Evaluation of biofidelity of THUMS pedestrian model under a whole-body impact conditions with a generic sedan buck

Abstract

(2017) Evaluation of biofidelity of THUMS pedestrian model under a whole-body impact conditions with a generic sedan buck, Traffic Injury Prevention, 18:sup1, S148-S154, DOI: 10.1080DOI: 10. /15389588.2017 Objective: The goal of this study was to evaluate the biofidelity of the Total Human Model for Safety (THUMS; Ver. 4.01) pedestrian finite element models (PFEM) in a whole-body pedestrian impact condition using a well-characterized generic pedestrian buck model. Methods:The biofidelity of THUMS PFEM was evaluated with respect to data from 3 full-scale postmortem human subject (PMHS) pedestrian impact tests, in which a pedestrian buck laterally struck the subjects using a pedestrian buck at 40 km/h. The pedestrian model was scaled to match the anthropometry of the target subjects and then positioned to match the pre-impact postures of the target subjects based on the 3-dimensional motion tracking data obtained during the experiments. An objective rating method was employed to quantitatively evaluate the correlation between the responses of the models and the PMHS.Injuries in the models were predicted both probabilistically and deterministically using empirical injury risk functions and strain measures, respectively, and compared with those of the target PMHS. Conclusions: Based on the data considered, the THUMS PFEM was considered to be biofidelic for this pedestrian impact condition and vehicle. Given the capability of the model to reproduce biomechanical responses, it shows potential as a valuable tool for developing novel pedestrian safety systems.

A Computational Biomechanics Human Body Model Coupling Finite Element and Multibody Segments for Assessment of Head/Brain Injuries in Car-To-Pedestrian Collisions

“…Three cadaver impact tests from the literature were selected for the validation of the CPCBM [17,48,49]; the details of the PMHSs are listed in Table 1. The subjects were initially positioned in a nominal mid-gait stance with the left foot forward and right foot behind, and were oriented so that they were struck laterally on the subject's right side.…”

“…For each subject, the initial position was adjusted following the positioning guidelines described in SAE J2782. During the test, the impact buck was accelerated to a target impact velocity of approximate 40 km/h, at which it contacted the pedestrian [17]. According to Wu et al [17], a large amount of motion information from the head to the lower extremities of the subjects was recorded from the tests, including various anatomical positions (head, thoracic T1 and T8, pelvis, left and right femur, etc.).…”

“…During the test, the impact buck was accelerated to a target impact velocity of approximate 40 km/h, at which it contacted the pedestrian [17]. According to Wu et al [17], a large amount of motion information from the head to the lower extremities of the subjects was recorded from the tests, including various anatomical positions (head, thoracic T1 and T8, pelvis, left and right femur, etc.). Since the attention of our study focused on the head responses of the CPCBM, only the subject's head-related experimental data (including trajectory, displacement, velocity, acceleration) was used for the validation work.…”

“…Here, the objective rating tool correlation and analysis CORA [52] was used to quantitatively evaluate the correlation of the analyzed head response signals between the predictions of both the adjusted TNO model and the CPCBM, and tested PMHSs [17]; such a method has been used in similar studies [53,54]. The objective rating tool CORA uses two independent sub-ratings: a corridor rating and cross-correlation rating to assess the correlation of two signals.…”

“…The head-neck part and the rest of the CPCBM are taken from THUMS (Version 4.01) FE and TNO (Version 7.5) MB 50th percentile adult male pedestrian models; each part being connected by the coupling technique [46,47]. The reliability of the CPCBM is evaluated by reconstructing three cadaver tests published in the literature [17,48,49]. This study can provide a more efficient and reliable tool for the research of pedestrian head-injury biomechanics and prevention of injury due to car impact.…”