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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 flexible pedestrian legform impactor (FlexPLI) has been evaluated by a Technical Evaluation Group (Flex-TEG) of the Working Party on Passive Safety (GRSP) of the United Nations Economic Commission for Europe (UN-ECE). It will be implemented within phase 2 of the global technical regulation (GTR 9) as well as within a new ECE regulation on pedestrian safety as a test tool for the assessment of lower extremity injuries in lateral vehicle-to-pedestrian accidents (UN-ECE 2010-1, 2010-2 and 2010-3). Due to its biofidelic properties in the knee and tibia section, the FlexPLI is found to having an improved knee and tibia injury assessment ability when being compared to the current legislative test tool, the lower legform impactor developed by the Pedestrian Safety Working Group of the European Enhanced Vehicle-safety Committee (EEVC WG 17). However, due to a lack of biofidelity in terms of kinematics and loadings in the femur part of the FlexPLI, an appropriate assessment of femur injuries is still outstanding. The study described in this paper is aimed to close this gap. Impactor tests with the FlexPLI at different impact heights on three vehicle frontends with Sedan, SUV and FFV shape are performed and compared to tests with a modified FlexPLI with upper body mass. Full scale validation tests using a modified crash test dummy with attached FlexPLI that are carried out for the first time prove the more humanlike responses of the femur section with applied upper body mass. Apart from that they also show that the impact conditions described in the current technical provisions for tests with the FlexPLI don"t necessarily compensate the missing torso mass in terms of knee and tibia loadings either. Therefore it can be concluded that an applied upper body mass will contribute to a more biofidelic overall behavior of the legform and subsequently an improved injury assessment ability of all lower extremity injuries addressed by the FlexPLI. Nevertheless, the validity of the original as well as the modified legform for tests against vehicles with extraordinary high bumpers as well as flat front vehicles still needs to be evaluated in detail. A first clue is given by the application of an additional accelerometer to the legform.
Recent accident statistics from the German national database state bicyclists being the second endangered group of vulnerable road users besides pedestrians. With 399 fatalities, more than 14.000 seriously injured and more than 61.000 slightly injured persons on german roads in the year 2011, the group of bicyclists is ranked second of all road user groups (Statistisches Bundesamt, 2012). While the overall bicycle helmet usage frequency in Germany is very low, evidence is given that its usage leads to a significant reduction of severe head injuries. After an estimation of the benefit of bicycle helmet usage as well as an appropriate test procedure for bicyclists, this paper describes two different approaches for the improvement of bicyclist safety. While the first one is focusing on the assessment of the vehicle based protection potential for bicyclists, the second one is concentrating on the safety assessment of bicycle helmets. Within the first part of the study the possible revision of the existing pedestrian testing protocols is being examined, using in depth accident data, full scale simulation and hardware testing. Within the second part of the study, the results of tests according to supplemental test procedures for the safety assessment of bicycle helmets developed by the German Federal Highway Research Institute (BASt) are presented. An additional full scale test performed at reduced impact speed proves that measures of active vehicle safety as e.g. braking before the collision event do not necessarily always lead to a reduction of injury severity.
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.
Abstract: Für Kinder in Deutschland existiert im Pkw weiterhin ein höheres Risiko, im Straßenverkehr bei einem Unfall schwer verletzt oder getötet zu werden, als es für ungeschützte Verkehrsteilnehmer wie Fahrradfahrer oder Fußgänger besteht. Dies erscheint auf den ersten Blick nicht nachvollziehbar, da der Pkw und die vorgeschriebenen Kindersitze den Kindern eine hohe Sicherheit bieten müssten. Der vorliegende Projektbericht gibt Aufschluss über den aktuellen Stand der Sicherheit von Kindern im Pkw in Deutschland und zeigt Optimierungspotenzial auf. Die Schutzwirkung der Kindersitze hängt von mehreren Faktoren ab. Dabei stehen technische Aspekte, die hier detailliert untersucht wurden, im Vordergrund. Doch vor allem in den letzten Jahren zeigte sich immer wieder in Feldstudien, aber auch in der Unfallanalyse, dass Kinderschutzsysteme (KSS) oftmals nicht nach den Vorgaben installiert wurden. Wenn der Kindersitz und/oder das Kind nicht entsprechend der Bedienungsanleitung gesichert werden, kann sich das Schutzpotenzial der KSS reduzieren und gegen Null gehen. Im schlimmsten Fall stellt eine fehlerhafte Benutzung von KSS eine Gefahr sowohl für das Kind als auch für andere Pkw-Insassen dar. Die Unfallanalyse ergab keine Aussage darüber, ob verschiedene KSS-Modelle zu unterschiedlichen Verletzungsmustern führen, da die Unfallkonstellationen pro KSS-Modell zu verschieden waren. Des Weiteren wurde analysiert, inwieweit heutige Testverfahren mit diesen Konstellationen übereinstimmen. Das Ziel, mit wenigen Verfahren möglichst alle relevanten Unfälle abzubilden, wurde zum Teil ereicht. Zu viele Testverfahren mit unterschiedlichen Bewertungssystemen stellen heutzutage die Endverbraucher vor das Problem, dass nicht klar ist, welches KSS wirklich das beste ist. In der Realität hängt die Schutzwirkung zudem noch wesentlich von der KSS-Pkw-Kombination ab, die nur annähernd durch Versuche überprüft werden kann, da sich eine zu hohe Anzahl von Kombinationsmöglichkeiten ergibt. Anhand von mehr als 100 Versuchen wurde das Schutzpotenzial von verschiedenen aktuellen Kindersitzmodellen untersucht. Dabei wurden immer vermeintlich gute und schlechte KSS gegenübergestellt und unter gleichen Randbedingungen getestet. Ziel dieses Vorgehens war es, anhand der Messergebnisse Maßnahmen zu erkennen, die dem Schutz der Kinder dienlich sind. Zusammenfassend kann gesagt werden, dass prinzipiell für Kinder ein gutes Schutzniveau durch KSS besteht, was aber von KSS zu KSS verschieden sein kann. Die teureren KSS wiesen keine mechanische Zerstörung auf und überstanden alle Tests ohne ernsthafte Beschädigungen. Lediglich das oftmals als Dämpfungsmaterial eingesetzte Polystyrol nahm Energie auf und verformte sich wie vorgesehen plastisch. Bei den "Billig-Kindersitzen" ergab sich leider ein komplett anderes Bild. Sobald die Anforderungen über die der Gesetzgebung hinausgehen, ist immer weniger Schutz für die Kinder vorhanden. Besonders im Seitenaufprall offenbarten sich erhebliche Lücken in der Sicherheit. Dies reichte von mechanischem Versagen mancher Plastikteile bis hin zu konstruktiven Unzulänglichkeiten. Vor allem die Gurtführung muss deutlicher gekennzeichnet und mechanisch verstärkt werden. Trotz des hohen Schutzpotenzials einiger Kindersitze ist das Ende der Entwicklung noch nicht abzusehen. In allen Kindersitzklassen ist es prinzipiell möglich, die Belastungswerte weiter zu reduzieren. Dazu werden am Ende des Berichtes verschiedene Möglichkeiten aufgezeigt. Zum einen ist dies eine optimierte Babyschale, die durch eine Trägheitsbewegung gezielt Energie abbaut und das Baby in eine günstigere Position bringt, in der die Belastungen des Körpers reduziert sind. Zum anderen wird gezeigt, dass durch die feste Anbindung des KSS an den Pkw und die Reduzierung der Rotation um die Y-Achse die Belastungen für Kinder reduziert werden können. Größtes Entwicklungspotenzial bietet dabei das ISOFIX-System. Es ist bekannt, dass ISOFIX die Fehlbedienung des Kindersitzes und die Belastungen der Kinder deutlich reduzieren kann. Trotzdem ist die bisherige Marktdurchdringung von ISOFIX eher gering. Obwohl insgesamt ein positives Fazit gezogen werden kann, darf nicht aufgehört werden, die Kindersicherheit weiter zu verbessern. Denn nicht alle Kindersitze schützen heute gleich gut. Einige genügen lediglich den Gesetzesansprüchen und finden in vielen Fällen durch einen sehr geringen Verkaufspreis Zugang in die Pkw. Durch verschärfte Testbedingungen sollten diese Kindersitze abgeschafft und der Weg für neue und bessere Kinderschutzsysteme frei gemacht werden.
At the 2005 ESV conference, the International Harmonisation of Research Activities (IHRA) side impact working group proposed a 4 part draft test procedure, to form the basis of harmonisation of regulation world-wide and to help advances in car occupant protection. This paper presents the work performed by a European Commission 6th framework project, called APROSYS, an further development and evaluation of the proposed procedure from a European perspective. The 4 parts of the proposed procedure are: - A Mobile Deformable Barrier test; - An oblique Pole side impact test; - Interior headform tests; - Side Out of Position (OOP) tests. Full scale test and modelling work to develop the Advanced European Mobile Deformable Barrier (AE-MDB) further is described, resulting in a recommendation to revise the barrier face to include a bumper beam element. An evaluation of oblique and perpendicular pole tests was made from tests and numerical simulations using ES-2 and WorldSID 50th percentile dummies. It was concluded that an oblique pole test is feasible but that a perpendicular test would be preferable for Europe. The interior headform test protocol was evaluated to assess its repeatability and reproducibility and to solve issues such as the head impact angle and limitation zones. Recommendations for updates to the test protocol are made. Out-of-position (OOP) tests applicable for the European situation were performed, which included additional tests with Child Restraint Systems (CRS) which use is mandatory in Europe. It was concluded that the proposed IHRA OOP tests do cover the worst case situations, but the current test protocol is not ready for regulatory use.
Powered Two Wheeler (Motorcycle) crashes are overrepresented in EU, England, and United States casualty statistics for both fatal and serious injuries. While regional geographic differences are evident for motorcycle size, type, and engine displacement, the casualty statistics consistently indicate significantly higher injury rates for all motorcycle riders when compared to car occupants. Accident analysis and reconstruction of these motorcycle crashes is a necessary process to gain further understanding of potential injury mitigation strategies. This paper focuses on the analysis of the rider post impact trajectory in the immediate moments following a crash. The rider and motorcycle, while loosely coupled by seating position leading up to a crash, quickly decouple as the crash forces develop. As a result, the rider moves relative to the motorcycle and relative to the collision partner. This movement, or trajectory, is primarily influenced by the type and configuration of the impact, the type and configuration of the motorcycle and collision partner, and the speeds involved. Understanding the rider's post impact trajectory will assist in the development of injury mitigation strategies. Both the free flight trajectory of the rider and the rider's trajectory as influenced by interaction with the motorcycle and collision partner are examined. Rider trajectories in full scale crash testing and real world motorcycle crashes are both studied and presented. The resulting physical evidence that can be observed by an accident analyst is discussed. The application of projectile motion physics is analyzed and the necessary input parameters, such as initial launch angle, are studied. This study will assist in understanding the post-impact dynamics of a motorcyclist, and will provide useful information to analysts evaluating real world crashes.
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 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.
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.