Improved assessment methods of lower extremity injuries in vehicle-to-pedestrian accidents using impactor tests and full-scale dummy tests

Zander, Oliver; Gehring, Dirk-Uwe; Leßmann, Peter

Affiliations

¹Federal Highway Research Institute (BASt), Germany

²BGS Böhme & Gehring GmbH, Germany

Abstract

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.

Links

URL: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv22/22ESV-000079.pdf

Cited Works (6)

Year	Entry
2009	Zander O, Gehring D-U, Leßmann P, Bovenkerk J. Evaluation of a flexible pedestrian legform impactor (Flex-PLI) for the implementation within legislation on pedestrian protection. In: Proceedings of the 21st International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 15-18, 2009; Stuttgart, Germany.
2001	Konosu A, Ishikawa H, Tanahashi M. Reconsideration of injury criteria for pedestrian subsystem legform test: problems of rigid legform impactor. In: Proceedings of the 17th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 4-7, 2001; Amsterdam, The Netherlands.
1985	Nyquist GW, Cheng R, El-Bohy AAR, King AI. Tibia bending: strength and response. In: Proceedings of the 29th Stapp Car Crash Conference. October 9-11, 1985; Washington, DC. Warrendale, PA: Society of Automotive Engineers:99-112. SAE 851728.
2003	Kerrigan JR, Bhalla KS, Madeley NJ, Funk JR, Bose D, Crandall JR. Experiments for establishing pedestrian-impact lower limb injury criteria. In: Proceedings of the SAE World Congress & Exhibition. March 3-6, 2003; Detroit, MI. Warrendale, PA: Society of Automotive Engineers. SAE 2003-01-0895.
2003	Bhalla K, Bose D, Madeley NJ, Kerrigan J, Crandall J, Longhitano D, Takahashi Y. Evaluation of the response of mechanical pedestrian knee joint impactors in bending and shear loading. In: Proceedings of the 18th International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 19-22, 2003; Nagoya, Japan.
2004	Ivarsson J, Lessley D, Kerrigan J, Bhalla K, Bose D, Crandall J, Kent R. Dynamic response corridors and injury thresholds of the pedestrian lower extremities. In: Proceedings of the 2004 International IRCOBI Conference on the Biomechanics of Impact. September 22-24, 2004; Graz, Austria.179-191.

Cited By (5)

Year	Entry
2013	Zander O, Pastor C, Leßmann P, Gehring D-U. Towards a world-wide harmonized pedestrian legform to vehicle bumper test procedure. In: Proceedings of the 23rd International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 27-30, 2013; Seoul, South Korea.
2015	Zander O, Gehring D-U, van Ratingen M. Beyond safety legislation: contribution of consumer information programmes to enhanced injury mitigation of pedestrians during accidents with motor vehicles. In: Proceedings of the 24th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 8-11, 2015; Gothenburg, Sweden.
2015	Zander O, Wisch M, Gehring D-U. Improvement of the protection of lower extremities of vulnerable road users in the event of a collision with motor vehicles. In: Proceedings of the 24th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 8-11, 2015; Gothenburg, Sweden.
2017	Zander O, Ott J, Wisch M, Fornells A, Fuchs T, Hynd D, Lemmen P, Burleigh M, Lopez-Valdes F, Luera A, Lundgren C. Safety enhanced innovations for older road users (SENIORS): further development of test and assessment procedures towards an improved passive protection of pedestrians and cyclists. In: Proceedings of the 25th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 5-8, 2017; Detroit, MI.
2016	Isshiki T, Konosu A, Takahashi Y. Development and evaluation of the advanced pedestrian legform impactor prototype which can be applicable to all types of vehicles regardless of bumper height: finite element model. In: Proceedings of the 2016 International IRCOBI Conference on the Biomechanics of Injury. September 14-16, 2016; Malaga, Spain.770-784.