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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.
Motorcycling is a fascinating kind of transportation. While the riders' direct exposure to the environment and the unique driving dynamics are essential to this fascination, they both cause a risk potential which is several times higher than when driving a car. This chapter gives a detailed introduction to the fundamentals of motorcycle dynamics and shows how its peculiarities and limitations place high demands on the layout of dynamics control systems, especially when cornering. The basic principles of dynamic stabilization and directional control are addressed along with four characteristic modes of instability (capsize, wobble, weave, and kickback). Special attention is given to the challenges of braking (brake force distribution, dynamic over-braking, kinematic instability, and brake steer torque induced righting behavior). It is explained how these challenges are addressed by state-of-the-art brake, traction, and suspension control systems in terms of system layout and principles of function. It is illustrated how the integration of additional sensors " essentially roll angle assessment " enhances the cornering performance in all three categories, fostering a trend to higher system integration levels. An outlook on potential future control systems shows exemplarily how the undesired righting behavior when braking in curves can be controlled, e.g., by means of a so-called brake steer torque avoidance mechanism (BSTAM), forming the basis for predictive brake assist (PBA) or even autonomous emergency braking (AEB). Finally, the very limited potential of brake and chassis control to stabilize yaw and roll motion during unbraked cornering accidents is regarded, closing with a promising glance at roll stabilization through a pair of gimbaled gyroscopes.
There is considerable evidence for the negative effects of driver distraction on road safety. In many experimental studies, drivers have been primarily viewed as passive receivers of distraction. Thus, there is a lack of research on the mediating role of their self-regulatory behavior. The aim of the current study was to compare drivers' performance when engaged in a system-paced secondary task with a self-paced version of this task and how both differed from baseline driving performance without distraction. Thirty-nine participants drove in a simulator while performing a secondary visual"manual task. One group of drivers had to work on this task in predefined situations under time pressure, whereas the other group was free to decide when to work on the secondary task (self-regulation group). Drivers' performance (e.g., lateral and longitudinal control, brake reaction times) was also compared with a baseline condition without any secondary task. For the system-paced secondary task, distraction was associated with high decrements in driving performance (especially in keeping the lateral position). No effects were found for the number of collisions, probably because of the lower driving speeds while distracted (compensatory behavior). For the self-regulation group, only small impairments in driving performance were found. Drivers engaged less in the secondary task during foreseeable demanding or critical driving situations. Overall, drivers in the self-regulation group were able to anticipate the demands of different traffic situations and to adapt their engagement in the secondary task, so that only small impairments in driving performance occurred. Because in real traffic drivers are mostly free to decide when to engage in secondary tasks, it can be concluded that self-regulation should be considered in driver distraction research to ensure ecological validity.
Although cruise control (CC) is available for most cars, no studies have been found which examine how this automation system influences driving behaviour. However, a relatively large number of studies have examined adaptive cruise control (ACC) which compared to CC includes also a distance control. Besides positive effects with regard to a better compliance to speed limits, there are also indications of smaller distances to lead vehicles and slower responses in situations that require immediate braking. Similar effects can be expected for CC as this system takes over longitudinal control as well. To test this hypothesis, a simulator study was conducted at the German Aerospace Center. Twenty-two participants drove different routes (highway and motorway) under three different conditions (assisted by ACC, CC and manual driving without any system). Different driving scenarios were examined including a secondary task condition. On the one hand, both systems lead to lower maximum velocities and less speed limit violations. There was no indication that drivers shift more of their attention towards secondary tasks when driving with CC or ACC. However, there were delayed driver reactions in critical situations, e.g., in a narrow curve or a fog bank. These results give rise to some caution regarding the safety effects of these systems, especially if in the future their range of functionality (e.g., ACC Stop-and-Go) is further increased.
Established in 1997, the European New Car Assessment Programme (Euro NCAP) provides consumers with a safety performance assessment for the majority of the most popular cars in Europe. Thanks to its rigorous crash tests, Euro NCAP has rapidly become an important driver safety improvement to new cars. After ten years of rating vehicles, Euro NCAP felt that a change was necessary to stay in tune with rapidly emerging driver assistance and crash avoidance systems and to respond to shifting priorities in road safety. A new overall rating system was introduced that combines the most important aspects of vehicle safety under a single star rating. The overall rating system has allowed Euro NCAP to continue to push for better fitment and higher performance for vehicles sold on the European market. In the coming years, the safety rating is expected to play an important role in the support of the roll-out of highly automated vehicles.
Euro NCAP will start to test pedestrian Automatic Emergency Braking Systems (AEB) from 2016 on. Test procedures for these tests had been developed by and discussed between the AsPeCSS project and other initiatives (e.g. the AEB group with Thatcham Research from the UK). This paper gives an overview on the development process from the AsPeCSS side, summarizes the current test and assessment procedures as of March 2015 and shows test and assessment results of five cars that had been tested by BASt for AsPeCSS and the respective manufacturer. The test and assessment methodology seems appropriate to rate the performance of different vehicles. The best test result - still one year ahead of the test implementation - is around 80%, while the worst rating result is around 10%. Other vehicles are between these boundaries.
Within the automotive context camera monitor systems (CMS) can be used to present views of the traffic situation behind the vehicle to the driver via a monitor mounted inside the cabin. This offers the opportunity to replace classical outside rearview mirrors and therefore to implement new design concepts, aerodynamically optimized vehicle shapes and to reduce the width of the vehicle. Further, the use of a CMS offers the potential to implement functionalities like warnings or situation-adaptive fields of view that are not feasible with conventional rearview mirrors. Despite these potential advantages, it is important to consider the possible technical constraints of this technology and its effect on driver perception and behavior. On the technical side next to the field of view and die robustness of die system, aspects as its functionality at day and night as well as under varying weather conditions should be object to scientific investigation. Concerning human machine interaction, it has to be considered, that the perception of velocities and distances of approaching vehicles might be different for CMS as compared to conventional rearview mirrors and potential influences of factors as the Position of the displays or drivers' age should be taken into account. In order to shed light on these and further open issues, BASt is currently conducting a study that will cover the use of CMS under controlled conditions as well in real traffic. The first part of the study will focus on passenger cars, while in a second step the empirical investigation will be extended to heavy goods vehicles, where the potentials as well as the limitations of CMS might differ considerably. The presentation will cover the first part, with regard to the experimental design, implementation and initial results if already available.
Many big cities in Europe and elsewhere in the world have problems managing the traffic especially during rush hours. The improvement of the parking problematic and environmental protection as well are important aspects for the future traffic design of urban areas. To improve the traffic situation the development of new traffic concepts and alternative vehicles are required. The BMW company has developed a new type of two-wheel vehicle. This two-wheeler constitutes a totally new concept. BMW implemented a lot of safety features, such as a structure made up of rollover bars and a crush element instead of a front protecting plate. Furthermore the driver can secure himself with two safety belts. The paper contains a description of the novel two-wheel vehicle concept designed so far. BMW's concept and the safety features are also explained. The Federal Highway Research Institute (BASt) was given the task of assessing the concept as a whole with regard to the active and passive safety and the exemption of the obligation to wear a helmet. The expertise concluded that the BMW two-wheeler concept has a very high safety standard. Some extracts of the expertise, in particular the investigations concerning the exemption of the obligation to wear a helmet are presented. Common legal requirements for the vehicle registration of vehicle concepts similar to the BMW two-wheeler in Germany have been formulated.
The GRSP informal group on child restraint systems (CRS) finalised phase 1 of a new regulation for the homologation of CRS . This regulation is the subject of several discussions concerning the safety benefits and the advantages and disadvantages that certain specific points may bring. However, these discussions are sometimes not based on scientific facts and do not consider the whole package but only single items. Based on the experience of the CASPER partners in the fields of human behaviour, accident analysis, test procedures and biomechanics in the area of child safety, a consideration of the safety benefits of phase 1 of the new regulation and recommendations for phase 2 will be given.
The EVERSAFE project addressed many safety issues for electric vehicles including the crash and post-crash safety. The project reviewed the market shares of full electric and hybrid vehicles, latest road traffic accident data involving severely damaged electric vehicles in Europe, and identified critical scenarios that may be particular for electric vehicles. Also, recent results from international research on the safety of electric vehicles were included in this paper such as results from performed experimental abuse cell and vehicle crash tests (incl. non-standardized tests with the Mitsubishi i-MiEV and the BMW i3), from discussions in the UN IG REESS and the GTR EVS as well as guidelines (handling procedures) for fire brigades from Germany, Sweden and the United States of America. Potential hazards that might arise from damaged electric vehicles after severe traffic accidents are an emerging issue for modern vehicles and were summarized from the perspective of different national approaches and discussed from the practical view of fire fighters. Recent rescue guidelines were reviewed and used as the basis for a newly developed rescue procedure. The paper gives recommendations in particular towards fire fighters, but also to vehicle manufacturers and first-aiders.
The use of proper child restraint systems (CRS) is mandatory for children travelling in cars in most countries of the world. The analysis of the quantity of restrained children shows that more than 90% of the children in Germany are restrained. Looking at the quality of the protection, a large discrepancy between restrained and well protected children can be seen. Two out of three children in Germany are not properly restrained. In addition, considerable difference exists with respect to the technical performance of CRS. For that reason investigations and optimisations on two different topics are necessary: The technical improvement of CRS and the ease of use of CRS. Consideration of the knowledge gained by the comparison of different CRS in crash tests would lead to some improvements of the CRS. But improvement of child safety is not only a technical issue. People should use CRS in the correct way. Misuse and incorrect handling could lead to less safety than correct usage of a poor CRS. For that reason new technical issues are necessary to improve the child safety AND the ease of use. Only the combination of both parts can significantly increase child safety. For the assessment of the safety level of common CRS, frontal and lateral sled tests simulating different severity levels were conducted comparing pairs of CRS which were felt to be good and CRS which were felt to be poor. The safety of some CRS is currently at a high level. All well known products were not damaged in the performed tests. The performance of non-branded CRS was mostly worse than that of the well known products. Although the branded child restraint systems already show a high safety level it is still possible to further improve their technical performance as demonstrated with a baby shell and a harness type CRS.
To improve vehicle safety in frontal collisions, the crash compatibility between the colliding vehicles is crucial. Compatibility aims to improve both the self and partner protection properties of vehicles. Although compatibility has received worldwide attention for many years, no final assessment approach has been defined. Within the Frontal Impact and Compatibility Assessment Research (FIMCAR) project, different frontal impact test procedures (offset deformable barrier [ODB] test as currently used for Economic Commission for Europe [ECE] R94, progressive deformable barrier test as proposed by France for a new ECE regulation, moveable deformable barrier test as discussed worldwide, full-width rigid barrier test as used in Federal Motor Vehicle Safety Standard [FMVSS] 208, and full-width deformable barrier test) were analyzed regarding their potential for future frontal impact legislation. The research activities focused on car-to-car frontal impact accidents based on accident investigations involving newer cars. Test procedures were developed with both a crash test program and numerical simulations. The proposal from FIMCAR is to use a full-width test procedure with a deformable element and compatibility metrics in combination with the current offset test as a frontal impact assessment approach that also addresses compatibility. By adding a full-width test to the current ODB test it is possible to better address the issues of structural misalignment and injuries resulting from high acceleration accidents as observed in the current fleet. The estimated benefit ranges from a 5 to 12 percent reduction of fatalities and serious injuries resulting from frontal impact accidents. By using a deformable element in the full-width test, the test conditions are more representative of real-world situations with respect to acceleration pulse, restraint system triggering time, and deformation pattern of the front structure. The test results are therefore expected to better represent real-world performance of the tested car. Furthermore, the assessment of the structural alignment is more robust than in the rigid wall test.
A legform impactor with biofidelic characteristics (FlexPLI) which is being developed by the Japanese Automobile Research Institute (JARI) is being considered as a test tool for legislation within a proposed Global Technical Regulation on pedestrian protection (UNECE, 2006) and therefore being evaluated by the Technical Evaluation Group (TEG) of GRSP. In previous built levels it already showed good test results on real cars as well as under idealised test conditions but also revealed further need for improvement. A research study at the Federal Highway Research Institute (BASt) deals with the question on how leg injury risks of modern car fronts can be revealed, reflected and assessed by the FlexPLI and how the impactor can be used and implemented as a legislative instrument for the type approval of cars according to current and future legislations on pedestrian protection. The latest impactor built level (GTα ) is being evaluated by a general review and assessment of the certification procedure, the knee joint biofidelity and the currently proposed injury criteria. Furthermore, the usability, robustness and durability as a test tool for legislation is examined and an assessment of leg injuries is made by a series of tests with the FlexPLI on real cars with modern car front shapes as well as under idealised test conditions. Finally, a comparison is made between the FlexPLI and the current european legislation tool, the legform impactor according to EEVC WG 17.
A means of assessing the passive safety of automobiles is a desirable instrument for legislative bodies, the automobile industry, and the consumer. As opposed to the dominating motor vehicle assessment criteria, such as engine power, spaciousness, aerodynamics and consumption, there are no clear and generally accepted criteria for assessing the passive safety of cars. The proposed method of assessment combines the results of experimental safety tests, carried out according to existing legally prescribed or currently discussed testing conditions, and a biomechanical validation of the loading values determined in the test. This evaluation is carried out with the aid of risk functions which are specified for individual parts of the body by correlating the results of accident analysis with those obtained by computer simulation. The degree of conformance to the respective protection criterion thus deduced is then weighted with factors which take into account the frequency of occurrence and the severity of the accident on the basis of resulting costs. Each of the test series includes at least two frontal and one lateral crash test against a deformable barrier. The computer-aided analysis and evaluation of the simulation results enables a vehicle-specific overall safety index as well as partial and individual safety values to be determined and plotted graphically. The passive safety provided by the respective vehicle under test can be defined for specific seating positions, special types of accident, or for individual endangered parts of the body.
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 off-set assessment procedure potentially contributes to the FIMCAR objectives to maintain the compartment strength and to assess load spreading in frontal collisions. Furthermore it provides the opportunity to assess the restraint system performance with different pulses if combined with a full-width assessment procedure in the frontal assessment approach. Originally it was expected that the PDB assessment procedure would be selected for the FIMCAR assessment approach. However, it was not possible to deliver a compatibility metric in time so that the current off-set procedure (ODB as used in UNECE R94) with some minor modifications was proposed for the FIMCAR Assessment Approach. Nevertheless the potential to assess load spreading, which appears not to be possible with any other assessed frontal impact assessment procedure was considered to be still high. Therefore the development work for the PDB assessment procedure did not stop with the decision not to select the PDB procedure. As a result of the decisions to use the current ODB and to further develop the PDB procedure, both are covered within this deliverable. The deliverable describes the off-set test procedure that will be recommended by FIMCAR consortium, this corresponds to the ODB test as it is specified in UN-ECE Regulation 94 (R94), i.e. EEVC deformable element with 40% overlap at a test speed of 56 km/h. In addition to the current R94 requirements, FIMCAR will recommend to introduce some structural requirements which will guarantee sufficiently strong occupant compartments by enforcing the stability of the forward occupant cell. With respect to the PDB assessment procedure a new metric, Digital Derivative in Y direction - DDY, was developed, described, analysed, and compared with other metrics. The DDY metric analyses the deformation gradients laterally across the PDB face. The more even the deformation, the lower the DDY values and the better the metric- result. In order analyse the different metrics, analysis of the existing PDB test results and the results of the performed simulation studies was performed. In addition, an assessment of artificial deformation profiles with the metrics took place. This analysis shows that there are still issues with the DDY metric but it appears that it is possible to solve them with future optimisations. For example the current metric assesses only the area within 60% of the half vehicle width. For vehicles that have the longitudinals further outboard, the metric is not effective. In addition to the metric development, practical issues of the PDB tests such as the definition of a scan procedure for the analysis of the deformation pattern including the validation of the scanning procedure by the analysis of 3 different scans at different locations of the same barrier were addressed. Furthermore the repeatability and reproducibility of the PDB was analysed. The barrier deformation readings seem to be sensitive with respect to the impact accuracy. In total, the deliverable is meant to define the FIMCAR off-set assessment procedure and to be a starting point for further development of the PDB assessment procedure.
The objective of this deliverable is to describe the expected influence of the candidate test procedures developed in FIMCAR for frontal impact on other impact types. The other impact types of primary interest are front-to-side impacts, collisions with road restraint systems (e.g. guardrails), and heavy goods vehicle impacts. These collision types were chosen as they involve structures that can be adapted to improve safety. Collisions with vulnerable road users (VRU) were not explicitly investigated in FIMCAR. It is expected that the vehicle structures of interest in FIMCAR can be designed into a VRU friendly shell. Information used for this deliverable comes from simulations and car-to-car crash tests conducted in FIMCAR or review of previous research. Three test configurations (full width, offset, and moving deformable barriers) were the input to the FIMCAR selection process. There are three different types of offset tests and two different full width tests. During the project test procedures could be divided into three groups that provide different influences or outcomes on vehicle designs: 1. The ODB barrier provides a method to assess part of the vehicles energy absorption capabilities and compartment test in one test. 2. The FWRB and FWDB have similar capabilities to control structural alignment, further assess energy absorption capabilities, and promote the improvements in the occupant restraint system for high deceleration impacts. 3. The PDB and MPDB can be used to promote better load spreading in the vehicle structures, in addition to assessing energy absorption and occupant compartment strength in an offset configuration. The consortium selected the ODB and FWDB as the two best candidates for short term application in international rulemaking. The review of how all candidates would affect vehicle performance in other impacts (beside front-to-front vehicle or frontal impacts with fixed obstacles) however is reported in this deliverable to support the benefit analysis reported in FIMCAR. The grouping presented above is used to discuss all five test candidates using similarities between certain tests and thereby simplify the discussion.
Despite the steadily declining number of pedestrian fatalities and injuries in most European countries during recent decades, pedestrian protection is still of great importance in the European Union as well as in Germany. This is because they still constitute a large proportion of road user casualties and are more likely to suffer serious and fatal injuries than most other road users. In 1999 only car occupants suffered more fatal injuries than pedestrians in Germany. In December 1998, EEVC WG 17 completed their review and updating of the EEVC WG 10 pedestrian test procedure that made it possible to evaluate the protection afforded to pedestrians by the front of passenger cars in an accident. Within the scope of this procedure, four different impactors are used representing those parts of the body which are injured very often and/or very seriously in vehicle-pedestrian-collisions. In a project executed by IKA and BASt, a small family car was tested according to the EEVC WG 17 test procedure. Afterwards modifications to the car were carried out in order to improve the pedestrian protection provided by the vehicle design. There were certain restrictions placed on the level of modifications undertaken, e.g. only minor modifications to vehicle styling and to the vehicle structures, which provide passenger protection. The redesigned vehicle was tested again using the WG 17 test procedure. The test results of the modified vehicle were compared with those of the standard vehicle and evaluated. The results show that considered measures for pedestrian protection in many areas of the vehicle front structure and the use of innovative techniques can lead to a significant reduction of the loads of pedestrians at an acceptable expense.
Since the beginning of the testing activities related to passive pedestrian safety, the width of the test area being assessed regarding its protection level for the lower extremities of vulnerable road users has been determined by geometrical measurements at the outer contour of the vehicle. During the past years, the trend of a decreased width of the lower extremity test and assessment area realized by special features of the outer vehicle frontend design could be observed. This study discusses different possibilities for counteracting this development and thus finding a robust definition for this area including all structures with high injury risk for the lower extremities of vulnerable road users in the event of a collision with a motor vehicle. While Euro NCAP is addressing the described problem by defining a test area under consideration of the stiff structures underneath the bumper fascia, a detailed study was carried out on behalf of the European Commission, aiming at a robust, worldwide harmonized definition of the bumper test area for legislation, taking into account the specific requirements of different certification procedures of the contracting parties of the UN/ECE agreements from 1958 and 1998. This paper details the work undertaken by BASt, also serving as a contribution to the TF-BTA of the UN/ECE GRSP, towards a harmonized test area in order to better protect the lower extremities of vulnerable road users. The German In-Depth Accident Database GIDAS is studied with respect to the potential benefit of a revised test area. Several practical options are discussed and applied to actual vehicles, investigating the differences and possible effects. Tests are carried out and the results studied in detail. Finally, a proposal for a feasible definition is given and a suggestion is made for solving possible open issues at angled surfaces due to rotation of the impactor. The study shows that, in principle, there is a need for the entire vehicle width being assessed with regard to the protection potential for lower extremities of vulnerable road users. It gives evidence on the necessity for a robust definition of the lower extremity test area including stiff and thus injurious structures at the vehicle frontend, especially underneath the bumper fascia. The legal definition of the lower extremity test area will shortly be almost harmonized with the robust Euro NCAP requirements, as already endorsed by GRSP, taking into account injurious structures and thus contributing to the enhanced protection of vulnerable road users. After finalization of the development of a torso mass for the flexible pedestrian legform impactor (FlexPLI) it is recommended to consider again the additional benefit of assessing the entire vehicle width.