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The strain rate behavior of mild-steel and high-strength steel qualities has been investigated. The hardening as a function of the strain rate of a set of steel qualities was determined, and it was found that the gain in strength for high-strength steels is not in proportion to the static yield-strength. The absolute increase in strength for high-strength steel is often less than for mild steel (although this fact depends on the microstructure of the steel). This fact is reflected in the absorption of energy for square crash-columns that were tested on a sled-impact facility. Downgauging parts from mild-steel to high-strength steel must be therefore be done carefully to maintain its crashworthiness properties. Special attention should be given to the strain rate sensitivity of the next generation of high strength steel qualities. Moreover we have tested and simulated spotwelded columns to test the failure criterion for spotwelds.

This paper concerns the development and validation of a three-dimensional mathematical model representing a motorcycle with rider. As part of this development, several motorcycle to barrier tests were performed at the laboratories of the TNO Crash-Safety Research Centre and several measurements were carried out, including measurements to determine the inertia properties of the motorcycle segments. Results of two full scale tests involving a passenger car were then applied to validate the model in a more realistic crash environment. The resulting MADYMO motorcycle model consists of 7 bodies linked to each other by joints and spring-damper type elements. Special attention was given to the mathematical representation of front fork, front wheel and gastank. A 50th %ile Part 572 dummy with pedestrian pelvis and legs represented the rider. For representation in the model an existing dummy database was updated.

MADYMO is a well accepted multibody program for crash analyses. The main emphasis of the program is the prediction of the kinematics and dynamic behaviour of crash victims during a crash. A brief description of the MADYMO history and theory is presented as well as recently developed couplings with explicit finite element programs for non-linear structural analyses. The development of dummy databases is described with special emphasis on the development of the EUROSID dummy database using a new multibody module. This module is based on a recursive algorithm and allows modelling of other kinematic joints in addition to the currently available ball and socket joints. The use of MADYMO in impact biomechanics is illustrated with examples from the area of vehicle safety and sports biomechanics. The use of MADYMO for structural modelling is illustrated by a side-impact simulation using MADYMO to model both car and occupant.

This paper presents a measurement program of a sitting 50th percentile Hybrid III Dummy to determine a database for computer simulations. Geometrical, inertial, joint property and surface compliance measurements have been carried out. A description of the measuring methodology is given. On the basis of these measurements a 20 segment database for the MADYMO 3D occupant simulation program is developed. The major advancements of this database compared to an earlier 15-segment database developed by TNO [1]* can de summarized as follows: Five additional segments are incorporated in this database to account for the hands, the shoulders(clavicles) and the sternum. The database includes a complete omni-directional description for the neck as well as the lumbar spine. A detailed mathematical surface description is available, for instance to be used for computer animations. Segment ellipsoids for contact interactions have been determined in a more accurate way.

MADYMO is a computer program package for the simulation of two- or three-dimensional human body gross motions. Recently a two-dimensional airbag model has become available for MADYMO 2D. The airbag is represented in the model by a non-deformable ellipsoid or elliptical cylinder. Standard MADYMO features can be used in conjunction with the airbag model. This allows e.g. the simulation of belted occupants, inclusion of a separate sternum element in the thorax and connection of the airbag to a flexible steering column. Both driver and passenger side airbags can be simulated. The airbag contact algorithms have been validated on the basis of dynamical impact tests on an airtight driver bag, with various impactor shapes and impact velocities. In addition sled tests and full scale crash tests have been simulated. In this paper a description of the airbag model theory will be presented, particularly with respect to the penetration volume and contact force calculations.