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According to accident analysis, submarining is responsible for most of the frontal car crash AIS 3+ abdominal injuries sustained by restrained occupants. Submarining is characterized by an initial position of the lap belt on the iliac spine. During the crash, the pelvis slips under the lap belt which loads the abdomen. The order of magnitude of the abdominal deflection rate was reported by Uriot to be approximately 4 m/s. In addition, the use of active restraint devices such as pretensioners in recent cars lead to the need for the investigation of Out-Of-Position injuries. OOP is defined by an initial position of the lap belt on the abdomen instead of the pelvis resulting in a direct loading of the abdomen during pretensioning and the crash. In that case, the penetration speed of the belt into the abdomen was reported by Trosseille to be approximately 8 to 12 m/s. The aim of this study was to characterize the response of the human abdomen in submarining and OOP.

This paper presents a pilot study aimed to carry out a method for prehension movement recording. This method consists of using, simultaneously, a motion analysis system (Vicon®) and a sensitive glove (Cyber Glove®). The objective is to be able to give a set of complete data to our hand model in order to simulate the human prehension movement. In a first study, only a data glove was used to record grasping movement. Many problems appeared when analysing the output of this system: 1. the hand model considered in the glove software is different from our model, 2. the arch degree of freedom does not exist in the glove model, despite the existence of the corresponding sensor, 3. the output from ab duction and flexion sensors are linked, 4. the calibration of the thumb is not efficient. From these technical constraints, another movement recording system - motion analysis system - is used and data glove completes the data recorded with motion analysis system.

The Body Segments Inertial Parameters (BSIPs) are essential data in biomechanics. However, the measurements on cadaver are restrictive and the measurements on living human remain limiting. Moreover, in the literature, the predictive equations are mainly 2D and include two restraining assumptions. Accordingly, it is still challenging to obtain appropriate 3D BSIPs. A bi-planar radiographic method, previously developed to obtain personalized BSIPs, and adjusted scaling equations, recently developed to provide the 3D position of the center of mass and both moments and products of inertia, were compared and demonstrated the same mass distribution (although significant differences). The center of mass was slightly posterior and lateral, and the products of inertia were almost of the same order as the longitudinal moment of inertia. These data may be useful for researchers who would like to obtain appropriate 3D BSIPs.

An experiment was designed to observe balance recovery movement of standing volunteers in public transportation situations, and attempt to predict it. A perturbation corresponding to a typical emergency breaking situation was applied to the platform on which the subjects were standing. The effect of three different postures, three acceleration profiles and two external constraints were studied. Movements were reconstructed using a three dimensional whole body kinematic model. The reconstructed kinematic data were reduced prior to the movement analysis. The simplified representation obtained showed that the balance recovery movement consists of a succession of four basic phases, and also allowed to highlight the influence of the experimental parameters. In order to evaluate whether the data generated can be used to predict the motion in arbitrary conditions, the response of the intermediate acceleration level tests was predicted by interpolation between the two extreme conditions.

This panel provided a forum for discussion of future research and development desired by users and potential users of DHM technologies. The discussion was based on the experiences of users from various sectors and industries. Panelists provided written statements and delivered short presentations prior to opening the session to audience discussion. The panel was designed to inform and drive research and development plans to fill these needs.

Numerical models are used more and more to visualize a human operator within a work environment and simulate his movements. Many models are limited in their ability to simulate complex activities like prehension and objects manipulation. The hand models proposed in the literature are relatively simple, especially assuming the palm as a rigid body, which leads to unrealistic representations of complex attitudes. The objective of the present study is to develop a more advanced hand model, able to properly simulate prehension postures. A 25 degrees of freedom (DOF) hand model has been proposed including 2 DOF for representing the palm arch. Compared to the model without palm arch, the proposed model has made significant improvement of the hand posture representation, suggesting the need of including palm arch for simulating complex hand grasping attitudes.

Improvement in the accessibility assessment of the seatbelts using a Digital Human Model requires a precise description of driver belt donning movement and of the associated discomfort. In order for automotive designers to be able to simulate seatbelt reaching movement, a general approach of motion simulation for complex and specific tasks has been proposed in this paper. It consists of three steps: constitution of a structured database, selection of an appropriate movement and its adaptation to meet new constraints. From an experiment, a database of 644 movements of automotive seatbelt reaching movements has been built-up. In order to structure the database, the temporal and spatial characteristics of the trajectories of main markers (e.g. markers attached to the hand and the torso) as well as joint movements were analysed, allowing us to identify motion control strategies.

Most of the thoracic injury criteria proposed these past years are based mainly on the analysis of data obtained from experiments with human cadavers and are related principally to rib fractures. And yet, the actual threat to life incurred in real accidents results from lesions to intrathoracic viscerae that are not necessarily correlated with the number of rib fractures. Moreover, the injuries sustained by cadavers during experiments are mainly rib fractures. In these cases, visceral lesions are unusual and not necessarily identical with those sustained by real accident victims. Preliminary results of measurements concerning rib strength and dynamic behavior of the cadaver thorax in frontal impacts show the rib cage offers a low resistance against compression and the vertebral column acts as a stop. The combination of these various data leads to questioning the validity of thoracic injury criteria based on the number of rib fractures observed on human cadavers.