Hybrid City Lighting - Improving Pedestrians' Safety through Proactive Street Lighting

Abstract

Although digital revolution has pervaded almost every part of daily life, cities remained seemingly analogue and furthermore inhabitants are mostly excluded from the digital layer. By replacing timeworn light bulbs with a projector linked with an intelligent sensor array we expect to increase social interaction within open spaces by creating a more engaging way through the city and reduce the use of distracting and separating mobile devices. We propose several applications to support the weakest traffic participants– pupils–having a safe way to school and back, prevent accidents and guide pedestrians through an increasingly complex city. We want to provide a more economical, safer and smarter way to lighten up the way through future cities.

Full text

Hybrid City Lighting
Improving pedestrians’ safety through proactive street lighting
Andreas Sieß, Kathleen Hübel, Daniel Hepperle, Andreas Dronov, Christian Hufnagel, Julia Aktun, Matthias Wölfel
Faculty of Digital Media, Furtwangen University, Furtwangen, Germany
{andreas.siess, kathleen.huebel, daniel.hepperle, andreas.dronov, christian.hufnagel, julia.aktun, matthias.woelfel}@hs-furtwangen.de
Abstract — Although digital revolution has pervaded
almost every part of daily life, cities remained seemingly
analogue and furthermore inhabitants are mostly excluded
from the digital layer. By replacing timeworn light bulbs with
a projector linked with an intelligent sensor array we expect to
increase social interaction within open spaces by creating a
more engaging way through the city and reduce the use of
distracting and separating mobile devices. We propose several
applications to support the weakest traffic participants–
pupils–having a safe way to school and back, prevent accidents
and guide pedestrians through an increasingly complex city.
We want to provide a more economical, safer and smarter way
to lighten up the way through future cities.
Keywords — Smart City; Intelligent Street Light; Hybrid
Space; Pedestrian Safety
I. INTRODUCTION
The digital revolution has pervaded people’s everyday lives
and does not spare the urban landscape. With focus on present and
future developments and in the light of smart city technologies,
intelligent systems are being integrated in sectors like city’s
economy, mobility, governance, living, environment and people.
As a reaction to population growth as well as the effects of
urbanization, cities are committed to establish new information
and communication technologies. [1] Putting these complex
category groups aside, there will be an increasing need to precisely
focus on the future of city dwellers and actively integrate them into
the digital progress. Citizens are not willing to be a passive entity
anymore but want to actively use and interact with their
environment. [2] Using digital media, cities can be transformed
into living and changing organisms in order to make urban
environments a better adapted and customized space to fulfill
particular needs of each individual.
At present the majority of civic and public innovative
technologies require an ownership and understanding of complex
mobile devices as well as access to local services that might be
only accessed by particular user groups. Hence it is inevitable to
mention that the gap between those who have access and those
who have not, the so called digital divide, becomes even bigger by
the minute. In addition, mobile-communication usually excludes
others and thus only fits the respective need of a single person.
Another important focus lies on people’s need for safety [3].
Looking at present statistics dealing with numbers of pedestrian
accidents, there are clear tendencies showing a decline over the
past years [4]. Despite those positive developments, present
approaches for accident prevention seem to be exhausted. In
addition, the recent intensive use of mobile devices while walking
cannot be determined at the moment. Though first statistics
indicate that the use of those devices are a real distraction and that
their use can result in serious accidents [5].
Hence the aim of Hybrid City Lighting (HCL) is to bring
‘illumination’ to the residents, to overcome the previously
mentioned drawbacks and to create a solution that can easily be
integrated into the city, grant access for anybody independent of a
social group, grant access without any further requirements and
especially provide information wherever there is danger and
information is needed. We focus on enriching open spaces and
particularly pavements and thereby support creating a hybrid
space – a merger of common, analogue elements and virtual,
augmented content.
II. RELATED WORK
Besides this project, there are several other approaches to help
guiding people through or simply let them enjoy their augmented
urban environment. The various approaches derive from a broad
number of fields of which we can mention only a view: art [6],
digital signage [7], the car industry [8], and location based games
(including pervasive and augmented reality games [9, 10]. Each of
them shows that the notion of providing additional information,
feedback or gameplay within (future) cities could help to improve
inhabitants’ life. The Van Gogh Path by Studio Roosegarde for
instance, tries to enrich unlit streets, by implementing fluorescing
elements as a way to make people feel safer on their way home. A
more subtle way of providing information through interactive
communication was set up in Freiburg i. Br., Germany. The Säule
der Toleranz uses intelligent lighting by sending visual signals
determined by the permitted acoustic level of the crowd. [11]
Another concept describes the guidance of (pedestrian) crowds
through an urban street network via subconscious incentives
within the colour temperature of street lighting. [12]
The Canadian Designers Quartier des Spectacles created a
prototypic installation in which they installed projectors above a
junction in Montreal. They implement their system in different
ways: on the one hand, they use it to communicate guidance
recommendations for pedestrians and on the other hand, it is used
for advertising and event promotion. [13] The targeted advertising
industry certainly took some first steps: Interactive “Digital
Signage” respectively “Digital out of Home” attempts are arising
at a high rate. They are exclusively used to deliver advertorial
messages over a digital layer from which targeted information can
be retrieved in retail stores and other urban spaces [7]. However,
the mentioned proliferation of those screens implicates either an
information overload or a masking.
Taking a look at the car industries, which always have been
interested in fostering innovation and safety, Mercedes took a first
step towards enhancing cities’ digital based information by
coming up with the so-called “shared space in tomorrow’s world”
[8] in which they try to increase pedestrians’ safety by letting their
cars communicate via signals. In detail, they assembled a projector
within the car’s radiator grill which is able to help people cross the
street by projecting a crosswalk in front of them.
2015 International Conference on Cyberworlds
978-1-4673-9403-1/15 $31.00 © 2015 IEEE
DOI 10.1109/CW.2015.51
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2015 International Conference on Cyberworlds
978-1-4673-9403-1/15 $31.00 © 2015 IEEE
DOI 10.1109/CW.2015.51
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III. STREET AS A DISPLAY
Our concept tries to pick up on existing infrastructure that can
be found in almost every town: The street lights. To ensure that the
HCL does not require too many resources and efforts, only the
head (containing the lamp itself, the reflector and electronics) of
each lamppost has to be replaced. Although each head is an
independent system that could operate on its own, the real benefit
can be gained by using an array of many heads that communicate
which each other. In times of big data and the individual
requirement of privacy, our concept of HCL tries to contribute to
the principle of only sharing the bare minimum of data necessary:
Each head contains a simple network router that can only
communicate with other heads in the near field neighborhood via
wireless technology.
By using the street as a display, we believe that this concept
offers benefits in a social and technical way: At the moment every
user requires a device (e.g. smartphone, smart glasses, augment-
tation devices) to enter a city’s digital layer. Though considering
user groups like tourists, children or elderly who are not able to
connect with local services, entrance barriers to important
information are often too high and unequally distributed. In our
concept the use of a device to interact with the applications is not
needed. We hope that our solution fosters the city as a social hub
where real face-to-face communication is not prevented through
personal devices. Technically the main advantage of the projection
over displays integrated in the street’s surface is its insensibility
against dirt or snow (although these displays can be an alternative,
especially in situations where projections are not possible).
Augmented applications–as an alternative–are not able to provide
highly accurate mappings, they might overlap relevant information
and can only be used by a single person.
IV. SAFE WAY TO SCHOOL
Traffic safety and the safeness of pedestrians is an important
topic that deserves constant attention: Children between the age of
6 and 15, especially on their way to school and back (between 7-8
am, 1-2 and 4-5 pm), are exposed to great risks and become victims
of traffic accidents [14]. Considering these time peaks of the
statistics the following applications will particularly be necessary
during the dark seasons when traffic creates increased risks of not
being seen [15]. There are many reasons causing these dramatic
data like speeding and incautious motorists, missing assistance for
crossing streets or insufficient lighting [16]. Other main factors
though also are inexperienced and incautious children. For
example, young children before the age of 10, often are unable to
recognize possible danger, are not able to evaluate velocity and
distances and often are not concentrated and easily distracted by
other interests [16] or by playing with their smartphones.
To address these issues and lower the risk for pupils, we are
combining the technology of the HCL and selected game theories.
Basic principles of game design and slight adaptations in order to
the open space issue will serve as groundwork for the following
applications. Salen and Zimmerman [17] propose six simple
hypotheses that are crucial to understand why people play and why
certain games are so loved. To summarize: A game has to be
simple, unique and elegant in its representation, social as well as
fun and cool.
Implementing easy and well-known analog or digital games,
that are interactive and entertaining, we can identify with those
facts. Making use of depth-sensor techniques that is able to track
one or more persons, we also provide the possibility to connect
single players to cooperate in team or perhaps as competitors.
Therefore we want to support social interaction and team spirit.
Fig. 1. Soccer game projected by HCL
Considering sudden dangerous situation in traffic, we are
eager to provide games that in contrast to well-known video games
are less involving and absorbing but still are attracting enough to
compete with smartphone content and games or other distractions.
With our approach we are able to consider the children's surround-
dings and include and react to it which mobile games cannot. We
are able to provide a targeted and also easy way to shift the focus
from the pavement to possible dangers from other traffic partici-
pants. With the help of playfully implemented guidance systems
and by using simple but engaging game components, children are
guided to turn their attention towards the pavement instead of other
distracting stimuli. Our main concern though is to easily gain back
the awareness of surrounding danger zones. In addition by offering
interesting pavement activities, we want to prevent children from
taking more dangerous routes or shortcuts.
A. CHILD SUPPORTING PAVEMENT GAMES
Due to the above mentioned high level of accidents of children
on their way to school and back as well as their unincisive
awareness of dangerous traffic situations, we propose two
pavement games. They safely lead the way in an entertaining
manner and bring back attention to risky traffic situations.
Soccer: The first game, Figure 1, is inspired by a casual soccer
game. The HCL projects a soccer court on the pavement as well as
a ball. The sensor detect one or several children to assign a ball to
each of them. The ball virtually rolls in front of the tracked person
and can be kicked in walking direction. The speed as well as the
direction of those moves are constrained to prevent children from
running too far and onto the street while following the expected
direction of the ball. Therefore the football bounces off set
sidelines as well as other balls and can only be kicked a limited
distance. The game and thus the focus on the pavement ends with
the scoring of a virtual goal before crossing a street.
Footprints: The second game is a less complex game and very
suitable for an implementation in front of traffic light transitions
where children have to be very attentive. The HCL projects
coloured footprints leading the way to school or home. Children
are supposed to concentrate on them and will receive feedback like
a water splash or a small explosion of colour when stepping onto
the footprints. Hence we are providing a fun and interactive path
that strictly ends at the traffic lights. Red footprint will signalize
where to stop and where the game will continue. They will change
to green simultaneously with the traffic light.
B. FLOOR IS LAVA – TRAFFIC LIGHT CROSSING
“The Floor is Lava” originally is a real-life game mostly
played by children and is also adapted as a computer game [18].
The game’s goal is to prevent the participants from touching the
floor. Instead, they have to move through the respective
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playground jumping from one object (e.g. furniture) to another, in
order to avoid stepping into the imaginary lava. Supporting
children to safely cross the street, this concept can be adapted
directly as they are familiar to the structure of the game. Based on
this, they do not need to solely focus on playing the game, but on
crossing the street. Hereby, a modification of the game “the floor
is lava” (referenced to in several TV-Series like The Simpsons,
Family Guy or Adventure Time) sets a foundation for this
particular approach. As demonstrated in Figure 2 our concept is
separated into 2 different states:
State 1: Depth sensors determine if someone wants to cross the
street. Depending on the outcome, there are two possible
scenarios: Scenario 1: Nobody is waiting: The HCL advises the
traffic light not to turn red. Scenario 2: Adults and children are
about to cross the street: The HCL casts a countdown on the floor
from which they can tell when the traffic light will turn green.
Fig. 2. Lava is coming / Lava is here
State 2: The lava is projected and the pedestrian light turns
green: 1) Progress bar and countdown move their position to
inform the drivers after what time the traffic light will turn green
for them again. 2) It projects a safety border to let the children
know the furthest position to the left and the right they can go. 3)
The projector casts stones on street and pavement so that pupils
are able to step on to cross the street. The stones will disappear in
a linear transition until five seconds before the traffic light will turn
green for the cars again.
V. GENERAL SAFETY
Besides our previously introduced child-safety use cases, we
developed two more application that do not superficially assist
children but adults as well. For those concepts, we are making use
of the opportunity that the light’s different angle and intelligent
sensors are raising a new level of information. Hence the
applications are able to support drivers and pedestrians by pointing
out danger zones throughout future cities.
A. CAR-WARNING SYSTEM
The main advantage of having a depth sensors implemented in
the HCL is, that we are able to detect pedestrians or even animals
still hidden behind view-blocking obstacles which due to the
viewing angle cannot be seen by car sensors or the driver. When
the system detects a person that is about to run across or onto the
street, it projects noticeable concentrical circles next to persons’
location so that oncoming cars are being warned of the imminent
danger at an early stage (Figure 3).
In order to properly evaluate the situation, the system needs
more information than peoples’ mobile devices can provide. This
can be done by calculating the depth sensor’s data in conjunction
with the values received from the infrared sensor. Thereby, the
infrared sensor determines whether the heat signatures are
equivalent to those of humans. The light needs to know the
person’s movement speed and - direction which can be calculated
by using the direction and movement vector returned by the depth
sensor. In addition, the light needs to calculate whether the driver
is able to see the person or not. Therefore, the vision cone of the
driver is calculated and applied to the environment. The warning
sign will appear gradually and is more luminescent depending on
how acute the danger is. In urgent cases, the projection will start
blinking. If the pedestrian is clearly visible again, or does not move
from the spot, the mark will fade out.
Fig. 3. Car-Warn ing Syst em
B. CLEAR ICE DETECTOR
The following concept concerning the general safety is a
mechanism to detect slippery clear ice areas on pavements or roads
and therefore prevents accidents by making the crowd aware of
any hidden and unpredictable risks.
Fig. 4. Clear ice detection
The light sensor array scans the condition of the concrete and
identifies the present H₂O amount and consistency. The detection
of the ice is based on a linearly-polarized radiation beam of the
integrated IR sensor [19] that is able to detect environmental
changes. Therefore surrounding characteristics determine the
content of the display. As demonstrated in Figure 4, pedestrians
and drivers will see virtual snowflakes instantly displayed on
unsafe areas so that traffic- and rear-end collisions, slipping and
falling can effectively be prevented. In that case, no additional road
signs, warning cones or informing video clips are required as the
information is changing in real time based on the environmental
properties. Because of the relatively longer response time of car
drivers they need to be warned well in advance. The connection of
our lamps supports this issue by reporting icy areas at an earlier
stage.
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VI. EVALUATION
Due to the rather complex approach of this concept a
quantitative analysis did not seem expedient. To evaluate the
hypotheses, three standardized face-to-face interviews (16
questions in total) were held with experts from different fields:
Paola Belloni, professor of lighttechnics and lightplanning;
graduate engineer (Dipl. Ing.) Steffen Köhler, distribution head of
Philips Lighting in Baden (Germany); graduate engineer (Dipl.
Ing.) Simon Sieß, architect and urban planner.
A broad consensus emerged in terms of security: all experts
share the opinion that security will be a hotspot in future cities.
Furthermore Köhler mentioned that in terms of safety – especially
for children – the projected budget is often not as tight as usual.
Sieß as well as Belloni are confident that the games will be a
welcome diversion for children on their way to school. All experts
believe that the ingame boundaries will lead to an increasing
presence on the sidewalk and can therefore contribute to a
significant decline of accidents by inattentive children.
VII. OUTLOOK AND CONCLUSION
The paper has presented a new attempt to enrich the idea of a
smart city. Today's smart city approaches mainly focus on superior
global issues. In those cases the ‘smartness’ of the city stays widely
hidden from the citizens and are, if at all, only accessible by
personal mobile devices. We aimed, instead, to make features of
the smart city directly and easily accessible. Therefore we
developed the concept of Hybrid City Lighting that not only can
be integrated into existing infrastructures but also projects equally
accessible information to support security and guidance. It offers
several child supporting pavement- and road crossing games as
well as general safety applications that will help make the streets
a safer place.
The HCL is also scalable in many ways and therefore offers
additional prospects that we want to introduce briefly for future
research. The street light itself can be integrated in many other
open spaces like plazas, park areas or parking lots where new
concepts like art visualizations or more complex games can enrich
the open social life of the city. Having designed a modular
construction of the lamps’ head, one will be able to attach
additional tools like a mirror system that will enable the lamp to
project content in every angle and for instance can be used for
public screening and provides an alternative to present urban
displays and projects information as well as advertisements to any
surfaces and wherever and whenever it is needed.
To also question the status quo, our concept still propose some
questions which are not yet fully answered and which have to be
taken into further consideration: Using today’s technologies and
considering the fact that artificial light will not be brighter as
sunlight, projections might not be seen as clearly during daylight
so that up to now we are concentrating on the dark seasons and
times of the day. Furthermore the emittance of light into the night
sky is considered problematic. So far it is not yet foreseeable in
which way the HCL contributes to this environmental impact.
However the HCL is also able to distribute the light in a more
targeted way. Our approach, seen as emitting more light at first
sight, might indeed be able to reduce unnecessary emittance
without the need of adequate street lighting. Also the risk of arising
occlusions through bigger objects or shadows has not been
elaborated.
Not clearly being able to prove the effectiveness of our
accident reducing concepts at the moment it will be necessary to
initiate further steps and carry out a study to provide representative
data. However, work by Swenson and Siegel [20] give hope that
our approach can be used to good effect. They demonstrated that
by overlaying digital content to the environment, in their cases
stairs, can result in a positive behavior change: Stair usage, in
comparison to lift usage, in an office setting has improved by
adding interactive components to motivate physical activity.
Besides those promising facts the main aim of this paper primarily
remains to emphasize the need to provide smart systems to make
cities a safer place, demonstrate innovative ideas and inspire
further discussion about the topic of smart cities and use of open
spaces.
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