Report numberRA-MOW-2010-008
TitleEnhanced traffic safety on highways thanks to ITS.
AuthorsJohan De Mol
Erik Vanhauwaert
Wim Vandenberghe
Published byPolicy Research Centre for Mobility and Public Works, track Traffic Safety 2007-2011
Number of pages140
Document languageDutch
Partner(s)Universiteit Gent
Work packageOther: Innovatie en technologie

It can be said that enhancing the safety on highways should be simpler to accomplish then on other roads, since the number of conflict points in highways is more limited then on other roads. In principle there can be no accidents with oncoming traffic, there are no crossroads, and the speed differences are limited. Controlling conflicts on highways can be well defined. In a number of cases technology can provide a supporting role. The goal of this report is to explore the possibilities of using ITS to enhance the traffic safety on highways.


The following methodology is applied: first an analysis of statistics regarding highway accidents is performed. Then it is researched which ITS applications could have a positive impact on the safety on highways. Then it is determined which of those applications has the highest impact. Then a few technical aspects are discussed, followed by an overview of the most important relevant national and international research projects. Finally a social- and technical-economical evaluation is executed, aiming to give a complete and realistic cost overview.



The analysis of accident statistics on highways is useful to interpret traffic safety and to evaluate the most efficient IST techniques. In 2007, accidents on highways were responsible for 14% of the total number of fatal traffic victims, and 17% of the total severely wounded. These numbers indicate that the highway, despite the limited number of conflict points, is responsible for a significant number of the traffic unsafety, and that making highways safer should be an important part of the measures to enhance traffic safety.


Traffic safety on highways is still not following the general descending or stagnating trend in general traffic. From 2004 forwards, the number of fatal and severely wounded victims on highways is continuously rising. Most of these accidents occur during intense traffic (morning and evening rush hour).


When classifying the accidents that occur between drivers, then the rear-end collision is most common: about 1/3 of all injuries. Chain collisions are rather limited, but have a larger impact regarding damage of the involved vehicles; the effect on traffic flow is also significant. For one-sided accidents, collisions with obstacles beside the road are most important: between 1991-2007 this varied between 39% en 45% of all injuries. When focusing on the condition of the road surface, the number of accidents in dry conditions is higher than in wet conditions.


From this analysis it can be concluded that traffic safety on highways can be enhanced when combining different measures. Besides applying ITS techniques, designing forgiving roads is a conditio sine qua non. Other elements such as enforcement, education and the engagement of all actors to contribute to traffic safety are not involved in this analysis, but obviously also determine the degree of safety.



A large number of ITS applications exist, which can be classified in several ways. In this report we will apply the classification based on technical operation. This means that we distinguish applications which have no interaction with data sources outside the vehicle, the so called autonomous applications, applications based on roadside systems where there is no interaction with data coming from individual vehicles, the autonomous roadside applications, and finally the applications where there is interaction between individual vehicles and other sources of data such as other vehicles, roadside infrastructure and internet services, the so called cooperative applications. This report gives an overview of the most important applications in each category.


Within the autonomous applications, these are: Electronic Stability Control, Emergency Brake Assist, Intelligent Speed Adaptation, Adaptive Headlights, Obstacle and collision warning, Autonomous Braking Systems, Lane Departure Warning System, Lane Changing Assistance, Fatigue Warning System and the Alcohol Lock.


For the autonomous roadside applications, these applications are most important: DRIP (Dynamic Route Information Panels) and GRIP (Grafic Route Information Panels), Real-Time Traffic Information (RTTI) and Floating Car Data.


Within the cooperative category the following applications matter most: Emergency Call (eCall), Breakdown Call, Floating Car Data, cooperative Real-Time Traffic Information (RTTI), Road Charging, Collision hazard warning, Road conditions information, Map updates, Dynamic Traffic Management and Recreative internet access.



An impact analysis of all these applications indicates that only a handful of this large number of applications has a large potential to enhance traffic safety. Introducing these applications should therefore be prioritized:

  • Electronic Stability Control: reduction of fatal and severely wounded with 15%.
  • Emergency Brake Assist: reduction of fatal and severely wounded with 17%.
  • Collision warning & avoidance: reduction of severely wounded with 16%.
  • Intelligent Speed Adaptation: reduction severely wounded 11%, fatalities 17%.
  • Advanced Adaptive Cruise Control: reduction of serverly wounded 11% (but only on highways such a high effect, for all roads this is just 2%)
  • Alcohol lock: reduction of fatalities with 6%, severely wounded 3%. If the target group can be selected specifically, then the effect is much higher.


On the technological field, communication technology is one of the pillars of future cooperative ITS systems. In previous policy research centre reports in this work package, technical characteristics of de different available communication technologies were already presented in detail, and theoretical properties such as available bandwidth were defined. In reality however, there is a deviation between those values and realistic values. Based on analysis and literature study, those realistic values are determined in this report for the following technologies: CEN DSRC, CALM M5, CALM IR, GPRS, UMTS, WiMAX, LTE, DAB and DVB.


To support applications based on local communication, more is needed then the base technology, all vehicles and roadside infrastructure should also form one local wireless network, a Vehicular Ad-Hoc Network (VANET). A known but open problem in this domain is the scalability problem. During high vehicle densities, the stringent requirements regarding delay and reliability cannot be fulfilled. This is a crucial problem for cooperative safety applications, and should be further researched.


Test environments are crucial. Different simulators are applied: three-dimensional driving simulators, network simulators and vehicle simulators. These tools are all easy accessible for the research community. Small scale test setups enable both testing of specific components and testing of entire applications, both in a laboratory setup and in real vehicles. These kind of setups are also quite common in current ITS research. Large scale test setup enable the same kind of tests, but on a large scale in a controlled environment. This form of test setups is still quite rare. It is recommended to adapt existing generic wireless test environments (such as the IBBT iLab.t Wireless Lab) to support these ITS tests. Field Operational Tests (FOT) are environments where applications are installed temporarily in the actual own vehicles of a large number of test users. On this moment the number of FOTs is limited, but under the impulse of Europe this will change in the very near future.


Regarding the number of relevant research projects we can remark that this is quite limited on a national level. The IBBT Next Generation ITS project (that finished in March 2010) is the only important example. On a European level on the other hand, huge efforts have been undertaken during the last years. Within the 6th European framework programme, a large number of projects have been executed, last of them finished mid-2010. The most important examples are: Intelligent Car Initiative, eSafety Forum, COMeSafety, Car 2 Car Consortium, GST, CVIS, Safespot, COOPERS, SEVECOM, eIMPACT, Feedmap, PReVENT, TRACE en AIDE. A large number of 7th framework projects is currently active, the most important ones are: FESTA, FOT-Net, euroFOT, TELEFOT, SIM-TD, GEONET, iTETRIS, PRE-DRIVE C2X en ROSATTE. From December 2009 until April 2010, a new call for projects was organized with the 7th framework programme, with a focus on executing FOTs and further developing ITS technology. These new projects will start in January 2011.



Effectively rolling out a complete ITS ecosystem enabling cooperative applications is not simple. A social- and technical-economical analysis provides new insights in the practical side of deployment. From the social-economical study it turns out that different individuals, companies and groupings are involved or influenced by the launch of an ITS. To turn this launch into a success, the different actors should interact in an appropriate way, if not their individual needs and demands could conflict. The network and the interactions can be divided using the PEST model: political, economical, social and technical aspects. A discussion of the most important stakeholders and interactions is given in the report: the producers, the users, interaction and economical factors, adoption of the system, and the government. Within the technical-economical analysis a cost model is essential. This was specifically constructed for this policy research. A first important aspect is the definition of the scenario: applied phases, capacity, applications and communication technology. Other important aspects are the capacity question, determination of the network, cost overview and cost modeling. The results of the cost model indicate that the most important cost driver is the on board unit (70% of total costs). Another important cost driver is CRM, or Client Relationship Management (18% of total costs). All other elements are far less important, never going over 3% of total costs. Based on this cost model, a number of cash flow simulations can be made to define a valid business case. In positive circumstances, a suitable subscription fee is 150 euro per vehicle per year. Regarding existing research, this is just within limits of what end users perceive as a reasonable price for ITS. In less positive circumstances, the price becomes 300 euro per vehicle per year. This is a bit higher then with current available commercial telematics systems that offer less functionality (eCall, breakdown call, stolen vehicle tracking) then in the envisaged scenario. Therefore the price seems to be just acceptable.



From all previous results, a number of policy recommendations can be derived. On a short term, the government can perform some minimal effort actions to gain a maximum result:

  • Put the European directive regarding the obligation of Electronic Stability Control and Emergency Brake Assist in practice on a national level.
  • Further support the road traffic signs database and stimulate ISA systems with sensibilisation campaigns or fiscal measures.
  • Systematically introduce alcohol locks as a penalty for repeating drunk drivers.
  • Stimulate further research regarding cooperative forms of collision warning & avoidance systems, in line with the European efforts. Points of attention are the scalability problem in Vehicular Ad-Hoc networks, application design and validation, business modeling and the setup of large scale testbeds and Field Operational Tests.

On a long term, the role of the government can be determined as follows:

  • It is required that the government places ITS on the agenda and gets all stakeholders on a single line. The government should not only practically observe ITS rollout, but should also support it over a long period, and sell it to all involved parties. Special attention should be given to the end users. A possible tool for this coordinating role could be the establishment of a platform for mutual communication.
  • A pricing model is required that determines how end users will contribute to the system. Without a doubt they will pay the most important costs, either directly or indirectly. It is useful to evaluate with them and producers if this should be done using a subscription, a one-time purchase or both.
  • The cost of the OBU is very significant. This should be kept in mind men looking for cost optimizations. International cooperation can prove to be useful (economies of scale principle).
  • An international standardization and certification procedure is required, both on the field of hard- and software, as on the elementary processes based on them.
  • A European approach seems very appropriate.
  • The legal framework for ITS has to be established. Responsibility and reliability of the different parties has to be defined, and abuse has to be taken into account. Privacy of users should be guaranteed at all time.
  • Practical organization is considerable. A number of tasks and responsibilities cannot be directly assigned, and could require the establishment of new companies. Good planning and timing is essential. The government is placed in a unique position to coordinate this. A private public partnership (PPP) seems a suitable organization form.
  • The government will have to determine how it wants to intermediate cost allocation: is there a need for regulations, taxes, or subsidies? To accelerate the launch and remove doubs of some actors, direct investments into the project also are a possibility.
  • The adoption can be one of the core problems during launch. When it is too slow, it can lead to an unsuccessful launch. When it is too fast, it can lead to very high initial investment costs. Further market research is required to be able to define measures to control adoption.
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