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The European Enhanced Vehicle-safety Committee wants to promote the use of more biofidelic child dummies and biomechanical based tolerance limits in regulatory and consumer testing. This study has investigated the feasibility and potential impact of Q-dummies and new injury criteria for child restraint system assessment in frontal impact. European accident statistics have been reviewed for all ECE-R44 CRS groups. For frontal impact, injury measures are recommended for the head, neck, chest and abdomen. Priority of body segment protection depends on the ECE-R44 group. The Q-dummy family is able to reflect these injuries, because of its biofidelity performance and measurement capabilities for these body segments. Currently, the Q0, Q1, Q1.5, Q3 and Q6 are available representing children of 0, 1, 1.5, 3 and 6 years old. These Q-dummies cover almost all dummy weight groups as defined in ECE-R44. Q10, representing a 10 year-old child, is under development. New child dummy injury criteria are under discussion in EEVC WG12. Therefore, the ECE-R44 criteria are assessed by comparing the existing P-dummies and new Q-dummies in ECE-R44 frontal impact sled tests. In total 300 tests covering 30 CRSs of almost all existing child seat categories are performed by 11 European organizations. From this benchmark study, it is concluded that the performance of the Q-dummy family is good with respect to repeatability of the measurement signals and the durability of the dummies. Applying ECE-R44 criteria, the first impression is that results for P- and Q-dummy are similar. For child seat evaluation the potential merits of the Q-dummy family lie in the extra measurement possibilities of these dummies and in the more biofidelic response.
In the EC FP6 Integrated Project Advanced Protection Systems, APROSYS, the first WorldSID small female prototype was developed and evaluated by BASt, FTSS, INRETS, TRL and UPM-INSIA during 2006 and 2007. Results were presented at the ESV 2007 conference (Been et al., 2007). With the prototype dummy scoring a biofidelity rating higher than 6.7 out of 10 according to ISO/TR9790, the results were very promising. Also opportunities for further development were identified by the evaluation group. A revised prototype, Revision1, was subsequently developed in the 2007-2008 period to address comments from the evaluation group. The Revision1 dummy includes changes in the half arms and the suit (anthropometry and arm biomechanics), the thorax and abdomen ribs and sternum (rib durability), the abdomen/lumbar area and the lower legs (mass distribution). Also a two-dimensional chest deflection measurement system was developed to measure deflection in both lateral and anterior-posterior direction to improve oblique thorax loading sensitivity. Two Revision1 prototype dummies have now been evaluated by FTSS, TRL, UPM-INSIA and BASt. The updated prototype dummies were subjected to an extensive matrix of biomechanical tests, such as full body pendulum tests and lateral sled impact tests as specified by Wayne State University, Heidelberg University and Medical College of Wisconsin. The results indicated a significant improvement of dummy biofidelity. The overall dummy biofidelity in the ISO rating system has significantly improved from 6.7 to 7.6 on a scale between 0-10. The small female WorldSID has now obtained the same biofidelity rating as the WorldSID mid size male dummy. Also repeatability improved with respect to the prototype. In conclusion the recommended updates were all executed and all successfully contributed in achieving improved performance of the dummy.
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.
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.
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.
For the assessment of vehicle safety in frontal collisions, the crash compatibility between the colliding vehicles is crucial. Compatibility compromises both the self protection and the partner protection properties of vehicles. For the accident data analysis, the CCIS (GB) and GIDAS (DE) in-depth data bases were used. Selection criteria were frontal car accidents with car in compliance with ECE R94. For this study belted adult occupants in the front seats sustaining MAIS 2+ injuries were studied. Following this analysis FIMCAR concluded that the following compatibility issues are relevant: - Poor structural interaction (especially low overlap and over/underriding) - Compartment strength - Frontal force mismatch with lower priority than poor structural interaction In addition injuries arising from the acceleration loading of the occupant are present in a significant portion of frontal crashes. Based on the findings of the accident analysis the aims that shall be addressed by the proposed assessment approach were defined and priorities were allocated to them. The aims and priorities shall help to decide on suitable test procedures and appropriate metrics. In general it is anticipated that a full overlap and off-set test procedure is the most appropriate set of tests to assess a vehicle- frontal impact self and partner protection.
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.