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- Head on collision (23) (entfernen)
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Thorax injury is one of main causes of serious injury in frontal collisions, especially for elderly car occupants. The anthropometric test device (ATD) THOR‐M provides chest deflection measurements at multiple locations, to assess the risk of thorax injury. For this purpose e, risk functions are needed that relate the potential criteria based on multipoint chest deflection measurement to in jury risk. Different thorax injury criteria and risk functions for THOR have been proposed [2‐3]. The criteria and functions are based on the traditional approach to developing injury risk functions using matched ATD and PMHS tests by relating the injury (number of fractures) to injury criteria. Regarding these studies, some limitations have been identified, in particular concerning the loading conditions of the data used (mainly 3‐point‐belt loading, high loading severity, out‐of‐date ATD versions. To extend the data set and overcome these limitations, a new approach for improved thorax injury criteria was applied within the EC‐funded project SENIORS. The new approach is based on matched frontal impact sled computer simulations with a model representing the latest THOR‐M ATD version, and matching simulations with a human body model (HBM) representing an elderly car occupant.
Internationale Aktivitäten der Forschung auf dem Gebiet "Passive Sicherheit von Kraftfahrzeugen"
(2000)
Eine Fülle von Aktivitäten ist derzeit auf den Gebieten Frontal- und Seitenstoß zu beobachten, die in Europa auf den beiden entsprechenden EG-Richtlinien aufbauen. Das EEVC führt seine Arbeiten, an denen die Automobilindustrie beteiligt ist, fort; hier sind insbesondere die Arbeiten zum Seitenstoß (Kopfaufprall und Barrierenvergleich) zu nennen. Auf weltweiter Ebene beginnen die Arbeiten der IHRA (International Harmonised Research Activities) in ein konkretes Stadium der Zusammenarbeit einzutreten. Auf dem Gebiet der Seitenkollision ist längerfristig ein neues Testverfahren geplant, in das der von ISO entwickelte WORLD-SID einbezogen werden soll. Es gibt derzeit viele ernsthafte Bemühungen der Forschung um Harmonisierung. Auch wenn es nicht zu einer weltweiten Harmonisierung kompletter Regelungen kommt, so gibt es doch Hoffnung auf eine weltweite Harmonisierung von definierten Teilbestimmungen in speziellen Regelungen, so zum Beispiel bezüglich der Testmethode, der Versuchspuppen und der Bewertung der Schutzkriterien. Der Name des EEVC, European Enhanced Vehicle-safety Committee, steht für die Weiterentwicklung der Fahrzeugsicherheit. Die beteiligten Regierungen sind überzeugt, dass moderne Technologien neue Möglichkeiten eröffnen, um die Sicherheit der Kraftfahrzeuge weiter zu verbessern.
Bewertung der Fahrzeug-Fußraumintrusionen beim Offset Frontaltest gegen das Verformungselement
(1998)
In den Tests nach dem neuen Frontaltestverfahren (Entwürfe ECE R.94 sowie Richtlinie 96/79/EG und Ergänzung zu RL 70/156/EWG) entstehen hohe Verformungen der Fußräume der Versuchsfahrzeuge. Die Bewertung der Gefährdung der Insassen durch Intrusion, vorwiegend der Spritzwand begleitet von heftigen Bewegungen der Pedale, soll durch am Dummy zu messende Schutzkriterien erfolgen. Es ist vorgesehen, an den Dummies die Verschiebung des Schienbeins gegen das Knie, die Längskraft im Unterschenkel und den sogenannten Tibia Index zu messen. Um dieses zu ermöglichen, mussten an den vorhandenen Dummy-Unterschenkeln konstruktive Änderungen vorgenommen werden. Über die Herleitung der Schutzkriterien, Fragen bei der Anwendung dieser Kriterien sowie die technischen Einzelheiten und die Zertifizierung der neuen Dummy-Unterschenkel, welche die erforderlichen Messungen erlauben, wird berichtet.
Frontal impact is still the most relevant impact direction in terms of injury causation amongst car occupants. Especially for car-to-car frontal impacts the mass ratio between the involved vehicles has a significant impact on the injury risk (the heavier the opponent car the higher the injury risk). In order to address this issue frontal Mobile Deformable Barrier test procedures have been developed world-wide (for example the MPDB procedure that was fully described during the FIMCAR Project). The objective of this study was to investigate how vehicles of different weight classes perform in a mobile barrier test procedure compared to a fixed barrier test procedure (the full width rigid and offset deformable barrier test). Beyond that, the influence of vehicle mass and vehicle deformation on injuries was evaluated based on real world accident data. Five vehicle types were selected and tested in a fixed offset test procedure (ODB), a full width rigid barrier test procedure (FWRB) and a mobile offset test procedure (MPDB). For the accident analyses data from the German In-Depth Accident Study (GIDAS) was evaluated with a focus on MAIS 2+ injured belted front row car (UN-R 94 compliant cars) occupants in frontal impact accidents. Test data indicates higher dummy loadings, in particular for the head acceleration and chest acceleration, in the MPDB test for the vehicles with a mass lighter than the trolley (1,500 kg) compared to the FWRB test. The trend of increased vehicle stiffness (especially illustrated by tests with the MPDB and small cars) shows the need of a further improvement of passive restraint systems to reduce the occupant loading and with it the injury risk. The analyzed GIDAS data confirm the higher injury risk for occupants in cars with an accident weight of less than 1,500 kg compared to those with a crash weight above 1,500 kg in car-to-car and car-to-object or car-to-HGV, respectively. Furthermore the injury risk increases with decreasing mass ratio (i.e., the opponent car is heavier) in car-to-car accidents. Independent from the higher injury risk, the risk for passenger compartment intrusion in frontal impact appears not to be independent on the crash weight of the car.
In line with the new definition introduced by the European Commission (EC), the number of seriously injured road casualties in Germany for 2014 is assessed in this study. The number of MAIS3+ casualties is estimated by two different methodological approaches. The first approach is based on data from the German Inâ€Depth Accident Study (GIDAS), which is closely related to the German Road Traffic Accident Statistics. The second approach is based on data from the German TraumaRegister DGU-® (TRâ€DGU), which includes many more hospitals but not all MAIS3+ injuries.
The goal of the project FIMCAR (Frontal Impact and Compatibility Assessment Research) was to define an integrated set of test procedures and associated metrics to assess a vehicle's frontal impact protection, which includes self- and partner-protection. For the development of the set, two different full-width tests (full-width deformable barrier [FWDB] test, full-width rigid barrier test) and three different offset tests (offset deformable barrier [ODB] test, progressive deformable barrier [PDB] test, moveable deformable barrier with the PDB barrier face [MPDB] test) have been investigated. Different compatibility assessment procedures were analysed and metrics for assessing structural interaction (structural alignment, vertical and horizontal load spreading) as well as several promising metrics for the PDB/MPDB barrier were developed. The final assessment approach consists of a combination of the most suitable full-width and offset tests. For the full-width test (FWDB), a metric was developed to address structural alignment based on load cell wall information in the first 40 ms of the test. For the offset test (ODB), the existing ECE R94 was chosen. Within the paper, an overview of the final assessment approach for the frontal impact test procedures and their development is given.
Im Rahmen des weltweiten ESV-Programmes (Enhanced Safety of Vehicles) werden seit mehreren Jahren internationale Forschungsbemühungen unternommen (International Harmonized Research Activities, IHRA), um im Vorfeld der Gesetzgebung die wissenschaftlichen Grundlagen gemeinsam zu erarbeiten. Ziel der IHRA-Arbeiten ist es, auf der Grundlage dieser Forschungsergebnisse die Harmonisierung der Vorschriften zu erleichtern. Eine besondere Aktivität bezieht sich auf Intelligent Transportation Systems (ITS). Im vorliegenden Beitrag wird die Aufgabe dieser IHRA-ITS-Arbeiten geschildert, sowie der derzeitige Stand der Forschungsbemühungen beschrieben. Es zeigt sich, dass die beschriebene Sicherheitsbewertung eine Fülle von Fragestellungen aufwirft und weitere Forschungsanstrengungen erfordert. Die zukünftigen Bemühungen sind darauf gerichtet, in internationaler Zusammenarbeit und Arbeitsteilung die als besonders wichtig erkannten Themen zur Bewertung der fahrzeugseitigen Fahrerassistenzsysteme zu bearbeiten.
In the European Project FIMCAR, a proposal for a frontal impact test configuration was developed which included an additional full width deformable barrier (FWDB) test. Motivation for the deformable element was partly to measure structural forces as well as to produce a severe crash pulse different from that in the offset test. The objective of this study was to analyze the safety performance of vehicles in the full width rigid barrier test (FWRB) and in the full width deformable barrier test (FWDB). In total, 12 vehicles were crashed in both configurations. Comparison of these tests to real world accident data was used to identify the crash barrier most representative of real world crashes. For all vehicles, the airbag visible times were later in the FWDB configuration. This was attributed to the attenuation of the initial acceleration peak, observed in FWRB tests, by the addition of the deformable element. These findings were in alignment with airbag triggering times seen in real world crash data. Also, the dummy loadings were slightly worse in FWDB compared to FWRB tests, which is possibly linked to the airbag firing and a more realistic loading of the vehicle crash structures in the FWDB configuration. Evaluations of the lower extremities have shown a general increasing of the tibia index with the crash pulse severity.
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.
In general the passive safety capability is much greater in newer versus older cars due to the stiff compartment preventing intrusion in severe collisions. However, the stiffer structure which increases the deceleration can lead to a change in injury patterns. In order to analyse possible injury mechanisms for thoracic and lumbar spine injuries, data from the German Inâ€Depth Accident Study (GIDAS) were used in this study. A twoâ€step approach of statistical and caseâ€byâ€case analysis was applied for this investigation. In total 4,289 collisions were selected involving 8,844 vehicles, 5,765 injured persons and 9,468 coded injuries. Thoracic and lumbar spine injuries such as burst, compression or dislocation fractures as well as soft tissue injuries were found to occur in frontal impacts even without intrusion to the passenger compartment. If a MAIS 2+ injury occurred, in 15% of the cases a thoracic and/or lumbar spine injury is included. Considering AIS 2+ thoracic and lumbar spine, most injuries were fractures and occurred in the lumbar spine area. From the case by case analyses it can be concluded that lumbar spine fractures occur in accidents without the engagement of longitudinals, lateral loading to the occupant and/or very severe accidents with MAIS being much higher than the spine AIS.