Different factors influencing post-crash pedestrian kinematics

Pedestrian crashes are the most frequent cause of traffic-related fatalities worldwide. The high number of pedestrian accidents justifies more active research work on passive and active safety technology intended to mitigate pedestrian injuries. Post-impact pedestrian kinematics is complex and depends on various factors such as impact speed, height of the pedestrian, front-end profile of the striking vehicle and pedestrian posture, among others. The aim of this study is to investigate the main factors that determine post-crash pedestrian kinematics. The injury mechanism is also discussed. A detailed study of NASS-PCDS (National Automotive Sampling System - Pedestrian Crash Data Study, US, 1994-1998), showed that the vehicle-pedestrian interaction in frontal crashes can be categorized into four types: "Thrown forward", "Wrapped position", "Slid to windshield" and "Passed over vehicle". A Principal Component Analysis (PCA) was performed and 11 independent factors were identified for study from a set of 26 variables, as defined in NASS-PCDS. Pedestrian-vehicle size ratio and the impact speed are the two most influential factors that determine post crash pedestrian kinematics. However, the standing posture of a taller pedestrian can also cause rotational movement around the local Z axis, leading to a face-up/down mode of head-face impact before falling on the hood. The findings from the NASS-PCDS study were also confirmed and verified with the help of numerical simulations performed using two modified JAMA human FE models. An adult model (male, 175cm and 72kg) and a properly scaled child model (6 years old, 120cm and 21kg) were effectively utilized to investigate the post-crash kinematics in different conditions. Language: en

[1]  Jeffrey Richard Crandall,et al.  A Multi-Body Computational Study of the Kinematic and Injury Response of a Pedestrian with Variable Stance upon Impact with a Vehicle , 2004 .

[2]  King H. Yang,et al.  A proposed injury threshold for mild traumatic brain injury. , 2004, Journal of biomechanical engineering.

[3]  Susumu Ejima,et al.  MODIFICATION AND VALIDATION OF HUMAN NECK MODEL UNDER DIRECT HEAD LOADING , 2003 .

[4]  Jason Stammen,et al.  Pedestrian head impact testing and PCDS reconstructions , 2001 .

[5]  Francisco J. López-Valdés,et al.  Pedestrian collisions with flat-fronted vehicles: injury patterns and importance of rotational accelerations as a predictor for traumatic brain injury (TBI) , 2009 .

[6]  Caroline Deck,et al.  Influence of rotational acceleration on intracranial mechanical parameters under accidental circumstances , 2007 .

[7]  Michelle F. Heller,et al.  Using National Databases to Evaluate Injury Patterns in Pedestrian Impacts , 2009 .

[8]  K L Jarrett.  Pedestrian injury: analysis of the PCDS field collision data , 1998 .

[9]  Chip Chidester,et al.  Pedestrian crash data study: an interim evaluation , 1996 .

[10]  Thierry Serre,et al.  Child pedestrian anthropometry: evaluation of potential impact points during a crash. , 2010, Accident; analysis and prevention.

[11]  Dennis A. Guenther,et al.  A Demographic Analysis and Reconstruction of Selected Cases from the Pedestrian Crash Data Study , 2002 .

[12]  Jeffrey Richard Crandall,et al.  Lateral Injury Criteria for the 6-year-old Pedestrian - Part I: Criteria for the Head, Neck, Thorax, Abdomen and Pelvis , 2004 .

[13]  Jeffrey Richard Crandall,et al.  The Causes of Head Injury in Vehicle-Pedestrian Impacts: Comparing the Relative Danger of Vehicle and Road Surface , 2006 .

[14]  R A Isenberg.  UPDATE ON THE PEDESTRIAN CRASH DATA STUDY , 1998 .

[15]  Yasuhiro Dokko,et al.  Validation of the human head fe model against pedestrian accident and its tentative application to the examination of the existing tolerance curve , 2003 .

[16]  Jeffrey Richard Crandall,et al.  Influence of vehicle body type on pedestrian injury distribution , 2005 .

[17]  Jeffrey Richard Crandall,et al.  Lateral Injury Criteria for the 6-year-old Pedestrian - Part II: Criteria for the Upper and Lower Extremities , 2004 .

[18]  Jason R. Kerrigan,et al.  Investigating Pedestrian Kinematics with the Polar-II Finite Element Model , 2007 .

[19]  Susumu Ejima,et al.  Biomechanical responses of head/neck/torso to lateral impact loading on shoulders of male and female volunteers , 2005 .

[20]  Dominique Cesari,et al.  Pedestrian-Vehicle Accident: Analysis of 4 Full Scale Tests with PMHS , 2007 .

[21]  Harold J. Mertz,et al.  The Position of the United States Delegation to the ISO Working Group 6 on the Use of HIC in the Automotive Environment , 1985 .

[22]  Christophe Bastien,et al.  Computer simulation of real-world vehicle–pedestrian impacts , 2011 .

[23]  Michelle F. Heller,et al.  Age Effects on Injury Patterns in Pedestrian Crashes , 2010 .

[24]  Jeffrey Richard Crandall,et al.  A Comparative Evaluation of Pedestrian Kinematics and Injury Prediction for Adults and Children upon Impact with a Passenger Car , 2004 .

[25]  Yutaka Okamoto,et al.  Pedestrian Head Impact Conditions Depending on the Vehicle Front Shape and Its Construction--Full Model Simulation , 2003, Traffic injury prevention.

[26]  Jeffrey Richard Crandall,et al.  A REVIEW OF PEDIATRIC PEDESTRIAN INJURIES AT A LEVEL 1 TRAUMA CENTER , 2003 .

[27]  Hamid M. Lankarani,et al.  Evaluation of the kinematics and injury potential to different sizes of pedestrians impacted by a utility vehicle with a frontal guard , 2011 .

[28]  Paul Scullion,et al.  Injury risk to specific body regions of pedestrians in frontal vehicle crashes modeled by empirical, in-depth accident data. , 2010, Stapp car crash journal.

[29]  Jeffrey Richard Crandall,et al.  PEDESTRIAN CRASH RECONSTRUCTION USING MULTI-BODY MODELING WITH GEOMETRICALLY DETAILED, VALIDATED VEHICLE MODELS AND ADVANCED PEDESTRIAN INJURY CRITERIA , 2003 .

[30]  Jason R. Kerrigan,et al.  Kinematic Analysis of Head/Neck Motion in Pedestrian-Vehicle Collisions Using 6-Degree-of-Freedom Instrumentation Cubes , 2006 .

[31]  Yukou Takahashi,et al.  Validation of an FE Lower Limb Model for a Child Pedestrian by Means of Accident Reconstruction , 2008 .

[32]  Jeffrey Richard Crandall,et al.  Pedestrian Kinematics Investigation with Finite Element Dummy Models Based on AnthropometryScaling Method , 2007 .

[33]  Koichi Kamiji,et al.  The clarification of individual injury mechanism difference in pedestrian FE model utilizing cadaver scaling and posturing techniques , 2011 .