 12c must be separated by a distance RD (see Figure 2) along the rotational direction R. The separation distance RD is set in an arc shape along the rotational direction R, as shown in Figure 2. The separation distance RD must be set to be greater than the two-point discrimination threshold of the fingertip. By setting the separation distance RD to be greater than the two-point discrimination threshold of the fingertip, the stimuli from corners 12b and 12c are recognized by the fingertip as a planar pattern.

[0070] By rotating the rotating disc 10, the stimulation to the fingertips can be perceived by the fingertips as a roughness sensation due to the spatially periodic change in the stimulus movement speed (pattern movement speed). The stimulation to the fingertips is provided by the movement of corners 12b and 12c. In this way, repeated stimulation caused by the movement of corners 12b and 12c can provide the fingertip with a predetermined tactile sensation, that is, a feeling of rough texture.

[0071] Furthermore, the control unit 5 controls the drive of the rotation drive unit 2, modulating the rotation speed of the rotating disc 10. This changes the speed at which stimuli move from the corners 12b and 12c. This change in rotation speed modulates the sensation of roughness perceived by the fingertips.

[0072] The tracing sensation presentation device 1 of this embodiment can modulate the roughness perceived by the fingertip by modulating the rotation speed of the rotating disk 10. By changing the rotation speed of the rotating disk 10, the perceived stimulus movement speed (pattern movement speed) associated with roughness can be altered, thereby causing the user to perceive a change in the stimulus on their fingertips. Therefore, by modulating the rotation of the rotating disk 10, the perceived roughness on the fingertips can be modulated.

[0073] Stimulus modulation is thought to occur when the rotating disk 10 is rotating quickly, leading to the perception of a stronger or faster stimulus, resulting in a rougher sensation. Conversely, stimulus modulation is thought to occur when the rotating disk 10 is rotating slowly, leading to the perception of a weaker or slower stimulus, resulting in a smoother sensation.

[0074] The rotation speed changes the number of corners 12b, 12c that pass (contact) a single point of the finger per rotation. The feeling of tracing is thought to be related to the number of corners 12b, 12c that pass (contact) a single point of the finger per unit time. Therefore, the rotation speed and the number of protrusions (contact points) 12 affect the range of roughness that can be presented by the rotating disk 10.

[0075] In this embodiment, an experiment was conducted to verify the relationship between the rotation speed of the rotating disk 10 and the perceived roughness of the tracing sensation presentation device 1. The rotating disk 10 is sometimes called a slit-shaped disk. Due to its structure, the slit-shaped disk is thought to generate vibrations proportional to the number of linear protrusions 12 and the rotation speed when it rotates. From this, it can be considered that the more protrusions 12 there are and the higher the rotation speed, the smoother the sensation may be.

[0076] Figure 4 is a diagram illustrating an experiment to investigate the modulation state in the tracing sensation presentation device of this embodiment. Specifically, the rotating disk 10 was fabricated using 3D printer resin (Standard Resin White, Formlabs). The diameter of the rotating disk 10 was set to 12 mm so as not to exceed the width of a finger and to cover the contact area when tracing an object. The weight of the tracing sensation presentation device 1, excluding the circuitry, is 21.5 g.

[0077] <Presentation of tracing guidelines> To verify the stimulus presentation by the tracing sensation presentation device 1, it is necessary to present a standard for tracing sensation prior to the stimulus presentation by the tracing sensation presentation device 1. To present the standard for tracing sensation, a linear slider (RSA0N11M9A0K, AlpsAlpine) LS and sandpaper SP were used, as shown in Figure 4. The linear slider LS was used to control the tracing speed and tracing distance with the fingertip. Additionally, sandpaper SP was adopted as an evaluation index for the sensation presented by the tracing sensation presentation device 1.

[0078] The standard for tracing feel was established by having the user trace sandpaper SP with their fingertip. At this time, the linear slider LS was used to restrict the movement speed (tracing speed) and the distance (tracing distance) of the fingertip so that they did not change.

[0079] In the experiment, participants traced a linear slider LS from one end to the other three times, in time with an audio cue that played every second. The audio cue was played a total of seven times per trial. The first sound indicated the start, and the seventh sound indicated the end. The measured distance traveled on the linear slider was 95 mm. Therefore, assuming a constant tracing speed, the tracing speed would be 95 mm / sec.

[0080] For the experiment, seven different grit sizes of sandpaper (SP) were prepared: #60, #120, #240, #400, #800, #1500, and #3000. In the experiment, the sandpaper was numbered from 1 to 7, from smoothest to coarsest. The #1500 grit sandpaper was numbered 2, and the #120 grit sandpaper was numbered 6. To minimize the effects of wear, the sandpaper was replaced with a new one each time a participant changed.

[0081] Next, I will explain the experimental conditions.

[0082] <Experimental conditions> The experimental conditions consist of two factors: the number of protrusions 12 on the rotating disk 10 and the rotational speed. To investigate the effect of the number of protrusions 12 on the rotating disk 10, we first examined the effect of the presence or absence of protrusions 12. As shown in Figures 2 and 3, a rotating disk 10 with one protrusion 12 was used, and as shown in Figure 6, a rotating disk 10 without a protrusion 12 was used. The surface of the rotating disk 10 that forms the contact surface 11 was polished smooth with #3000 grit sandpaper.

[0083] The rotational speed of the rotating disk 10 was set under three conditions. The first, Middle condition, was based on a rotational speed where the peripheral speed of the rotating disk 10 was equal to 36% of the tracing speed. The second, Low condition was set to a rotational speed 0.5 times that of the Middle condition. The third, High condition was set to a rotational speed twice that of the Middle condition. The following describes the case where the experimental conditions are a total of six conditions, which are the combination of two disk conditions and three rotation speed conditions.

[0084] <Experimental Procedure> As a preliminary step to the experiment, participants first practiced using a scale to trace sandpaper with a pressing force of approximately 50 gf. Next, the tracing sensation indicator device 1 was attached to the index finger of the right hand, and the contact force between the fingertip and the rotating disc 10 was adjusted to approximately 50 gf based on the value of the load cell 42 of the tracing sensation indicator device 1. At this time, the contact force was adjusted by changing the fixing position (wrapping position) of the hook-and-loop fastener (Velcro®), which is the fixing part 32. Furthermore, by marking the fixing position (wrapping position) on the hook-and-loop fastener (Velcro®), which is the fixing part 32, this procedure could be omitted when reattaching the device. Finally, with the tracing sensation presentation device 1 attached, the participant placed the area near the third joint on the linear slider LS and practiced moving their finger left and right in accordance with the audio cues. After completing the above steps, the experiment was conducted.

[0085] First, participants attached the tracing sensation indicator device 1 to their index finger and secured it to their finger by tightening the fixing part 32, using the mark they had previously made as a guide. Next, with their fingers placed on the linear slider LS, participants performed tracing movements in accordance with audio cues. During this time, the rotating disc 10 in contact with the fingertips was rotated to provide a tracing sensation. After the tracing sensation presentation device 1 was removed, participants were asked to select the number of the sandpaper SP that best matched the sensation presented by the tracing sensation presentation device 1. The above procedure was repeated for each experimental condition. During the experiment, to mitigate auditory influences, white noise was played simultaneously with audio cues through headphones. These results are shown in Figure 5.

[0086] Figure 5 is a graph showing experimental results investigating the modulation state in the tracing sensation presentation device of this embodiment. In Figure 5, the vertical axis represents the Rating, or roughness, with higher values ​​indicating roughness and lower values ​​indicating smoothness. In Figure 5, the results for a rotating disk 10 with a single protrusion 12 are shown as the "1-line condition." The results for a rotating disk 10 with a flat surface and no protrusion 12 are shown as the "No-line condition." The rotation speed conditions are also shown as Low, Middle, and High.

[0087] In Figure 5, for each data point, the line denoted by Me represents the median, and the triangle represents the mean. This data was subjected to sorted-rank-transformed analysis of variance (ART-ANOVA)

[10] and multiple comparisons using Bonferroni correction. As shown in Figure 5, a significant difference was observed between the No-line condition and the 1-Line condition (p=0.001) for the disk factor. A significant difference was observed between the High condition and the Low condition for the velocity factor.

[0088] As shown in Figure 5, under both the 1-line and No-line disk conditions, the Rating on the vertical axis moves upward as the rotation speed condition changes from Low, Middle, and High. In other words, when the disk conditions are 1-line and No-line, the perceived roughness increases as the rotation speed condition changes from Low, Middle, and High.

[0089] These results suggest that a rotating disk 10 with one protrusion 12 is perceived as coarser than a rotating disk 10 without a protrusion 12. At the same time, it was suggested that, under the same disk conditions, the perceived coarser texture increases with increasing rotational speed. The inventors hypothesized that as rotational speed increases, the frequency of vibrations generated at the fingertips increases, resulting in a smoother sensation; however, the findings obtained in this study contradicted this hypothesis.

[0090] One possible reason for this is that as the rotation speed increases, the amount of vibration generated on the fingertip skin increases, which may have led to the interpretation that the sensation was rough. In addition, some experimental participants commented that they felt vibration in addition to rotation. As the rotation speed increases, the vibration of the motor itself also increases, so this may also be contributing to the cause. It should be noted that this vibration may also be the reason why speed dependence is observed even under the No-line condition, but on the other hand, there was almost no difference between the Middle and High conditions despite the difference in vibration intensity. In the interaction, there is a significant difference between the Low and High conditions under the 1-line condition.

[0091] Hereinafter, other examples of the first embodiment of the tracing sensation presentation device according to the present invention will be described with reference to the drawings. Figure 7 is a plan view showing the rotating disc of a tracing sensation presentation device in another example of this embodiment. In this example, the number of protrusions (contact portions) 12 is different, and the same reference numerals are used for other components corresponding to the first embodiment described above, and their descriptions are omitted.

[0092] In this example, the rotating disk 10 has two protrusions 12 on its contact surface 11, equidistant from the central axis 10o, as shown in Figure 7. The two protrusions 12 are parallel to each other. Neither of the two protrusions 12 passes through the central axis 10o. When viewed along the central axis 10o, the two protrusions 12 are arranged point-symmetrically with respect to the central axis 10o. The rotating disk 10 has a bottom surface 19 formed on all parts except for the two protrusions 12 and the peripheral edge 11r. The tops 12a and 12f of the two protrusions 12 are both formed on surfaces parallel to the contact surface 11. The tops 12a and 12f are both at the same height.

[0093] In the figure, the convex portion 12 shown above the central axis 10o has a corner portion 12b formed by the intersection line with the side surface 12d at the upper end in the width direction of the apex 12a, and a corner portion 12c formed by the intersection line with the side surface 12e at the lower end. Furthermore, the convex portion 12 shown below the central axis 10o in the figure has a corner portion 12g formed by the intersection line with the side surface 12j at the upper end in the width direction of the apex 12f, and a corner portion 12h formed by the intersection line with the side surface 12k at the lower end. Side surfaces 12j and 12k are perpendicular to the contact surface 11. Side surfaces 12j and 12k are parallel to the central axis 10o.

[0094] In this example, as shown in Figure 7, the two protrusions 12 rotate as the rotating disk 10 rotates. When the rotation direction of the rotating disk 10 is the arrow R shown in Figure 7, if we focus on a single point on the fingertip, the movement of corner 12b in the rotation direction R, the movement of corner 12g in the rotation direction R, the movement of corner 12h in the rotation direction R, and the movement of corner 12c in the rotation direction R are repeated in sequence as the rotating disk 10 completes one revolution.

[0095] The stimuli from corner 12b and corner 12g are separated by a distance RD along the rotational direction R. The stimuli from corner 12g and corner 12h are separated by a distance RD along the rotational direction R. The stimuli from corner 12h and corner 12c are separated by a distance RD along the rotational direction R. The stimuli from corner 12c and corner 12b are separated by a distance RD along the rotational direction R. Note that these separation distances RD can be different in magnitude. These separation distances RD can also be the same in magnitude. All separation distances RD are set to be greater than the two-point discrimination threshold.

[0096] The movement of corners 12b, 12g, 12h, and 12c provides continuous or intermittent stimulation, which can give the fingertips a predetermined tactile sensation, i.e., a rough texture.

[0097] Furthermore, the control unit 5 controls the drive of the rotation drive unit 2, modulating the rotation speed of the rotating disk 10. This changes the speed at which stimuli travel from corners 12b, 12g, 12h, and 12c. This change in rotation speed modulates the sensation of roughness perceived by the fingertips.

[0098] Furthermore, as another example of the first embodiment of the tracing sensation presentation device according to the present invention, a configuration in which four protrusions (contact portions) 12 are provided can be illustrated, as shown in Figure 8. In this example as well, as the rotating disk 10 rotates, the contact positions of the four protrusions 12 move successively in the rotational direction R, and the continuous or intermittent repeated stimulation can give the fingertips a predetermined tactile sensation, that is, a sense of texture roughness. By modulating the rotational speed of the rotating disk 10, the movement speed changes, and thus the sense of roughness perceived by the fingertips can be modulated.

[0099] In these examples, the change in tracing feel caused by varying the number of protrusions 12 as a disk condition was investigated using the same experimental procedure as in the experiment described above. Here, two additional disk conditions were added to the above experiment to investigate the effects of the presence or absence of protrusions 12 and the number of protrusions 12. These results are shown in Figure 5.

[0100] The following describes the case where the experimental conditions are set to a total of 12 conditions, which are the sum of 4 disk conditions and 3 rotation speed conditions.

[0101] By adding two additional disk conditions, the rotating disk 10, in addition to the configurations shown in Figures 2, 3, and 6, was configured in four ways, as shown in Figures 7 and 8, with a total of four types of configurations using the number of protrusions 12: 0 (No-line condition), 1 (1-line condition), 2 (2-line condition), and 4 (4-line condition). Similar to the experiment described above, Figure 5 shows the results obtained with a rotating disk 10 having two protrusions 12 as the "2-line condition," and the results obtained with a rotating disk 10 having four protrusions 12 as the "4-line condition."

[0102] Multiple comparisons were applied to a total of 12 conditions. For the disk factor, significant differences were observed between the No-line condition and the 1-Line condition (p=0.001), between the No-line condition and the 2-Line condition (p=0.001), and between the No-line condition and the 4-Line condition (p=0.049). Similarly, multiple comparisons showed a significant interaction between the 1-line condition and the 4-line condition in the High-Low condition combination (p=0.041). No significant differences were observed in other combinations. Similarly, significant differences were observed between the High-Low condition and the Speed ​​factor.

[0103] These experimental results suggest that rotating disks 10 with two and three protrusions 12 are perceived as coarser than rotating disks 10 without protrusions 12, and that the perceived coarser texture increases with increasing rotational speed. On the other hand, it was also suggested that as the number of protrusions 12 increases, the tendency to perceive coarser texture weakens more than the tendency to exaggerate coarseness with increasing rotational speed. The inventors hypothesized that as the number of protrusions 12 increases, the frequency of vibrations generated at the fingertips increases, resulting in a smoother sensation. However, the findings obtained in this study contradict this hypothesis.

[0104] One possible reason for this is that the increase in the number of protrusions 12 increases the amount of vibration generated on the fingertip skin, which may have led to the interpretation that the surface was rough. In addition, some experimental participants commented that they felt vibration in addition to rotation. As the rotation speed increases, the vibration of the motor itself also increases, so this may also be contributing to the cause. It should be noted that this vibration may also be the reason why speed dependence is observed even under the No-line condition, but on the other hand, there is almost no difference between the Middle and High conditions despite the difference in vibration intensity.

[0105] Furthermore, the interaction showed a large difference between the Low and High conditions under the 1-line condition, while there was almost no difference under the 4-line condition. Based on this, it may be possible to change the relationship between rotational speed and perceived roughness by increasing the number of protrusions 12 or by using different shapes.

[0106] In this embodiment, by bringing a fingertip into contact with the center of a rotating disc with slit-like irregularities on its surface, a tracing sensation can be presented, and the perceived roughness can be modulated in accordance with changes in rotation speed. In addition, the relationship between the sensation of the stimuli presented by the tracing sensation presentation device and the perceived roughness was verified using sandpaper of different coarseness as an evaluation index. As a result, it was shown that the surface felt rougher as the rotation speed increased. On the other hand, it was also suggested that this tendency weakened as the number of lines in the slits of the disc increased.

[0107] A second embodiment of the tracing sensation presentation device according to the present invention will be described below with reference to the drawings. Figure 9 is a cross-sectional view showing the rotating disc in the tracing sensation presentation device of this embodiment. In this embodiment, the difference from the first embodiment described above is in the contact portion. Other components corresponding to the first embodiment described above are denoted by the same reference numerals and their descriptions are omitted.

[0108] As shown in Figure 9, the tracing sensation presentation device 1 of this embodiment has a rotating disc 10 that has a recess 13 instead of a convex portion 12 as a contact portion. The recess 13 (contact portion) is formed with substantially the same contour shape as the convex portion 12 of the first embodiment when viewed in the direction along the central axis 10o. Both ends of the recess 13 reach the inner circumference of the peripheral edge 11r. The recess 13 has a bottom portion 13a formed with the same contour shape as the top portion 12a of the first embodiment when viewed in the direction along the central axis 10o. The recess 13 has side surfaces 13d and 13e at its widthwise ends that face each other across the central axis 10o.

[0109] Sides 13d and 13e are planar. Sides 13d and 13e are parallel to the central axis 10o. Sides 13d and 13e are perpendicular to the contact surface 11. Sides 13d and 13e form corners 13b and 13c as lines of intersection with the contact surface 11.

[0110] Corners 13b and 13c are formed as straight lines extending approximately radially when viewed in the direction of the central axis 10o. Corners 13b and 13c are formed as straight lines extending approximately radially from the vicinity of the central axis 10o to the rotating disk 10. Corners 13b and 12c3 are parallel to each other. Corners 13b and 13c form a step at the widthwise end of the recess 13. Corners 13b and 13c have a cross-sectional shape that results in a nearly right-angle step. The cross-sectional sections of corners 13b and 13c have the same angle as the step.

[0111] In this embodiment, the tracing sensation presentation device 1 fixes the finger to the rotating disc 10 by the position regulating unit 3. At this time, the pad of the fingertip comes into contact with the contact surface 11. When the fingertip comes into contact with the contact surface 11, the contact surface 11 makes contact with the skin of the fingertip in a way that causes it to indent. In the recess 13, the skin indented by the contact surface 11 does not make contact with the corners 13b and 13c, and the skin bulges out towards the bottom 13a inside the recess 13.

[0112] In this state, when the rotating disk 10 is rotated, the recess 13 rotates around the central axis 10o. As the rotating disk 10 rotates, the stepped corners 13b and 13c in the recess 13 move in the rotational direction R, acting as a boundary where they switch between a state in which the skin of the fingertip is released from contact with the contact surface 11 so that it bulges, and a state in which they contact the contact surface 11 and indent the skin of the fingertip.

[0113] When the rotation direction of the rotating disk 10 is the same as the arrow R shown in Figure 2, the corner 13c that is at the rear in the rotation direction R acts in accordance with the corner 12b that is at the front in the rotation direction R. In other words, this corner 13b forms a step as a boundary that contacts the contact surface 11 in a way that causes the skin of the fingertip, which was bulging in the recess 13, to be recessed. Similarly, at a position opposite to the central axis 10o, the corner 13b that is at the rear in the rotation direction R acts in accordance with the corner 12c that is at the front in the rotation direction R. In other words, this corner 13c forms a step as a boundary that contacts the contact surface 11 in a way that causes the skin of the fingertip, which was bulging in the recess 13, to be recessed.

[0114] As the rotating disc 10 rotates, the contact position of the corner 13b that strikes the skin moves in the rotational direction R towards the rear of the recess 13 in the rotational direction R. In other words, in the recess 13, the corner 13b pushes into the skin it strikes and continuously moves across the skin surface in the rotational direction R. On the skin surface of the fingertip, the corner 13b of the recess 13 continues to strike, providing a continuous stimulus that moves across the fingertip. At the fingertip, the stimulus continues to move in accordance with the rotation of the connecting surface 11.

[0115] Similarly, at a position opposite to the central axis 10o, in the rear of the rotational direction R in the recess 13, the contact position of the corner 13c that strikes the skin moves in the rotational direction R. In other words, in the recess 13, the corner 13c pushes into the skin it strikes and continuously moves across the skin surface in the rotational direction R. On the skin surface of the fingertip, the corner 13c of the recess 13 continues to strike, providing a continuous stimulus that moves across the fingertip. At the fingertip, the stimulus continues to move in accordance with the rotation of the connecting surface 11.

[0116] Focusing on a single point on the fingertip, as the rotating disc 10 completes one revolution, the movement of the rear corner 13b in the recess 13 in the direction of rotation R, and the movement of the rear corner 13c in the recess 13 in the direction of rotation R, are repeated in sequence. In other words, the corners 13b and 13c are similarly perceived by the fingertip as a planar pattern separated by a distance RD in the direction of rotation R. Thus, as the rotating disc 10 rotates, the stimulus to the fingertip moves periodically and changes position while maintaining the planar pattern. The pattern stimulus along the direction of rotation R rotates and moves at a constant speed. This predetermined speed of pattern stimulus presents a predetermined tracing sensation to the fingertip.

[0117] The separation distance RD must be set to be greater than the two-point discrimination threshold. By setting the separation distance RD to be greater than the two-point discrimination threshold, stimuli from corners 13b and 13c are perceived by the fingertip as a planar pattern. In this way, repeated stimulation caused by the movement of corners 13b and 13c can provide the fingertip with a predetermined tactile sensation, that is, a feeling of rough texture. Furthermore, the rotation speed of the rotating disk 10 is modulated. This changes the speed at which stimuli travel from corners 13b and 13c. This change in rotation speed modulates the sensation of roughness perceived by the fingertips.

[0118] Alternatively, corresponding to the corner 12b of the first embodiment, at the corner 13b in the recess 13 that is forward in the rotational direction R, the position of the skin that initially separates from the contact surface 11 moves in the rotational direction R. In other words, in the recess 13, the corner 13b initially separates the skin that was pressed by the contact surface 11 in the rotational direction R and expands toward the bottom 13a, while continuously moving the surface of the skin in the rotational direction R. On the skin surface of the fingertip, the corner 13b continues to separate from the state in which it was pressed by the contact surface 11, and a continuous stimulus is applied to the fingertip. At the fingertip, the stimulus continues to move in accordance with the rotation of the connecting surface 11.

[0119] At corners 13b and 13c, the step provides both a stimulating sensation of pressing the fingertip in and a stimulating sensation of separating it from the contact surface 11. Both of these stimuli provide the fingertip with a predetermined tactile sensation, i.e., a sense of rough texture. Furthermore, the protrusions 12 also provide both of these stimuli to the fingertips, presenting a predetermined tactile sensation, i.e., a sense of rough texture, to the fingertips.

[0120] In this embodiment, the same effects as those of the above-described embodiment can be achieved.

[0121] A third embodiment of the tracing sensation presentation device according to the present invention will be described below with reference to the drawings. Figure 10 is a plan view showing the rotating disc in the tracing sensation presentation device of this embodiment. The only difference in this embodiment from the first embodiment described above is the protrusions. Other components corresponding to those in the first embodiment described above are denoted by the same reference numerals and their descriptions are omitted.

[0122] In this embodiment, the rotating disk 10 has a cross-shaped projection 12. Alternatively, as shown in Figure 10, the projection 12 extends radially outward in all four directions from the central axis 10o (center) of the rotating disk 10. The four protrusions 12 extending radially from the central axis 10o each have a corner 12b facing forward in the rotational direction R, formed at the intersection of the top 12a and the side surface 12d. Furthermore, the four protrusions 12 extending radially from the central axis 10o each have a corner 12c facing backward in the rotational direction R, formed at the intersection of the top 12a and the side surface 12e. The four protrusions 12 have an equal spacing RD in the rotational direction R. In this embodiment, the spacing RD of the protrusions 12 is half that of the protrusions 12 in the first embodiment.

[0123] The tracing sensation presentation device 1 of this embodiment rotates the rotating disc 10, similar to the first embodiment, to provide a rotational stimulus to the fingertip from four corners 12b. The repeated stimulus caused by the movement of the four corners 12b provides the fingertip with a predetermined tactile sensation, that is, a feeling of rough texture. Furthermore, the rotation speed of the rotating disk 10 is modulated. This changes the speed at which stimuli travel from the four corners 12b. This change in rotation speed modulates the perception of roughness by the fingertips.

[0124] In this embodiment, the same effects as those of the above-described embodiment can be achieved.

[0125] A fourth embodiment of the tracing sensation presentation device according to the present invention will be described below with reference to the drawings. Figure 11 is a plan view showing the rotating disc in the tracing sensation presentation device of this embodiment. The difference in this embodiment from the second embodiment described above is the aspect of the recess. Other components corresponding to the second embodiment described above are denoted by the same reference numerals and their descriptions are omitted.

[0126] In this embodiment, the rotating disk 10 has recesses 13 formed in a cross shape, corresponding to the protrusions 12 of the third embodiment, as shown in Figure 11. Furthermore, the recesses 13 in this embodiment are intermittently arranged in the radial direction of the rotating disk 10. Each recess 13 has a substantially circular contour shape when viewed along the central axis 10o. Each recess 13 has a cylindrical side surface 13d. Furthermore, in the rotating disk 10, the four recesses 13 that extend intermittently radially from the central axis 10o all have corners 13b formed at the intersection of the contact surface 11 and the side surface 13d. The contour shape of each corner 13b, when viewed in the direction along the central axis 10o, is circular. In this embodiment, unlike the separation distance RD, the distance between adjacent recesses 13 in the radial direction of the rotating disk 10 does not need to be set to be greater than the two-point discrimination threshold.

[0127] The tracing sensation presentation device 1 of this embodiment rotates the rotating disc 10, similar to the second embodiment, to provide a rotational stimulus to the fingertip from the corners 13b that are located at the rear and front of the rotational direction R, respectively, among the four intermittent recesses 13. The repeated stimulus caused by the movement of the four intermittent corners 13b provides the fingertip with a predetermined tactile sensation, that is, a feeling of rough texture. Furthermore, the rotation speed of the rotating disc 10 is modulated. This changes the speed at which stimuli travel from the four intermittent corners 12b. This change in rotation speed modulates the sensation of roughness perceived by the fingertips.

[0128] In this embodiment, the same effects as those of the above-described embodiment can be achieved.

[0129] A fifth embodiment of the tracing sensation presentation device according to the present invention will be described below with reference to the drawings. Figure 12 is a perspective view showing the rotating disc in the tracing sensation presentation device of this embodiment. The only difference in this embodiment from the first to fourth embodiments described above is the contact portion. Other components corresponding to the first to fourth embodiments described above are denoted by the same reference numerals and their descriptions are omitted.

[0130] In this embodiment, the rotating disk 10 has four protrusions 12 that extend radially from the central axis 10o, as shown in Figure 12, corresponding to the protrusions 12 of the third embodiment. The protrusions 12 are formed as straight lines such that the tops 12a coincide with the corners 12b. Therefore, the contact surface 11 is formed as a trajectory due to the contact of the tops 12a or corners 12b. The contact surface 11 is a plane perpendicular to the central axis 10o. The height of the four tops 12a along the central axis 10o is the same as the contact surface 11.

[0131] When the rotating disk 10 is rotated in the rotational direction R1, the protrusion 12 has a corner 12b that is in front of the rotational direction R1 and, in the third embodiment, a corner 13c that is in rear of the rotational direction R1. In this embodiment, the peripheral edge 11r is not formed. Therefore, the radially outer side of the protrusion 12 reaches the outer circumferential surface of the rotating disk 10.

[0132] The protrusion 12 has a side surface 12d that faces forward in the rotational direction R1 when the rotating disk 10 is rotated in the rotational direction R1. This side surface 12d is a plane that aligns with the radial direction of the rotating disk 10 and with the central axis 10o. The side surface 12d is perpendicular to the contact surface 11. The side surface 12d reaches the outer circumferential surface on the radially outer side of the rotating disk 10. Along the central axis 10o, the end of the side surface 12d opposite to the contact surface 11 connects to the bottom surface 19. All four side surfaces 12d form steps with the same cross-sectional angle along the rotational direction. The side surface 12d descends at an angle close to a right, steeply cut in the direction normal to the contact surface 11. Here, "descending" means moving in a direction toward the back surface of the rotating disk 10, from the contact surface 11 which is the surface of the rotating disk 10, at a height position along the central axis 10o.

[0133] The protrusion 12 has a side surface 12e that is behind the rotation direction R1 of the rotating disk 10, and this side surface 12e is not parallel to the side surface 12d. The side surface 12e is a plane that runs along the radial direction of the rotating disk 10 and is inclined with respect to the central axis 10o. The side surface 12e slopes gently downward from the contact surface 11 toward the rear bottom surface 19 in the rotational direction R1. The side surface 12e slopes gently downward from the corner 12b toward the rear in the rotational direction R1. The side surface 12e reaches the outer circumferential surface on the radially outer side of the rotating disk 10. All four side surfaces 12e form steps with the same cross-sectional angle along the rotational direction.

[0134] When the rotation of the rotating disk 10 is in the opposite direction to the rotation direction R1, which is the rotation direction R2, the side surface 12e becomes the front side of the protrusion 12. The side surface 12e is connected to the bottom surface 19 in front of the rotation direction R2. In the rotation direction R2, the side surface 12e slopes gently from the bottom surface 19 and rises to connect to the corner 12b. The bottom surface 19 is parallel to the contact surface 11. Side 12d and side 12e are formed to have different inclines. In other words, when switching between rotation direction R1 and rotation direction R2, the inclination of the forward side surfaces 12d and 12e is different.

[0135] The side surfaces 12e and the bottom surface 19 have a fan-shaped outline when viewed along the central axis 10o. Since the top 12a is formed in a straight line that coincides with the corner 13b, the entire surface of the rotating disk 10 is covered by the four side surfaces 12e and the bottom surface 19 when viewed along the central axis 10o. When viewed on the outer circumferential surface of the rotating disk 10, it is formed in a sawtooth shape in the circumferential direction.

[0136] The tracing sensation presentation device 1 of this embodiment rotates the rotating disc 10, similar to the first embodiment, to provide a stimulating sensation that rotates from the four corners 12b to the fingertip. Here, when the rotating disk 10 is rotated in the rotational direction R1, the side surface 12d, which is cut vertically in the rotational direction R1, first makes contact as a step in front of the corner portion 12b in the rotational direction R1. In contrast, when the rotating disk 10 is rotated in the rotational direction R2, the side surface 12e, which slopes gently downward in the rotational direction R2, first makes contact with the corner portion 12b in front of it in the rotational direction R2, acting as a step. In other words, in the rotational direction R2, the fingertip first contacts the side surface 12e and rises gently, and then reaches the corner portion 12b.

[0137] In other words, when switching between rotation direction R1 and rotation direction R2, the inclination of the side surface 12d, which is in the forward position, and the side surface 12e, which is in the backward position, are different, so the stimulation to the fingertips differs depending on the rotation direction R1 and R2. Specifically, when rotation direction R1 is selected, the steep side surface 12d is the first to contact the fingertips, resulting in a strong stimulation. When rotation direction R2 is selected, the gently rising side surface 12e is the first to contact the fingertips, resulting in a comparatively stronger stimulation.

[0138] Therefore, when a step with a steep incline rotates so that it faces forward in rotation direction R1, it can present a rougher sensation compared to when a step with a gentle incline rotates so that it faces forward in rotation direction R2. When a step with a gentle incline rotates so that it faces forward in rotation direction R2, it can present a smoother sensation compared to when a step with a steep incline rotates so that it faces forward in rotation direction R1.

[0139] This allows different stimuli to be applied to the fingertips from the protrusions 12 by switching the rotation of the rotating disc 10 in the forward and reverse directions. Therefore, it is possible to change the roughness and texture simply by switching the rotation directions R1 and R2. Furthermore, by switching the rotation directions R1 and R2 forward and reverse, as well as changing the rotation speed of the rotating disk 10, it becomes possible to modulate the tracing sensation presented to the fingertips in accordance with these changes in rotational state.

[0140] Furthermore, the modulation of the tracing sensation by switching the direction of rotation is also possible even when the top portion 12a has a predetermined width in the direction of rotation and is formed to be thicker than the straight line that coincides with the corner portion 12b. Furthermore, even when a recess 13 is formed as a contact area, by forming side surfaces 13d and 13e with different inclinations depending on the direction of rotation, it becomes possible to switch the roughness and texture depending on the switching of the rotation directions R1 and R2, similar to the case of the convex portion 12 described above.

[0141] In this embodiment, by bringing a fingertip into contact with the center of a rotating disc having milling-drill-like irregularities on its surface, it is possible to provide a tracing sensation while simultaneously modulating the perceived roughness as the direction of rotation changes.

[0142] Hereinafter, another example of the fifth embodiment of the tracing sensation presentation device according to the present invention will be described with reference to the drawings. Figure 13 is a perspective view showing the rotating disc of the tracing sensation indication device in this embodiment. In this example, the number of protrusions (contact portions) 12 is different, and the same reference numerals are used for the other components corresponding to the fifth embodiment described above, and their descriptions are omitted.

[0143] In this example, as shown in Figure 13, there are eight protrusions 12 extending radially from the central axis 10o to the rotating disk 10. Furthermore, there is no bottom surface 19, and the side surface 12e connects to the lower end of the side surface 12d at the front in the rotational direction R2. In other words, the surface of the rotating disk 10 is formed such that eight sets of side surface 12d, corner 12b, and side surface 12e are continuous in the rotational direction R2.

[0144] In this example, the inclination of side surface 12e is gentler than that of side surface 12e in the fifth embodiment. Also, the inclination of side surface 12d is the same as that of side surface 12d in the fifth embodiment and is vertical. Therefore, in this example, the tracing sensation presented in response to the switching of rotation directions R1 and R2 changes more significantly than the tracing sensation presented in response to the switching of rotation directions R1 and R2 in the fifth embodiment.

[0145] In this example, the same effects as those of the fifth embodiment described above can be achieved.

[0146] A sixth embodiment of the tracing sensation presentation device according to the present invention will be described below with reference to the drawings. Figure 14 is a schematic front view showing the rotating disc and power supply in the tracing sensation presentation device of this embodiment. This embodiment differs from the first to sixth embodiments described above in terms of the rotating disk; other corresponding components are denoted by the same reference numerals and their descriptions are omitted.

[0147] As shown in Figure 14, the rotating disk 10 of this embodiment does not have any irregularities formed on its contact surface 11. The rotating disk 10 of this embodiment has a flat contact surface 11, as shown in Figure 6. The rotating disk 10 is made of a conductor such as metal. The contact surface 11 is covered with an insulating film such as resin. A power supply 8 is connected to the rotating disk 10. The power supply 8 is connected to the control unit 5. The power supply 8 can also be integrated with the control unit 5. The power supply 8 can apply voltage to the rotating disk 10 to store electric charge in the rotating disk 10.

[0148] The voltage applied to the rotating disk 10 is uniform across the entire contact surface 11. The entire contact surface 11 is at the same potential. Power supply 8 dynamically changes the voltage applied to the rotating disk 10. Power supply 8 can apply an AC voltage to the rotating disk 10 at a predetermined frequency. Power supply 8 switches between states that fluctuate within a range of approximately 0V to 300V, for example, at approximately 50Hz.

[0149] In this embodiment, a voltage is applied from the power supply 8 to the rotating disk 10 to accumulate charge on the contact surface 11. Since an insulating film is formed on the surface of the contact surface 11, there is no electrical conduction between this charge and the fingertip. Therefore, the charge exerts an attractive force from the contact surface 11 to the fingertip in the direction normal to the contact surface 11. Furthermore, since an insulating film is formed on the surface of the conductor rotating disk 10, when a high voltage is applied to the rotating disk 10, an attractive force is generated between the finger and the contact surface 11 due to the charge accumulated on the contact surface 11. Consequently, the phenomenon of attraction between the skin and the contact surface 11 occurs.

[0150] When power supply 8 applies an AC voltage, the device repeatedly switches between an attached and unattached state at a frequency of 50 Hz, depending on the applied voltage. This dynamic change in the attached state affects the fingertip at 50 Hz, and is therefore transmitted to the fingertip as a 50 Hz vibration.

[0151] In this state, when the rotating disc 10 is rotated, the fingertip and the rotating disc 10 move relative to each other. As the rotating disc 10 rotates, the contact surface 11, which is in a state of suction, and the skin of the fingertip move relative to each other. As the skin repeatedly adheres to and separates from the contact surface 11, the contact surface 11 rotates, causing the skin to periodically alternate between being dragged and not being dragged. In this way, the periodic movement of the adhesive force on the fingertip changes the frictional force on the finger, resulting in a dragging force acting on the fingertip. This changes the frictional sensation at the contact surface 11. Here again, it is only when the contact surface 11 rotates, in addition to applying voltage, that a sensation such as roughness can be presented to the fingertip.

[0152] The adhesive force is related to the frictional force. When the rotating disc 10 is rotated as the skin repeatedly adheres to and separates from the contact surface 11, the skin of the fingertip alternates between being dragged and not dragged at 50 Hz, and the change in frictional force is perceived by the fingertip as a sense of roughness or texture. In this way, electrostatic tactile sensation makes it possible to present a predetermined tracing sensation to the fingertip.

[0153] Furthermore, the rotational speed of the rotating disk 10 is modulated. This changes the speed at which the stimulus dragged by the electric charge moves. This change in rotational speed modulates the roughness sensation perceived by the fingertip, similar to the rotational disk 10.

[0154] In this embodiment, by generating an electrostatic force between the fingertip and the center of the rotating disk while the fingertip is in contact with the disk, it is possible to present a tracing sensation while modulating the perceived roughness at that time.

[0155] Next, a seventh embodiment of the virtual space display device according to the present invention will be described with reference to the drawings. Figure 15 is a schematic diagram showing the virtual space display device of this embodiment. As shown in Figure 15, the virtual space display device 100 of this embodiment includes a tracing sensation indication device 1, a control unit 5, and a detection unit 6. The virtual space display device 100 may also have a display unit that displays the virtual space to the user. The virtual space display device 100 of this embodiment can employ the same configuration as the first to sixth embodiments described above as the tracing sensation presentation device 1, and corresponding components are denoted by the same reference numerals and their descriptions are omitted.

[0156] The virtual space display device 100 is configured to detect movement information of the user or a character in the virtual space and, based on that movement information, to present a tracing sensation that can be modulated by the tracing sensation presentation device 1. The detection unit 6 detects the movement of the user or character in the virtual space as motion information. The detection unit 6 is connected to the control unit 5. The detection unit 6 outputs the detected user or character movement as motion information to the control unit 5.

[0157] When the detection unit 6 detects user movement, the detection unit 6 may be configured integrally with the tracing sensation presentation device 1. In this case, the detection unit 6 can detect the movement of the user's fingers wearing the tracing sensation presentation device 1 as movement information. For example, the detection unit 6 can be a sensor connected to the tracing sensation presentation device 1 to detect its movement, or a camera that photographs the user to detect their movement.

[0158] Here, the term "virtual space" refers to a simulated space that computes the physical environment in fields such as virtual reality and telereality, or to a real physical space that has a master-slave relationship with it. The detection unit 6 can output motion information associated with predetermined visual information in the virtual space to the control unit 5. Here, motion information can consist of contact information indicating whether or not the character's finger and the object are in relative contact in the virtual space, velocity information indicating the relative movement of the character's finger and the object in the virtual space, surface information such as the surface roughness of the object in contact with the character's finger in the virtual space, or deformation of this contact information, velocity information, and surface information. The detection unit 6 is a motion information output unit that outputs motion information to the control unit 5.

[0159] The control unit 5 controls the tracing sensation presentation device 1 based on the motion information input from the detection unit 6. The control unit 5 can also be used as the control unit 5 that controls the tracing sensation presentation device 1 in the above-described embodiment. Here, we refer to the sensation produced by the shear force when sliding a finger across the surface of an object as the "tracing sensation." When we trace the surface of an object, the skin of our fingertips deforms in a tangential direction opposite to the direction of movement. At the same time, it is thought that the tracing sensation is influenced by information such as the amount of movement perceived visually.

[0160] Furthermore, the control unit 5 may have display data for the virtual space and, for example, control the display unit to display virtual space images based on user movement information detected by the detection unit 6. The display unit may consist of, for example, a head-mounted display that displays virtual reality or augmented reality. Alternatively, the display unit may consist of a projection device that displays a virtual space in real space, such as augmented reality.

[0161] In this embodiment, the virtual space display device 100 physically reproduces the skin deformation that occurs when tracing an object in reality by rotating the rotating disk 10, through which the control unit 5 controls the rotation of the rotating disk 10 based on motion information from the detection unit 6. At the same time, the virtual space display device 100 in this embodiment can modulate and present a realistic tracing sensation that corresponds to changes in motion information by controlling the rotation modulation of the rotating disk 10 based on the motion information from the detection unit 6. This makes it possible to perceive a more realistic tracing sensation and realistically present the tracing action that we perform every day to perceive the friction and texture of an object's surface.

[0162] Furthermore, in the present invention, it is also possible to individually select and combine each of the configurations in the above-described embodiments.

[0163] For example, while each embodiment shows a tracing sensation being presented to one fingertip, it is possible to configure the device to present a tracing sensation to other fingers individually by using multiple similar devices. Alternatively, it is possible to configure the device to present the same tracing sensation to multiple fingers. Furthermore, it can be configured to synchronize with and combine with visual effects such as virtual reality, and to present a tracing sensation that corresponds to the distance and speed of fingertip movement.

[0164] In the fourth embodiment, the rotating disc 10 can have convex portions 12 that have the same contour shape as the intermittently formed recesses 13 when viewed along the central axis 10o. Furthermore, if the separation distance RD, which depends on the rotation radius, becomes small and the stimulus cannot be recognized as separate, a contact area may not be formed near the central axis 10o. Here, not providing a contact area means that there does not need to be a step that provides the stimulus. Therefore, near the central axis 10o, it is formed flush with the contact surface 11. Alternatively, near the central axis 10o, it is formed flush with the bottom surface 19. [Explanation of symbols]

[0165] 1...Tracing sensation indicator device 2…Rotating drive unit 3...Position regulation section 4...Detection unit 5…Control Unit 8…Power supply 10… Rotating disk 11…Contact surface 11r... Peripheral area 10o…center axis line 12...Convex part (contact part) 12a,12f…Top 12b,12c,12g,12h...corner 12d,12e,12j,12k…side 13…Recess (contact area) 13a...bottom 13b,13c...corner part 13d,13e…side 19...Bottom 21…Rotation axis 100...Virtual Space Display Device RD…Separation distance (distance) R, R1, R2... Direction of rotation< / url:>

Claims

1. A rotating disc having a contact surface that stimulates the finger, A rotation drive unit that rotates the aforementioned rotating disk, It has, The aforementioned contact surface is capable of varying the stimulation to the finger. A device that provides a sense of tracing, characterized by the following features.

2. The aforementioned contact surface allows for spatially periodic changes in the stimulation to the finger. The tracing sensation presentation device according to feature 1.

3. The contact surface is capable of varying the stimulation in a direction along the contact surface. The tracing sensation presentation device according to feature 2.

4. The contact surface has contact portions formed at a predetermined distance apart in the rotational direction of the rotating disk. The tracing sensation presentation device according to feature 3.

5. The contact portion is a convex or concave portion extending in a direction intersecting the rotational direction of the rotating disk. The tracing sensation presentation device according to feature 4.

6. The contact portion has different inclines for the step formed in front of the rotating disk in the direction of rotation and for the step formed behind the rotating disk in the direction of rotation. The tracing sensation presentation device according to claim 5, characterized by its features.

7. The aforementioned contact surface allows for changes in the stimulation to the finger over time. The tracing sensation presentation device according to feature 1.

8. The contact surface is capable of varying the stimulation in a direction along the normal to the contact surface. The tracing sensation presentation device according to feature 7.

9. A power supply is connected to the rotating disc to apply a voltage at a predetermined frequency that causes a finger to be attracted to the contact surface by electric charge. The tracing sensation presentation device according to feature 8.

10. The frequency of the voltage applied to the rotating disk is greater than the rotational speed of the rotating disk. The tracing sensation presentation device according to feature 9.

11. A detection unit that detects movement information of the user or a character in the virtual space, A tracing sensation presentation device according to any one of claims 1 to 9, A control unit controls the tracing sensation presentation device based on the motion information detected by the detection unit, Having, A virtual space display device characterized by the following features.

Images