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The utilisation of secondary-safety systems to protect occupants has attained a very high level over the past decades. Further improvements are still possible, but increasingly minor progress is only to be had with a high degree of effort. Thus, a key aspect must be the impact to overall safety in an accident. If reliable information is available on an imminent crash, measures already taken in the pre-crash phase can result in a significantly great influence on the outcomes of the crash. With this background preventive measures are the key to a sustainable further reduction of the figures of crash victims on our roads. This paper aims to show a preventive approach that can contribute to lessening the consequences of a crash by creating an optimum interaction of measures in the fields of primary and secondary safety. To further enhance vehicle safety, driver assistant systems are already available that warn the driver of an imminent front-to-rear-end crash. The next step is to support him in his reactions or if he fails to react sufficiently, to even initiate an automatic braking when the crash becomes unavoidable. Automatic pre-crash braking can, in an ideal situation, fully prevent a crash or can significantly reduce the impact speed and thus the impact energy (and the severity of the accident). If a vehicle is being braked in the pre-crash phase, the occupants are already being pre-stressed by the deceleration. The information available about the imminent crash can be used to activate the belt tensioners and likewise other secondary safety systems in the vehicle right before the impact. The pre-crash deceleration also causes the front of the vehicle to dip. Conventional crash tests do not take this specific impact situation into consideration. This is why, for example, the influences of the pre-crash displacements of the occupants are not recorded in the test results. Furthermore, a reproducible representation of the benefit of the vehicle safety systems which prepare the occupants for the imminent impact is not possible. In order to demonstrate the functions of automated pre-crash braking and to investigate the differences during the impact as a consequence of the altered occupant positions as well as the initiation of force and deformations of the vehicle front, DEKRA teamed up with BMW to carry out a joint crash test with the latest BMW 5 series vehicle. It involved the vehicle braking automatically from a starting test speed of 64 km/h (corresponding to the impact speed set by Euro NCAP) down to 40 km/h. The test was still run by the intelligent drive system of the crash test facility. This required several modifications to be made to the test facility as well as to the vehicle. The paper will describe and discuss some relevant results of the crash test. In addition, the possible benefits of such systems will also be considered. The test supplemented the work of the vFSS working group (vFSS stands advanced Forward-looking Safety Systems).
Nowadays human-created systems are increasing in complexity due to the interaction of humans and technology. Especially road traffic systems are composed of multitudinous resources (e.g. personnel, vehicles, organizations, etc.), which make it even harder to anticipate the positive and negative effects on safety. One key in achieving a significant reduction of fatalities is seen in driver assistant systems counterbalancing the lack of drivers' capabilities. But the actual outcome of implementing these sophisticated technologies especially on influencing driver's capabilities are yet unknown. Latest research exemplifies an increase of reaction times of drivers in case of dysfunctional driver assistant systems. This research paper applies STAMP/STPA (STAMP = systems-theoretic accident model and processes; STPA = systems-theoretic process analysis) to the German automobile traffic system focusing on the effects of driver assistant systems on drivers. By doing so, the potential hazards caused by technology can be identified.
The sequence of accident events can be classified by three essential phases, the pre-crash-sequence, the crash-sequence and the post-crash-sequence. The level of reliability of the information in the GIDAS-database (German In Depth Accident Study) is provided predominantly on the passive side. The period to evaluate active safety systems begins already in the pre-crash-sequence. The assessment of the potential of sensor- or communication-based active safety systems can only be accomplished by a detailed analysis of the pre-crash-phase. Hence the necessity to analyze the early period of the accident event in detail arises. This is possible with the help of the digital sketches of the accident site and the simulation of the accident by a simulation method of the VUFO GmbH. After simulating the pre-crash scenario it is possible to generate additional and standardized data to describe the pre-crash-sequences of an accident in a very high detail. These data are documented in a second database called the GIDAS Pre-Crash-Matrix (PCM). The PCM contains various tables with all relevant data to reproduce the pre-crash-sequence of traffic accidents from the GIDAS database until 5 seconds before the first collision. This includes parameters to describe the environment data, participant data and motion or dynamic data. This paper explains the creation of the PCM, the simulation itself and the contents and structure of the PCM. With this information of the pre-crash-sequence for various accident scenarios an improved benefit estimation and development of active safety systems can be made possible.
Rear-end collisions are the most frequent same and opposite-direction crashes. Common causes include momentary inattention, inadequate speed or inadequate distance. While most rear-end collisions in urban traffic only result in vehicle damage or slight injuries, rear-end collisions outside built-up areas or on motorways usually cause fatal or serious injuries. Driver assistance systems that detect dangerous situations in the longitudinal vehicle direction are therefore an essential safety plus. In view of this, for ADAC, systems that alert drivers to dangerous situations and initiate autonomous braking complement ESC as one of the most important active safety features in modern vehicles. The aim of ADAC is to provide consumers with technical advice and competent information about the systems available on the market. Reliable comparative tests that are based on standardised test criteria may provide motorists with important information and help them make a buying decision. In addition, they raise consumer awareness of the systems and speed up their market penetration. The assessment must focus on as many aspects of effectiveness as possible and include not only autonomous braking but also collision warning and autonomous brake assist. The work of the ADAC accident research is the development of the testing scenarios with direct link to accident situations and the identification of useful test criteria for testing.
The National Roads Authority in Ireland is responsible for planning and supervision of construction and maintenance works on the National Road network. Its primary function is "to secure the provision of a safe and efficient network of national roads". The population of Ireland has grown rapidly from 3.5 million to 4 million within the past 10 years, and vehicle ownership has also risen rapidly to 2 million vehicles, with 2.2 million drivers. Collisions rates in Ireland are at approximately 1.5 collisions per 1,000 population (in 2002), and 8.4 deaths per 1,000,000 population (in 2003). This ranked 8th out of the 15 countries in the European Union at the time. Ireland- current Road Safety Strategy includes Engineering Targets. These are to complete construction of certain lengths of new motorway, dual carriageway and 2+1 highway, to implement a certain number of accident remedial and traffic calming schemes, and to implement road safety audit on all new schemes. The accident remedial schemes, traffic calming schemes, and road safety audit are all the responsibility of the Road Safety section of NRA. The road safety programme of the NRA is divided into four main areas; a) accident remedial measures at individual sites, b) accident remedial treatment of entire routes, c) traffic calming of towns and villages on main roads, d) road safety audit. Examples of these measures are described. Evaluation of past programmes of single site accident remedial measures show a reduction in collision occurrence at these sites, but the effectiveness and the economic rate of return is decreasing over successive programmes. A similar programme has now been adopted on the rest of the country- road network, on regional and local roads. The programme of remedial treatment of entire routes has only recently started and has not been evaluated. Evaluation of the first programme of traffic calming of towns and villages shows an overall decrease in collisions and their severity, and a small reduction in speed. Road Safety Audit, examining new schemes a number of times during design and after construction, has been standard procedure on the national road network for nearly 6 years. An evaluation is currently underway.
The Swedish "Vision Zero" regards road fatalities and severe injuries as unacceptable. The vision is based on this ethical perspective together with a fundament of shared responsibility between the system designers and the road user. The design of the traffic system shall protect the road user from these effects as long as he or she follows the traffic rules. It should be possible to make a mistake without being killed. This policy has, during the first period of the "vision zero" (since 1997) put high priority on road and car design where the purpose has been to develop a forgiving environment. Gradually it has, however, become clear that much more effort has to be focused on the responsibility of the road user. Protecting measures will have limited effect as long as the understanding and acceptance from road users is limited. During the last years, Sweden has gone through several improvements of the driver education and is in the middle of important improvements of road safety education for children in schools. Several EU-projects has contributed to this development. One aspect that has received large international interest is the lay instructed driver training from 16 years of age supervised by parents. This has been in use since 1993. Another is the development of mandatory courses, such as an introduction for the learner and the lay instructor, a "risk awareness" courses dealing specifically with speeding, seat belt use, drunk driving, tiredness, and driving on low friction. The presentation will share some of the "vision zero" fundaments together with the latest experiences, research and development concerning driver education in Sweden.
Motorcycle safety research
(2007)
Honda- global motorcycle sales exceeded the 10 million units mark since 2004, and further expansion is expected. As a responsibility for a company to provide mobility, Honda is focusing on motorcycle safety as top priority and has been working on various activities for both aspects of hardware and software. Here, we present Honda- activity for the safety technology of motorcycles. At present, Honda is promoting motorcycle safety in the four themes of prevention and collision safety such as safety education, recognition assistance, accident prevention and injury reduction. First, in the area of the safety education, the "Honda Safety Driving Promotion Center" was established in 1970, and motorcycle riders and vehicle driver trainings have been organized, and the traffic training centers are used as an actual practice field not only in Japan but also in many other regions in the world. Through our training activities, the new area of safety training with hardware assistance was developed and Honda- unique technology was accumulated such as the riding simulator which can provide experience of potentially dangerous situations without risk. Especially, the "riding trainer", the popular version of the riding simulator, was introduced at several motor shows in various countries and launched in September 2005. It was distributed first in Europe and is expected to expand globally aiming at 3000 units worldwide.. And in Europe, the newest version, which includes the suburban roads program, jointly developed with ADAC, will be released in near future. In the area of recognition assistance, "vehicle to vehicle communication technology" is under development using the advantage of being a manufacturer of both motorcycles and cars. This technology is under research as Honda "ASV-3" in Japan, and as part of C2C activity in Europe. As for the accident prevention, advanced brake systems for motorcycles to assist more effective brake operation have been expanded, Honda signed the European Road Safety Charter in April 2004 with the advanced brake systems commitment and furthermore, they are expanding according to vehicle characteristics and region. Then all models above 250 cc will have a version of the system by 2010. And as the last theme, "motorcycle airbag system" is introduced which is equipped on a mass production motorcycle for the first time in the world. It has been researched and developed for a long time as an injury reduction technology for collision accidents. Honda automobile technology was used for the research and development of the motorcycle airbag, and many specific issues such as the analysis of the collision conditions particular to motorcycles have been solved to realize today- success. It might be known that ADAC in-house crash test held in August this year confirmed the high effectiveness of the airbag system and showed a positive result. This motorcycle airbag system is equipped to the Honda Gold Wing and launched in North America in August, 2006. Also in Europe, it will be sold by the end of this year. Each theme of Honda motorcycle safety technology can be seen at the Honda booth.
Every second counts when human lives are at stake. The increasingly safe design of vehicles presents rescuers with a serious challenge. Faced with high-strength steels and body reinforcements, even the most powerful cutters reach their limits. Therefore, incident commanders require information on the technical features and components installed, directly in the vehicle. Several tests have shown that such information helps to save valuable minutes. Therefore, a standardised A4 "rescue sheet" containing information on the location of cabin reinforcements, the tank, the battery, airbags, gas generators, control units etc. " and indicating adequate cutting points must be used throughout Europe. Hopefully, in a few years, the new eCall emergency call system will be in place everywhere in Europe. The system will transmit the relevant vehicle-specific data directly to the rescuers on-site. Until then, we need a simple and effective solution that saves lives.
The role of a national motor vehicle crash causation study-style data set in rollover data analysis
(2010)
On 1 January 2005, The National Highway Traffic Safety Administration, an agency of the United States Department of Transportation, implemented a new data collection strategy designed to assess crash avoidance technologies and report associated behavioral inputs and outcomes. The original goal was a six-year program, however, during the shortened data collection period; it proved a valuable resource for understanding a precrash environment previously obscured by forensic case investigation. Another unintended consequence was an overlap with infrastructure, roadway geometry, and design with the occupant and vehicle outcomes, by virtue of well-defined attributes. External to the collected data, supplementary information was extrapolated, by using manuals published in the United States, by the American Association of State Highway Transportation Officials and selected State Departments of Transportation, in conjunction with the National Motor Vehicle Crash Causation Study (NMVCCS). This provided a backdrop to the infrastructure framework of the rollover problem within which the occupant and vehicle outcomes were studied. If a NMVCCS-style data collection were to be implemented elsewhere, then complementary manuals produced by federal transportation officials might be consulted producing similar relationships. The current study uses NMVCCS data to describe vehicles travelling through diverse design geometries and the outcome for occupants involved in crashes within that system. Codified and extrapolated data form the basis for assessing NMVCCS and its value to the transportation safety community, as the protocols are applicable universally. The benefit in continuing a NMVCCS-style study is noted, as the interaction of roadway infrastructure and occupant protection agencies might find paths to better work together in solving the complex rollover problem using a common data-driven approach.
The overall purpose of the ASSESS project is to develop a relevant and standardised set of test and assessment methods and associated tools for integrated vehicle safety systems, primarily focussing on currently available pre-crash sensing systems. The first stage of the project was to define casualty relevant accident scenarios so that the test scenarios will be developed based on accident scenarios which currently result in the greatest injury outcome, measured by a combination of casualty severity and casualty frequency. The first analysis stage was completed using data from a range of accident databases, including those which were nationally representative (STATS19, UK and STRADA, SE) and in-depth sources which provided more detailed parameters to characterise the accident scenarios (GIDAS, DE and OTS, UK). A common analysis method was developed in order to compare the data from these different sources, and while the data sets were not completely compatible, the majority of the data was aligned in such a way that allowed a useful comparison to be made. As the ASSESS project focuses on pre-crash sensing systems fitted to passenger cars, the data selected for the analysis was "injury accidents which involved at least one passenger car". The accident data analysis yielded the following ranked list of most relevant accident scenarios: Rank Accident scenario 1 Driving accident - single vehicle loss of control 2 Accidents in longitudinal traffic (same and opposite directions) 3 Accidents with turning vehicle(s) or crossing paths in junctions 4 Accidents involving pedestrians The ranked list highlights the relatively large role played by "accidents in longitudinal traffic", and "accidents with turning vehicle(s) or crossing paths in junctions" (the second and third most prevalent accident scenarios, respectively). The pre-crash systems addressed in ASSESS propose to yield beneficial safety outcomes with specific regard to these accident scenarios. This indicates that the ASSESS project is highly relevant to the current casualty crash problem. In the second stage of the analysis a selection of these accident scenarios were analysed further to define the accident parameters at a more detailed level .This paper describes the analysis approach and results from the first analysis stage.
This work aims at bringing evidence for mass incompatibility in frontal impact for cars built according to the UNECE R94 regulation. French national injury accidents database census for years 2005 to 2008 were used for the analysis. The heterogeneity of frontal self-protection among cars of different masses is investigated, as well as the partner protection parameter offered by these cars. The last part of the analysis deals with the estimation of the benefit, in terms of fatal and severe injuries avoided, if crashworthiness was harmonized for the whole fleet of vehicle. This calculation is done for France and is extended to all Europe.
Over the past two decades the popularity of consumer crash test programs, commonly referred to as New Car Assessment Programs (NCAP), has grown across the world. They are popular among government regulators as they afford a means of promoting safety innovations and levels of vehicle performance beyond those dictated by national standards. They also fulfill the demand for information regarding the safety ranking of vehicles among consumers contemplating the purchase of a new vehicle. There is no question that consumer crash test programs greatly influence vehicle design changes as well as accelerate the fitment of new safety features. The extent to which these changes can be expected to reduce serious and potentially fatal injuries will be influenced by how well the testing protocols and associated rating schemes correctly reflect the nature of the residual safety problem they seek to address. Drawing on data contained primarily in the US National Automotive Sampling System (NASS), the field relevance of current and proposed testing and rating protocols addressing frontal crash test protection is examined. Emphasis is placed on examining how accurately injury rates computed from the dummy responses measured in consumer crash tests correspond to actual injury rates observed in the field. Additional data from Canadian field investigations and US databases such as the National Motor Vehicle Crash Causation Survey (NMVCCS) are examined to see how well frontal airbag firing times, crush pulse durations and other determinants of injury are replicated in consumer testing protocols. This portion of the analysis draws on data obtained from Event Data Recorders (EDR) in both field collisions and staged tests of the same vehicle model. Vehicle rankings and overall frontal crash test ratings were found to be particularly sensitive to the choice of injury risk functions employed in the test. This was particularly true in the case of injury risk functions used to assess neck injury potential. Neck injury risk derived from Nij was found to show the least agreement with the field. Agreement between field chest injury rates and those derived from crash tests was improved considerably when chest injury risk functions for "older" occupants were employed. The paper concludes with a discussion of how different current testing protocols could be improved to enhance their field relevance.
In road traffic accidents, a car-seat and its occupant can be subjected to various crash pulses in the case of a rear impact. This study investigates the influence of crash pulse shape on seat-occupant response and evaluates the corresponding risk of whiplash injury. For this purpose, a rigorously validated seat-occupant system model is used to study different carseat designs and crash pulses. Two different car-seat concepts are also presented which can effectively mitigate whiplash injury for a wide range of crash severity. It is shown that for crash pulses of similar severity, the level of whiplash-risk depends strongly on the combined effects of seat design and crash pulse shape.
Event Data Recorder (EDR) is an additional function installed in airbag control module (ACM) to record vehicle and occupant information for a brief period of time before, during, and after a crash event. EDRs are now being installed in ACMs by several automakers in the USA and in Japan. The aim of this study is to understand the performance of EDRs for the improvement of accident reconstruction with more reliable information. In the first report of the study, data obtained from EDRs of seven vehicle types were evaluated using 2006-2007 J-NCAP (Japanese new car assessment program) full-lap frontal barrier crash tests and offset frontal deformable barrier crash tests data. For more practical standpoint, we conducted thirteen crash tests reconstructing typical real-world accidents such as single vehicle accidents with barriers or poles, car to car accidents and multi rear-end collisions focusing on Japanese typical accident types. Data obtained from EDRs are compared with data obtained from optical speed sensor, instrumented accelerometers and high speed video cameras. The velocities determined from pre-crash data of EDRs and the maximum change in velocity, delta-V, and delta-V time history data obtained from post-crash data of EDRs are analyzed. The results are as follows: - Pre-crash velocities of EDRs were very accurate and reliable. An average difference between the EDR recording values and reference speeds was 4.2% and a root mean square of the differences was 9.2%. Only two cases resulted large differences for the pre-crash velocity. Both of them were cases with braking prior to the collision. However, another test with braking resulted less difference. The braking condition may influence accuracy of pre-crash velocities. - Maximum delta-Vs obtained from the EDRs showed uncertainty of measurement in several cases in comparisons with the reliable delta-V data. The differences in maximum delta-V were more than 10% in five of twenty-five events data and more than 20% in two of twenty-five events data. An average of the all differences was about 4% and root mean square of the differences was about 11%. Especially large deformation at narrow area may influence accuracy of post-crash delta-V. - Multiple rear-end crash tests were reconstructed using EDRs data as case studies. Some EDRs recorded two events and a time gap between two events, so that these reconstruction case studies were very accurate and reliable. - If though only one of three vehicles in multiple rear end crash was equipped EDR, overview and velocities of all cars may be reconstructed using these limited EDR data. In this case study, leading car- EDR data and middle car- EDR data were valuable. However if only following car was equipped EDR, the reconstruction was not accurate
Estimation of the benefits for the UK for potential options to modify UNECE Regulation No. 95
(2010)
The side impact problem in Europe remains substantial. UK data shows that between 22% and 26% of car occupant casualties are involved in a side impact, but this rises to between 29% and 38% for those who are fatally injured. This indicates the more injurious nature of side impacts compared with frontal impacts. The European Enhanced Vehicle safety Committee (EEVC) has performed work to address the side impact issue since 1979. As part of its continuing work, it has recently investigated potential options for regulatory changes to improve side impact protection in cars further. To support this work the UK undertook an analysis to estimate the benefit for potential options to modify UNECE Regulation 95. The analysis used the UK national STATS19 and detailed Co-operative Crash Injury Study (CCIS) accident databases. Of the potential options reviewed, it was found that the addition of a pole test offered the greatest benefit.
An analysis of NASS and FARS was conducted to determine crash conditions that involved injuries that are not currently being directly addressed by vehicle safety standards or by consumer information test protocols. Analysis of both field data and US NCAP tests were conducted to determine the relative safety provided by seating position and by vehicle model year. Opportunities for improvements were determined by crash categories with large populations of injuries that were not addressed by safety tests or smaller numbers that were increasing in frequency. Areas of opportunities include improved occupant restrain in rollovers, improved frontal protection for rear seat occupants and improved fire prevention in frontal and rollover crashes.
Since 2005, the motorcycle crash fatalities in the US exceeded 10% of the overall annual traffic fatalities. Consequently, it has become critical to gain in-depth understanding of the factors and characteristics contributing to motorcycle crashes. Unfortunately, there currently exists no database gathering the necessary information for an in-depth analysis of the US motorcycle crashes. So this study utilizes the NASS/CDS database (National Automotive Sampling System, Crashworthiness Data System) in order to gain insights into the patterns and factors leading to a NASS/CDS motorcycle crash, from 1997 to 2007. NASS/CDS samples about 5,000 passenger car tow-away crashes per year. Each case includes photographs and detailed data on crash and pre-crash characteristics, vehicle types, trajectories, types of impact, and other pertinent roadway and crash scene information, allowing an in-depth investigation of the crash mechanisms. However, the NASS/CDS sampling process specifically focuses on passenger car crashes, so the cases extracted only correspond to crashes in which a passenger vehicle was towed, and a motorcycle was somehow involved. Thus, a by-hand in-depth review of about 200 cases allowed retrieving 106 relevant crashes for this study, tending to represent the severe passenger vehicle(s) versus motorcycle(s) crashes on US roads. The findings lead to the conclusion that these crashes mostly result from the low conspicuity of the motorcycle, and from the inability of the car drivers to fully appreciate and anticipate the behavior of a motorcycle. Indeed, it has been shown that, first, the car drivers involved in these cases did not attempt any avoidance maneuver, second, they were largely of ages under 25, and finally, the majority of the crashes were in an intersection scenario. In addition, the two major scenarios unveiled were the car attempting a left turn from the opposite direction and the car attempting a left turn from the right. The paper mentions several solutions to enhance the motorcycle- conspicuity and to allow the car drivers to better anticipate its behavior, which seem to be key factors in the intersection-related crashes (and more generally in the passenger vehicle(s) versus motorcycle(s) crashes).
This study that was funded by the Research Association for Automotive Technology (FAT) develops a method for the evaluation of the placement of tanks or batteries by using the deformation frequencies in real-world accidents. Therefore, the deformations of more than 20.000 passenger cars in the GIDAS database are analysed. For each vehicle a contour of deformation is calculated and the deformed areas of the vehicles are transferred in a rangy matrix of deformation. Thereby, the vehicle is divided into more than 190.000 cells. Afterwards, all single matrices of deformation are summarized for each cell which allows representative analyses of the deformation frequencies of accidents with passenger cars in Germany. On the basis of these deformation frequencies it is possible to determine least deformed areas of all passenger cars. Furthermore, intended placements of tanks or batteries can be estimated in an early stage of development. Therefore, all vehicles with deformations in the intended tank areas can be analysed individually. Considering numerous parameters out of the GIDAS database (e.g. collision speed, kind of accident, overlap, collision partner etc.) the occurring forces can be calculated or the deformation frequency can be estimated. Furthermore, it is possible to consider the influence of primary and secondary safety systems on the deformation behaviour. The analysis of "worst case accident events" is an additional application of the calculated matrix of deformation frequency.
The paper presents a methodology for the benefit estimation of several secondary safety systems for pedestrians, using the exceptional data depth of GIDAS. A total of 667 frontal pedestrian accidents up to 40kph and more than 500 AIS2+ injuries have been considered. In addition to the severity, affected body region, exact impact point on the vehicle, and the causing part of every injury, the related Euro NCAP test zone was determined. One results of the study is a detailed impact distribution for AIS2+ injuries across the vehicle front. It can be stated, how often a test zone or vehicle part is hit by pedestrians in frontal accidents and which role the ground impact plays. Basing on that, different secondary safety measures can be evaluated by an injury shift method concerning their real world effectiveness. As an example, measures concerning the Euro NCAP pedestrian rating tests have been evaluated. It was analysed which Euro NCAP test zones are the most effective ones. In addition, real test results have been evaluated. Using the presented methodology, other secondary safety like the active bonnet (pop-up bonnet) or a pedestrian airbag measures can be evaluated.
Tree impacts are still one of the most important focal points of road deaths in Germany. For the year 2008, the latest figures in the national statistics show a share of 28% of road users killed in crashes with trees alongside a road amongst all crashes on rural roads (except the Autobahn). The official German statistics show the attribute "impact on a tree" since 1995. For this first reported year, the share of road users killed in such crashes was 30%. During the last 14 years, fatal accidents with road users killed on rural roads (except the Autobahn) after impacts on a tree declined by 60% from 1,737 (year 1995) to 696 (year 2008). But this is more or less in line with the general evolution of vehicle and traffic safety in Germany. For Germany as a whole the accident statistics do not show a reduction for "treer crashes" which is clearly more than the average for all accidents. But, as shown with the paper, there are different evolutions in the several German States. In public awareness the topic "tree impacts" is mostly associated with the situation in Germany after the reunification. At that time a lot of road users were killed on the avenues in the so called "new countries". The fact that "tree impacts" are still a big share within the figure of killed road users seems to be little-known. Using updated information coming from the official statistics and in-depth-studies, accident researchers can identify a big potential for further improvements of traffic safety on the associated district roads, state roads and federal highways. There is still a need to analyse more details of the accident occurrence with impacts on trees to generate new and updated findings on the current limits and potentials of measures to improve vehicle and traffic safety. To make further efforts in reducing the figures of victims of "tree impacts" the intensification of well-known conventional solutions " for example implementation of guard rails and reduction of speed - is an option. Measures related to vehicle safety technology especially in the field of primary (active) safety will have additional benefit within the physically imposed limits. With this background it can be seen that the subject "tree impacts" should be analysed with a holistic approach taking into account the entire system of driver, vehicle, road, the environment and a social consensus as well.
Looking at the total of sum of fatal car accidents the number of single-vehicle accidents and particularly run-offroad (ROR) accidents are most frequent. In Austria on the Autobahn ROR accidents amounts to almost 45% of all fatal accidents, i.e. nearly every second fatal accident is caused by ROR accidents and interaction with infrastructure. Approximately 43 people were killed on Autobahns in ROR accidents with passenger cars. One possibility of protection against impacts with infrastructure is the use of guardrails. However, the initial element identified as a turned down terminal could become a dangerous impact object. These turned down terminals may lead a vehicle to roll over or the car "takes-off" when impacting the turned down guardrail. In many cases it is reported that the vehicle is jumping into road side objects such as traffic sign poles or overpasses. On average, nine people are killed in such accidents every year in Austria.
Small overlap frontal crashes are defined by a damage pattern with most of the vehicle deformation concentrated outboard of the main longitudinal structures. These crashes are prominent among frontal crashes resulting in serious and fatal injuries, even among vehicles that perform well in regulatory and consumer information crash tests. One of the critical aspects of understanding these crashes is knowing the crash speeds that cause the types of damage associated with serious injuries. Laboratory crash tests were conducted using 12 vehicles in three small overlap test conditions: pole, vehicle-to-vehicle collinear, and vehicle-to-vehicle oblique (15-degree striking angle). Field reconstruction techniques were used to estimate the delta V for each vehicle, and these results were compared with actual delta V values based on vehicle accelerometer data. Estimated delta Vs were 50% lower than actual values. Velocity change estimates for small overlap frontal crashes in databases such as NASS-CDS significantly underestimate actual values.
Bone fracture patterns could be crucial in reconstructing the nature of loading, especially in the lower limb and upper limb kinematics in vehicle-pedestrian crashes. In addition, use of FE bone models can be a handy tool to predict vehicle impact velocity and the impact direction. The point of fracture initiation in bone loading has been predicted quite accurately earlier. A methodology that predicts bone crack initiation and its propagation pattern for the six known loading directions using a single material and failure model is presented.
Unfortunately, there has been a high number of accident fatalities reported in the Czech Republic in recent years. There are many causes which have led to a growth in the number of road traffic accidents. Since 1990, traffic density has demonstrated an upward moving tendency, daily traffic-jams are on the increase in many cities and traffic capacity on roads and streets is not able to satisfy this increasing density. Moreover, many road users lack experience in terms of driving modern cars. The National Accident Study of the Czech Republic is based on the assumption that the year 2010 is considered as a pilot project with the testing operation of collecting and evaluating data from traffic accidents. From the beginning of 2011, a fully-functional structure of the Traffic Accident Research will be created and solid data generated. Based on this assumption, we hope to begin meaningful cooperation with foreign countries.
Recent findings from real-world accident data have shown that fatality risks for pedestrians are substantially lower than generally reported in the traffic safety literature. One of the keys to this insight has been the large and random sample of car-to-pedestrian crashes available in the German In-Depth Accident Study (GIDAS). Another key factor has been the proper use of weight factors in order to adjust for outcome-based sampling bias in the accident data. However, a third factor, a priori of unknown importance, has not yet been properly analysed. This is the influence of errors in impact speed estimation. In this study, we derived a statistical model of the impact speed errors for pedestrian accidents present in the GIDAS database. The error model was then applied to investigate the effect of the estimation error on the pedestrian fatality risk as a function of car impact speed. To this end, we applied a method known as the SIMulation-EXtrapolation (SIMEX) method. It was found that the risk curve is fairly tolerant to some amount of random measurement error, but that it does become flattened. It is therefore important that the accident investigations and reconstructions are of high quality to assure that systematic errors are minimised and that the random errors are under control.
A national initiative from the vehicle manufacturers, safety system suppliers, the road administration and universities in Sweden took off in 2007. The aim was to develop a national investigation network and a methodology focusing on all phases of a crash (pre-crash, in-crash and post-crash) as well as all parts of the road transport system (road user, vehicle and road environment). The initiative is formally run as a project with the acronym INTACT (Investigation Network and Accident Collection Techniques). It was a three year pilot with the aim to develop methodologies for an extended national crash investigation activity. During the first year the INTACT partners agreed on the aim for the investigation and methods for retrieving the data were developed. During the second and third year the methodology was tested in real-world investigations and further refinement was made. The paper describes the methodology developed to obtain high qualitative in-depth road crash data.
In India, heavy truck crashes on national highways account for a number of fatalities. But due to lack of in-depth crash data, detailed analysis is not possible to determine injury mechanisms, and to identify infrastructure, vehicle and human factors affecting these crashes. Over the past two years, researchers in India have established a crash investigation network, with the co-operation of the police and hospitals, to conduct crash investigations and in-depth crash data collection on national highways in the state of Tamil Nadu. This pioneering effort has resulted in the development of a heavy truck crash investigation methodology, the outcome of which is scientific and reliable crash data that has been able to provide good insight into truck crashes and their causes. This paper explains the need for truck crash investigations, the methodology, conclusions of the data analyzed up to date, and the need to focus on truck driver working conditions.
Providing effective occupant protection in rollover crashes requires supplying the occupant with a restraint system proven effective in the dynamic rollover accident mode. Preventing ejection and providing restraint sufficient to prevent potentially injurious contacts with both interior and exterior vehicle components is paramount for effective rollover occupant protection. Research has shown that the injury potential can be decreased by closely coupling the occupant to the seat. This paper focuses on the effect of restraint system slack and its relationship to occupant excursion and ejection potential during rollover. Various restraint system configurations are evaluated in rollover-type test environments. A review of prior research is presented prior to presenting new quasi-static vehicle inversion studies conducted with live surrogate occupants. Additionally, dynamic rollover testing utilizing anthropometric test devices (ATDs) is presented. The influence of belt looseness and effects of various restraint designs on the belted occupants' injury potential are discussed.
Mechanical properties of tibial bone at compressive strain rates of 50-200 s-1 are obtained through Split Hopkinson pressure bar. Cylindrical specimens of 12-15 mm diameter and 2-5 mm thickness were used. The Young- moduli are calculated from linear portion of stress-strain curves. For both cortical and cancellous part of the bones, the Young- modulus was found to increase with the increasing strain rates. Also for both cancellous and cortical bones the Young- modulus increases consistently with increase in densities.
Among European Countries, Spain first issued a Standard, UNE 135900:2005, further updated in 2008, that deals with homologation and effectiveness evaluation of road restraint systems components designed to reduce harm for bikers impacting on them. An in depth analysis and critical review of this standard is reported in this paper. Beside a close examination of the standard requirements, numerical models of the crash test stated by the standard have been set up and simulated to study the effects of slight speed and approach angle variations on test results, remaining within tolerance gaps allowed by the standard. Model were validated against experimental data. Together with the expected increasing severity of the impact according with speed, a strong influence of approach angle on injury parameters was found. Possible improvements to the norm, in order to make it more robust, are suggested.
The need of passive safety devices, able to reduce the accidents and the severity of injuries suffered by motorcyclist, distinctly arises from data on accident statistics. In this paper, the effectiveness of an airbag device fitted in the biker- garments has been verified through various numerical simulations. Two simple test conditions were defined, in order to investigate the performance of the device both for back and front impacts, and simulated at various impact speeds. With the aim of providing more information about the actual capability of the airbag to reduce the severity of the injuries, one of accident scenario described by ISO 13232:2005 has been also investigated, checking the real effectiveness of the airbag strap-based firing system too. Confrontation of injury indexes resulting from simulation with and without airbag made possible a realistic evaluation of the harm reduction induced by the airbag presence.
Accident data shows that the vast majority of pedestrian accidents involve a passenger car. A refined method for estimating the potential effectiveness of a technology designed to support the car driver in mitigating or avoiding pedestrian accidents is presented. The basis of the benefit prediction method consists of accident scenario information for pedestrian-passenger car accidents from GIDAS, including vehicle and pedestrian velocities. These real world pedestrian accidents were first reconstructed and the system effectiveness was determined by comparing injury outcome with and without the functionality enabled for each accident. The predictions from Volvo Cars" general Benefit Estimation Model are refined by including the actual system algorithm and sensing models for a relevant car in the simulation environment. The feasibility of the method is proven by a case study on a authentic technology; the Auto Brake functionality in Collision Warning with Full Auto Brake and Pedestrian Detection (CWAB-PD). Assuming the system is adopted by all vehicles, the Case Study indicates a 24% reduction in pedestrian fatalities for crashes where the pedestrians were struck by the front of a passenger car.
An eCall device has been mounted on some vehicles in France since 2003. It is an integrated car radio/GSM/GPS system that can be used with a SIM card. When an accident occurs, a call can be sent manually or automatically made to a telephone call centre. Knowing the geographic location, the vehicle identity and the possibility of a direct communication with the people involved enables the nearest emergency services to be called out. In this context, the LAB / CEESAR have set up a study aimed at evaluating the effectiveness of this system. The purpose of this paper is to detail the E-call system evaluation method of effectiveness used and give a global synthesis of the results.
Females sustain Cervical Spine Distortion injury (CSD) more often than males. Most work dealing with the biomechanics background (e.g. injury mechanism/criteria) as well as the application in seat design/testing, focuses on the occupant model of an average male. Therefore the EU-Project ADSEAT (Adaptive Seat to Reduce Neck Injuries for Female and Male Occupants) is aimed at adding a female model for gender balanced research of CSD and improving seat design. An extensive literature review, searching for risk factors and injury criteria for males and females, was accompanied by the evaluation of different databases containing CSD cases. The database evaluations suggests that an anthropometry quite close to the 50%ile female anthropometry as known from crash test dummy design is appropriate. The results presented here form the basis for the future development of a computational female model and the improvement of seat design for better protection of both males and females in the frame of the ADSEAT-Project.
It has been pointed that most of the accidents on the roads are caused by driver faults, inattention and low performance. Therefore, future active safety systems are required to be aware of the driver status to be able to have preventative features. This probe study gives a system structure depending on multi-channel signal processing for three modules: Driver Identification, Route Recognition and Distraction Detection. The novelty lies in personalizing the route recognition and distraction detection systems according to particular driver with the help of driver identification system. The driver ID system also uses multiple modalities to verify the identity of the driver; therefore it can be applied to future smart cars working as car-keys. All the modules are tested using a separate data batch from the training sets using eight drivers" multi-channel driving signals, video and audio. The system was able to identify the driver with 100% accuracy using speech signals of length 30 sec or more and a frontal face image. After identifying the driver, the maneuver/ route recognition was achieved with 100% accuracy and the distraction detection had 72% accuracy in worst case. In overall, system is able to identify the driver, recognize the maneuver being performed at a particular time and able to detect driver distraction with reasonable accuracy.
The aim of this study was to evaluate the performance and accuracy of Event Data Recorders (EDRs). The analysis was based on J-NCAP crash tests from 2006"2007, with the corresponding EDR datasets. The pre-crash velocity, maximum delta-V and delta-V versus time history data recorded in the EDRs were compared with the reliable crash test data. The difference between the EDR pre-crash velocity and the laboratory test speed was less than 4 percent. In contrast, in several cases the maximum delta-V and delta-V versus time history data obtained from the EDRs showed uncertainty of measurement in comparisons with the reliable delta-V data. The difference in maximum delta-V in these comparisons was more than 5 percent in 10 of 14 tests and more than 10 percent in 4 of 14 tests. The EDRs underestimated the maximum delta-V in almost all tests. It was also concluded that the calculated acceleration from the EDR delta-V versus time history data showed good agreement with the instrumented accelerometer signal during the collision in almost all tests.
Impact severity is a fundamental measure for all in-depth crash investigation projects. One methodology used in the UK is based on the US Calspan software package CRASH3. The UK- in-depth crash investigation studies routinely use AiDamage3 a software package which is based on an updated version of the original CRASH3 algorithm, including enhancements to the vehicle stiffness coefficients. Real world accident-damaged vehicles are measured and their crush is correlated with a library of stiffness coefficients. These measurements are then used, along with other parameters, to calculate the crash energy and equivalent changes of velocity of the vehicles (delta-v), which is a measure of the impact severity. UK in-depth accident studies routinely validate the crash severity methodologies applied as the vehicle fleet changes. This is achieved by analysing crash test data and using the appropriate residual crush damage and other inputs to AiDamage3 and checking the program- outputs with the known crash severity parameters. This procedure checks, at least in part, the default stiffness values in the data libraries and the reconstruction methods used.
The focus of the technical innovation in the automobile industry is currently changing to sensor based safety systems, which are operating in the pre-crash phase of an accident. To get more information about this pre-crash phase for real accidents a simulation of this phase using the GIDAS database is done. The basics for this simulation are geometrical information about the accident location and the exact accident data out of the GIDAS database. This aggregated information gives the possibility to simulate an exact motion for every accident participant, using MATLAB / SIMULINK, in the pre-crash phase. After the simulation the information about the geometrical positions, the velocities and maneuvers of the drivers to an individual TTC (time to collision) are available. With those results it is possible to develop new useful sensor geometries using pre-crash scatter plots or estimate the efficiency of implemented active safety systems in combination with sensor characteristics. This simulation can be done for every reconstructed accident included in the GIDAS database, so these results can represent a wide spread basis for the further development of active safety systems and sensor geometries and characteristics
Over the last decades the number of traffic accident fatalities on German roads decreased by 77% down to 4968 in the year 2007. This positive development is due to optimisations of vehicle safety, roads and infrastructure and medical rescue issues. Up to now mostly the optimisations of secondary safety measures lead to this effect on vehicle safety. Since some years more and more driver assistance systems are available and lead to a further reduction of all accidents. These new systems are often comfort systems and have not primarily been developed to increase vehicle safety. In contrast to secondary safety systems primary safety systems are able to mitigate and avoid accidents. So in the future it is important to estimate the benefit of these systems in reducing accident numbers as well. Current benefit estimation methods mostly focus on a single system only and not on the combination of systems. In this paper a new method for a multivariate benefit estimation based on real accident data is developed. The paper describes the basic method to estimate the benefit of primary and secondary safety systems in combination. With the presented method the benefit will not be overestimated as it would be by a simple addition of the benefits of single systems. The model will be validated by a multivariate prospective benefit estimation of different vehicle safety systems in comparison to single benefit estimations of the same systems. For this the German In-Depth Accident Database is used. The results show the importance to implement the interactions of safety systems in the estimation process and rate the overestimation by a simple addition of the single system benefits. The validation includes primary and secondary safety systems in combination. The validation is done using more than 3500 real accidents which were initiated by cars. This sample out of the GIDAS database is representative for the current accident situation in Germany. The paper shows the necessity of a multivariate estimation of the benefit for existing and future safety systems.
A set of recommendations for pan-European transparent and independent road accident investigations has been developed by the SafetyNet project. The aim of these recommendations is to pave the way for future EU scale accident investigation activities by setting out the necessary steps for establishing safety oriented road accident investigations in Member States. This can be seen as the start of the process for establishing road accident investigations throughout Europe which operate according to a common methodology. The recommendations propose a European Safety Oriented Road Accident Investigation Programme which sets out the procedures that need to be put in place to investigate a sample of every day road accidents. They address four sets of issues; institutional addressing the characteristics of the programme; operational describing the conditions under which data isrncollected; data storage and protection; and reports, countermeasures and the dissemination of data.rn
Crash involvement studies using routine accident and exposure data : a case for case-control designs
(2009)
Fortunately, accident involvement is a rare event: the chance of an individual road user trip to end up in a crash is close to zero. Thus, according to general epidemiological principles one can expect the case-control study design to be especially suitable for quantifying the relative risk (odds ratio) of accident involvement of road users with a certain risk factor as compared to road users that do not have this characteristic. Ideally, of course, the database for such a case-control study should be established by drawing two independent random samples of cases (accidental units) and controls (nonaccidental units), respectively. If, however, special data collection is not an option, it is nevertheless possible to analyze routine accident and exposure data under a case-control design in order to fully exploit the information contained in already existing databases. As a prerequisite, accident and exposure data from different sources are to be combined in a single file of micro or grouped data in a way consistent with the case-control study design. Among other things, the proposed methodological approach offers the possibility to use in-depth data of the GIDAS type also in investigations of active vehicle safety by combining this data with appropriate vehicle trip data collected in mobility surveys.
Nowadays, traffic accidents are recorded in historical databases. Regarding the huge quantity of data, the use of data mining tools is essential to help Experts, for automatically extracting relevant information in order to establish and quantify relations between severity and potential factors of accidents. An innovative approach is here proposed for an in depth investigation of real world accidents data base. Mutual information ratio based on conditional entropies is used to quantity the association strength between an accident outcome descriptor (injury severity) and other potential association factors. Information theoretic methods help to select automatically groups of factors mostly responsible of the severity of accident.
Methods for analyzing the efficiency of primary safety measures based on real life accident data
(2009)
Primary safety measures are designed to help to avoid accidents or, if this is not possible, to stabilize respectively reduce the dynamics of the vehicle to such an extent that the secondary safety measures are able to act as good as possible. The efficiency of a primary safety measure is a criterion for the effectiveness, with which a system of primary safety succeeds in avoiding or mitigation the severity of accidents within its range of operation and in interactionwith driver and vehicle. Based on Daimler-´s philosophy of the "Real Life Safety" the reflection of the real world accidents in the systems range of operation is both starting point as well as benchmark for its optimization. This paper deals with the methodology to perform assessments of statistical representative efficiency of primary safety measures. To be able to carry out an investigation concerning the efficiency of a primary safety measure in a transparent and comparable way basic definitions and systematics were introduced. Based on these definitions different systematic methods for estimating efficiency were discussed and related to each other. The paper is completed by presenting an example for estimating the efficiency of actual "single" and "multi" connected primary safety systems.
As the official German catalogue of accident causes has difficulty in matching the increasing demands for detailed psychologically relevant accident causation information, a new system, based on a "7 Steps" model, so called ACASS, for analyzing and collecting causation factors of traffic accidents, was implemented in GIDAS in the year 2008. A hierarchical system was developed, which describes the human causation factors in a chronological sequence (from the perception to concrete action errors), considering the logical sequence of basic human functions when reacting to a request for reaction. With the help of this system the human errors of accident participants can be adequately described, as the causes of each range of basic human functions may be divided into their characteristics (influence criteria) and further into specific indicators of these characteristics (e.g. distraction from inside the vehicle as a characteristic of an observation-error and the operation of devices as an indication for distraction from inside the vehicle. The causation factors accordingly classified can be recorded in an economic way as a number is assigned to each basic function, to each characteristic of that basic function and to each indicator of that characteristic. Thus each causation factor can be explicitly described by means of a code of numbers. In a similar way the causation factors based on the technology of the vehicle and the driving environment, which are also subdivided in an equally hierarchical system, can be tagged with a code. Since the causes of traffic accidents can consist of a variety of factors from different ranges and categories, it is possible to tag each accident participant with several causation factors. This also opens the possibility to not only assign causation factors to the accident causer in the sense of the law, but also to other participants involved in the accident, who may have contributed to the development of the accident. The hierarchical layout of the system and the collection of the causation factors with numerical codes allow for the possibility to code information on accident causes even if the causation factor is not known to its full extent or in full detail, given the possibility to code only those cause factors, which are known. Derived from the systematic of the analysis of human accident causes ("7 steps") and from the practical experiences of on-scene interviews of accident participants, a system was set in place, which offers the possibility to extensively record not only human causation factors in a structured form. Furthermore, the analysis of the human causation factors in such a structured way provides a tool, especially for on-scene accident investigations, to conduct the interview of accident participants effectively and in a structured way.
In the last years various new driver information and driver assistance systems made their way into modern vehicles and there are yet countless systems underway. However, expenses for both, the development and the construction of these systems are tremendous. Therefore the interest of evaluating systems keeps growing steadily, not only regarding the results of systems developed in the last years but also regarding system ideas. Only if at least a rough benefit estimation is given, the industry can decide which development should be supported. However, there is still a lack of transparency of possible and useful methods for these kinds of estimations. These were analyses and structured in this study.
The aim of this study is to investigate the differences in car occupant injury severity recorded in AIS 2005 compared to AIS 1990 and to outline the likely effects on future data analysis findings. Occupant injury data in the UK Cooperative Crash Injury Study Database (CCIS) were coded for the period February 2006 to November 2007 using both AIS 1990 and AIS 2005. Data for 1,994 occupants with over 6000 coded injuries were reviewed at the AIS and MAIS level of severities and body regions to determine changes between the two coding methodologies. Overall there was an apparent general trend for fewer injuries to be coded at the AIS 4+ severity and more injuries to be coded at the AIS 2 severity. When these injury trends were reviewed in more detail it was found that the body regions which contributed the most to these changes in severity were the head, thorax and extremities. This is one of the first studies to examine the implications for large databases when changing to an updated method for coding injuries.
Internationally, the need is expressed for harmonized traffic accident data collection (PSN, PENDANT, etc.). Together with this effort of harmonization, traffic accident investigation moves more and more in the direction of accident causation. As current methods only partly address these needs, a new method was set up. The main characteristics of this method are: • Accident/injury causation (associated) factors can objectively be identified and quantified, by comparison with exposure information from a normal population. • All relevant accident and exposure data can be included: human-, vehicle-, and environmental related data for the pre-crash, crash and postcrash situation (the so-called Haddon matrix). The level of detail can be chosen depending on interest and/or budget, which makes the method very flexible. In this paper the accident collection and control group method are presented, including some of the achieved results from a pilot study on 30 truck accidents and 30 control locations. The data were analyzed by using cross-tabulations and classification-tree analysis. The method proved useful for the identification of statistically significant causational aspects.
Validation of human pedestrian models using laboratory data as well as accident reconstruction
(2007)
Human pedestrian models have been developed and improved continually. This paper shows the latest stage in development and validation of the multibody pedestrian model released with MADYMO. The biofidelity of the multibody pedestrian model has been verified using a range of full pedestrian-vehicle impact tests with a large range in body sizes (16 male, 2 female, standing height 160-192cm, weight 53.5-90kg). The simulation results were objectively correlated to experimental data. Overall, the model predicted the measured response well. In particular the head impact locations were accurately predicted, indicated by global correlation scores over 90%. The correlation score for the bumper forces and accelerations of various body parts was lower (47-64%), which was largely attributed to the limited information available on the vehicle contact characteristics (stiffness, damping, deformation). Also, the effects of the large range in published leg fracture tolerances on the predicted risk to leg fracture by the pedestrian model were evaluated and compared with experimental results. The validated mid-size male model was scaled to a range of body sizes, including children and a female. Typical applications for the pedestrian models are trend studies to evaluate vehicle front ends and accident reconstructions. Results obtained in several studies show that the pedestrian models match pedestrian throw distances and impact locations observed in real accidents. Larger sets of well documented cases can be used to further validate the models especially for specific populations as for instance children. In addition, these cases will be needed to evaluate the injury predictive capability of human models. Ongoing developments include a so-called facet pedestrian model with a more accurate geometry description and a more humanlike spine and neck and a full FE model allowing more detailed injury analysis.
The data situation for quantifying the proportion of accidents avoided by the introduction of active safety systems is incomplete, since there is generally no data available on the accidents avoided by the technology in question. In this paper, a split-register approach is suggested and compared with the classical case-control approach known from epidemiologic applications. Provided a set of assumptions hold, which can reasonably be made in such data situations, the split register approach allows inferences on the population accident risk. For both approaches the benefits of basing the analysis on the results of a logistic regression to adjust for confounding factors are outlined. The biasing effects of violating key assumptions are discussed and the split-register approach is demonstrated using the example of the active safety system ESP with data from the German in-depth accident study GIDAS.
Active safety systems are aimed at accident prevention, hence the knowledge required for their development is different from that required for passive safety systems aimed at injury prevention. Particularly, knowledge about accident causation is required. When looking at existing accident causation data, it is argued it fails to explain in sufficient detail how and why the accidents occur. Therefore, there is a need for detailed micro-level descriptions of accident causation mechanisms, and also of methodologies suitable for creating such descriptions. One study addressing these needs is the Swedish project FICA (Factors Influencing the Causation of Accidents and Incidents), where an accident investigation methodology suitable for active safety is developed, and in-depth accident investigations following this methodology are carried out on-scene in the area of Gothenburg by a multidisciplinary team. A preliminary aggregated analysis of different cases shows that the methodology developed is adequate for pointing out common contributing factors and devising principal countermeasures.
Electronic Stability Program (ESP) aims to prevent the lateral instability of a vehicle. Linked to the braking and powertrain systems, it prevents the car from running wide on a corner or the rear from sliding out. It also helps the driver control his trajectory, without replacing him, in the case of loss of control where the driver is performing an emergency manoeuvrer (confused and exaggerated steering wheel actions). A new ESP function optimizes ESP action in curves with hard under steering (situations in which the front wheels lose grip and the vehicle slides towards the outside of the curve). A complementary feature prevents the wheels from spinning when pulling away and accelerating. The name given to the ESP system varies according to the vehicle manufacturer, but other terms include: active stability control (ASC), automotive stability management system (ASMS), dynamic stability control (DSC), vehicle dynamic control (VDC), vehicle stability control (VSC) or electronic stability Control (ESC). This paper proposes an evaluation of the effectiveness of ESP in terms of reduction of injur accidents in France. The method consists of 3 steps: - The identification, in the French National injury accident census (Gendarmerie Nationale only), of accident-involved cars for which the determination of whether or not the car was fitted with ESP is possible. A sample of 1 356 cars involved in injury accidents occurred in 2000, 2001, 2002 and 2003 was then selected. But we had to restrict the analysis to only 588 Renault Lagunas. - The identification of accident situations for which we can determine whether or not ESP is pertinent (for example ESP is pertinent for loss of control accidents whilst it is not for cars pulling out of a junction). - The calculation, via a logistic regression, of the relative risk of being involved in an ESPpertinent accident for ESP equipped cars versus unequipped cars, divided by the relative risk of being involved in a non ESP-pertinent accident for ESP equipped cars versus unequipped cars. This relative risk is assumed to be the best estimator of ESP effectiveness. The arguments for such a method, effectiveness indicator and implicit hypothesis are presented and discussed in the paper. Based on a few assumptions, ESP is proved to be highly effective. Currently, the relative risk of being involved in an ESP pertinent accident for ESP-equipped cars is lower (-44%, although not statistically significant)rnthan for other cars.rn
Vehicle crash research at different levels is currently being conducted by several investigation groups in Spain, in some instances within various EU-funded projects. However there is a clear opportunity for increasing compatibility and maximizing usefulness, both at national and European levels, of the information collected by these groups. After reviewing on-going activities and programs in different countries, a framework for a nationwide crash investigation project is proposed: an organizational scheme is suggested as part of a future National Road Safety Strategic Plan; a map of investigation teams located in technological centres, universities and police agencies in Spain is presented; alternatives for several practical aspects such as team composition, deployment and operational budgets and project developmental stages are also discussed.
Institute for Traffic Accident Research and Data Analysis <Tokyo>rnAbstract: Analyses were conducted to clarify the features of rear-end collisions, using an integrated accident database developed by the Institute for Traffic Accident Research and Data Analysis (ITARDA). Focusing on neck injuries in rear-end collisions, analyses were made of the relation to struck-vehicle properties. Regarding the relation to the initial year of registration, the results did not show that newer vehicles tended to have a lower no-neck-injury rate, which was defined in this study as an index. On the contrary, in some passenger car classes, it was observed that the no-neck-injury rate was higher in newer vehicles. The effect of an active head restraint system, which is one type of anti-whiplash device, was analyzed by using not only the no-neck-injury rate but also a regression analysis. The results showed that the effect of an active head restraint system on suppressing the incidence of neck injuries was statistically significant.rn
The European Union has set a target to reduce all road fatalities (over 40,000) with 50% in 2010. This target percentage remained unchanged with the introduction of the ten new member states within the EU as by May 1st, 2004. According to Eurostat, 34% of all fatalities in 1998 in the, then, fifteen states of the European Union were the result of single vehicle collisions. This represents over 14,000 lives lost each year of which many can likely be saved through better roadside infrastructure design. The challenge for road safety professionals is to find methods and design strategies that help to reduce these casualties. Procedures for full-scale vehicle crash testing of guard rails were first published in the US in 1962. Present European regulation is mainly based on these procedures and later developments. Since then the vehicle fleet has changed considerably. Due to the complexity of the actual safety problem the numerical simulation approach offers a good opportunity to evaluate the different parameters involved in road safety, such as infrastructure properties, vehicle type, vehicle occupants and injuries. The ideal situation would be that simulation tools are coupled or integrated and all involved effects would be related. At the moment this is not the case yet, but initiatives are taken and a new virtual era has started. This paper offers a method looking at two components that encompass the driving environment: the car and the guardrail. As part of the EC-funded project, RISER (Roadside Infrastructure for Safer European Roads) a multi body simulation program study is carried out to determine sensitivities of some parameters in car to guardrail collisions and gives insides in performance of the car with passive safety equipment, the guardrail and the interaction of these objects with each other. By offering a set of methods that includes these two aspects and their intertwining relations, more confidence can be gained in actually reducing fatalities due to single vehicle collisions with, or due to, roadside furniture. Reducing the number of fatalities of single vehicle crashes would contribute greatly to the stated goal of reducing casualties altogether.
Due to recent years accident avoidance and crashworthiness on Austrian roads were mostly developed on national statistics and on-scene investigation respectively. Identification and elimination of black spots were main targets. In fact many fatal accidents do not occur on such black spots and black-spot investigation has reached a limit. New methods are required and therefore the Austrian Road Safety Programme was introduced by the Austrian Ministry of Transport, Innovation and Technology. The primary objective is the reduction of fatalities and severe injuries. Graz University of Technology initiated the project ZEDATU (Zentrale Datenbank tödlicher Unfälle) with the goal to identify similarities in different accident configurations. A matrix was established which categorizes risk and key factors of participating parties. Based on this information countermeasures were worked out.
NASS: the glass is half full
(2007)
The National Accident Sampling System (NASS) was born in the late 1970s. It was based on a substantial amount of experience and analysis of what was needed in the United States to understand the safety challenges of our highways. This work also showed how to collect high quality and useful crash data efficiently. Unfortunately, when Ronald Reagan - a President who believed in limited government - was elected, any hope of full funding for NASS was lost. The concept of 75 teams investigating about 18,000 serious crashes in detail annually was never realized. The system got up to 50 teams, then was cut to 36, and finally to 24 teams investigating fewer than a quarter of the originally anticipated number of crashes per year. Despite this, the NASS investigations provide a rich source of data, collected according to a sophisticated statistical sampling system to facilitate detailed national estimates of road casualties on our nation- highways and their causes. In addition, changes have been made in recent years to increase the number of more serious crashes of recent model vehicles to make the results more relevant to improving vehicle safety. A recent, detailed examination of hundreds of rollovers has provided considerable insight into rollover casualties and into what can be done to reduce them. Some of these results will be presented that show the value of the NASS system. Our experience with NASS and the Fatal Accident Reporting System (FARS) suggests a number of improvements that could be made in the United States" crash data systems. It also provides justification for a doubling or tripling of our national expenditures on crash data collection.
The objective of this study was to identify aspects of the individual experience and behaviour of drivers in intersection accidents. A total of 40 accident drivers sketched their ideas and expectations relating to intersection assistance using the method of Structure Formation Technique. Using this method prepared content cards and relation cards for a subject matter are formed together in a structure through the application of an explicit set of rules. The structures generated in this process were compared with the structures of 20 control persons who have not recently experienced an accident at intersections. The basis for this comparison was a case-control design with matched samples regarding the variables age, sex, education, occupation, driving experience and annual mileage. The results of the accident reports indicate that additional assistance is instrumental in the perception of other road users. Generally the interviewed drivers were open-minded towards the use of intersection assistance systems. Drivers who have recently experienced an accident at intersections significantly more often approved of warning assistance in their vehicle than drivers who have not recently experienced an accident. Further accident experienced drivers favoured warning and information via audio warning more frequently. The ideas of the drivers were strongly shaped by the experiences with already available advanced driver assistance systems. Hence acoustic and visual warnings were generally preferred to tactile warnings. The findings also indicate a relationship between the variable age and the acceptance of automatic vehicle intervention, and the suggestion of a head up display as a configuration of a visual warning system.
This study updates previous IIHS studies comparing estimated delta Vs for crash tested vehicles to the distribution of estimated delta Vs in the National Automotive Sampling System (NASS) Crashworthiness Data System (CDS). The delta V estimates for 232 frontal crash tests at 64.4km/h into a deformable barrier with 40 percent overlap are compared with estimates from frontal offset crashes in the 1997-2004 NASS database. All delta V estimates were based on SMASH, the delta V estimating program used by NASS since 1997. Results indicated that for all vehicles tested by IIHS, SMASH delta Vs were, on average, 32 percent lower than impact speeds and about 28 percent lower than the expected delta V. Almost 80 percent of all real-world frontal crashes resulting in AIS 3+ injuries and just over 60 percent of all fatal crashes occur at or below the average estimated delta V calculated for crash tested vehicles.
The price of a new car increased almost every year for a long period. In recent years however, the budget available to most people for purchasing a car either did not grow or became even smaller. Therefore it was in the interest of some OEMs to offer economical car models in the so-called "8,000- Euro class". Here an important question arose regarding the safety of these vehicles. There is no question that the very high safety level of cars reached in Europe during the last decades should not be sacrificed as a consequence of smaller budgets. Customers with sense of responsibility have the right to be properly informed about the balance between safety and price so that they can make a deliberate decision when buying either a new or a used car. Against this background, the German magazine "AutoBILD" commissioned DEKRA to conduct fullscale frontal crash tests with a view to publishing the results. These tests have been carried out in accordance with the corresponding Euro NCAP crash test requirements and performance criteria. The tested vehicles were two new Logans produced by the manufacturer Dacia, two used cars of the type VW Golf IV (registration date 2000) and one new VW Fox. This paper describes the safety features of the vehicles and the results of the five crash tests to demonstrate state-of-the-art safety levels and what levels may be expected from vehicles in the "8,000- Euro class". Looking at real-world crashes it is of interest to think about future trends in a more detailed manner. Therefore it will be more and more necessary to supplement the federal statistics with more detailed in-depth information about the consequences of accidents and the safety performance of crashed vehicles.
In recent years the boundaries between active and passive safety blurred more and more. Passive safety in the traditional term includes all safety aspects to prevent occupants to be injured or at least injury severity should be reduced. Passive Safety starts with the collision (first vehicle contact) and ends with rescue (open vehicle doors). Within this phase the occupant has to be protected by the passenger compartment whereby no intrusion should occur. Active safety on the other side was developed to interact prior to the collision whereby the goal is to prevent accidents. The extensive interaction between active and passive safety led to the terminologies "Primary" and "Secondary" safety whereas the expression Integrated Safety Concept was generated. Within this study the most well documented single vehicle accidents with cars not equipped with ESP were identified from the PENDANT database and reconstructed. Additional cases were found in the database ZEDATU of TU Graz. In comparison each case was simulated with the assumption that the cars were equipped with ESP. The differences regarding accident avoidance or crash severity as well as reduction of injury risk were analysed.
This paper uses the national accident statistics of Great Britain to evaluate the effectiveness of Electronic Stability Control Systems (ESC) to reduce crash involvement rates. The crash experience of 8,951 cars is analysed and compared to a closely matching set of non-ESC cars using case-control methods. This is one of the largest ESC samples analysed to date. Overall the cars with ESC are involved in 3% fewer crashes although the effectiveness is substantially higher under conditions of adverse road friction. ESC equipped cars are involved in 15% fewer fatal crashes although this reduction represents the combined effect of ESC and passive safety improvements.
There is a need for detecting characteristics of pedestrian movement before car-pedestrian collisions to trigger a fully reversible pedestrian protection system. For this purpose, a pedestrian sensor system has been developed. In order to evaluate the effectiveness of the sensor system, the in-depth knowledge of car-pedestrian impact scenarios is needed. This study aims at the evaluation of the sensor system. The accident data are selected from the STRADA database. The accident scenarios available in this database were evaluated and the knowledge of the most common scenarios was developed in terms of the pedestrian trajectory, the pedestrian speed, the car trajectory, the car velocity, etc. A mathematical model was then established to evaluate the sensor system with different detective angles. It was found that in order to detect all the pedestrians in the most common scenarios on time the sensor detective angle must be kept larger than 60 degrees.
Since 2005 the German In-Depth Accident Study (GIDAS) also records aspects of active vehicle safety. This is done because vehicles are fitted with an increasing number of active safety devices which have undoubtedly an influence on the number, severity and course of accidents. Accident researchers expect that collecting active safety data will facilitate to assess and quantify the impact of these and future devices. It is the aim of this paper to outline benefits and limitations associated with the recording of active safety aspects within indepth studies. An overview about possible areas where active safety data can be useful will be given. For that purpose single safety or comfort systems will be selected to estimate the effects of an accident database which includes variables associated with these systems. Questions with regard to the limitations of collecting active safety data will be addressed. Possible items are for example the usability of the data recorded, the real accident cause, the small number of relevant accidents, the time span needed to gather a sufficient dataset, the small share of vehicles equipped with a certain system or different functionalities of systems that are supposed to fall in the same category. As a result user needs for a reasonable data collection of active safety elements will be elaborated.
Road transport networks are of major importance for the economy and equally for the mobility of the citizens in the European countries. In order to improve the protection of transport infrastructures and the robustness of the European road network research projects are currently in process on national and European level. A main focus of these investigations is to analyze the specific vulnerabilities of bridges and tunnels concerning structural, operational and organizational aspects and to identify critical objects. But also infrastructures, which are critical due to their location and function in a road network, must be identified. For this the resulting regional and supra-regional impacts due to the failure of certain infrastructures have to be investigated on network level. In order to increase the security of road transport infrastructures and whole road networks the most effective security measures have to be determined. This paper gives an overview about the content and first results of current European and German research projects on road transport security.
As the data for road weather stations is used for online traffic control within section control systems, it is very important for the efficiency of the traffic control systems to be based on reliable data of a high quality. Therefore, a Test Site for checking the quality of road weather stations was established near Munich in Germany in 2003 and has been operational since then. In close co-operation with all participants (sensor manufacturers, road authorities, German Federal Research Institute, research and consultancy bodies), the overall goal was to improve the sensors" quality as well as to establish methods to detect failures in measurements. Furthermore, several improvements were carried out within the scope of the Test Site using the expertise of all participants and the infrastructure of the Test Site. The developments, reports and results obtained are both significant and helpful for manufacturers, road authorities, practitioners, research and consultancy.
This paper describes the methodology for the assessment of the socio-economic impact of SAFESPOT applications. The applications selected for the assessment cover vehicle to vehicle (v2v) as well as vehicle to infrastructure (v2i) communication systems. The applications address main problem areas of road safety: accidents at intersections, accidents due to hazardous road and weather conditions and accidents due to over speeding and inappropriate distance. The assessment methodology relies in its core on cost-benefit analysis (CBA) as the most widespread tool to assess the profitability of applications form the society point of view. The assessment is however not limited to CBA but also considers the economic effects for particular stakeholder groups such as users, public authorities and the like. Their individual cost and benefits can be investigated in stakeholder analyses. Both elements, CBA and stakeholder analysis, form an integrated assessment approach which is applied here. The assessment makes use of the sound methodological base which was provided by projects such as SEiSS and eIMPACT. Some characteristics of co-operative systems however call for special attention within the assessment. Most prominently, the assessment will concentrate on a bundle of applications. The impact of this bundle will be assessed under the conditions of different business and service models. These issues will be addressed in the paper. Moreover, this paper also provides insight in likely patterns of results and first results of socio-economic impact assessment itself.
With the present brake signal pattern the traffic behind only receives the information that the brakes are applied, however, the drivers have no information about the intensity of the braking maneuver. In this report it is examined on the basis of a study of the literature, how the rear signal pattern could be optimized for a special representation of emergency braking maneuvers. In principle there are two suitable possibilities to reduce the driver reaction time: - An increase in the area and luminance of the brake lights intuitively provide the drivers following with an impression of approaching the vehicle in front , - Flashing lights are particularly suited to attract the attention of the driver following to the deceleration of the vehicle ahead , - The following advancement is recommended as an optimization of the rear signal pattern: When the brake assistant or ABS actuates or at a vehicle deceleration rate greater than 7 m/s-², the emergency braking maneuver is signaled by flashing of the third high-mounted brake light at a rate of 3-5 Hz. As an option, the area and luminance of the two lower brake lights could be increased in addition. These measures require changes to ECE Regulations No. 7 and No. 48 as well as to the Vienna Convention. The purpose of the described solution is to reduce the number or severity of rear-end accidents.
The German Federal Ministry of Economics and Technology is funding a projectrncalled "Leistra2" with the aim of understanding the tire road contact and to find measures to reduce traffic noise, in particular to reduce the noise of tires rolling on pavements, i.e. tire-road noise. The project is composed out of three mayor subjects, low noise tires, low noise pavements and verification of the results, each made out of single sub-projects. The purpose of this paper is to give a survey about Leistra2 and to report about the latest activities and results. More detailed information and contact data of the partners involved can be found at http://www. LeiStra2.de. The program is the successor of the program LeiStra (Leiser Strassenverkehr), dealing with similar topics.rn
In spite of today's highly sophisticated crash test procedures like the different NCAP programs running world-wide, bad real world crash performance of cars is still an issue. There are crash situations which are not sufficiently represented by actual test configurations. This is especially true for car to car, as well as for car to object impacts. The paper describes reasons for this bad performance. The reasons are in principal bad structural interaction between the car and its impact partners (geometric incompatibility), unadjusted front end stiffness (stiffness incompatibility) and collapse of passenger compartments. To show the efficiency of improving cars' structural behaviour in accidents with different impact partners an accident data analysis has been taken out by members of European Project VC-COMPAT. Accident data analysis has shown that in Germany between 15,000 and 20,000 of the now severely injured car occupants might get less injured and between 600 and 900 car occupant fatalities might be saved. Similar results arise for the UK.
At the beginning of the year 2000 the European Commission set the goal to halve the number of road deaths till the year 2010. The main focus are passenger car and lorry traffic. A significant reduction of the accident data could be reached in these groups. The advancement of active vehicle safety systems is an important issue of the programme. The safety of the motorcycle traffic has been disregarded till now. Since 1991 the number of killed motorcycle riders per year has been constant. The number of killed passenger car occupants has been more than halved in the same period. This is why initiatives are caused for the increase of the motorcycle safety. A great safety potential is expected for the Antilock Brake System (ABS). ABS for motorcycles is considered from the economic view in this study. A cost-benefit analysis shall clarify whether the economic benefit of ABS for motorcycles is greater than the consumed resources. Moreover, a sensitivity analysis will determine the maximal justifiable consumption in resource for which ABS is worthwhile. After the sensitivity analysis is done a break-even analysis will determine the market price respectively the annual mileage from which on ABS is worthwhile on user level. For this the fair end consumer market price is calculated which the user is ready to pay. For the considered market prices the annual mileage is determined from which on ABS is worthwhile for the user. The considered time horizon for this analysis are the years 2015 and 2020. For each of these years the accident data is forecasted. At this, it is assumed that the frequency of having an accident per million registered motorcycles decreases based on the present trend. Thus, riding motorcycle gets safer. Hence, the accident data in the years 2015 and 2020 is lower than the accident data today. The cost-benefit analysis is done for each year for four scenarios. Two scenarios handle the market penetration. The first one is the trend scenario, the second one is the mandatory equipment from the year 2010 on. The other scenarios describe the effectiveness of ABS. The effectiveness rates are determined by a literature review. The only potential which can be considered due to the available data is the potential due to an avoiding of the downfall just before the real accident happens. According to this the number of accidents will decrease by 2.4 %. The number of fatalities will decrease by 12.1 %. The number of severe injuries decreases by 11.7 %. However, the number of slight injuries increases by 2.1 %. The mentioned effectiveness rates are valid for the scenarios with the high effectiveness. Even these figures underestimate the actual effectiveness because there are only considered the avoided accidents with downfall. The necessary consumption in resources depends on the produced volume. The more ABS systems are produced, the lower are the costs per system. This is due to realised effects of scale and effects out of learning curves. The system costs depend on the penetration rate. In the trend scenario the system costs for ABS are 120 Euro for the year 2015 respectively 105 Euro for the year 2020. In the mandatory scenario the system costs are 115 Euro for the year 2015 respectively 100 Euro for the year 2020. The benefit-cost ratios are all over the critical barrier of 1.0. Thus, ABS is worthwhile on economic level. In the scenarios with high effectiveness the benefit-cost ratios range between 4.6 and 4.9. Thus, the values are even above the barrier of 3.0. The result of the break-even analysis is that ABS is worthwhile on user level. The considered market prices are 400 Euro in 2015 and 300 Euro in 2020. They are clearly below the determined fair end consumer market prices. The fair end consumer price for the year 2015 is 701 Euro respectively 622 Euro for the year 2020. Thus, ABS is worthwhile for motorcycle riders with an annual mileage higher than 2,200 km (year 2015) respectively 1,900 km (year 2020). The annual mileage of a motorcycle rider is 3,900 km on average. Thus, ABS is worthwhile for most of the motorcycle riders. The mentioned results are valid for the high effectiveness scenarios.
In the framework of the OECD study "Moving Freight with Better Trucks", several vehicle combinations which are worldwide in operation were examined regarding different performance criteria. One criterion was the road wear performance of these articulated vehicles. With given tyre and vehicle data (mainly weights and axle loads) the road wear performance was calculated for each vehicle combination. The method according to COST 334 is presented and the vehicle combinations are compared