Date of publication xxxx 00, 0000, date of current version xxxx 00, 0000.
Digital Object Identifier 10.1109/ACCESS.2017.DOI

Inside Touch: Presentation of Tactile
Feeling Inside Virtual Object Using
Finger-Mounted Pin-Array Display
YUSUKE OTA1 , YUSUKE UJITOKO2 , SHO SAKURAI3 , TAKUYA NOJIMA4 , AND KOICHIHIROTA5 ,(MEMBER, IEEE)
1

Graduate School of Information Systems, The University of Electro-Communications, Tokyo, Japan. (e-mail: yus3554@gmail.com)
NTT Communication Science Laboratories, Nippon Telegraph and Telephone Corporation, Kanagawa, Japan. (e-mail: yusuke.ujitoko@gmail.com)
Graduate School of Information Systems, The University of Electro-Communications, Tokyo, Japan. (e-mail: sho@vogue.is.uec.ac.jp)
4
Graduate School of Information Systems, The University of Electro-Communications, Tokyo, Japan. (e-mail: tnojima@nojilab.org
5
Graduate School of Information Systems, The University of Electro-Communications, Tokyo, Japan. (e-mail: hirota@vogue.is.uec.ac.jp)
23Corresponding author: Yusuke Ota (e-mail: yus3554@gmail.com).

ABSTRACT Previously, tactile displays focused on the tactile presentation of the surface of a virtual
object. In contrast, this study attempts to provide a tactile feeling on the space inside a virtual object whenfingers penetrate it. Our previous study developed a finger-mounted pin-array display with the smallest
pin pitch, representing the highest spatial resolution. Using the display, we attempt to present the tactile
impression of “Rough,” “Grainy,” and “Sparse” which correspond to Japanese onomatopoeia of “ZaraZara,” “Tsubu-Tsubu,” or “Chiri-Chiri” with simple patterned stimuli arranged in 3D space. A series ofexperiments were conducted in this study to determine the following: (1) the stimuli that can provide
users with different tactile impressions inside objects and (2) the effect of tactile display spatial resolution
on the recognition of tactile impressions inside objects. The results clarified that we could provide threedifferent tactile impressions in space with certain stimuli configurations. Besides, the results demonstrated
that participants recognized the tactile impression better with a larger spatial resolution configuration of thedevice. This study reveals a new field of tactile presentation, that is, tactile presentation inside an object.
INDEX TERMS Haptics, Tactile Presentation, Pin-arrays
I. INTRODUCTIONHEN objects are touched in the real world, we cansense various tactile information [1], [2]. We canrecognize the properties of an object’s surface by touching
the object surface [3]. For example, the “Enclosure” or the“Contour following” can be used as one of the exploratory
procedures to sense the global or local shape of objects [4].
Also, we can recognize the surface tactile roughness by“Lateral motion” [5].
Similarly, by touching the surface of a real object, we canindirectly recognize the internal properties. “Pressure” canbe used as one of the exploratory procedures that provide thecompliance or hardness cues of objects [6]. Because fingers
cannot penetrate objects in the real world, the internal properties can only be indirectly inferred based on the interaction
between the fingers and the object surface.
On the other hand, virtual tactile rendering technologies
make it possible to allow users to experience a tactile impression that cannot be experienced in the real world. If

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FIGURE 1: Users touch 3D space inside the object and feeltactile impression.

users utilize wearable haptic displays, such as [7] or [8], thevirtual objects can be penetrated by the fingers, and the user
can directly experience touching the three-dimensional (3D)
space inside a virtual object. As an application of wearable
displays, this study proposes a tactile impression presentation1

Ota et al.: Inside Touch: Presentation of Tactile Feeling Inside Virtual Object Using Finger-Mounted Pin-Array Display

while touching the 3D space inside a virtual object. We provide different tactile impressions such as “grainy” or “rough”
for the 3D homogeneous space inside a solid virtual object(shown in Fig. 1). Presenting various tactile impressions
when touching inside the object can be used to use cases suchas educational material for understanding the structure inside
an object by touching it that is untouchable in the real world.
An example of the use cases is the anatomical materials for
medical training. Conventionally, the utilization of computer
graphics that resort to a vision for the understanding of thehuman body has been developed [9]. Here, in addition tovision, if educational materials that use tactile sensation aredeveloped, there is a possibility that it may lead to further
promotion of understanding. In this use case, users penetrate
the virtual body and touch the various body parts inside
the body which gives users different tactile feelings. To
realize this, it is better that we can freely control the tactile
impression inside objects. However, studies regarding thetactile presentation inside objects have not been conducted,
which may be partially due to the requirement of a displaythat provides distributed haptic feedback with a high spatial
resolution to express the tactile impression of 3D space inside
objects.
Previously, we developed a finger-mounted pin-array display that has the smallest pin pitches, representing the highest spatial resolution ever [10]; using this device, we haveempirically known that we can present the tactile impressionof dusty (“Chiri-Chiri” in Japanese onomatopoeia), grainy(“Tsubu-Tsubu”), or rough (“Zara-Zara”) surfaces for 3D
space inside objects when users receive specific patterned
stimuli that are spatially arranged in space. We conducted
experiments on the three tactile impressions we empiricallyknew by chance to clarify the following items:
The stimuli that can provide users with different tactile
impressions inside objects.
• The effect of tactile display spatial resolution on therecognition of tactile impressions inside objects.

•

II. RELATED WORK
A. TACTILE DISPLAY FOR 2D SURFACE

According to Okamoto et al. [3], the following five principle tactile dimensions are used for the human tactile perception of surface textures: fine/macro roughness, friction,
warmness, and hardness. For example, regarding roughness,
vibrotactile feedback while scanning virtual textured surfaces
is commonly used for rendering the surface roughness [11].
Vibrotactile actuators are now embedded in smartphones
or vibrotactile pens and are highly accessible (e.g., Apple
Watch [12]). Regarding friction, researchers have developed
friction displays that present tangential forces over the user’s
fingers. Force displays such as PHANToM represent theactual frictional force in the tangential direction of a contact
surface [13]. Considering another approach, the frictional
characteristics of a contact surface have been changed byusing a squeeze film generated by ultrasonic vibration [14], a2

SAW [15], or a thin film slider operated by electrostatic force[16].
While these displays present users with surface tactile
sensation, this study focuses on the tactile sensation for 3D
spaces inside virtual objects.
B. HAPTIC FEEDBACK FOR 3D SPACE

For presenting the haptic feedback of 3D spaces, there arevarious approaches including the use of grounded-type device [17], [18], wearable devices [19], or mid-air haptics [20],[21].
Recently, there has been an increasing interest in exploring
mid-air haptics. Focused ultrasound beams can be used tocreate a localized sense of pressure on the fingertip in midair. An array of ultrasound transducers generates a focal
point by individually controlling each transducer’s phase andintensity in a phenomenon known as acoustic radiation pressure. The pressure was used for presenting touchable icons[22], multipoint haptic feedback [23], and three-dimensional
shapes [24]. Although recent studies have attempted to simulate multi-point [23], it is difficult to control the pressure
distribution on the skin at the millimeter scale. Our hypothesis states that devices that can present distributed forces witha high spatial resolution are suitable for presenting tactile
sensations in 3D space inside objects. Thus, we focused on
the pin-array display.
C. PIN-ARRAY DISPLAY

There are two types of pin-array displays: grounded andwearable. Mechanically grounded pin-array displays canpresent robust haptic cues using grounded forces withusers [25]–[27]. However, when users move their hand or finger to any position in the space around, these devices cannot
display the shapes. Namely, the workspace and portability
are constrained. A large interactive mobile workspace may
be useful for the exploration of virtual spaces.
Recently, more haptic system designs considering wearability have started to appear; thus, wearable pin-array displays were developed [28], [29]. To provide users richer
haptic information, the high contact point density is essential [30]. A few studies have attempted to increase the contact
point density [29], [31]. The development of a high-density
pin-array is complex since the pins were integrated with theactuators, such as motors, and the size of the actuator was aconstraint. Due to its difficulty in developing a high-density
pin-array display, no study focuses on presenting the tactile
presentation inside virtual objects, which requires distributed
haptic feedback with a high spatial resolution.
In our previous study [10], we adopted a pneumatic drive
because a pneumatic actuator, or air cylinder, can be a simple
and slim structure; This realized the pin-array displays thathave the highest density. Details regarding the previously
developed display are presented in the next section. As oneof the applications of the high-density pin-array displays, we
focus on the presentation of the tactile presentation inside
the virtual objects. With our high-density display, the present
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Ota et al.: Inside Touch: Presentation of Tactile Feeling Inside Virtual Object Using Finger-Mounted Pin-Array Display

study attempted to present the tactile presentation insidevirtual objects for the first time.
III. APPARATUS
A. SYSTEM OVERVIEW

In the user studies, we used the finger-mounted pin-array
display system, which consisted of a finger-mounted pinarray display, head-mounted display (HMD), sensor, simulator, and air pressure controller (shown in Fig. 2).
B. SYSTEM COMPONENTS
1) Sensor and HMD

Users wore HMD (HTC Vive) on their faces to watch avirtual scene (shown in Fig. 3) and were seated comfortably
in a chair. The index finger of their dominant hand was placedin a pin-array display. In order to reduce the burden on theparticipants due to the weight of the device, the device was
supported from above with stretchable elastic string fromthe ceiling. The position and orientation information of thefingertip were obtained by the magnetic sensor (POLHEMUS 3SPACE FASTRACK) attached to the user’s dominant
hand’s index fingertip. The fingertip position and orientation
information were updated at 120 Hz and sent to a PC via
serial communication from the sensing system.
In addition, users wore noise-canceling headphones to hear
white noise to muffle the external sounds. Users wore an
HTC Vive Controller on the non-dominant hand to answer
the questions in the experiment.
2) Simulator

A simulator (Unity3D) received the position and orientationof the finger from the sensor system. It moved and rotatedthe virtual finger surface according to the sensor value. The
virtual finger had the nodes on the finger surface, whichcorresponds to the 128 pins of the pin-array display. If thecollision of the nodes was detected, the control values weresent to the air pressure controller via serial communication.
3) Pin-array display

The finger-mounted pin-array display (shown in Fig. 4) was
the same as presented in [10]. The update rate and responsetime of the system were 50 Hz and 75 ms. In an informal
study conducted by authors before user studies, we did not
feel the incongruency between the vision and haptics dueto the devices’ refresh rate and response time. The pin’sgrouping condition and the presented stimuli were newly
configured in this study, which is described in the next
sections.
C. GROUPING CONDITION TO SIMULATE SPATIALRESOLUTION

To investigate the effect of the device’s spatial resolution
on the recognition of the tactile impression inside objects,
the density of the pin-array device must be controlled in theexperiment. One of the methods to control the density of pinarrays can be to create three wearable pin-array devices withVOLUME 4, 2016

different spatial resolutions and then experiment with them.
However, that would be problematic because participants
would have to replace the devices during the experiment,
which would make the participant aware of the spatial resolution of the display in use. We need to control the spatial
resolution of the pin-arrays without replacing them.
Thus, this study simulated the spatial resolution of pinarrays by grouping multiple pins into one virtual pin. Threegrouping conditions were used. Grouping 0 used all pins
individually (pin pitch is 1.4 mm, as shown in Fig. 5 (a)).
Grouping 1 grouped three pins into one and enabled/disabled
the three pins together (pin-to-pin distance 2.1 mm, as shownin Fig. 5 (b)). Grouping 2 used four pins as one group (distance between pins 2.8 mm, as shown in Fig. 5 (c)). Pins thatcannot be grouped were not used. The output pressure of eachpin was calibrated in advance. If the pin of the Grouping 0
condition was enabled, it was configured to output 0.08 MPa.
If the pin of the Grouping 1 condition was enabled, each pin
was configured to output 1/3 of 0.08 MPa to make the outputof the representative point equal to Grouping 0. Each pin in
the Grouping 2 condition was configured to output 1/4 of 0.08
MPa based on the same concept previously indicated. Thisadjustment of output depending on the grouping conditions
was required to make the output at each representative point
the same. This could make the density variable the only targetof the comparison variable.
D. STIMULI PATTERN

As a first attempt at presenting tactile sensation inside theobject, this study presented distributed stimuli that can be
represented by spatially periodic stimuli whose control parameters are simple. As spatially periodic stimuli to represent
stimuli inside the virtual objects, we used stimuli patterns
that can be expressed by arranging spheres in a 3D grid
pattern (Fig. 6). The tactile sensation may change dependingon the direction in which the finger is moved, but in theexperiments in this study, the finger movement was restricted
to one direction.
When the nodes (which corresponded to pins) in the simulator overlapped the stimuli, the pin was pushed against
the finger skin at a constant pressure. When there was nooverlap with the stimuli, the pin did not push the skin. Under
Grouping 1 and Grouping 2 conditions, the pins in a certain
group pushed or did not depend on whether the representative
point of the group overlapped the stimuli.
The control parameters of the stimuli patterns could be
the sphere radius and spacing between spheres. However, in
this study, we present the stimulus by configuring the sphereradius while fixing the spacing between the spheres at 2 mm
because it is not efficient to explore the entire configurationof the stimuli patterns.
In advance, it was found in our informal study that a“grainy (Tsubu-Tsubu),” “sparse (Chiri-Chiri),” or “rough(Zara-Zara),” feeling can be felt with the specific sphereradius and spacing of the spheres. This study focused on thesethree specific feelings.
3

Ota et al.: Inside Touch: Presentation of Tactile Feeling Inside Virtual Object Using Finger-Mounted Pin-Array Display

FIGURE 2: Data flow through components of the system and a user.

(a) Grouping0

FIGURE 3: Apparatus(b) Grouping1(c) Grouping2

FIGURE 4: Specification of pin-array haptic device [10]. The
number of pins is 128 and the pin pitch is 1.4 mm

IV. USER STUDIESThe purpose of a series of experiments in this study is toclarify the configuration of stimuli patterns and the spatial
resolution of the device, with which we can present three
types of tactile impressions inside the object. Therefore,
we conducted two experiments (stimuli configuration experiment and stimuli discrimination experiment). The stimuli
configuration experiment was conducted to prepare the stimuli patterns that was used in the discrimination experiment.
In the stimuli discrimination experiment, we answered theresearch questions stated in the Introduction section.
The apparatus described in the previous section was usedin the user studies. This study was approved by the ethics
4

FIGURE 5: Pin-array devices’s grouping conditions to simulate spatial resolution. (a) Grouping0: all pins move independently and the pin pitch is 1.4 mm. (b) Grouping1: three pinsare grouped and the pins move together. The pin pitch is 2.1
mm. (c) Grouping2: four pins are grouped and the pin pitch
is 2.8 mm.

committee of the University of Electro-Communications (approved number: 19005).
A. USER STUDY 1: STIMULI CONFIGURATIONIn this experiment, we investigated the optimized stimuli
patterns for each grouping condition where participants could
feel the three specific tactile sensations. There were tenparticipants with ages ranging from 22 to 26. The participants were all right-handed. All participants had normal orcorrected-to-normal vision and no history of neurological
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FIGURE 7: Screen of presented to participants by headmounted display in user study 1
TABLE 1: Configured radius of stimuli patterns
FIGURE 6: Example of stimuli patterns; (a) radius of stimuli
sphere is 0.1 and (b) radius of stimuli sphere is 0.4.
impairment. All participants were naive to the purpose of
the study. Written informed consent was obtained from eachindividual before the experiments were performed.
There were three tactile sensation conditions and threegrouping conditions. Thus, there were a total of nine conditions. Participants conducted the experiment three times forthe nine conditions, for a total of 27 trials. The presentation
order of 27 trials was pseudo-randomly assigned across participants.
1) Task Design

This experiment used a within-participants design.
On the HMD screen, an explanatory text, a cube witha spherical area inside, a finger object, and a slider foranswering the radius of the stimuli patterns were displayed(Fig. 7). In each trial, the participant touched the inside of
the cube from top to bottom while viewing the cube andthe finger object. Then, the radius of the stimuli patterns
was configured to feel the same as the description of thetactile feeling presented on the screen. The speed of finger
movement was not constrained. In addition, participants wereallowed to move their fingers from top to bottom several
times.
When configuring the radius of stimuli patterns, participants pressed the button on the controller of the nondominant hand. After the adjustment, the enter button waspressed to end the trial. Participants were instructed so thatthey should adjust the radius in terms of tactile sensation
instead of force.

(unit: mm)

Grouping0(pin pitch: 1.4mm)
Grouping1(pin pitch: 2.1mm)
Grouping2(pin pitch: 2.8mm)

Chiri-Chiri(Sparse)Tsubu-Tsubu(Grainy)

Zara-Zara(Rough)0.421 ± 0.056

0.532 ± 0.051

0.697 ± 0.066

0.845 ± 0.103

0.857 ± 0.069

1.203 ± 0.081

0.907 ± 0.098

1.175 ± 0.079

1.320 ± 0.084

effect of the tactile sensation condition (F (2, 171) = 15.27,
p = 7.9 × 10−7 ), and a significant effect of the grouping
condition (F (2, 171) = 44.5, p = 2.7 × 10−16 ). There
was no significant interaction effect between the two factors(F (4, 171) = 0.92, p = 4.5 × 10−1 ). The ANOVA results
suggest differences in the radius for each combination of
the tactile sensation and grouping conditions. Under all thegrouping conditions, the order of the configured radii tended
to be "Chiri-Chiri" < "Tsubu-Tsubu" < "Zara-Zara". Furthermore, there was a tendency for the configured radii tobe larger as the simulated spatial resolution was smaller.
B. USER STUDY 2: STIMULI DISCRIMINATION

Using the configured stimuli patterns in User Study 1, User
Study 2 answered the questions stated in the introduction
section.
The same ten participants were used for this study. For
the trial in this experiment, participants discriminated threetactile feelings with certain grouping conditions. There were
12 trials for each condition; thus, the total number of trials
was 36 for each participant. The configured average radiusvalue was used for each combination of the grouping andtactile sensation conditions, as shown in Table 1.

2) Results

Table1 presents the average configured radius of the stimuli
patterns with the standard error for each tactile sensationand grouping conditions. We performed a two-way repeated
ANOVA of the tactile sensation and grouping condition
factors on the configured radius of the stimuli patterns.
According to the ANOVA results, there was a significant
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1) Task Design

This experiment used a within-participants design.
On the HMD screen, we displayed explanatory text, three
cubes with configured stimuli patterns inside, finger objects,
and three dropdowns for selecting textures (shown in Fig. 8).
Based on the results of Experiment 1, the stimuli patterns
5Ota et al.: Inside Touch: Presentation of Tactile Feeling Inside Virtual Object Using Finger-Mounted Pin-Array Display

for the radii were configured to feel "Chiri-Chiri", "TsubuTsubu", and "Zara-Zara" in random order. The participant
touched the cubes one at a time from top to bottom while
viewing the three cubes and the finger object. Then, theparticipant discriminated which tactile feeling they felt insideof the three cubes and selected the texture from the dropdown category.
The speed of finger movement was not constrained. In
addition, participants were allowed to move their fingers
several times from top to bottom.

(a) Grouping0 (Pin pitch: 1.4mm)(b) Grouping1 (Pin pitch: 2.1mm)

FIGURE 8: Screen of presented to participants by headmounted display in user study 22) Results and Discussions

The result of selection probability is shown in the confusion
matrix for each grouping condition (in Fig. 9). The proportionof discrimination accuracy under the Grouping 0 condition
was 0.8, while those under Grouping 1 and Grouping 2 were0.53 and 0.56, respectively. The result of Grouping 0 demonstrates that we can present three different tactile sensations
inside objects. In contrast, the discrimination was difficult
with Grouping 1 or Grouping 2. To determine whether there
is a difference in the three conditions’ population proportions, we performed a two-proportion z-test with Bonferroni
correction. The null hypothesis indicates that the two population proportions are the same. A significant difference wasfound between the Grouping 0 and Grouping 1 conditions(z = 0.99, p < 0.01). Another significant difference wasfound between the Grouping 0 and Grouping 2 conditions(z = 0.99, p < 0.01). This analysis addressed the concerns
stated in the introduction sections. Namely, the spatial resolution needs to be high to present the tactile sensation inside
an object. In addition, if the radii are 0.421, 0.532, or 0.697,
the users can recognize the “Chiri-Chiri,” “Tsubu-Tsubu,” or“Zara-Zara” impressions.
V. GENERAL DISCUSSIONS
1) Application of Inside Touch

In this study, a novel attempt was made to present the tactile
feeling inside an object. The result indicated the possibility
that we can present at least three kinds of tactile feeling.
6(c) Grouping2 (Pin pitch: 2.8mm)

FIGURE 9: Results of correct answer rate in user study 2.

This section describes the use cases where such a tactile
presentation could be applied. There are two main different
use cases. The first one is the use case where users touch
space inside the solid surface of the object that is untouchable
and the second one is the use case where users touch spaceinside liquid or air.
As one of the examples of the first use case, it can be used
as educational material for understanding the structure inside
an object by touching it that is untouchable in the real world.
Recently, anatomical teaching materials for medical use,teaching materials that utilize the five senses have recently
been developed. For example, the utilization of computer
graphics that resort to a vision for the understanding of thehuman body has been developed [9]. Here, if educational
materials that use tactile sensation are developed, there isa possibility that it may lead to further promotion of understanding. Here, if educational materials that use tactile
sensation are developed, there is a possibility that it may leadto further promotion of understanding. In this use case, users
penetrate the virtual body and touch the various body parts
inside the body which gives users different tactile feelings.
Since the human body is actually "touched" in surgery and
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Ota et al.: Inside Touch: Presentation of Tactile Feeling Inside Virtual Object Using Finger-Mounted Pin-Array Display

palpation in the real world, it may be effective to learn by
associating anatomical material of the body with the sense of
touch. Of course, it can be used not only for the human body
but also for various structural things such as the structure ofbuildings and the structure of industrial products.
The second is the idea of using it for the tactile presentationof space inside liquids and gases. Actually, in the real world,
humans can penetrate the inside of the liquids and gases witha finger and feel the tactile sensation, and thus, if the tactile
sensation inside the virtual liquid or gas can be presented, therealism for the virtual liquid or gas can be enhanced.
These applications have not been tested in this study. We
need to find out how effective the application can be in the
future.
2) Limitations

There are several limitations in this study, Which includes thelimited space of the stimuli patterns used in this study. The
control parameters of the stimuli patterns can be the sphereradius and spacing between spheres; however, we fixed thespacing at a 2 mm constant. We did this to reduce the exploration space of the stimuli patterns and avoid lengthening theexperiment. However, if we made the participant adjust not
only the radius but also the spacing, the configuration of theradius would change. Note, the results were obtained in anenvironment where the spacing was fixed at 2 mm.
Another limitation is the limited tactile feeling addressedin this study. We focused on the three tactile sensations empirically found in our informal experiment. However, there isa possibility that other tactile impressions can be presented
with this high-density device. For example, if we use bothspacing and radius as the control parameters, there is a possibility for more types of tactile feelings to be found. In the
future, we plan to investigate the dimensional composition of
the tactile sensations that can be presented.
VI. CONCLUSIONSThis study used a high-density finger-mounted pin-array
display to provide tactile feeling inside a virtual object whenfingers penetrate it. We conducted a series of experiments.
The results clarified that we could provide three different
tactile impressions in space with certain stimulus configurations. Also, the results demonstrated that participants recognized the tactile impression better with a larger spatial
resolution configuration of the device. This study contributes
to revealing a new field of tactile presentation, that is, tactile
presentation inside an object.
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TAKUYA NOJIMA received a Ph.D. degree in Engineering from The University of Tokyo, Japan, in
2003. He joined the Japan Aerospace Exploration
Agency as a pilot interface and VR simulation
researcher in 2003. He is currently an Associate
Professor with the Department of Informatics University of Electro-Communications, Tokyo, Japan
from 2008. His research interests include haptic
interaction, superhuman sports, human interface,and virtual reality.

YUSUKE OTA is a graduate student at the University of Electro-Communications.

YUSUKE UJITOKO is a researcher at the NTT
Communication Science Laboratories since 2020.
He used to be a member of the R&D Group in Hitachi, Ltd. from 2016 to 2020. He received his PhDfrom the University of Electro-Communications,Japan, in 2020. He received his BE degree in mechanical engineering and MAE degree in interdisciplinary information studies from the Universityof Tokyo, Japan, in 2014 and 2016, respectively.
His research interests include applied haptic perception and haptic interfaces.

KOICHI HIROTA received the B.S. degree fromthe University of Tokyo, Japan, in 1988. He received his Ph.D. degree from the University ofTokyo, in 1994. He was then an assistant professor
with the Toyohashi University of Technology in
1995. In 2000, he was an associate professor with
the University of Tokyo. Currently, he is a professor in the Department of Human Media Systems,
Graduate School of Information Systems, University of Electro-Communications. His researchinterests include haptic rendering and human interfaces. He received several
academic awards.

SHO SAKURAI received a B.E. degree in social
and information studies from the Gunma University in 2007, a M.A.E. degree in inter-disciplinary
information studies in 2010 and a PhD degree inEngineering in 2014 from the University of Tokyo.
Currently, she is a project assistant professor in
Graduate School of Information Systems, the University of Electro-Communications. Her researchinterests are multi-modal/cross-modal interfaces
and human-computer interaction. She is also active as a manga artist for introduction of the latest research of virtual reality
and artificial intelligence.

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