Filtern
Erscheinungsjahr
Dokumenttyp
Schlagworte
- Biomechanics (14) (entfernen)
Institut
- Abteilung Fahrzeugtechnik (14) (entfernen)
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.
Schutz von Fahrzeuginsassen
(1983)
Ausgehend von unfallstatistischen Daten und Ausführungen über Unfallablauf und Unfallfolgen werden Schutzmaßnahmen diskutiert, die das Verletzungsrisiko für Fahrzeuginsassen möglichst niedrig halten. Die Wirksamkeit von Schutzmaßnahmen wird beeinflusst von der Unfallkonstellation, Eigenschaften der Pperson und vom Fahrzeug (Deformationscharakteristik, Auslegung des rückhaltesystems). Die Gesamtwirksamkeit hängt wiederum ab von der Wirksamkeit des Rückhaltesystems, der Benutzungshäufigkeit und der Benutzungsqualität. Die Arbeit endet mit volkswirtschaftlichen Überlegungen und kommt zu dem Schluss, dass auch in Zukunft als wichtigste Maßnahme zum Schutz von Fahrzeuginsassen die Erhöhung der Anlegequote für Sicherheitsgurte anzusetzen ist.
The United Nations Economic Commission for Europe Informal Group on GTR No. 7 Phase 2 are working to define a build level for the BioRID II rear impact (whiplash) crash test dummy that ensures repeatable and reproducible performance in a test procedure that has been proposed for future legislation. This includes the specification of dummy hardware, as well as the development of comprehensive certification procedures for the dummy. This study evaluated whether the dummy build level and certification procedures deliver the desired level of repeatability and reproducibility. A custom-designed laboratory seat was made using the seat base, back, and head restraint from a production car seat to ensure a representative interface with the dummy. The seat back was reinforced for use in multiple tests and the recliner mechanism was replaced by an external spring-damper mechanism. A total of 65 tests were performed with 6 BioRID IIg dummies using the draft GTR No.7 sled pulse and seating procedure. All dummies were subject to the build, maintenance, and certification procedures defined by the Informal Group. The test condition was highly repeatable, with a very repeatable pulse, a well-controlled seat back response, and minimal observed degradation of seat foams. The results showed qualitatively reasonable repeatability and reproducibility for the upper torso and head accelerations, as well as for T1 Fx and upper neck Fx. However, reproducibility was not acceptable for T1 and upper neck Fz or for T1 and upper neck My. The Informal Group has not selected injury or seat assessment criteria for use with BioRID II, so it is not known whether these channels would be used in the regulation. However, the ramping-up behavior of the dummy showed poor reproducibility, which would be expected to affect the reproducibility of dummy measurements in general. Pelvis and spine characteristics were found to significantly influence the dummy measurements for which poor reproducibility was observed. It was also observed that the primary neck response in these tests was flexion, not extension. This correlates well with recent findings from Japan and the United States showing a correlation between neck flexion and injury in accident replication simulations and postmortem human subjects (PMHS) studies, respectively. The present certification tests may not adequately control front cervical spine bumper characteristics, which are important for neck flexion response. The certification sled test also does not include the pelvis and so cannot be used to control pelvis response and does not substantially load the lumbar bumpers and so does not control these parts of the dummy. The stiffness of all spine bumpers and of the pelvis flesh should be much more tightly controlled. It is recommended that a method for certifying the front cervical bumpers should be developed. Recommendations are also made for tighter tolerance on the input parameters for the existing certification tests.
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.