Modal analysis of the human neck in vivo as a criterion for crash test dummy evaluation

Abstract Low speed rear impact remains an acute automative safety problem because of a lack of knowledge of the mechanical behaviour of the human neck early after impact. Poorly validated mathematical models of the human neck or crash test dummy necks make it difficult to optimize automotive seats and head rests. In this study we have constructed an experimental and theoretical modal analysis of the human head–neck system in the sagittal plane. The method has allowed us to identify the mechanical properties of the neck and to validate a mathematical model in the frequency domain. The extracted modal characteristics consist of a first natural frequency at 1.3±0.1 Hz associated with head flexion-extension motion and a second mode at 8±0.7 Hz associated with antero-posterior translation of the head, also called retraction motion. Based on this new validation parameters we have been able to compare the human and crash test dummy frequency response functions and to evaluate their biofidelity. Three head–neck systems of current test dummies dedicated for use in rear-end car crash accident investigations have been evaluated in the frequency domain. We did not consider any to be acceptable, either because of excessive rigidity of their flexion-extension mode or because they poorly reproduce the head translation mode. In addition to dummy evaluation, this study provides new insight into injury mechanisms when a given natural frequency can be linked to a specific neck deformation.

[1]  C. E. Clauser,et al.  Weight, volume, and center of mass of segments of the human body , 1969 .

[2]  Mats Y. Svensson,et al.  A COMPARISON BETWEEN VOLUNTEER, BIORID P3 AND HYBRID III PERFORMANCE IN REAR IMPACTS , 1999 .

[3]  Felix H. Walz,et al.  BIOMECHANICAL ASPECTS OF CERVICAL SPINE INJURIES , 1995 .

[4]  M Y Svensson,et al.  The influence of seat-back and head-restraint properties on the head-neck motion during rear-impact. , 1996, Accident; analysis and prevention.

[5]  Claude Tarriere,et al.  DEVELOPMENT OF A FINITE ELEMENT MODEL OF THE NECK , 1994 .

[6]  D. J. Ewins,et al.  Modal Testing: Theory and Practice , 1984 .

[7]  B S Myers,et al.  Inertial properties and loading rates affect buckling modes and injury mechanisms in the cervical spine. , 2000, Journal of biomechanics.

[8]  N Yoganandan,et al.  Biomechanics of the cervical spine Part 3: minor injuries. , 2001, Clinical Biomechanics.

[9]  Arno Eichberger,et al.  COMPARISON OF DIFFERENT CAR SEATS REGARDING HEAD-NECK KINEMATICS OF VOLUNTEERS DURING REAR END IMPACT , 1997 .

[10]  H. Saunders.  Literature Review : RANDOM DATA: ANALYSIS AND MEASUREMENT PROCEDURES J. S. Bendat and A.G. Piersol Wiley-Interscience, New York, N. Y. (1971) , 1974 .

[11]  W Goldsmith,et al.  Response of a human head/neck/upper-torso replica to dynamic loading--II. Analytical/numerical model. , 1987, Journal of biomechanics.

[12]  Naoki Okano,et al.  AN EVALUATION OF PROTOTYPE SEATS USING BIORID-P3 AND HYBRID III WITH TRID NECK , 2000 .

[13]  R L Stalnaker,et al.  Driving point impedance characteristics of the head. , 1971, Journal of biomechanics.

[14]  C. E. Clauser,et al.  Anthropometric Relationships of Body and Body Segment Moments of Inertia , 1980 .

[15]  R. P. Howard,et al.  Analysis of Human Test Subject Kinematic Responses to Low Velocity Rear End Impacts , 1993 .

[16]  M. J. Wolanin,et al.  HYBRID III - A BIOMECHANICALLY-BASED CRASH TEST DUMMY , 1977 .

[17]  Michael Kleinberger,et al.  Application of Finite Element Techniques to the Study of Cervical Spine Mechanics , 1993 .

[18]  Priya Prasad,et al.  BIOFIDELITY OF ANTHROPOMORPHIC TEST DEVICES FOR REAR IMPACT , 1997 .

[19]  de Mkj Marko Jager,et al.  Mathematical head-neck models for acceleration impacts , 1996 .

[20]  William H. Muzzy,et al.  Comparison of Human and Hybrid III Head and Neck Dynamic Response , 1986 .

[21]  Jac Wismans,et al.  Development and evaluation of a new rear-impact crash dummy: the RID2 , 2001 .

[22]  John B. Bomar,et al.  Comparison of Human and ATD Head Kinematics During Low-Speed Rearend Impacts , 1993 .

[23]  Rolf H. Eppinger,et al.  Biomechanical response of human cervical spine to direct loading of the head , 2001 .

[24]  J B Welcher,et al.  Influence of Seat Foam and Geometrical Properties on BioRID P3 Kinematic Response to Rear Impacts , 2003, Traffic injury prevention.

[25]  E. G. Janssen,et al.  A DUMMY NECK FOR LOW SEVERITY REAR IMPACTS , 1996 .

[26]  Koshiro Ono,et al.  Motion Analysis of Human Cervical Vertebrae During Low-Speed Rear Impacts by the Simulated Sled , 1999 .

[27]  D H Robbins,et al.  Parameter Study of Biomechanical Quantities in Analytical Neck Models , 1972 .

[28]  Y C Deng,et al.  Anthropomorphic dummy neck modeling and injury considerations. , 1989, Accident; analysis and prevention.

[29]  T. Asazuma,et al.  X-ray study of the human neck motion due to head inertia loading , 1994 .

[30]  Johan Davidsson,et al.  BioRID P3: design and performance compared to Hybrid III and volunteers in rear impacts at deltaV=7 km/h , 1999 .

[31]  Claes Tingvall,et al.  Prediction of neck injuries in rear impacts based on accident data and simulations , 1997 .

[32]  E. H. Harris,et al.  Mass, Volume, Center of Mass, and Mass Moment of Inertia of Head and Head and Neck of Human Body , 1973 .

[33]  G. Siegmund,et al.  Kinetic and Kinematic Responses of the RID2a, Hybrid III and Human Volunteers in Low-Speed Rear-End Collisions. , 2001, Stapp car crash journal.

[34]  Mats Y. Svensson.  REAR-END COLLISIONS. DEVELOPMENT AND VALIDATION OF A NEW DUMMY- NECK , 1992 .

[35]  T. Szabo,et al.  Human Subject Kinematics and Electromyographic Activity During Low Speed Rear Impacts , 1996 .

[36]  M. Griffin,et al.  Resonance behaviour of the seated human body and effects of posture. , 1997, Journal of biomechanics.

[37]  Golinski Wz.  Three-dimensional dynamic modelling of the human cervical spine in whiplash situations. , 2000 .

[38]  H. J. Woltring,et al.  Omni-Directional Human Head-Neck Response , 1986 .