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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.

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.

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.

The three-dimensional head-neck model of Deng and Goldsmith (J. Biomech., 1987) was adapted and implemented in the integrated multibody/finite element code MADYMO. The model comprises rigid head and vertebrae, connected by linear viscoelastic intervertebral joints and nonlinear elastic muscle elements. It was elaborately validated by comparing model responses with the responses of human volunteers subjected to frontal and lateral sled acceleration impacts. Fair agreement was found for both impacts. Further, a sensitivity analysis was performed to assess the effect of parameter variations on model response. The model proved satisfactory and may be used as a tool to improve restraint systems or dummy necks.

Two mathematical head-neck models have been developed using MADYMO: a global model and a detailed one. The global model comprises rigid head and vertebrae connected through nonlinear viscoelastic intervertebral joints representing the lumped behaviour of disc, ligaments, facet joints and muscles. The model response to frontal impacts agreed reasonably with volunteer responses. The detailed model comprises rigid head and vertebrae connected through linear viscoelastic discs, nonlinear viscoelastic ligaments, frictionless facet joints and contractile muscles. The model response to lateral impacts agreed excellently with volunteer responses, whereas the response to frontal impacts showed that the model was too flexible. The global model is especially suited for use in complex simulations as occupant behaviour in car crashes, whereas the detailed model is particularly suited for neck injury assessment.

Two child restraint system sled tests with a child cadaver* and a 3-year old child dummy have been carried out at the Highway Safety Research Institute of The University of Michigan. Some differences between the kinematical response of dummy and cadaver were found. Two mathematical models have been formulated, using the MADYMO program package, for the special purpose of evaluating child restraint performance. A description of the validated dummy and cadaver model is presented together with a comparison of experimental and model results. A sensitivity study was conducted to have a better insight into the effects of various parameters on the child's response. To show the use of the model as a design tool, a simulation with an energy absorbing backstrap is presented. It is concluded that the mathematical model is a better simulation for the cadaver kinematics than the dummy.

This paper presents a three-dimensional 15-segment model of the Hybrid III dummy for the MADYMO 3D Crash Victim Simulation program. The model is based on measurements conducted on two Hybrid III dummies by Wright Patterson Air Force Base. Results of MADYMO 3D simulations will be compared with Hybrid III sled tests conducted by Ford Motor Co. These tests were conducted at three different impact severity levels. For the three test conditions good agreement between model and experimental results could be observed for most of the output parameters. Recommendations for further model improvements will be made.

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.

Mathematical modelling of the human body is widely used for automotive crash-safety research and design. Simulations have contributed to a reduction of injury numbers by optimisation of vehicle structures and restraint systems. Currently such simulations are largely performed using occupant models based on crash-dummies. These models inherit the apparent differences between dummies and the real human body. Furthermore, crash-dummies are only available for a limited set of body sizes. In order to assess passive safety for different body sizes, a method has been developed to generate models representing subjects of varying anthropometry. This method has been applied to “scale” crash-dummy models towards different body sizes and proportions. As a next step, models of the real human body for impact loading have been developed. A combination of modelling techniques is applied using rigid bodies for most body segments, but describing the thorax as a flexible structure.