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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 concerns the computer modelling of airbag restraint systems, particularly the aspect of contact interaction between the human body and the airbag. Two approaches can be distinguished for modelling the airbag. The earliest models use a non-deformable elliptical shape or a deformable shape based on line segments and circular arcs for representation of the airbag. Penetration volumes and contact forces are calculated in an empirical manner. A second approach uses the finite element method to simulate the bag material. The finite element bag can deform realistically and bag inertia forces are generated. In this paper a comparison is made between simulation results obtained with the empirical airbag model in MADYMO 2D and the finite element airbag model in PISCES. Validation for both types of simulation has been carried out using impactor tests on sealed airbags. Parameters varied in these impactor tests include the impact velocity and the shape of the impactor face.

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.