This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.
In Europe there are several different projects of ooperative Vehicle Infrastructure Systems for safe driving such as the CVIS, the SAFESPOT, the COOPERS and the VANET. This paper will try to analyze the differences between them and present the benefits of each project.
Cooperative Vehicle Infrastructure Systems
CVIS technologies and applications have grown in recent years are now moving out of the lab and onto the street.
The first demonstration will show how specific types of vehicles as emergency vehicles, public transport vehicles and trucks with dangerous goods can communicate with the active roadside equipment such as lights. An emergency vehicle lights inform its approach, identified and has given the green a priority, while other road users warned of possible clashes.
A second application will show how drivers receive recommendations on the best route to their destination and estimated time of travel on alternative routes. The estimated journey time takes into account the detailed design traffic signal rather than the average traffic flow . Vehicle-infrastructure communications also allows traffic signals to be synchronized with the vehicle, sending drivers to a proposed speed to jump to the next traffic light during the green phase, leading to significant fuel savings.
The benefits of the Cooperative Vehicle Infrastructure Systems are:
-More safety when driving.
-Informational messages from a road network management center (not only).
-Best-design service to a destination.
-Other: Internet in the car, messages from users drive a car, automatic toll payment, etc.
All the vehicles and infrastructure can generate and send real-time traffic and environment information, which, when processed and delivered to drivers, will give them several needed information and will improve the efficiency mobility leads to less traffic congestion and reduce road, fuel consumption, CO 2 emissions and frustration driver.
Comperative Synthesis of CVIS, Safespot and Coopers.
The CVIS, SAFESPOT and COOPERS are designed to improve the road safety and the traffic efficiency by offering several useful information to the drivers.
Their main differences are:
CVIS: design core technologies for cooperative systems
SAFESPOT: is focused on highly critical tasks for cooperative systems
COOPERS: is using the road operators for the conception of cooperative systems.
The CVIS Project
The CVIS is responsible for the design, the development and the test of the different technologies that allow cars to communicate securely between them and between the road nodes.
Example of mobility services if vehicles, infrastructure, pedestrian,
TCC (Traffic Control Centre), CC (Content Center), SP (Service provider), TIC (Traffic Information Centre) are nodes of a wireless network
For this purpose the CVIS project uses the CALM (Communications Air-Interface Long and Medium range). The CALM concept allows the CVIS to select the most suited communication medium for the communication between the vehicles and the nodes. The CALM architecture uses V2V, V2I and cintinious Internet access using multiple radio technologies such as: the Cellular (CALM 2G/3G), Infrared light (IR), Microwave (CALM M5), IEEE 802.11 a/b/g known as Wi-Fi, IEEE 802.11p (mobile Wi-Fi), Millimeter Waves (CALM MM), Microwaves CEN DSRC. (************). Also in the future architectures such as the WiMAX will be used. All those architectures are used under the IP (Internet Protocol) layer. The most common is the IPv6 which will replace very soon the IPv4 and will provide 2128 available global addresses (instead of 232 for IPv4).
To avoid any project's faults all the technologies of the CVIS project will be tested to six different European countries such as: Italy, Germany, Netherlands, France, Sweden and UK.
The CVIS project uses 5,9 GHz wireless LAN and 3G cellular media for the communication between the nodes and the sensors.
The SAFESPOT Project
The Safespot project is an Integrated Project funded by the European Commission. The CVIS and Coopers projects are mainly focused on increasing the road's network efficiency. Both provide reliable information about raod status, road works, accidents, traffic jams, information for parking lots and alternate road suggestion for better and faster driving. Also both use long distance communication to improve the traffic control and the information reliability to every vehicle. (********)
In contrast, the Safespot project focuses on detecting dangerous situations, inform the drivers in real-time and finally increase the road safety.
Safespot project is the last for any driver to prevent any danger and keep drive in a safe area.
The SafeSpot's Architecture
All the sensor's and the warning devices architecture of the Safespot project are designed in this way in order to offer real-time information exchange for the vehicle status and the status of all the environmental conditions of the road. The communication between the infrastructure and the vehicles must remain enabled under any situations in order to offer the several information for the safe driving. The SAFESPOT project uses V2V and V2I communication methods and IEEE 802.11p technology. Examples of the SAFESPOT project is the Safe Lane Change Manoeuvres, Frontal Collision Warning, Predictive Speed Reduction, Road Condition Status information, Cooperative Situation Awareness which will be tested based on Safety Margin and Local Dynamic Map concepts. (*****************).
Safety Margin concept in SAFESPOT
THE SAFESPOT APPLICATIONS based on infrastructure.
The SAFESPOT uses five main infrastructure-based applications: the “Speed alert”,
“Hazard and incident warning”, “Road departure prevention”, “Co-operative intersection
collision prevention” and “Safety margin for assistance and emergency vehicles” which are designed to provide the most efficient information to the driver.
HAZARD AND INCIDENT WARNING
The aim of this application is to warn the drivers in case of dangerous events on the road. The selected events are the most relevant in terms of safety: accident, presence of unexpected obstacles on the road, traffic jam ahead, presence of pedestrians, presence of animals and presence of a vehicle driving in the wrong direction or making a dangerous overtaking. This application also analyses all environmental conditions that may influence the road friction or decrease the visibility of the drivers. More generally, this application aims at describing the road status and driving conditions. Based on the cooperation of vehicles and road side sensors, this application provides warnings to the drivers and feeds the SAFESPOT road side systems and vehicles with the description of new driving situations. This application is essential to enable the other applications to have latest relevant road description.
This application provides recommended speed to drivers, with different levels of intensity, on the basis of a real-time evaluation of parameters such as: the legal speed limit, the weather status, road surface conditions, topology of the road, traffic flow speed and any events like road works, traffic jam or deviations. These parameters may be static or provided by the“Hazard and Incident Warning Application”. This application was justified by the analysis of accident data, as excessive speed is an indirect cause in more than 40% of accidents on rural roads and motorways. It is also clear that infrastructure system gives more consistent recommendations than the sole interaction between vehicles, since it has an extended ‘vision' of the road status(5).Three main sub applications are foreseen for speed alert:
- Legal Speed limit: to warn driver if his speed exceed legal speed limit. Moreover this application deals with the update of legal speed limit on the map. For instance, an infrastructure manager can decide to change speed limit on a specific area, or in case of rain, the speed limit must change, according to legal aspect.
- Critical Speed limit: this sub application deals with dynamic update of speed limit according to the alerts generated by the “Hazard and Incident Warning” application.For instance, when a vehicle arrives at a road section that is subject to a traffic jam, the system will warn the driver if he does not slow down early enough.
- Excessive Speed alert: this sub application focuses on the static black spot and on the management of driver speed while approaching this black spot. For instance, when a vehicle is approaching a sharp curve or a tunnel with a speed recommendation below legal speed limit, the application manages the warning to the driver and the speed limit. The message could be sent to the driver either using a road side unit, like a VMS, or directly inside the vehicle, if it is equipped with SafeSpot compliant devices.
ROAD DEPARTURE PREVENTION
Accident analysis results published by the French road administration for year 2004 show that a large part of road fatalities implies a road departure: approximately 30% (3). “Road Departure Prevention” is an extension of the “Speed Alert” application, and is aimed at computing an accurate safe speed according to road geometry, vehicle dynamics and driver capacity.
For instance, drivers arriving at a bend with inappropriate speed, or leaving their lane due to drowsiness, lack of attention or use of alcohol or drugs, will be warned by the “Road Departure Prevention” application. Briefly, a set of admissible trajectories is defined on the basis of the local road geometry. Each time a vehicle crosses the monitored zone its position and speed are measured in real time. In case of critical trajectory a warning is given to the driver. The warning can also be extended to the surrounding vehicles and people, for instance,to the operators of an adjacent road works site.
In the design of the application itself, the main aspect to be tackled is the definition of the allowed trajectories, which in principle depend on road geometry, road friction, vehicle speed and driver skill; whereas in the overall system development the most crucial issue is the speedin detecting and giving the feedback to the driver.
COOPERATIVE INTERSECTION COLLISION PREVENTION
This application typically concerns a static black-spot for urban roads: the intersections (2). It deeply exploits real-time computation and communication through high-speed local networks. The application will calculate and predict the trajectories of the road users present in a given intersection. An intensive use of road side sensors like cameras or radars associated to the control of local traffic lights are the cornerstones of this application. Also, a full coverage of the intersection with bidirectional communications between vehicles and the infrastructure is mandatory. Based on the trajectories of vehicles and of vulnerable road users like pedestrians or bicycles, safety-critical situations will be identified and a decision will be drawn, to appropriately warn concerned actors. However, infrastructure support will broadcast information to drivers not only in specific points, but also in wider areas beyond the black-spot to implement an efficient trategy.
SAFETY MARGIN FOR ASSISTANCE AND EMERGENCY VEHICLES
It is important that assistance and emergency vehicles can pass through the road network as safely and fast as possible. This application enables assistance and emergency vehicles to have a driving priority toward other road users. By sending a warning, directly from the emergency vehicles and through road side equipment, this application provides a “greenroute” to these vehicles by urging other vehicles to give a way and by switching traffic light controllers. Thus, this application needs to cooperate with the other applications like “Cooperative Intersection Collision Prevention”, “Hazard and Incident Warning” and “Speed alert”.
Due to the need to have very high speed communications between vehicles and the infrastructure, the chosen technology introduces a limitation in the communication range. The SAFESPOT system cannot rely on a continuous coverage of the road network except for specific identified black spots. Thus, SAFESPOT assistance and emergency vehicles will ave the ability to implement the “Hazard and Incident Warning” and “Speed Alert”
applications on non covered areas, during their intervention. They are considered as mobile road side units that can be deployed in case of the occurrence of dangerous situation.
The COOPERS Project
In contrast with the CVIS and SAFESPOT projects, at the COOPERS Project all the vehicles are continuously connected between them.
COOPERS long term vision
All the vehicles exchange useful information in real-time to improve the whole driving security of the road and enable Co-operative Traffic Management. (***************).
The COOPERS Project architecture uses:
- Communication Vehicle to Infrastructure (V2I) which uses all the vehicles and their sensors to exchange traffic control measurements
- Communication Infrastructure to Vehicle (I2V) to provide to vehicles and drivers several information about safety and infrastructure in real-time, which are more reliable than those from the radio for example.
The VANET Project
The Vehicular Ad-Ioc Networks (VANETs) is a type of wireless network that allows communication between vehicles. Quite different from simple wireless networks we have for example at home, because the topology of the nodes (vehicles in this case) changing making such a challenge in network construction.
The VANET's nodes are directly connected between them, for example without relying to any dedicated infrastructure and in contrast to older vehicle networks projects. (*********). The network is designed in that way, where if a node lose his power, intermediate nodes act as routers in order to push the data communications from other nodes that are up and running.
The communication of VANET's infrastructure is either direct which means directly connection from one vehicle to another or between the vehicles and the Road Side Units (RSU's).
The Vanet project uses the following different protocols for the communication of the vehicles and the Road Side Units (RSU's), the Wireless IEEE 802.11p, the technology of 2G/3G and many times the combining the two.
There are Different types of communications:
In this case the communication is directly from one node (or vehicle road unit) network with one another at a distance of about 200 meters.
Here we have the phenomenon of sharing a message through nodes until it reaches its final destination. In other words, each node acts as a router to forward the message below.
In the figure above you see the difference in the distribution of a message between multi / single hop. There are some limitations and in hand and not how, but I will not go into much detail.
What VANET project needs to be effective
-Main instrument is the GPS to indicate at all times our position on the map.
-Sensors in your vehicle.
- System-receiving / sending messages.
-Management System (screen in the dashboard simplistic).
Alternatively, some systems allow communications between vehicles only. Where possible and road units are directly communicating with a center, where data are collected in databases to be accessible and be able to help other vehicles.
Most cars are filled with sensors for brakes, for reading the road condition and more sophisticated as for fog detection, etc. The bad news is that until now all these data are in a closed cycle, ie in the vehicle driven.
These systems seek information and other vehicles.
We drive on a motorway, before we have enough vehicles, so that we can see eg 10th vehicle ahead how it moves. If the vehicle is braking (panic braking to speak), the message from the sensors of that vehicle will be distributed to all nodes behind the partition and they will in turn further the message to other nodes. The same would occur in a collision of two cars ahead of us, who can not see. So we though 10 positions further back we will take the message of safety (emergency) so we will have a greater margin of time to watch the movements / our speed to avoid a carom ...
Put simply, these systems allow us to "see" far beyond the sight.
If there is a problem vehicle is stationary (for example, could be a turn) or a building equipped with a road unit information will be shared on the network that in such and such a location that risk. To put a bit of your imagination, not limited only there. It could be a message sent to us, the only vehicle in front at a distance of 500 meters on bad roads.
How often surprised by a vehicle suddenly jumped from a narrow or an ambulance came from nowhere. Through such a system can be informed about the arrival of an ambulance hundred meters before we close, as we have already defined the path and will share the message of vehicles (on arrival) who are on the roads will get. We also can see the screen vehicles that can not be seen visually, such as in engines that lead in parallel next to large vehicles. Here the question arises, what happens in a city with so many vehicles and messages ... the system will be crazy as we are. The answer is that there are algorithms for allocating materiality messages. That is, the significance of which has a message for updating the speed limit on roads leading to less that one ambulance.
Since we do not want to be long story short, think of where you were making a difficult position if you knew about them before you reach the point where they are.
Updated road network:
Many times we choose to go to a specific destination, but we were moving. Sometimes the GPS shows us the shortcut, but end up doing more time than if we took another route.
We drive to town, and traffic jams on a road from which we intended to go. The processing of information from the vehicles inside the bottleneck, such as minimal mobility of the vehicle, but in relation to adjacent vehicles (and could only made a temporary stop, where it would be wise to misunderstood the situation of our vehicles like a traffic jam), generate information that such and such place in traffic jams. We accept the message, and a new destination can be given to us to get more quickly to our destination.
The GPS just like we said before, just give us the shortest route to a destination. If the network VANET involved a service center can give us the fastest way and not the earliest example counting traffic lights, intersections, speed limits and other events. Such systems are CVIS, NoW and the work of MIT CarTel. The latter has a different approach to this issue. Drive from point A to C, the distance is 10 km and the time you are 15 minutes. Another driver again went from point A to point C through the B She 12 km but the time was 10 minutes (it could have come to a highway). All data such as distance, route and time (and is no congestion at peak hours and other conditions at other times) is sent to a central server which is accessible to everyone to choose the most appropriate (fastest) route.
All these should operate within the following framework:
Do not forget that it is an open network and enough to know the position we are.
As may be authorized payment of tolls or even sharing personal messages between people in different vehicles. This requires the encryption of all data.
Alternatively should operate such a system in a town with 200 nodes around a vehicle so as not to overload the network and no need to repeat the same message from dozens of vehicles and other ways of sharing messages will be applied to country roads with few cars, where there may be other vehicles at a great distance. In such cases, messages must be stored and later promoted for example.
There are dozens of things that could be mentioned, we believe that if someone is interested can find enough material.
The bottom line is that the VANET is a science in themselves to help us all by offering safer / better quality driving and road use.
And in our country are necessary if we consider the incidence of road accidents, road works, road surface damage, unexpected obstacles, traffic jams in towns and especially in Athens, etc.