Objective: Pedestrian lower extremity represents the most frequently injured body region in car-to-pedestrian accidents. The European Directive concerning pedestrian safety was established in 2003 for evaluating pedestrian protection performance of car models. However, design changes have not been quantified since then. The goal of this study was to investigate front-end profiles of representative passenger car models and the potential influence on pedestrian lower extremity injury risk.
Methods: The front-end styling of sedans and sport utility vehicles (SUV) released from 2008 to 2011 was characterized by the geometrical parameters related to pedestrian safety and compared to representative car models before 2003. The influence of geometrical design change on the resultant risk of injury to pedestrian lower extremity—that is, knee ligament rupture and long bone fracture—was estimated by a previously developed assessment tool assuming identical structural stiffness. Based on response surface generated from simulation results of a human body model (HBM), the tool provided kinematic and kinetic responses of pedestrian lower extremity resulted from a given car's front-end design.
Results: Newer passenger cars exhibited a “flatter” front-end design. The median value of the sedan models provided 87.5 mm less bottom depth, and the SUV models exhibited 94.7 mm less bottom depth. In the lateral impact configuration similar to that in the regulatory test methods, these geometrical changes tend to reduce the injury risk of human knee ligament rupture by 36.6 and 39.6% based on computational approximation. The geometrical changes did not significantly influence the long bone fracture risk.
Conclusions: The present study reviewed the geometrical changes in car front-ends along with regulatory concerns regarding pedestrian safety. A preliminary quantitative benefit of the lower extremity injury reduction was estimated based on these geometrical features. Further investigation is recommended on the structural changes and inclusion of more accident scenarios. 相似文献
Environmental protection policies in the automobile market were not implemented until the motorisation of the masses in the
1960s caused an increasing environmental burden. The rising air pollution was considered a latent danger to humans, animals
and plants. In the years up to 1985 the EU passed several regulations to limit the mass pollutants CO, CxHy and NOx. Germany
was the first EU-member nation to also be concerned with lead in gasoline, passing reduction regulations as early as 1971.
In 1986, several EU-member nations implemented the supply of unleaded gasoline. This decision was predominantly based on information
about widespread forest damage.
The reduction of lead emissions due to these regulations could be verified in different environmental systems. An example
of this was the decline of atmospheric lead concentrations and human blood lead levels in Germany. With regard to industries,
the German mineral oil and automobile markets were affected mostly. The price trend of gasoline was no longer only influenced by varying crude oil prices but also by tax discrimination between
leaded and unleaded fuel. With regard to the distribution system, the market positions particularly of the medium-sized traders
and the independent importers were weakened. In the automobile market, favourable terms of competition were experienced by
producers who had already gained experience with catalyst systems in the US market. The Gasoline Lead Content Regulations
had no significant effects on further economic indicators, except for competition.
Electronic Publication 相似文献
