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Anhand von zwei verschiedenen Versuchskonfigurationen wurde das Schutzpotential von Kopfschutzsystemen (Fahrradhelm und airbagbasiertes System) untersucht. Hierbei wurden die resultierende Kopfbeschleunigung als Messwert sowie das Kopfverletzungskriterium HIC bei Versuchen ohne und mit Kopfschutzsystem vergleichend gegenübergestellt.
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 BASt-project group "Legal consequences of an increase in vehicle automation" has identified, defined and consequently compiled different automation degrees beyond Driver Assistance Systems. These are partial-, high- and full automation. According to German regulatory law, i.e. the German Road Traffic Code, it has been identified that the distinctive feature of different degrees of automation is the permanent attention of the driver to the task of driving as well as the constant availability of control over the vehicle. Partial automation meets these requirements. The absence of the driver- concentration to the traffic situation and to execute control is in conflict with the use of higher degrees of vehicle automation (i.e. high and full automation). Their use is therefore presently not compatible with German law, as the human driver would violate his obligations stipulated in the Road Traffic Code when fully relying on the degree of automation these systems would offer. As far as higher degrees of automation imply free-hand driving, further research in terms of behavioural psychology is required to determine whether this hinders the driver in the execution of permanent caution as required by sec. 1 para. 1 StVO (German Road Traffic Code). As far as liabilities according to the StVG (German Road Traffic Act) are concerned, the presently reversed burden of proof on the driver within sec. 18 para. 1 S. 2 StVG might no longer be considered adequate in case of higher degrees of automation that allow the driver to draw attention from the task of driving (in case making such use of a system would be permitted by the German Road Traffic Code). The liability of the vehicle "keeper", according to the German Road Traffic Act, would remain applicable to all defined degrees of automation. In case of partial automation, the use of systems according to their limits is accentuated. The range of use that remains within the intended must be defined closely and unmistakeably. Affecting user expectations properly can immensely help to maintain safe use, in case design-measures that exclude overreliance are not available according to the current state of the art (otherwise such measures would have to be applied primarily). In case of the higher degrees of automation that no longer require the driver- permanent attention (under the presupposition their use would be permitted by the German Road Traffic Code), every accident potentially bears the risk to cause product liability on the side of the manufacturer. Liability of the manufacturer might only be excluded in case of a breach of traffic rules by a third party or in case of overriding/ oversteering by the driver. In so far aspects of German procedural law and the burden of proof are of great importance. The project group has identified the need for further continuative research not only to advance legal assessment but also to improve basic technical conditions for vehicle automation as well as product reliability.
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.
For the assessment of vehicle safety in frontal collisions compatibility (which consists of self and partner protection) between opponents is crucial. Although compatibility has been analysed worldwide for over 10 years, no final assessment approach has been defined to date. Taking into account the European Enhanced Vehicle safety Committee (EEVC) compatibility and the final report to the steering committee on frontal impact [Faerber 2007] and the FP5 VC-COMPAT[Edwards 2007] project activities, two test approaches were identified as the most promising candidates for the assessment of compatibility. Both are composed of an off-set and a full overlap test procedure. In addition another procedure (a test with a moving deformable barrier) is getting more attention in current research programmes. The overall objective of the FIMCAR project is to complete the development of the candidate test procedures and propose a set of test procedures suitable for regulatory application to assess and control a vehicle- frontal impact and compatibility crash safety. In addition an associated cost benefit analysis will be performed. In the FIMCAR Deliverable D 3.1 [Adolph 2013] the development and assessment of criteria and associated performance limits for the full width test procedure were reported. In this Deliverable D3.2 analyses of the test data (full width tests, car-to-car tests and component tests), further development and validation of the full width assessment protocol and development of the load cell and load cell wall specification are reported. The FIMCAR full-width assessment procedure consists of a 50 km/h test against the Full Width Deformable Barrier (FWDB). The Load Cell Wall behind the deformable element assesses whether or not important Energy Absorbing Structures are within the Common Interaction Zone as defined based on the US part 581 zone. The metric evaluates the row forces and requires that the forces directly above and below the centre line of the Common Interaction Zone exceed a minimum threshold. Analysis of the load spreading showed that metrics that rely on sum forces of rows and columns are within acceptable tolerances. Furthermore it was concluded that the Repeatability and Reproducibility of the FWDB test is acceptable. The FWDB test was shown to be capable to detect lower load paths that are beneficial in car-to-car impacts.
For the assessment of vehicle safety in frontal collisions compatibility (which consists of self and partner protection) between opponents is crucial. Although compatibility has been analysed worldwide for over 10 years, no final assessment approach has been defined to date. Taking into account the European Enhanced Vehicle safety Committee (EEVC) compatibility and frontal impact working group (WG15) and the FP5 VC-COMPAT project activities, two test approaches have been identified as the most promising candidates for the assessment of compatibility. Both are composed of an off-set and a full overlap test procedure. In addition another procedure (a test with a moving deformable barrier) is getting more attention in current research programmes. The overall objective of the FIMCAR project is to complete the development of the candidate test procedures and propose a set of test procedures suitable for regulatory application to assess and control a vehicle- frontal impact and compatibility crash safety. In addition an associated cost benefit analysis should be performed. The objectives of the work reported in this deliverable were to review existing full-width test procedures and their discussed compatibility metrics, to report recent activities and findings with respect to full-width assessment procedures and to assess test procedures and metrics. Starting with a review of previous work, candidate metrics and associated performance limits to assess a vehicle- structural interaction potential, in particular its structural alignment, have been developed for both the Full Width Deformable Barrier (FWDB) and Full Width Rigid Barrier (FWRB) tests. Initial work was performed to develop a concept to assess a vehicle- frontal force matching. However, based on the accident analyses performed within FIMCAR frontal force matching was not evaluated as a first priority and thus in line with FIMCAR strategy the focus was put on the development of metrics for the assessment of structural interaction which was evaluated as a first priority.
The objectives of the FIMCAR (Frontal Impact and Compatibility Assessment Research) project are to answer the remaining open questions identified in earlier projects (such as understanding of the advantages and disadvantages of force based metrics and barrier deformation based metrics, confirmation of specific compatibility issues such as structural interaction, investigation of force matching) and to finalise the frontal impact test procedures required to assess compatibility. Research strategies and priorities were based on earlier research programs and the FIMCAR accident data analysis. The identified real world safety issues were used to develop a list of compatibility characteristics which were then prioritised within the consortium. This list was the basis for evaluating the different test candidates. This analysis resulted in the combination of the Full Width Deformable Barrier test (FWDB) with compatibility metrics and the existing Offset Deformable Barrier (ODB) as described in UN-ECE Regulation 94 with additional cabin integrity requirement as being proposed as the FIMCAR assessment approach. The proposed frontal impact assessment approach addresses many of the issues identified by the FIMCAR consortium but not all frontal impact and compatibility issues could be addressed.
Der vom 01.01.2012 bis zum 31.12.2016 andauernde Feldversuch der Bundesregierung mit Lang-Lkw wird durch die Bundesanstalt für Straßenwesen (BASt) wissenschaftlich begleitet. Lang-Lkw sind Fahrzeuge und Fahrzeugkombinationen, - die mit bis zu 25,25 m zwar länger als nach den geltenden Regelungen ausgeführt sein dürfen, - im Vergleich zu herkömmlichen Lkw um bis zu 6,50 m länger sind, - aber kein höheres Gesamtgewicht als die auch heute schon geltenden 40 t beziehungsweise 44 t im Vor- und Nachlauf zum Kombinierten Verkehr haben. Im Feldversuch werden die Chancen und Risiken des Einsatzes der Lang-Lkw untersucht. Nach etwa der Hälfte des Feldversuchs wurden die wesentlichen Erkenntnisse aus dem bisherigen Untersuchungszeitraum in einem Zwischenbericht von der BASt zusammengefasst und bewertet. Der Zwischenbericht der BASt gliedert sich thematisch und enthält neben den für die Konzeption der Gesamtuntersuchung erforderlichen rechtlichen Grundlagen und vorliegenden Erkenntnissen aus der Literatur insbesondere die Zusammenfassungen verschiedener Forschungsprojekte zu den hinsichtlich des Einsatzes von Lang-Lkw relevanten Fragestellungen. Die Teilprojekte, die von externen Forschungsnehmern bearbeitet wurden, sind als selbstständige Publikationen verfügbar. Dort finden sich detailliertere Informationen zu den einzelnen Untersuchungen. Insgesamt galt es herauszuarbeiten, welche Auswirkungen der Einsatz von Lang-Lkw im Vergleich zur Situation ohne Lang-Lkw auf die identifizierten Fragestellungen hat. Zusammenfassend lässt sich feststellen, dass sich neben den festgestellten positiven Effekten, wie einem Effizienzgewinn und der Einsparung von Lkw-Fahrten, gravierende Probleme im Feldversuch unter den gegebenen Randbedingungen bislang nicht gezeigt haben. Gemessen an der Vielzahl betrachteter Fragestellungen ist die Anzahl der identifizierten Risiken gering. Zudem sind die identifizierten Risiken bei der derzeit vorhandenen Anzahl von im Feldversuch beteiligten Lang-Lkw und auch noch unter der Annahme von deutlich höheren Anteilen von Lang-Lkw am Güterverkehrsaufkommen als hinnehmbar oder zumindest beherrschbar einzustufen. Einzig für den Umstand der für Lang-Lkw in der Regel zu kurzen Schrägparkstände auf Rastanlagen müssten bei einer steigenden Anzahl an Lang-Lkw Lösungsansätze entwickelt werden, um das regelkonforme Abstellen der Lang-Lkw auch auf Rastanlagen weiterhin gewährleisten zu können. Zu beachten ist hinsichtlich der Gesamteinschätzung zudem, dass den erzielten Ergebnissen in der Regel die ganz spezifischen Randbedingungen des Feldversuchs zugrunde liegen. Teilweise resultieren diese Randbedingungen aus den Vorgaben der Ausnahme-Verordnung zum Feldversuch, in Einzelfällen auch aus dem unter Versuchsbedingungen angepassten Verhalten der Lang-Lkw-Fahrer. Sofern sich an diesen Randbedingungen Änderungen einstellen sollten oder die Unternehmen die heute geltenden Freiheitsgrade deutlicher ausnutzen, sind gewisse Fragestellungen neu zu beleuchten. Somit zeigt der Zwischenbericht in seinem Fazit zusammenfassend auf, dass an einzelnen Punkten weiter Forschungsbedarf besteht. Bis zum Ende des Feldversuchs wird die BASt diesen Fragen nachgehen und Nacherhebungen zur Validierung der bisherigen Ergebnisse durchführen können.
Cost benefit analysis
(2014)
Although the number of road accident casualties in Europe is falling the problem still remains substantial. In 2011 there were still over 30,000 road accident fatalities [EC 2012]. Approximately half of these were car occupants and about 60 percent of these occurred in frontal impacts. The next stage to improve a car- safety performance in frontal impacts is to improve its compatibility for car-to-car impacts and for collisions against objects and HGVs. Compatibility consists of improving both a car- self and partner protection in a manner such that there is good interaction with the collision partner and the impact energy is absorbed in the car- frontal structures in a controlled way which results in a reduction of injuries. Over the last ten years much research has been performed which has found that there are four main factors related to a car- compatibility [Edwards 2003, Edwards 2007]. These are structural interaction potential, frontal force matching, compartment strength and the compartment deceleration pulse and related restraint system performance. The objective of the FIMCAR FP7 EC-project was to develop an assessment approach suitable for regulatory application to control a car- frontal impact and compatibility crash performance and perform an associated cost benefit analysis for its implementation.