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Surround-Screen Mobile based Projection: Design and Implementation of Mobile Cave Virtual Reality

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Surround-Screen Mobile based Projection: Design and Implementation of Mobile Cave Virtual Reality

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Virtual Reality (VR) is the employment of computer devices to simulate real or imaginary environments. Conventional user interfaces stresses the usage of screen displays to interact with the developed environment. The prospect of VR enables the user to be virtually inside the environment. CAVE is one kind of room-shaped VR technology that displays the environment on its walls. We observe some common limitations in the existing CAVE technology, such as fixed space requirements and the difficulty in moving it. In the current work, we present a novel mobile-CAVE system that uses light-weighted materials and portable powered devices. It solves the limitation of re-using the allocated space by packing it and the ability to move it easily. We have assessed our technology by performing usability analysis, power consumption, and mobility experimental study. The profound experiments demonstrated the efficiency of the proposed technology in comparison with former CAVE system.
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1
Surround-Screen Mobile based Projection:
Design and Implementation of Mobile Cave
Virtual Reality
Abdel Ghani Karkar, Member, IEEE, Muhammad E. H. Chowdhury, Member, IEEE, and Naveed Nawaz
Abstract—Virtual Reality (VR) is the employment of computer devices to simulate real or imaginary environments. Conventional user
interfaces stresses the usage of screen displays to interact with the developed environment. The prospect of VR enables the user to be
virtually inside the environment. CAVE is one kind of room-shaped VR technology that displays the environment on its walls. We
observe some common limitations in the existing CAVE technology, such as fixed space requirements and the difficulty in moving it. In
the current work, we present a novel mobile-CAVE system that uses light-weighted materials and portable powered devices. It solves
the limitation of re-using the allocated space by packing it and the ability to move it easily. We have assessed our technology by
performing usability analysis, power consumption, and mobility experimental study. The profound experiments demonstrated the
efficiency of the proposed technology in comparison with former CAVE system.
Index Terms—Virtual Reality, CAVE, Sustainable Development, Projection Paradigms, Mobile technology
F
1 INTRODUCTION
CAVE is an acronym of cave automatic virtual reality (VR). It
is an immersive technology that uses a number of pointing
projectors [1] or flat displays positioned [2] between three to six
cubical room-sized space. The CAVE was invented by Cruz-Neira
et al. [1] in 1992. The wall graphical presentation must be with
high-resolution due to the close viewing range which needs small
pixels to possess the imagination of reality. Diverse technologies
have been proposed to promote CAVE [3], [4]. However, some
popular limitations in existing CAVE systems have not been
addressed yet:
1) Space Allocation: CAVE requires adequate space for its
materials. The space allocation of CAVE varies according
to its model. Allocated space might be permanent.
2) Mobility: The setup of the CAVE in particular space is
considered nearly constant. It is not easy to move the
CAVE setup to another area.
3) Power Consumption: In order to operate the CAVE, re-
quired devices and computers with associated projectors
must be switched on. However, the environmental and
power consumption metrics are not considered.
4) Cost: The cost of the CAVE is high, including high-end
devices, projectors, walls-sized displays, and the cubical
metal room.
On the research aspect, diverse CAVE applications have been
recently published such as virtual experience for thematic tourism
[5] and vConnect Cave system [6]. Encouraged by the above pro-
posed systems, we investigate that a CAVE system that overcomes
A G Karkar and N Nawaz are with the Department of Computer Sci-
ence and Engineering, College of Engineering, Qatar University. M.
Chowdhury is with the Department of Electrical Engineering, College
of Engineering, Qatar University. E-mail:{a.karkar, nnawaz, mchowd-
hury}@qu.edu.qa
Manuscript received October 2017.
current limitations. Although, available CAVE applications can be
adopted and used in our proposed solution.
In the current work, we present a novel mobile-CAVE system.
It solves the limitation of space allocation by merely packing
CAVE equipments. It overcomes the mobility limitation by using
light-weighted materials. It reduces significantly the power con-
sumption through the employment of mobile based devices such
as mobile projectors, laptops and mobile devices. Additionally,
it decreases the cost of former CAVE technology as well as the
maintenance of corrupted materials. As shown in Figure 1, the
design is composed from: (1) mobile-projectors, (2) 3D printed
joints, (3) CAVE low-weight pillars, and (4) vellum bristol paper.
We have compared the usability and the power consumption of
our proposed mobile-CAVE with the former CAVE [1] supplied
with three walls and one ground projection. Moreover, we have
asked our participants to try moving the mobile-CAVE to make
the setup in a new place. And also, we asked them to fill a survey
to show their satisfaction. The rest of the paper is organized
as follows: in section 2, we discuss the historical literature of
the CAVE. In section 3, we provide details about our proposed
solution. In section 4, we present and discuss experiments and
user studies. And finally, in section 5, we conclude the paper.
2 LITERATURE REVIEW
The CAVE was invented by a team of researchers at Electronic
Visualization Lab at University of Illinois’ [7]. It was created for
a challenge of making one-to-many visualization instrument that
uses large projection screens. The CAVE is generally 10 x 10
x 10 inches cubical room placed in darkened room [1]. Modern
CAVE systems can project walls using reflected mirrors placed
and adjusted between high-resolution projectors. The projection
requires specific setup to ensure more immersive environment to
avoid edges between walls [1], [8].
Input and output devices such as tactile devices, haptic, or
surrounded 3D sound have been used in the CAVE such as
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2
3D Printed Joint
Pillar Intersection
CAVE Pillars
Mobile Projector Holder
Fig. 1: The main components of the proposed mobile-CAVE. It is composed from four components: (1) CAVE low-weight pillars, (2)
3D printed joints, (3) mobile-projectors, and (4) vellum bristol papers.
Wireless Ergonomic Lightweight Device (WiELD-CAVE) [4].
Gloves also have been used to provide the ability of using
hand fingers [9]. Cabral et al. [10] examined a two-dimentional
gesture identification system that can be used in virtual reality
environment, such as the CAVE. The system does not require a
participant to wear gloves in order to interact with the virtual
environment. Nan et al. [11] designed a hand-enabled interaction
application for CAVE, called vDesign. The application enables the
user to use his hand in order to interact with objects in the virtual
environment. The experimental analysis of the proposed appli-
cation showed accurate results in contrast with traditional wand
CAVE interactions. The CAVE is used vastly in scientific research
and data visualization. For instance, Leah et al. [12] proposed an
immersive virtual reality framework for instructional materials to
efficiently combine the technology and make change for practical
learning. And, Kageyama et al. [3] developed a framework for
scientific visualization called Multiverse. It can operate in CAVE
virtual reality environment and invoke visualization programs. In
addition to that, the CAVE is used to simulate medical applications
in order to analyze advanced studies for brain tumor surgeries [13].
The CAVE is used as well for entertainment [14], edutainment
[15], and for diverse simulation purposes [16], [17].
In the other hand, researchers conducted studies to provide
standardized application-programming interface (API) to support
the development of virtual environment for CAVE, such as VR
Juggler [18] and FreeVR [19]. Collaborative CAVE support was
also also considered to enable multiple users work together [20].
Over the years, the CAVE is promoted by improving its quality
and by providing different technological hardware features [3].
Improving the quality requires scientific studies along with ex-
perimental analysis that assesses its performance and its usability.
Providing features requires feasibility study and market research in
order to identify the requirements of clients, such as organizational
or industrial needs1. Zhou et al. [21] proposed a maintenance space
evaluation method examines ergonomic aspect. The maintenance
space have been evaluated by comparing free and constraint virtual
environment. The obtained result demonstrated the efficiency of
the proposed method. The financial requirements to construct
and setup a CAVE are considerably higher than normal desktop
computers [22].
While diverse researches have been conducted, the limitations
of CAVE virtual reality system are yet not solved. In this paper,
we propose a novel mobile-CAVE system uses low-weighted
materials. It solves the limitation of space allocation, mobility,
1. VisBox Caves: http://www.visbox.com/products/cave
HDMI Connection
Network Connection
Fig. 2: Mobile-CAVE architectural model
and decreases the power-consumption. The profound experimental
studies showed the effectiveness of our CAVE.
3 MOBILE CAVE DESIGN
In this section, we present the prime components of our proposed
CAVE system. First, we introduce the architectural design of the
CAVE. Second, we present the technological hardware that are
applicable. And third, we elaborate on the network communication
layer between the devices, such as laptop or mobile smart devices.
3.1 Architectural Design
In order to build effortless mobile-CAVE, we designed its pillars
with light-weighted metal poles, see Figure 1. These poles can
be easily attached and detached from each other according to
the desired size. The length of the three connected poles is three
meters. The joints of pillars are 3D printed using Acrylonitrille-
Butadiene-styrene (ABS) polymers [23]. Screws are not required
to make the setup. We designed holders to put mobile-based
projectors on the top of the mobile-CAVE. Digital devices, such as
laptops or smart phones, can be placed next to the mobile-CAVE.
Figure 2 shows the architectural model of the mobile-CAVE.
3.2 Hardware Deployment and Connectivity
Our CAVE is designed to operate with mobile projectors. Thus,
projectors according to their specifications can be connected with
wires, such as high-definition multimedia interface (HDMI) [24],
or wirelessly with WiFi connection. The communication between
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3
Fig. 3: A participant using the Mobile CAVE
devices is central [25]. The main hosting device is responsible
about establishing the connection. The hosting device can be
also configured to connect external devices. This is useful to
supply proposed system with collaborative mobile-CAVE virtual
environments.
3.3 Projection Setup
The setup of projectors is done manually by rotating projectors
in their holders. An optimal picture is obtained when all displays
have wide view with no splitting corners. The projection on the
wall depends on the mobile-projector model. Thus, the projection
alignment [26], [27] may differ according to the projector model.
4 METHODS AND EXPERIMENTS
In order to quantitatively assess the different CAVE technologies,
we developed a driving simulation game in Unity 3D [28]. The
architecture of the game is client-server architecture. The server
is the main machine that is responsible about building the virtual
world, computing required paths, and synchronizing elements
on connected clients. For the movement tracking, we employed
existing marker tracking system in order to update the virtual
environment. It uses infrared cameras to track attached light
sources. For the 3D view, we employed anaglyphic view to
simulate the 3D scenes. We run the simulation in standard CAVE
and the proposed mobile-CAVE. We used different projection
modes to assess the different qualities of the projection. Figure 3
shows a sample participant using the mobile-CAVE.
Heart Rate Variability (HRV) was used to gauge the physiological
state of participants in the quantitative evaluation of the CAVE
performance. To measure HRV, portable wireless B-Alert x10
(BIOPAC Systems, Inc.) Electrocardiogram (ECG) system was
used with two Ag/AgCl electrodes attached to a participants
chest. Following the recommendation of the supplier, the points
of attachment were (i) under the right collarbone, and (ii) under
lowest left rib bone of the participant. ECG signal was band passed
through a filter (0.05-100 Hz) digitized at a sampling frequency of
1000 Hz with 12-bit resolution. Data were stored on the hard disk
of an Intel Core i7 Personal Computer for off line analysis. ECG
signal was recorded using the B-Alert Pro software accompanied
with the B-Alert x10 system2.
The engagement-HRV analysis for a given period was accom-
plished using Kubios HRV [29]. And the obtained sequence of
beat-to-beat (RR) intervals were manually examined and edited
for movement artifacts. For the time-domain analysis, the most
evident time-domain measure is the mean value of RR intervals
(RR) and corresponding mean Heart Rate (HR), which are applied
straight to the series of successive RR interval values. The
standard deviation of RR intervals (SDN N ) is defined as
SDNN =v
u
u
t
1
N1
N
X
j=1
(RRjRR)2(1)
where RRj denotes the value of jth RR interval and Nis the
total number of successive intervals. The SDN N reflects the
overall variation within the RR interval series.
In the frequency-domain analysis, a power spectrum density
(PSD) estimate is calculated for the RR interval series. The regular
PSD estimators implicitly assume equidistant sampling and, thus,
the RR interval series is converted to equidistantly sampled time
series sampled at four samples/sec by cubic spline interpolation
methods prior to PSD estimation using Kubios HRV software.
In HRV analysis, the PSD estimation is generally carried out
using either Fast Fourier Transform (FFT) based methods [30]
or parametric autoregressive (AR) modeling based methods [31].
The advantage of FFT based methods is the simplicity of im-
plementation, while the AR spectrum yields improved resolution
especially for short samples. In this work, the HRV spectrum was
calculated with the AR method (model order was 16) without
spectrum factorization. The frequency-domain measures extracted
from the PSD estimate for each frequency band include absolute
and relative powers of VLF, LF, and HF bands, LF and HF
band powers in normalized units, the LF/HF power ratio, and
peak frequencies for each band. Absolute power values for each
frequency band were obtained by simply integrating the spectrum
over the band limits.
4.1 Projection Analysis
An experiment was carried out to compare the projection on the
paper from outside and from inside of the CAVE as shown in
Figure 4. Consequently, we analyzed the projection on the paper
in different environments in order to select the optimal design of
the mobile-CAVE. We compared the different lighting conditions
and the obtained picture quality. The dimension of the projection
was configured to 60 inch and the used distance between projector
and screen was d=2 meters. In addition, we compared the obtained
pictures with different exposure values (EV) at four (EV=4), two
(EV=2), and zero (EV=0) respectively as shown in Figure 5.
The projection on the paper showed better picture quality than
the projection through the paper. This is because the projection
from inside results distortion caused by the fibers of the paper
as shown in Figure 4. In Figure 5, the three different pictures
obtained while the projection was made on the paper with different
exposure values (EV) are illustrated. In fact, a lower EV value
resulted the best quality picture.
2. B-Alert x10: http://www.advancedbrainmonitoring.com/xseries/x10/
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In-Paper Projection
On-Paper Projection
Fig. 4: Projection direction
d
EV=0
EV=2
EV=4
ISO=100
RGB=255
Fig. 5: Projection in different EV modes
4.2 Cognitive Engagement
Data were collected from male participants their average age is
34 ±4.3years. Each participant was asked to participate in two
independent trials in each CAVE setups for three minutes long. A
participant was requested to avoid speaking, avoid moving, and
to breath regularly. Ethics approval was provided by the Qatar
University Institute Review Board before the start of the study and
all participants provided their written informed consent before the
start of any measurement. We asked participants to stop at any
time during the session if they feel dizziness or uncomfortable.
Moreover, we asked participants to fill a questionnaire after they
experienced both CAVE technologies. The questionnaire includes
usability satisfaction and system responsiveness.
Figure 6 shows the sample ECG trace from subject one and
RR intervals were calculated using Kubios HRV software and the
RR series was produced by interpolation. This RR time series
was used to calculate heart rate (HR) and HRV using the same
software.
The average HR (with the standard deviation) for two indepen-
dent trials for two CAVE configurations for four different subjects
are shown in Figure 7. This clearly depicts that the inter-subject
and intra-subject variability of heart rate during different trials and
in different CAVE configurations.
The RR time series was used to calculate the PSD using the AR
method to identify the VLF, LF and HF frequency component of
the HRV. Figure 8 shows the PSD averaged over trials for sample
participants in case of mobile and standard CAVE. The summary
of the mean PSD different participants are shown in Figure 9.
The LF and HF power were expressed in absolute terms (ms2)
and in units normalized relative to total power (minus the VLF
component). It was obvious from Figure 8 (a) and (b) that the HF
power was comparable for mobile and standard CAVE however,
the LF power varies according to the subject involvement in the
experiment. This result also complies with the subjects survey
result shown in Table 1.
Figure 9 shows that LF/HF is higher for most of the subjects
but the difference in LF and HF power is not very high; however,
for subject three LF power is much higher than HF power. This is
also reflected in Figure 8 (b), which shows that HF power is same
for both the CAVE configurations but the LF power is significantly
different.
4.3 Power Consumption
We compared the power consumption of installed devices in the
standard CAVE and the mobile-CAVE. We did not consider the
power consumption of tracking cameras. This is because our
study considers the infrastructure of the CAVE. We assumed
that tracking cameras independently submit tracking data to the
main device. The standard CAVE was equipped with four Christie
DS+6K-Mirage projectors by Christie Digital3and four DELL
Precision T7600 computers provided by DELL4. In our mobile-
CAVE, we used four Sony MP-CL1A mobile laser projectors5
and four ASUS ROG GL702V VR enabled laptops supplied with
NVIDIA GTX 10706and 24GB RAM. During the operation of the
simulation, we recorded the CPU level of the main machine and
the power consumption of each CAVE system. To measure the
power consumption, we employed a custom power meter which
takes power from the main power socket and provide power to the
CAVE system. Figure 10 shows the CPU level and the power
consumption in watt (W) for the two CAVE systems for one
minute operation. Figure 11 shows the average power consumption
of the two CAVE systems. In fact, our proposed mobile-CAVE
achieved the optimal power-saving level with acceptable rendered
frame-rate synchronization. We noted that with the increase of
CPU-processing level, the power-consumption is also increased.
Consequently, the power consumption of the proposed mobile-
CAVE is approximately 324.2±4.18W while the power consump-
tion of the standard CAVE is approximately 2367.5±4.43W.
4.4 Usability and Mobility Analysis
We asked participants to fill a survey after they used the developed
simulation in the standard CAVE and the mobile-CAVE. We put an
assumption that the usage of the standard CAVE and the mobile-
CAVE must provide the same level of user interest. Later on, we
asked participants to move the mobile-CAVE and place it in dif-
ferent place. In terms of picture clarity and brightness, participants
preferred the standard CAVE because it produces clearer picture
with distinctly saturated colors. Our mobile-CAVE uses mobile
projectors, and their colors becomes soft especially if there is
background lighting in the room. In terms of mobility, participants
3. Christie Digital: www.christiedigital.com
4. DELL: www.dell.com
5. Sony Mobile Projector: www.sony.com/electronics/projector/mp-cl1a
6. ASUS STRIX VR: www.asus.com/us/Laptops/ROG-GL702VS
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5
Fig. 6: Sample ECG Trace
120
110
100
90
80
70
60
50
Trial 1 Trial 2 Trial 1 Trial 2 Trial 1 Trial 2 Trial 1 Trial 2
Subject 1 Subject 2 Subject 3 Subject 4
Heart Rate (BPM)
Standard CAVE
(a) Trials of different subjects in standard CAVE
120
110
100
90
80
70
60
50
Trial 1 Trial 2 Trial 1 Trial 2 Trial 1 Trial 2 Trial 1 Trial 2
Subject 1 Subject 2 Subject 3 Subject 4
Heart Rate (BPM)
Mobile CAVE
(b) Trials of different subjects in mobile CAVE
Fig. 7: Power spectral density of HRV averaged over trials for the
sample participants for standard CAVE and mobile CAVE.
failed to move the standard CAVE. In fact, they preferred the
mobile-CAVE as they were able to move the equipment easily
without expertise or training. This is because the mobile-CAVE is
equipped with light-weighted materials. Moreover, users preferred
in general to use the mobile-CAVE because it solves several
limitations, such as space allocation and mobility. Table 1 shows
survey results of participants.
4.5 Cost Analysis
We studied the price of different CAVE systems available in the
market. In fact, the price is affected by the provided features of
0.012
0.01
0.008
0.006
0.004
0.002
0
50
0 0.1 0.2 0.3 0.4 0.5
Power Spectral Density (s2/Hz)
Standard CAVE
Frequency (Hz)
HF
LF
VLF
Mobile CAVE
(a) Subject 1
0.012
0.01
0.008
0.006
0.004
0.002
0
50
0 0.1 0.2 0.3 0.4 0.5
Power Spectral Density (s2/Hz)
Standard CAVE
Frequency (Hz)
HF
LF
VLF
Mobile CAVE
(b) Subject 3
Fig. 8: Power spectral density of HRV averaged over trials for the
sample participants for standard CAVE and mobile CAVE.
TABLE 1: Usability Statement.
Usability Statement Average
You fairly saw high-end resolution in the mobile-
CAVE
3.93
It is easy to make the setup of the mobile-CAVE 4.31
The mobile-CAVE is not heavy 4.23
It is easy to move the mobile-CAVE 4.21
It is possible to reuse the space acquired by the
mobile-CAVE
5.00
The cost of the mobile-CAVE is affordable 5.00
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0.37
0.22
0.12 0.11
0.34
0.19 0.2
0.08
0
0.1
0.2
0.3
0.4
0.5
Subject 1 Subject 2 Subject 3 Subject 4
LF/HF
Standard CAVE
Mobile CAVE
Fig. 9: Comparison of mean LF/HF of HRV of random participants
in standard CAVE and mobile CAVE.
0
20
40
60
80
100
2350
2355
2360
2365
2370
2375
2380
020 40 60
CPU Level
Power Consumption (Watt)
Time (Seconds)
Power Consumption (Watt) CPU Level
(a) Tracing in standard CAVE
0
20
40
60
80
100
310
315
320
325
330
335
020 40 60
CPU Level
Power Consumption (Watt)
Time (Seconds)
Power Consumption (Watt) CPU Level
(b) Tracing in mobile CAVE
Fig. 10: Tracing CPU level and power consumption in standard
CAVE and mobile CAVE.
each CAVE system. The average price of the available CAVE sys-
tems is approximately 450K ±355K USD. Thus, existing CAVE
systems use high-end machines and large projectors. However, our
proposed mobile-CAVE system does not cost more than 20K USD.
This is because the system is supplied with mobile projectors and
laptop devices. In addition, the integrated walls are composed from
vellum bristol papers and does not include expensive materials.
4.6 Discussion
In our study, we discussed the efficiency of our proposed mobile-
CAVE in comparison with the standard CAVE. Based on the
2367.5
324.2
0
500
1000
1500
2000
2500
3000
Standard CAVE Mobile CAVE
Power Consumption (Watt)
Fig. 11: Average power consumption in standard CAVE and
mobile CAVE
filled surveys and the obtained assessments results, it was clearly
revealed that the effective involvement in the simulation game in
the CAVE environment could be subjective. However, the standard
CAVE produces slightly higher involvement in a cognitive task but
the result was comparable in our proposed configuration. Most
significant advantage of the mobile-CAVE is its portability and
mobility feature, which was also agreed by all the participants.
This is because it can be easily moved and benefit from its
allocated space. Thus, it enables the user to get the benefit
of CAVE technology in schools, hospitals and market places
without practically paying thousands of dollars to setup in those
premises. Moreover, the power consumption of the mobile-CAVE
is remarkably less than the standard CAVE. This is because laptop
devices and mobile projectors consume much less power than
normal PCs and normal projectors. Additionally, the employed
mobile projectors in the current prototype can project, using their
batteries, continuously for two hours if fully charged. It can be
concluded that our proposed design of mobile-CAVE system could
replace standard CAVE system.
5 CONCLUSION
The CAVE has assured to be an efficient and persuasive VR model
that expands the capability and increases the VR experience. It
fulfills the purpose of presenting large angle view, making full-
color high resolution images, and permitting multi-person to work.
The proposed mobile-CAVE solves some shortcomings of the
standard CAVE technology. These shortcomings include, cost,
mobility, re-usage of allocated space, and power consumption.
The experimental analysis results showed the usage of the standard
CAVE and our proposed one are nearly matching.
6 FUTURE WORK
Future research efforts will consider the employment of low power
consuming cameras to track the movement of the user. We have
interest in presenting stereoscopic images through 3D mobile
projection. In addition, the design and implementation of high-
speed wireless mobile-to-mobile communication is planned.
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2169-3536 (c) 2017 IEEE. Translations and content mining are permitted for academic research only. Personal use is also permitted, but republication/redistribution requires IEEE permission. See
http://www.ieee.org/publications_standards/publications/rights/index.html for more information.
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/ACCESS.2017.2772300, IEEE Access
7
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Abdel Ghani Karkar received the masters de-
gree from the University of Balamand, Lebanon.
He received his PhD degree in Computer Sci-
ence from Qatar University, Qatar. Dr. Karkar
published more than 20 articles in high im-
pact peer reviewed journals and conferences.
His research interests include multimedia sys-
tems, m-learning technologies, semantic Web,
software engineering, artificial intelligence, and
distributed systems. Dr. Karkar managed as a
Committee Member for several conferences and
chaired many sessions.
Muhammad E. H. Chowdhury received his
B.Sc. degree (1st class 1st position) with histor-
ical record marks and M.Sc. degree (1st class
2nd position) from the department of Electrical
and Electronics Engineering at the University of
Dhaka, Bangladesh and his Ph.D. degree from
the University of Nottingham, U.K., in Biomedi-
cal Instrumentation. Dr. Chowdhury is currently
working as a Lecturer at the Department of
Electrical Engineering, Qatar University, Qatar.
Prior to joining Qatar University, he worked in
universities in Bangladesh and in the UK. His current research interests
include biomedical instrumentation and signal processing, wireless body
sensors, artificial intelligence and machine learning, embedded system
design and simultaneous EEG/fMRI. In these areas, he has published
high impact peer reviewed 16 journal and 22 conference papers. Dr.
Chowdhury has been involved in several academic and government
projects, EPSRC, EPSRC-ACC, and Hermes Fellowship program of
University of Nottingham.
Naveed Nawaz received his Master degree in
electronics engineering from University of Not-
tingham, U.K. He is currently working as a faculty
in computer science and engineering in Qatar
University. He has more than 10 years of expe-
rience in university teaching and research. He
worked with Microsoft before joining academia.
His research interests include SoC architec-
tures, hardware cybersecurity flaws and embed-
ded system security.
... The necessary effort results in a relatively high price of these systems. Depending on the configuration, the estimated price for a professional CAVE system can be between 200,000 and almost 1 million USD [115]. However, costeffective variants are possible [115,36]. ...
... Depending on the configuration, the estimated price for a professional CAVE system can be between 200,000 and almost 1 million USD [115]. However, costeffective variants are possible [115,36]. interesting [91]. ...
Thesis
With this generation of devices, virtual reality (VR) has actually made it into the living rooms of end-users. These devices feature 6 degrees of freedom tracking, allowing them to move naturally in virtual worlds. However, for a natural locomotion in the virtual, one needs a corresponding free space in the real environment. The available space is often limited. Objects of daily life can quickly become obstacles for VR users if they are not cleared away. The currently available systems offer only rudimentary assistance for this problem. There is no detection of potentially dangerous objects. This thesis shows how obstacles can be detected automatically with range imaging cameras and how users can be effectively warned about them in the virtual environment. 4 visual metaphors were evaluated with the help of a user study.
... Previous developments have also focused on mobile CAVE systems in order to overcome spatial limitations. 65 Furthermore, near-eye displays, such as AR contact lenses, include the direct projection of virtual information onto the eyes, 66 thereby providing promising future applications within the field of sports. ...
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... Ürün tasarım doğrulaması, şehir planlama, maden sahaları, tarihsel mekanların üç boyutlu görüntülenmesi, tıbbi araştırma, sanal eğitim, pazarlama ve ürün tanıtım gibi cok çeşitli uygulama alanları bulunmaktadır. 4 duvar yansımalı gerçek zamanlı sanal gerçeklik sistemleri sayesinde, mühendislik tasarımlarının doğrulaması mümkün olmakta ve bu analizlerin haricinde eğitim amaçlı da sistemler kullanılabilmektedir. Havacılık ve savunma sektöründe kokpit personelinin eğitimi, maliyet açısından daha ucuz olabilmektedir. Yurt dışında CAVE teknolojileri konusunda ön plana çıkan firmalar VisBox [4] ve MechDyne [5] firmaları olup, yurt içinde infoTRON [6] firması bu konuda çalışmaktadırlar. CAVE sistemi için genellikle, 4 adet aktif stereo projektör, 4 adet ön yüzey aynası, stereo emitörler, 10 kadar stereo shutter gözlük tedarik edilerek sistemler kurulabilmektedir. ...
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... It provides visual guidance and performance feedback in real time while performing the activities. The system employs natural user interface implemented in immersive Cave Automatic Virtual Reality Environment (CAVE) with conversational communication feature [17,18]. The feature uses Automatic Speech Recognition (ASR) mechanism to respond to the user. ...
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Overweight and obesity is a situation where a person has stacked too much fat that might affect negatively his/her health. Many people skip doing exercises due to several facts related to the encouragement, health-awareness, and time ar-rangement. Diverse aerobic video games have been proposed to help users in do-ing exercises. However, we observe some limitations in existing games. For in-stance, they don’t give correct scores while wearing Arabic traditional suits, they don’t consider showing immersive realistic scenes, and they don’t stimulate users to do exercises and keeping them encouraged to play more. We propose in this paper an aerobic video game that displays real scenes of aerobic coaches and keeps the user notified about doing exercises. It is a kind of serious games that allows users to learn aerobic movements and practice with aerobic coaches. It contains several exercises in which each can be played on normal screen or in fully immersive virtual reality (VR). While the user is playing, he/she can see the playing score with the estimated amount of burned calories. It stores the time when the user plays to remind him/her about doing exercises again. The profound user studies demonstrated the usability and effectiveness of the proposed game.
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