11institutetext: INESC-ID/IST/University of Lisbon
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# Eery Space: Facilitating Virtual Meetings Through Remote Proxemics

Maurício Sousa  Daniel Mendes  Alfredo Ferreira
João Madeiras Pereira  Joaquim Jorge

###### Abstract

Virtual meetings have become increasingly common with modern video-conference
and collaborative software. While they allow obvious savings in time and
resources, current technologies add unproductive layers of protocol to the
flow of communication between participants, rendering the interactions far
from seamless. In this work we introduce Remote Proxemics, an extension of
proxemics aimed at bringing the syntax of co-located proximal interactions to
virtual meetings. We propose Eery Space, a shared virtual locus that results
from merging multiple remote areas, where meeting participants’ are located
side-by-side as if they shared the same physical location. Eery Space promotes
collaborative content creation and seamless mediation of communication
channels based on virtual proximity. Results from user evaluation suggest that
our approach is effective at enhancing mutual awareness between participants
and sufficient to initiate proximal exchanges regardless of their geolocation,
while promoting smooth interactions between local and remote people alike.
These results happen even in the absence of visual avatars and other social
devices such as eye contact, which are largely the focus of previous
approaches.

###### Keywords:

Remote Proxemics, Virtual Meetings, Collaboration, Interaction Design

##  1 Introduction

When people get together to discuss, they communicate in several manners,
besides verbally. Hall [13] observed that space and distance between people
(proxemics) impact interpersonal communication. While this has been explored
to leverage collaborative digital content creation [20], nowadays it is
increasingly common for work teams to be geographically separated around the
globe. Tight travel budgets and constrained schedules require team members to
rely on virtual meetings. These conveniently bring together people from
multiple and different locations. Indeed, through appropriate technology, it
is possible to see others as well as to hear them, making it easier to
communicate verbally and even non-verbally at a distance.

The newest videoconferencing and telepresence solutions support both common
desktop environments and the latest mobile technologies, such as smartphones
and tablet devices. However, despite considerable technological advances,
remote users in such environments often feel neglected due to their limited
presence [22]. Moreover, although verbal and visual communication occur
naturally in virtual meetings, other modes of engagement, namely proximal
interactions, have yet to be explored. This is unfortunate, since proxemics
can enable many natural interactions obviating the need for cumbersome
technology-induced protocol, which is a plague of remote meetings.

In this work, we introduce Eery Space as a virtual construct to bring remote
people together and mediate natural proxemic interactions between participants
as if they were in the same physical place, a mechanism which we call Remote
Proxemics. To this end, Eery Space allow us to merge different rooms into one
virtual shared locus were people can meet, share resources and engage in
collaborative tasks. Building on the notion that people do not need hyper-
realistic awareness devices, such as virtual avatars, to infer the presence of
others [24] and engage in natural social behaviour, Eery Space employs an
iconic representation for remote people. Also, to facilitate virtual meetings,
we propose novel techniques for person-to-person and person-to-device
interactions. We adopt a multiple interactive surfaces environment, which
comprises an ecosystem of handheld devices, wall-sized displays and projected
floors.

In the remainder of the document, we start by reviewing the related work that
motivated our research. We then describe the Eery Space fundamentals and
detail our prototype implementation. Next we present our evaluation
methodology and a discussion of both results and findings. Finally, we draw
the most significant conclusions and point out future research directions.

##  2 Related Work

Our work builds on related research involving virtual meetings and proxemics
applied to ubiquitous computing (ubicomp) environments. In virtual meetings,
technology plays a decisive role in providing the necessary means for people
to communicate and collaborate while not sharing the same space. Wolff et al.
[30] argued that systems that enable virtual meetings can be categorised into
audioconferencing, groupware, videoconferencing, telepresence and
collaborative mixed reality systems. Regarding videoconferencing and
telepresence, there is research addressing the interpersonal space of the
people involved in virtual meetings, by providing a broadcast of a single
person to the group. Buxton et al. [8] proposed a system where remote people
were represented by individual video and audio terminals, called HIDRA.
Morikawa et al. [21] followed the concept of the shared space and introduced
HyperMirror, a system that displays local and remote people on the same
screen. Although this approach enables communications, its focus on the
interpersonal space renders the user experience not appropriate to jointly
create content. People need to meet in a shared space to perform collaborative
work [7]. Thereby, Buxton [6] argued that virtual shared workspaces, enabled
by technology, are required to establish a proper sense of shared presence, or
telepresence.

Using a shared virtual workspace, people can meet and share the same
resources, allowing for collaboration and creation of shared content.
Following this concept, Tanner et al. [27] proposed a side-by-side approach
that exploits multiple screens. One was used for content creation and another
to display a side view of the remote user. Side-by-side interactions allow
people to communicate and transfer their focus naturally between watching and
interacting with others and the collaborative work [27]. In addition, efforts
to integrate the interpersonal space with the shared workspace, resulted in
improved work flow, enabling seamless integration of live communication with
joint collaboration. Ishii et al. [15] introduced Clearboard, a
videoconferencing electronic board that connects remote rooms to support
informal face-to-face communication, while allowing users to draw on a shared
virtual surface. Differently, Kunz et al. [18], with CollaBoard, employed a
life-sized video representation of remote participants on top of the shared
workspace.

Shared immersive virtual environments [23] provide a different experience from
”talking heads” in that people can explore a panoramic vision of the remote
location. In the Office of the future, a vision proposed by Raskar et al.
[23], participants in a virtual meeting can collaboratively manipulate 3D
objects while seeing each other as if they were in the same place, by
projecting video on the walls of each room, thereby virtually joining all
remote places into one shared workspace. Following similar principles, Benko
et al. [4] introduced MirageTable, a system that brings people together as if
they were working in the same physical space. By projecting a 3D mesh of the
remote user, captured by depth cameras, onto a table curved upwards, a local
person can interact with the virtual representation of a remote user to
perform collaborative tasks.

Beck et al, [3] presented an immersive telepresence system that allows
distributed groups of users to meet in a shared virtual 3D world. Participants
are able to meet front-to-front and explore a large 3D model. Following a
different metaphor, Cohen et al. [9] described a video-conferencing setup with
a shared visual scene to promote co-operative play with children. The authors
showed that the mirror metaphor can improve the sense of proximity between
users, making it possible for participants to interact with each other using
their personal space to mediate interactions similarly to everyday situations.

The theory of Proxemics describes what interpersonal relationships are
mediated by distance [13]. Furthermore, people adjust their spatial
relationships with other accordingly to the activity they are engaged on, be
it simple conversation or collaborative tasks. Greenberg et al. [11] argued
that proxemics can help mediate interactions in ubicomp environments.
Furthermore, they proposed that natural social behaviour carried out by people
can be transposed to ubicomp environments to deal with interactions between
people and devices, and even, by devices talking to each other.

When ubicomp systems are able to measure and track interpersonal distances,
digital devices can mediate interactions according to the theory of Proxemics.
Effectively, Kortuem et al. [17] demonstrated how mobile devices can establish
a peer-to-peer connection and support interactions between them by measuring
their spatial relationship. Proximity can also be used to exchange information
between co-located devices either automatically or by using gestures [14].
This is illustrated by the GroupTogether system, where Marquardt et al. [20]
explored the combination of proxemics with devices to support co-located
interactions.

Vogel and Balakrishnan [28] developed design principles for interactive public
displays to support the transition from implicit to explicit interaction with
both public and personal information. By segmenting the space in front of the
display, its content can change from public to private for distinct users or
the same user at distinct occasions, and different interactions become
available. Similarly, Ju et al. [16] applied implicit interactions using
proxemic distances to augmented multi-user smartboards, where users in close
personal proximity can interact using a stylus, while users at a distance are
presented with ambient content. More recently, Marquardt et al. [19] addressed
connecting and transferring information between personal and shared digital
surfaces using interactions driven by proxemics. In this environment, digital
devices are aware of the user’s situation and adapt by reacting to different
interactions according to context. Ballendat et al. [2] introduced a home
media player that exploits the proxemic knowledge of nearby people and digital
devices, including their position, identity, movement and orientation, to
mediate interactions and trigger actions.

Based on social space considerations, Edward Hall [13] encapsulated everyday
interactions in a social model that can inform the design of ubiquitous
computing systems to infer people’s actions and their desire to engage in
communication and collaboration. Indeed, recent research uses proxemics
theory, not only to infer the intentions when people want to start interacting
with others, but also to mediate interactions with physical digital objects
[20, 25, 16]. Despite the advances in both ubicomp and cooperative work, no
attempts to extend proximity-aware interactions to remote people in virtual
meeting environments, have been made so far. We strongly believe that remote
collaborative environments have much to gain by applying proxemics to mediate
interactions between remote people. By transposing the way people work in a
co-located settings to telepresence environments, the constraints imposed by
current technologies for computer supported collaborative work can be
alleviated and the sense of presence by remote participants enhanced.

##  3 Eery Space

In this section we propose an approach to bring geographically distant people
together into a common space, and to provide both devices and feedback for
participants in a virtual meeting to be able to proximally interact. We call
this concept Eery Space. Given that people are distributed across similar
rooms in different locations, Eery Space attempts to consolidate these in a
common virtual locus, while providing new opportunities for interaction and
communication between participants. In this way, people equipped with personal
handheld devices can meet, collaborate and share resources regardless of where
they are.

Instead of placing users in front of each other, as is typical of commercial
applications and other research works [3, 5], we place both remote and local
people side-by-side, similarly to Cohen et al. [9]. Unlike the common
interactions with remote people using the mirror metaphor, Eery Space provides
remote participants with a sense of being around local ones in a shared space.
This creates and reinforces the model of a shared meeting area where proxemic
interactions can take place. Moreover, each person gets assigned a definite
position and a personal locations within Eery Space. Allowing both local and
remote people to collaborate by relating to their personal spaces strengthens
the notion that everyone is treated similarly as if they were all physically
co-located.

Furthermore, Eery Space makes it possible to accommodate differently-sized
rooms. Its overall size and shape reflect the dimensions of the different
meeting rooms in use, as depicted in Figure 1. Our goal is thus to preserve
the dimensions and proportions of each participant’s position and motion. In
this way, a displacement of one meter in a room matches one meter in another
room mapped inside Eery Space, thus avoiding unrealistic movements by the
meeting participants. Nevertheless, when a room is substantially smaller than
another, people can be located out of reach of other participants. This
requires additional techniques to gather their attention in order to
collaborate, which we describe in the next section of this paper.

Figure 1: Eery Space, merging two different sized rooms into the same virtual
space. The different colours match people to their corresponding physical
room.

###  3.1 Social Bubbles

Hall’s [13] model of proxemic distances dictates that when people are close to
each other they can interact in specific ways. Within a proxemic social space,
people do interact in a formal way, typical of a professional relationship. In
contrast, the personal space is reserved for family and friends, and people
can communicate quitely and comfortably. Yet, as described by [13], these
distances are dynamic. Friendship, social custom and professional
acquaintanceship can decrease interpersonal distances [26]. We adapted these
concepts to Eery Space, using a device we call Social bubbles.

Inside Eery Space, interactions are initiated by analysing the distribution of
people within the shared virtual space. People having a closed conversation or
involved in the same task usually get closer, and, therefore, we create social
bubbles resorting to distance. People naturally create a bubble, by coming
sufficiently close to each other. Destroying bubbles is analogous to creating
them - a social bubbles ceases to exist when its participants move apart.

The intention of people to perform a collaborative task is thus implicitly
captured when they create a social bubble around them. Since we are in a
working context, people enter the others’ personal space, not because they are
either family or friends. Rather, a social bubble appears through the
intersection of the personal spaces, as depicted in Figure 2. This formulation
allows people motivated to initiate collaboration to easily create proximal
interactions adopting a distance inside their social space, without needing to
enter the others’ personal space. In our work, we considered personal space as
a circle 0.6 meter in radius. Thus two people can create a social bubble by
approaching the other within 1.2 meters .

To summarise, we define social bubbles as the virtual space arising from
intersecting personal spaces of two or more people, whereby participants can
meet, share resources and engage in close conversation.

Figure 2: Social Bubbles: (A) While distant from one another, (B) A social
bubble happens when people’s personal spaces intersect.

###  3.2 Remote Proxemics

Remote Proxemics aim to harness natural interactions that occur between co-
located people and make these available to meeting participants who are not
physically in the same room. On this way, all interactions within Eery Space
can work similarly for local and remote people. The success of our approach is
to ensure that both local and remote people are always present and positioned
side-by-side, so that participants can create social bubbles in a similar way,
regardless of whether they are or not located in the same room. Social bubbles
can include two or more users, either local or remote. When located in the
same bubble, users can naturally engage in collaborative activities.

Since Eery Space defines an environment with multiple people and devices, we
have grouped these interactions into two groups: person-to-person, for
interactions involving people and their own mobile devices; and person-to-
device, to accommodate interactions between people and shared devices, such as
wall displays or tabletops.

Figure 3: Remote Proxemics: (A) Two local people and one remote (outlined in
white) created a social bubble and are engaged in collaborative work. (B) The
remote participant, closest to the wall display, acts as the moderator,
controlling what can be shown in he shared visualization.

### Person-to-person Interactions

When people come together and create a social bubble, different tools become
available to support collaborative tasks, as person-to-person interactions.
These interactions include both the participants and their personal handheld
devices, as depicted in Figure 3(A). Since verbal communication is a key
element to the success of virtual meetings, participants can both talk to and
listen to other people inside their bubble. When people establish a social
bubble, their handheld devices automatically open a communication channel to
local and remote participants alike. This channel is closed when the bubble is
destroyed. Similarly and simultaneously, if there is a shared visualization
device, such as a wall display, the handheld devices of participants in the
same social bubble can be synchronised to the common visualisation. At this
stage, participants can engage in a collaborative session around the shared
visualization, either by discussing or by collaboratively creating content.

### Person-to-Device Interactions

The Eery Space may feature shared devices, such as wall displays and tabletops
to support shared visualization and collaborative settings. In our work, we
explored the latter kind, as shown in Figure 3(B). Due to their large
dimensions, these displays can provide a visualisation surface to serve many
people at the same time. Also, these devices do not confine people to a single
position. Users of wall displays can freely move alongside the surface to
better reach the displayed information, move forward to glimpse more details,
or move back to get an overview. These displays serve to make the information
under analysis accessible to all meeting participants. Naturally, these shared
devices should be located at the same virtual position across all remote areas
that make up the Eery Space, to ensure a consistent visualization to all
participants.

When a participant establishes a close proximity relationship with the
display, he/she becomes moderator. In Eery Space, moderators have a special
authority that allows them to control the common visualisation on all shared
displays, either local or remote, by mirroring actions performed on the
handheld device. We define moderator space as the area within a distance of
1.5 meters away from the wall display, analogously to the place normally
occupied by a person giving a talk to an audience. Furthermore, the role of
moderator can only be handed over when the person assuming this role abandons
the moderator space, leaving it available for another participant who wishes
to take over. Furthermore, when a meeting participant becomes moderator, a
channel for speech communication is opened so that they can address all
meeting’s attendees. The moderator’s speech is relayed through their handheld
device to remote participants, since local participants are within earshot.
Moderators relinquish their role when they abandon the moderator space. When
this happens, if another person is standing on that space, they become the new
moderator. Otherwise, the moderator role becomes open for other meeting
participants to take.

##  4 Prototype

We built a prototype system to prove our assumptions that remote proxemics are
possible and Eery Space is an effective approach to manage interactions
between participants as if all were in the same room. In this section, we
describe both the prototype implementation and awareness techniques to provide
appropriate feedback for interactions between participants, local and remote
alike.

We opted to develop a scenario to design and review 3D CAD models in the oil
and gas industry. Our prototype takes into account real usage scenarios to
build a virtual environment around a model of a vessel for offshore oil
production, storage and offloading.

###  4.1 System Architecture

Figure 4:  The Architecture of the Eery Space prototype.

Our prototype materialises the Eery Space. It includes an ecosystem where
multiple running modules communicate with each other using local networks and
the Internet. Since Eery Space aims at merging together multiple physical
rooms into one unique virtual space, there must be similar setup in each
physical room as displayed in Figure 4. In general, there is a software client
handling each device in Eery Space. We built this software using the cross-
platform engine Unity3D.

As demonstrated in the Figure 4, our prototype environment follows the client-
server network model. Each client has a local version of the data model, a
representation of what is happening in Eery Space, which is synchronized using
messages passed through a root server. TThe different components communicate
with the server via RPCs using UDP. Since our solution aims to join the
different rooms in a single virtual space, each component of the environment
is aware of its physical location.

###  4.2 Tracking People

Our user tracker locates people indoors non-intrusively using computer vision.
This is a standalone module serving the users’ positioning data, gathered from
multiple Microsoft Kinect depth cameras, using a scalable architecture of add-
on camera modules that can be plugged at run-time. This ability to support
multiple cameras can deal with multiple user body occlusions that naturally
occur when people stand front of others in a cameras’ field of view. The
Microsoft Kinect camera can track users between 0.8 to 4 meters. When multiple
depth cameras are placed in a circular distribution, the tracked area can have
upto 6.4 meters in diameter.

Each instance of the tracker, residing in its corresponding room, includes a
main application and a sensor client per camera. These clients collect depth
camera data and send them to the main application. The main application
receives data from sensor clients in the same physical room and, by knowing
the position and orientation in the physical world of each depth camera, can
keep track of the information about tracked people. A toolkit makes the merged
data available to every client connected to the Eery Space.

We developed a Graphical User Interface (GUI) approach to bind people with
their handheld devices. It displays a map with the position of currently
tracked people in the selected room, highlighting those not associated with a
device. When entering the Eery Space, participants are required to select
their representative icon on the handheld device screen before they are able
to initiate any interactions.

###  4.3 Providing Awareness

By knowing the distances between each participant, the system has all the
information needed to infer the intentions of each person. Following the rules
of design, participants are grouped into social bubbles and, when applicable,
someone is chosen as moderator. Last, the system updates the presentation in
all connected clients and applies the awareness techniques described in this
section.

While becoming and staying aware of others is something we take for granted in
everyday life, maintaining this awareness has proven to be difficult in real-
time distributed systems [12]. Previous research indicated that people can
respond socially and naturally to media elements [24]. Therefore, we allow
remote users to interact through appropriate virtual proxies. When trying to
keep people conscious of other people’s presence, an important design issue is
how to provide such information in a non-obtrusive, yet effective manner.
Following the collaborative guidelines proposed by Erickson and Kellog [10],
we used the techniques described bellow to increase visibility and awareness
of other users, namely for remote participants, either through a projected
floor, personal handheld devices or, in the current implementation, a wall
display.

Figure 5:  Awareness Techniques: (A) Circles projected on the floor depict the
location of people in the Eery Space. In this case, a remote and a local user
are establishing a social bubble. (B) Users shadows depicting two participants
on the wall display. The larger shadow indicates that the remote person has
the moderator role (green).

### Floor Circles

In the Eery Space prototype, every local and remote participant has a
representative projected circle on the room’s floor, as depicted in Figure
5(A). All circles are unique, corresponding to a single person, and are
distinguished from each other by a name (the participant identity) and the
user’s unique colour. These circles track a person’s position within Eery
Space, in order to visually and define the participant’s personal space, thus
making all people aware of the others. Thus floor circles provide the
necessary spacial information for participants to initiate and be aware of
proximity interactions.

In addition, projected circles depict a user’s proxemic zones. The inner
circle, with a radius of 0.3 meters, matches the participant’s intimate space.
The outer ring, depicts the personal space, with a radius of 0.6 meters. When
people come together to start a social bubble, the circles on the floor depict
the status of their Social Bubble, by matching the personal space’s color of
the bubble participants, while maintaining the user’s color in their intimate
space. The social bubble receives a colour which averages the color of its
members. This guarantees that the bubble color is unique and unmistakably
different from other content on the floor.

Since Eery Space merges physical rooms of different dimensions into one shared
virtual space, it may occur that some participants become out of reach of
others positioned in smaller rooms. To address this, we implemented a
technique to notify people who become out of reach. These participants are
depicted as semi-circles on the edges of the smaller room floor, showing their
direction in the virtual space. To differentiate these participants, their
intimate space is left blank (Figure 6.A). When a participant tries to
interact with another that is out of reach, a glowing path appears in the
floor of the latter’s room (Figure 6.B), indicating that someone others trying
to interact with them, but are unable to do so. They can then approach the
circle of the said person and initiate a proximal interaction.

Figure 6:  Out of reach users: (A) While out of reach, a representation of the
participant remains on the boundary of the local area. (B) Visual feedback on
the projected floor shows an interaction request to the out of reach
participant.

### Intimate Space

We designed Eery Space keeping each person’s personal locus in mind. Every
user has their own space assured, even if they are not in the same physical
room as the others. To prevent users from invading another user’s intimate
space, we provide haptic feedback by vibrating their handheld device, when
this happens. Participants can then quietly adjust their positions without
interrupting the main meeting, since this technique does not use audio or
visual cues. This way, each user’s intimate space is preserved and made
visible at all time to all participants, so that they can interact with it.

### Wall Shadows

Additionally, and since we included large wall displays in our prototype,
every person gets assigned a representative shadow on the wall display,
distinguished by a name and a unique colour, as shown in Figure 5(B),
similarly to the work of Apperley et al. [1]. This allows for a quick
realization of all meeting’s participants. The location of the shadow reflects
a distance from the person to the wall to give a sense of the spacial
relationship between a person and the interactive surface. Wall shadows take
in consideration an imaginary directional light source placed at the infinity
and oriented towards the wall display, with an inclination of 45 degrees.
Thus, the nearest person to the wall display will have a shadow covering more
area than the others. A larger shadow also makes it clear who is the
moderator. Furthermore, each user sees a coloured aura around their shadow.
Similarly to the circles on the floor, when two or more people shadows share
the same aura, this means they are in the same social bubble and can thus
initiate collaborative tasks.

##  5 Evaluation

To assess the effectiveness of Remote Proxemics, we conducted an user
evaluation to assess the proximity-aware interactions within the Eery Space,
both with local and with remote people. This procedure aimed to determine
whether our approach was successful in bringing remote people together in the
same virtual space while, maintaining their presence noticeable to both local
and remote participants. We also evaluated the role of the moderator, who
grabs control of the wall display using a person-to-device interaction method.

###  5.1 Methodology

In our experiment, test participants were accompanied by two people, one local
and one remote, split across two rooms. Subjects were invited into the room
with the main setup, while the remote user was in a room equipped with a
”light” version with one Microsoft Kinect camera, one display showing the
floor projection and a smartphone. Each participant received a smartphone
running the handheld device client.This evaluation took place in the context
of virtual meetings. Therefore audio communication channels were maintained
between the subject and the remote person in all social bubbles’ interactions.
The average duration for each session with users was about thirty-five minutes
and was divided into three stages:

1\. Introduction (10 minutes): At the start, each new subject was greeted with
an explanation of the objective for this evaluation session and the Eery
Space, followed by a demonstration of the prototype’s features, and a
description of the awareness techniques. They were also made aware that they
would be interacting with another (remote) person.

2\. Evaluation Tasks (20 minutes): The subject was accompanied by both the
local and the remote experienced participant, thus receiving verbal commands
for the tasks he/she should perform, which are described next.

3\. Filling in the questionnaire (5 minutes): Upon completion of the tasks,
each subject was asked to fill out a questionnaire, not only to define the
user profile, but also to gain an appreciation of the various components of
our approach.

###  5.2 Performed Tasks

This evaluation was mainly designed to check if there is any significant
difference between local and remote interactions. Therefore, participants were
asked to perform a collaborative task with both local and remote people. Also,
to verify if subjects react to the presence of other remote people, their
intimate space was purposely invaded to assess their reaction. Below, we
describe the set of tasks performed:

1\. Interaction with the wall screen display: Since navigation in the virtual
environment is beyond the context of this evaluation, a button was placed on
the prototype that redirects the virtual camera on the smartphone to a
specific point of interest in the model. Thus, the task here was to
synchronize the visualization on the wall display with the smartphone, by
assuming the role of moderator.

2\. Interaction with the local person: Participants were asked to jointly
create a collaborative sketch. For this, he had to physically move to
establish a social bubble with the local person and wait for instructions.
Then, the local person would draw a square around the point of interest, as
depicted in Figure 7, and ask the subject to draw a circle inside it.

Figure 7:  Evaluation: (A) Test user interacting with the local participant
during the an evaluation session. (B) Handheld Client. User engaged in a
sketch collaborative task.

3\. Interaction with the remote person: This task is very similar to the
previous, but it was performed with the remote person. After establishing a
social bubble with the remote person, the remote person would instruct the
subject, through the proxemics-enabled communication in the handheld device,
to draw a cross inside a circle he had drawn. At the same time, he would
intentionally step inside the subject’s intimate space to arouse some
reaction.

4\. Intimate space pursue: For this task, the test user was instructed to
watch the action performed by the remote person as moderator. At this stage, a
computer controlled remote user started pursuing the subject, continuously
attempting to invade his intimate space.

5\. Pathway through remote participants: This task was designed to realise if
subjects had realised the concepts exposed in this evaluation. The user was
instructed to move to a target location while considering the presence of four
computer generated remote participants. At no point in this evaluation
participants were told that they should not step over other people’s space.

###  5.3 Participants

The participants in this evaluation were invited randomly and were mainly
students attending our educational institution. Thereby, the set of test users
was comprised of 12 participants, one of which was female, and all with a
college degree. In regard to their age, all test subjects were between 18
years old and 24, except one that was between 35 and 55 years old. All
reported having experience using smartphones in a daily base. Every test user
had no previous experience with work in question.

###  5.4 Results and Discussion

In this section, we present an analysis of the data obtained from the
evaluation of our solution. The data gathered of the user’s preferences were
obtained from a Likert scale with 6 values. Also, we also present data from
direct observation in this analysis. Since the main objective of this
evaluation was to demonstrate the feasibility of remote proxemics by
maintaining an adequate level of awareness of the people that are remote, the
analysis of the results is divided into Proxemics Analysis and Awareness
Analysis. Table 1 summarizes the responses obtained from the questionnaire
regarding those aspects.

Question: It was easy to… | Median (IQR)
---|---
1. …control what is shown on the wall display. | 6 (1.25)
2. …start an interaction with a local participant. | 6 (0)
3. …start an interaction with a remote participant. | 6 (1)
4. …see who is present at the meeting. | 6 (0)
5. …see where each participant is. | 6 (1.25)
6. …see who is controlling the wall display. | 6 (0.25)
7. …see that I’m interacting with other people. | 6 (0.25)
8. …see which participant I’m interaction with. | 6 (1)
9. …see that I’m in the intimate space of another local participant. | 6 (0)
10. …see that I’m in the intimate space of another remote participant. | 6 (0)

Table 1: Questionnaire’s results (median and interquartile range): proxemics
overview (questions 1 to 3) and awareness overview (questions 4 to 10).

### Proxemics Analysis

Participants’ preferences regarding proxemics interactions are related to
their easiness to perform proximal interactions with both local and remote
people, and also the ability to interact with the wall display. The latter,
poses a conscious decision to become the moderator of the virtual meeting. The
presented data suggests that it was easy to assume the role of moderator.
According to the Wilcoxon Signed Ranks test, applied to the first and second
questions (Z = -1.890, p = 0.059), there are no statistically significant
differences between starting a interaction with the other participants,
despite their local or remote statuses. This leads us to conclude that, in
Eery Space, interacting with remote people is no different than local
interactions. This result is encouraging as it shows that remote proxemics are
in fact possible and do not add obstacles in the course of virtual meetings.
In the evaluation sessions, participants did not demonstrate any difficulty in
repositioning themselves to establish social bubbles in the collaborative
tasks, although three users took a little while (around five seconds) to
remember how to become the moderator while in the first task.

### Awareness Analysis

For awareness, the data shows that people in the virtual meeting can relate to
the presence of remote participants. User’s preferences suggests that, despite
exhibiting a slight dispersed data (question 5), the absolute location of
remote people is easily perceived. We can safely deduce that participants in
the virtual meeting are always aware of the people involved. One of the
requirements of our approach is the preservation of the intimate space of
remote people. This design principle is required to impose their presence,
while fostering remote interactions by establishing social bubbles. The
Wilcoxon Signed Ranks test applied to the questions 6 and 7 (Z = 0.000, p =
1.000) shows no statistically significant difference between local and remote
people, suggesting that test users were aware when their intimate space
intercepted others’. Curiously, while performing the collaborative task, three
test users made a point of informing the remote participant of his
infringement on their personal space during the smartphone-enabled
conversation, before readjusting their position. Every subject changed their
positions, during the intimate space invasion task, responding to the haptic
feedback from the handheld device. Despite that, four users first complained
that the remote participant was invading their intimate space, and only then
proceeded to readjust their positions. Regarding the final task (the pathway
between remote participants) only one user did not take into account the
presence of the remote participants and walked right thought them, while the
remainder eleven accepted the presence of remote people and walked
accordingly, dodging the floor circles while walking to the destination. It is
then safe to say that, in general, participants were aware of the presence of
the remote participant and reacted accordingly. Nevertheless, one of the test
subjects expressed the need to be aware of the others orientation in the
meeting.

##  6 Conclusions and Future Work

Virtual meetings play an important role in bringing geographically separated
people together, and are broadly used in business and engineering settings
where experts around the world engage in collaborative tasks. While current
videoconference and telepresence solutions do enable verbal and visual
communication between all participants, other forms of non verbal
communication, namely social interactions through proxemics, have not been
explored to their full potential.

We have introduced Remote Proxemics, which brings social interactions to
virtual meetings, and explores interactions between local and remote people as
if they were in the same space. To this end, we created Eery Space, a shared
virtual locus where people can meet and interact with each other using Remote
Proxemics. We developed a prototype to explore both people-to-people and
people-to-device interactions and study techniques for providing the
appropriate awareness.Indeed, these awareness techniques render Remote
Proxemics possible, since they highlight the presence of remote people. Using
a projected floor and personal handheld devices, people can see others’
representations and quickly realise their location and status on the virtual
meeting. Results from our evaluation show the promise of Remote Proxemics,
since we were able to achieve seamless interactions between local and remote
people. We believe that the work here described extends proxemic interactions
to augment the presence of remote users in virtual collaborative settings to
address commonly-raised concerns. Furthermore, our results apply even in the
absence of commonly explored devices such as avatars and eye contact.

We consider that it is both possible and interesting to apply our innovative
approach to additional purposes and scenarios, ranging from engineering to
architectural projects. To bind people with their personal handheld devices in
a more flexible manner, we intend to explore automatic approaches, for example
using computer vision, as suggested by Wilson et al. [29]. Also, we consider
that it would be interesting to assess whether adding support for f-formations
[20] will also enrich remote interactions in the Eery Space.

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