24-01-2013, 01:00 PM
VEHICLE-TO-VEHICLE AND ROAD-SIDE SENSOR COMMUNICATION FOR ENHANCED ROAD SAFETY
[attachment=48283]
Abstract
We propose a hybrid ITS safety architecture that combines vehicle-to-vehicle communication and
vehicle-to-roadside sensor communication. Opposed to dedicated roadside units, which require major
investments for purchase, installation and maintenance, roadside wireless sensor and networking
technology represents a cost-effective solution and can leverage the deployment of the system as
a whole. Among the various services of the hybrid communication system, the paper introduces
accident prevention and post-accident investigation. We present a system and protocol architecture
with a fully distributed concept for efficient and secure storage of sensor data. For deployment, this
architecture will likely be combined with an alternative approach using dedicated road-side units as
a centralized network element for communication and data storage. For the proposed system, we
describe the main components (radio, networking and services, security). Finally, we describe our
prototype implementation and experimental testbed featuring hardware and software platforms for
vehicle on-board units and sensor nodes.
INTRODUCTION
In order to make roads safer, cleaner and smarter, sensor and communication technologies
are increasingly considered in research, standardization and development. While today’s vehicles
are already able to sense the surrounding environment, we expect that future cars will
communicate with a roadside communication infrastructure and with each other. Connected
vehicles create a fundamental building block of intelligent transport systems (ITS) and can
provide numerous application services to improve safety and comfort of driving.
Among the various wireless technologies for vehicular communication, we can identify
a clear trend n the usage of Wireless LAN adapted to vehicular conditions in Europe and
North America [1], [2], [3]. The upcoming standard IEEE 802.11p [4] as well as the frequency
band allocations in the higher 5.8 GHz band for various public safety services clearly indicate
the next step towards deployment. For vehicle-to-infrastructure communications, the system
architecture assumes access points with IEEE 802.11p network interfaces to be set up at
least in dedicated locations (such as road intersections), whereas the system is still able to
deliver information even when no access point is available within the communication range of
a vehicle. A particular technology is vehicular ad hoc networking (VANET), which enables
communication over multiple wireless hops, potentially but not necessarily including roadside
access points.
SCENARIO AND USE CASES
Roads have always been dangerous, and a lot of efforts have been undertaken to improve
their safety. Vehicles, education, road signs have been improved throughout generations.
Nevertheless, dangers remain and with the rise of computer and wireless technologies, new
solutions are available to assist the driver in hazardous situations and to decrease road dangers.
We envision that in a near future, vehicles will be equipped with wireless devices, so
that they can communicate with each other. The primary application of this technology is
to let vehicles exchange about their current context. In detail, the information exchanged
can be of two types, (i) periodic exchange of status messages among the vehicles in direct
communication range and (ii) safety messages triggered by a critical event and distributed
in a geographical region. In the same time frame of the VANET deployment, we expect
that WSN technologies would have reached the necessary maturity to be rolled out in a
large scale at an affordable cost. We foresee that WSN roadside islands will be installed
in specific dangerous locations to support drivers with current road and weather condition.
Typically, WSN technologies help where neither the vehicle’s sensors nor the driver can detect
the danger, e.g. very localized road condition, animal crossing the road out of a forest, etc.
The roadside WSN islands significantly extend the sensing range of a vehicle. Hence, either
the driver or the vehicle itself could initiate appropriate reactions according to the current
environmental conditions with the overall aim to increase the driver’s safety.
SYSTEM AND PROTOCOL ARCHITECTURE
While VANETs and WSNs have common characteristics, such as network self-organization,
they also have important differences. VANET nodes are typically equipped with relatively
powerful computing devices. Further, since VANETs node are connected to the power supply
of a car or are located at the roadside, they usually do not have constraints on energy
consumption. In contrast, sensor nodes have extremely small physical dimensions and strong
constraint in the processing and energy capabilities. VANET nodes are also highly mobile,
resulting in frequent topology changes of the network, whereas sensor nodes are assumed to be static. The different characteristics of VANETs and WSN have led to the development of
different technology components for radio, networking, middleware and applications.
Indoor Setup and Tests
The goal of the indoor tests was to observe the capability of every vehicle inside the
Geobroadcast range to receive warning signals initiated by the WSN. Three VANET nodes
run a application that displays hazard warnings to drivers via a visual HMI. Each VANET
nodes run Geocast as part of the communication protocol stack. The positions of the vehicles
are mocked by a 4th control PC, which feeds the VANET nodes with position information and
permits to reset, pause or start the experiment at every time. Because of the proximity of the
equipment, packet dropping is also emulated based on the distance between communication
nodes. In the experiment, one of the VANET nodes is connected via IEEE 802.15.4 to a
sensor note that acts as a gateway to the sensor network. If this node is in the vicinity of the
sensor network, it will receive sensor data, and forward to other VANET nodes nearby using
Geobroadcast.
SUMMARY
We presented a hybrid architecture of vehicular ad hoc networks (VANETs) and roadside
wireless sensor networks (WSN) that relies on a fully distributed approach without centralized
infrastructure elements for coordinating of communication and data storage. Among
the manifold opportunities of such a system we focus on accident prevention and postaccident
investigations. Main technology components of the architecture are (i) radio interfaces IEEE 802.11p and IEEE 802.15.4, (ii) routing protocols Geocast and tinyLUNAR, (iii) middleware
for VANETs and tinyPEDS for WSNs, and (iv) applications. The components are
well adapted to the specific requirements of VANETs and WSN, respectively.
[attachment=48283]
Abstract
We propose a hybrid ITS safety architecture that combines vehicle-to-vehicle communication and
vehicle-to-roadside sensor communication. Opposed to dedicated roadside units, which require major
investments for purchase, installation and maintenance, roadside wireless sensor and networking
technology represents a cost-effective solution and can leverage the deployment of the system as
a whole. Among the various services of the hybrid communication system, the paper introduces
accident prevention and post-accident investigation. We present a system and protocol architecture
with a fully distributed concept for efficient and secure storage of sensor data. For deployment, this
architecture will likely be combined with an alternative approach using dedicated road-side units as
a centralized network element for communication and data storage. For the proposed system, we
describe the main components (radio, networking and services, security). Finally, we describe our
prototype implementation and experimental testbed featuring hardware and software platforms for
vehicle on-board units and sensor nodes.
INTRODUCTION
In order to make roads safer, cleaner and smarter, sensor and communication technologies
are increasingly considered in research, standardization and development. While today’s vehicles
are already able to sense the surrounding environment, we expect that future cars will
communicate with a roadside communication infrastructure and with each other. Connected
vehicles create a fundamental building block of intelligent transport systems (ITS) and can
provide numerous application services to improve safety and comfort of driving.
Among the various wireless technologies for vehicular communication, we can identify
a clear trend n the usage of Wireless LAN adapted to vehicular conditions in Europe and
North America [1], [2], [3]. The upcoming standard IEEE 802.11p [4] as well as the frequency
band allocations in the higher 5.8 GHz band for various public safety services clearly indicate
the next step towards deployment. For vehicle-to-infrastructure communications, the system
architecture assumes access points with IEEE 802.11p network interfaces to be set up at
least in dedicated locations (such as road intersections), whereas the system is still able to
deliver information even when no access point is available within the communication range of
a vehicle. A particular technology is vehicular ad hoc networking (VANET), which enables
communication over multiple wireless hops, potentially but not necessarily including roadside
access points.
SCENARIO AND USE CASES
Roads have always been dangerous, and a lot of efforts have been undertaken to improve
their safety. Vehicles, education, road signs have been improved throughout generations.
Nevertheless, dangers remain and with the rise of computer and wireless technologies, new
solutions are available to assist the driver in hazardous situations and to decrease road dangers.
We envision that in a near future, vehicles will be equipped with wireless devices, so
that they can communicate with each other. The primary application of this technology is
to let vehicles exchange about their current context. In detail, the information exchanged
can be of two types, (i) periodic exchange of status messages among the vehicles in direct
communication range and (ii) safety messages triggered by a critical event and distributed
in a geographical region. In the same time frame of the VANET deployment, we expect
that WSN technologies would have reached the necessary maturity to be rolled out in a
large scale at an affordable cost. We foresee that WSN roadside islands will be installed
in specific dangerous locations to support drivers with current road and weather condition.
Typically, WSN technologies help where neither the vehicle’s sensors nor the driver can detect
the danger, e.g. very localized road condition, animal crossing the road out of a forest, etc.
The roadside WSN islands significantly extend the sensing range of a vehicle. Hence, either
the driver or the vehicle itself could initiate appropriate reactions according to the current
environmental conditions with the overall aim to increase the driver’s safety.
SYSTEM AND PROTOCOL ARCHITECTURE
While VANETs and WSNs have common characteristics, such as network self-organization,
they also have important differences. VANET nodes are typically equipped with relatively
powerful computing devices. Further, since VANETs node are connected to the power supply
of a car or are located at the roadside, they usually do not have constraints on energy
consumption. In contrast, sensor nodes have extremely small physical dimensions and strong
constraint in the processing and energy capabilities. VANET nodes are also highly mobile,
resulting in frequent topology changes of the network, whereas sensor nodes are assumed to be static. The different characteristics of VANETs and WSN have led to the development of
different technology components for radio, networking, middleware and applications.
Indoor Setup and Tests
The goal of the indoor tests was to observe the capability of every vehicle inside the
Geobroadcast range to receive warning signals initiated by the WSN. Three VANET nodes
run a application that displays hazard warnings to drivers via a visual HMI. Each VANET
nodes run Geocast as part of the communication protocol stack. The positions of the vehicles
are mocked by a 4th control PC, which feeds the VANET nodes with position information and
permits to reset, pause or start the experiment at every time. Because of the proximity of the
equipment, packet dropping is also emulated based on the distance between communication
nodes. In the experiment, one of the VANET nodes is connected via IEEE 802.15.4 to a
sensor note that acts as a gateway to the sensor network. If this node is in the vicinity of the
sensor network, it will receive sensor data, and forward to other VANET nodes nearby using
Geobroadcast.
SUMMARY
We presented a hybrid architecture of vehicular ad hoc networks (VANETs) and roadside
wireless sensor networks (WSN) that relies on a fully distributed approach without centralized
infrastructure elements for coordinating of communication and data storage. Among
the manifold opportunities of such a system we focus on accident prevention and postaccident
investigations. Main technology components of the architecture are (i) radio interfaces IEEE 802.11p and IEEE 802.15.4, (ii) routing protocols Geocast and tinyLUNAR, (iii) middleware
for VANETs and tinyPEDS for WSNs, and (iv) applications. The components are
well adapted to the specific requirements of VANETs and WSN, respectively.