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Injuries to the thorax in frontal impact accidents remain an important problem even for restrained occupants. During a frontal accident a significant portion of the forces restraining the occupant pass through the thoracic belt and deform the chest with the possibility of serious thoracic injuries. It is therefore important to understand the deformation of the human thorax when loaded by a thoracic belt and to understand how accurately crash dummies used in standard tests reproduce these deformations. This paper describes results of 19 tests in which a diagonal shoulder belt dynamically loaded the thorax of unembalmed cadavers and dummies (1). In all the tests, thoracic external deformations were measured using string potentiometers and two External Peripheral Instrument for Deformation Measurement (EPIDM) transducers (2).

In occupant safety simulations it is desirable to extend existing rigid body occupant models towards deformable Finite Element models. Thereby a wider range of occupant / structure interactions can be covered and a better accuracy can be achieved. This paper describes some aspects of the FE modelling of the EUROSID thorax for use in an explicit Finite Element code. First a single rib model is evaluated, then a full thorax is generated and inserted into a rigid body Dummy model. Experimental results from impactor tests serve as a basis for the validation of the model.

To estimate the behaviour of the thorax of the human cadaver and Hybrid III a total of 33 belt impact tests were performed with the two surrogates. These tests have shown that the Hybrid III thorax is stiffer than that of the cadaver and that the internal thoracic deflection transducer may not necessarily record the maximum thoracic deflection. The belt load was lower value with the cadavers, which confirms the differences in stiffness. A belt force of 10 KN in the cadaver tests was associated with an average of 6 rib fractures. If we consider the relationship between the thoracic deflection and the number of rib fracture cadavers showing 5 or more rib fractures sustained an external thoracic deflection at least of 7.5 cm measured at the mid sternum. The analysis of V*C parameter indicates an average V*C value of 0.77 for 6 rib fractures, and the values of V*C measured on Hybrid III are sligthly lower than those of cadaver tests.

Improvement of pedestrian safety is considered a priority in crash injury protection. Dummies, however, are not able to give a humanlike and repeatable impact response in pedestrian tests. The Biomechanical Laboratory of ONSER in France and the Department of Traffic Safety of Chalmers University in Götheborg, Sweden have designed a new dummy for pedestrian testing. The dummy is designed according to the latest available anthropometric and biomechanical data. Its symmetry around the vertical axis allows repeatability for the kinematic and injury parameters. It allows a measurement of uncommon biomechanical parameters related to injury mechanisms. Its leg is instrumented to determine the distribution of forces and momenta applied to the leg.

During the phase IV of the EEC biomechanical programme, the available side impact dummies were evaluated and this work concluded that none of the dummy was acceptable. The European Experimental Vehicle Committee set up a working group to built a new side impact dummy to be used in a standard side impact test. The ONSER laboratory was in charge of the development of the pelvis. This paper includes the specifications for the pelvis, agreed by the EEVC working group dealing with this subject, anthropometric analysis to choose sizes and mass distribution a description of the shape of the pelvic bone and the location and the type of transducer (force, acceleration). The design of the hip joint and the use of deformable materials to simulate the pelvic bone deformations are discussed. Results of impactor tests using a dummy fitted with this pelvis are analyzed and their results compared to those of cadavers tests conducted previously.