Development of a Parametric Vehicle Front Structure Model for Pedestrian Impact Simulations
In this study, a simplified, parametric vehicle front structure was proposed to represent the real vehicle when impacted with full-scale finite element pedestrian human body model (HBM). To capture the real impact responses of human lower limbs, the real
- PDF / 1,051,908 Bytes
- 15 Pages / 439.37 x 666.142 pts Page_size
- 70 Downloads / 182 Views
Abstract In this study, a simplified, parametric vehicle front structure was proposed to represent the real vehicle when impacted with full-scale finite element pedestrian human body model (HBM). To capture the real impact responses of human lower limbs, the real vehicle energy-absorbing structures were modeled using distributed beam elements and deformable shell elements to replicate the contact characteristics between vehicle and HBM. An investigation of vehicle front-end profile characteristics in worldwide popular sedan models was conducted to determine the ranges of geometry variables. A local stiffness measurement approach is also proposed. The simplified model is further validated using a detailed sedan model, and the impact responses of HBM in the two simulations correlate quite well with each other. Therefore it can be further used in the DOE study or optimization work in the vehicle front structure design for pedestrian lower limb impact protection.
Keywords Vehicle front structure Simplified parametric model mation Human body model (HBM) Pedestrian impact
Local defor-
F2012-F03-004 B. Nie (&) J. Huang Y. Xia Q. Zhou State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing, China B. Deng M. Neal General Motors Global Research and Development, Warren, MI, USA
SAE-China and FISITA (eds.), Proceedings of the FISITA 2012 World Automotive Congress, Lecture Notes in Electrical Engineering 197, DOI: 10.1007/978-3-642-33805-2_24, Ó Springer-Verlag Berlin Heidelberg 2013
295
296
B. Nie et al.
1 Introduction In car-pedestrian impacts, the lower limbs and head are the most frequently injured body parts [1, 2]. The statistics indicate that 80 % of all pedestrians involved in car-to-pedestrian accidents sustained knee injuries [3]. In regulatory tests, legform impactors such as the TRL and Flex legforms were proposed to evaluate lower limb injuries of pedestrians when laterally impacted with a vehicle [4, 5]. Simplified vehicle front-end models are widely utilized in pedestrian impact analysis, including both FE based models and multi-body models. Due to the high computational efficiency and flexibility of adjusting geometry and stiffness variables, the simplified models could be used in algorithm-based optimization design [6, 7]. Technical flow of parameter analysis for pedestrian lower limb protection has been mentioned in the literature [8–10], including determination of the design variables, Design of Experiments (DOE) study and response surface of the objective function. Therefore a validated parametric vehicle model is an important basis. Existing simplified models are usually designed for lower legform impactors. These subsystem impactors are usually designed in an over-simplified way to meet the repeatability and reusability requirements. Since the legform impactors do not include the upper body parts, the kinematic responses of the legform impactors are different from those of a full-scale human body [11, 12]. In order
Data Loading...
