Concept design of a 4-DOF pedestrian legform

Zhou, Qing; Quade, Michael; Du, Huiliang

Affiliations

¹State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China

Abstract

The new European car-to-pedestrian impact safety protection regulation has prompted many research efforts in this area. For knee and lower leg protection, the current regulation requires using a legform that consists of 2 degrees-of-freedom (DOF) for injury assessment. It mimics the shear and bending about the knee joint when the lateral side of a pedestrian is impacted by a vehicle. However, in a smaller portion, non-lateral impact accidents also exist in the real world. Moreover, even in a purely lateral impact, once the legform contacts with the bumper, it could rotate towards the other directions due to the curvatures of the bumper shape and the deformation of the bumper foam, causing the legform taking load from other directions. For assessing injuries under omni-direction impact, a concept design of a 4-DOF pedestrian legform is developed. The two added DOFs represent the natural human knee rotation and the shear with respect to the knee joint when a pedestrian is impacted from the front or the back. The bio-mechanical requirements of the 4-DOF legform are adopted from the existing 2-DOF pedestrian legform and the Hybrid III dummy knee. The challenge is to design all the 4-DOF mechanisms, including the motion and stiffness mechanisms, in a limited space of the legform. Design methodology is also documented in this paper.

Links

URL: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv20/07-0196-W.pdf

Cited Works (6)

Year	Entry
2001	Traffic Safety Facts 2000: Pedestrians. Washington, DC: U.S. Dept of Transportation, National Center for Statistics and Analysis, National Highway Traffic Safety Administration; 2001. Report No. DOT HS 809 331.
1998	EEVC Working Group 17 Report: Improved Test Methods to Evaluate Pedestrian Protection Afforded by Passenger Cars. European Enhanced Vehicle-Safety Committee (EEVC); 1998.
2003	Kuehn M, Froeming R, Schindler V. An advanced testing procedure for the pedestrian-car-collision. In: Proceedings of the 18th International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 19-22, 2003; Nagoya, Japan.
1978	Viano DC, Culver CC, Haut RC, Melvin JW, Bender M, Culver RH, Levine RS. Bolster impacts to the knee and tibia of human cadavers and an anthropomorphic dummy. In: Proceedings of the 22nd Stapp Car Crash Conference. October 24-26, 1978; Ann Arobor, MI. Warrendale, PA: Society of Automotive Engineers:403-428. SAE 780896.
2004	Bose D, Bhalla K, Rooij L, Millington S, Studley A, Crandall J. Response of the knee joint to the pedestrian impact loading environment. In: Proceedings of the SAE World Congress & Exhibition. March 8-11, 2004; Detroit, MI. Warrendale, PA: Society of Automotive Engineers. SAE 2004-01-1608.
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.