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The Q-series of child dummies is a new family of advanced child dummies covering the complete child population up to 12 years. The Q-series' design is not only advanced in terms of its biomechanical basis, it is also developed to be used in both front and side impact making it the first “multi-directional” series of (child) dummies. This paper presents the functional targets for the Q-series, a set of biomechanically based design and performance targets for a 3-year-old dummy and the validation of the prototype version of the 3-year-old Q-dummy, the Q3.

Mathematical modelling is widely used for crash-safety research and design. However, most occupant models used in crash simulations are based on crash dummies and thereby inherit their apparent limitations. Several models simulating parts of the real human body have been published, but only few describe the entire human body and these models were developed and validated only for a limited range of conditions. This paper describes a human body model for both frontal and rearward loading. A combination of modelling techniques is applied using rigid bodies for most body segments, but describing the thorax as a flexible structure. The skin is described in detail using an arbitrary surface. Static and dynamic properties of the articulations have been derived from literature. The RAMSIS anthropometric database has been used to define a model representing a 50th percentile male.

An important requisite for an effective use of numerical tools in occupant safety assessment is that suitable models of crash victims are available. Reliable well validated multibody models of several crash dummies have been developed in the last two decades. Flexible parts are modeled as rigid bodies interconnected by joints that account for the flexibility. Recently the finite element method has been used for modeling such parts. In this paper an alternative method is proposed namely as a flexible body with distributed mass and stiffness. To evaluate these methods, three models of a rib module of a EUROSID-1 dummy are compared with the rib modeled as: a chain of nine rigid bodies interconnected by revolute joints, and torsional springs and dampers, one flexible body with the deformation approximated by one predefined displacement mode, a finite element model using triangular shell elements with a linear elastic material behavior and mass proportional Rayleigh damping.

At the Naval BioDynamics Laboratory (NBDL) in New Orleans a large series of human volunteer experiments has been conducted by Ewing and Thomas [1]* to determine the dynamic head-neck response. From a number of these experiments Wismans et al. [2] determined omni-directional dummy head-neck performance requirements relative to a non-rotated T1 coordinate system (i.e. the head motions incorporate the influence of the thoracic column flexibility). In 1987, the frontal volunteer head-neck response was compared with the response of postmortem human subject (PMHS) experiments [3]. One of the findings was that the volunteer T1 rotations differ significantly from the PMHS T1 rotations which was explained by measurement “errors” in the T1 instrumentation. The present paper is an extension of the previous work [2,3]. A detailed analysis of the high-speed films revealed that the volunteer T1 instrumentation mount was not firmly mounted to the spine.

Ongoing developments in crash safety research, regulations and product enhancements have indicated the need for a review on child dummy design philosophies. Late 1991, the TNO Crash-Safety Research Centre started a research program including a review on child anthropometry, a literature study on biomechanical properties of children and a study on scaling techniques. The objective of this research program is to establish sets of requirements for basic child dummy “design characteristics”. The main design characteristics covered in this paper are anthropometry and biofidelity. The anthropometry study resulted in a new TNO database on child anthropometry and includes published data on more than 75 parameters. The database's background and construction are explained and the main parameters for child dummy design are presented. The literature study on biomechanical properties of children revealed a limited set of data on material properties.