Projects / Programmes
Modelling of anatomical structures for analysis of occupant loads and injuries in traffic accidents
| Code |
Science |
Field |
Subfield |
| 2.11.01 |
Engineering sciences and technologies |
Mechanical design |
Basic and system know-how |
| Code |
Science |
Field |
| T115 |
Technological sciences |
Medical technology |
| B115 |
Biomedical sciences |
Biomechanics, cybernetics |
traffic accident analyses, biomechanics, numerical modelling
Researchers (14)
Organisations (3)
Abstract
The project proposal considers human body mathematical modelling. The aim of the project is further development of a human body model, purposed for analysis of loads and injuries of occupants in traffic accidents. The model, based on the multibody dynamics principles, will be modified using mathematical formulation that ensures better numerical efficiency and stability. The passive human body model will be improved with a muscle model, thus enabling analysis of the muscle activity influence on the occupant dynamic response in vehicle collisions. Theoretical and experimental methods for detailed human body modelling will be applied in cervical spine modelling. The use of finite element method in modelling the cervical spine demands establishing proper data about tissue material properties. Due to the limited applicability of the published data, a facility is needed for testing cervical spine dynamical response, together with the modification of the existing sled test facility. The experimental data will represent the basis for validation and optimisation of the human body model developed. It is expected that the proposed project will improve the knowledge of injury mechanisms and the reliability in estimating the loads and injuries of the occupants in traffic and other accidents.
Significance for science
The content of the project helps enhance and expand the knowledge on the injuries of traffic accident participants, especially in the event of a whiplash associated disorder. The project includes significant factors associated with the occurrence of traffic accidents and characterisation of the exposed anatomic structures.
A detailed examination of the literature and our own research findings enabled identification of key problems in human body modelling for traffic accident analysis. The examination proved inconsistency and unreliability of the available data on mechanical properties of anatomic structures. The effect of deformation velocity and tissue sample preparation on the measured mechanical properties has not been determined yet. Furthermore, there are no standard procedures to determine them. These shortcomings decrease the useful value of commercial software which enables human body modelling in the event of collision.
Within the framework of the project, new methodology for systematic determination of mechanical properties of anatomic structures was developed. A test rig was set up for measuring soft tissue behaviour under vehicle collision conditions with computer supervision of all relevant factors.
The developed hardware and software enable simulation of various time courses of tissue loads which can occur under vehicle collision conditions. The system sensory equipment helps observe the occurrence of soft tissue injuries, while the lower injury limit can be determined by means of histological examination. We rectified the problems which occur during the geometrical modelling of anatomic structures for various fields of work, such as biomechanics and simulation of surgical procedures. Complicated forms and coincidental variability locally increase the number of finite elements and thereby prolong the CPU time and decrease the simulation reliability. With the help of a robust geometric model, linear finite elements can be replaced by surface and solid elements which provide a better description of the strain, deformation, tissue inertia and interaction between various tissues, especially in complex anatomic regions such as cervical spine or internal organs. This provides a basis for the study of injury mechanisms, critical load values and the development of new injury criteria. Research development proves the individualised approach to human body modelling to be correct and shows the immense importance of appropriate model verification which is difficult due to specific issues and objective circumstances. A set of collision tests were carried out to verify the human body model. A thorough preparation of biomechanical data and identification of the selected model parameters helped minimize the difference between the measured and simulated impact response.
Project research contributes to the improvement of the finite element method for the simulation of the stress-strain response and occurrence of the material damage. In accordance with experiment results of the monotonous and dynamic tests on soft tissue of the human body, a system is being developed for determining evolutionary equations of the material model and material model parameters by means of a genetic algorithm.
Development results so far have been successfully applied and verified when metal materials are used. Development of the software application for interactive simulation of ride dynamics and vehicle control is a vital part of project activities. It needs to support different aspects of traffic accident analysis, including input data for simulation of the human body dynamics and result analysis. Modular structure of the software application enables interoperability between user interface and the vehicle and biomechanical database, vehicle models and the human body model.
A detailed study of the anatomy and soft tissue properties also proved to be useful in the development of surgical techniques for the treatment of traffic accident and other injur
Significance for the country
The negative effects of traffic accidents have a huge impact on the Slovene society and economy since traffic accidents cause large number of deaths and disabilities among the able-bodied population. Furthermore, long rehabilitation periods, court procedures and high indemnity claims result in high expenses. Project activities are aimed at a better understanding and evaluation of traffic accident injuries which would enable a more objective and faster determination of accident examples in practice.
The project is multidisciplinary and has so far achieved its goals. In project activities, experts from various fields were involved which helped bridge institutional and communication barriers. The project stimulates synergetic effects during the activation of research and other potentials in the Slovene society. The project results so far have been well received among the experts and the need for further research activities has been established. Project participants were asked to give their expertise for traffic accident analyses which demand expert knowledge on biomechanics, vehicle engineering, computer simulations and medicine.
Research in the development of software tools for simulation and presentation of vehicle and human body dynamics has resulted in a flexible and transferable software application which can be applied for various purposes. Since it enables interactive simulation of ride dynamics it is suitable for vehicle behaviour examination which can be carried out during the teaching, the analyses in the phase of vehicle design and analyses of vehicle capability. This, together with the included human body model, enables indirect determination of vehicle occupant loads. Members of the project group were involved in the development of a steel safety barrier the purpose of which is to reduce injuries to traffic accident participants. For the purpose of MFE simulations, detailed geometrical and numerical models of different vehicle types were designed on the basis of a specialised database. Results of the analysis of ride dynamics and vehicle control under various conditions prove that a real-life course of vehicle collision onto a safety barrier significantly differs from Slovene standard provisions which determine the testing of safety barriers. A new design of safety barrier spacers and posts was made for the Slovene territory. Collision simulations show that the new concept enables a more favourable absorption of kinetic energy and reduces injuries to traffic accident participants. In Slovenia, these analyses results can be applied in various fields of engineering and medicine (research and prediction of injury, ergonomics, passive vehicle safety, road infrastructure safety) as well as in the insurance business (analysis of traffic accident costs), traffic safety expert education and the police, justice and road maintenance sector.
Most important scientific results
Annual report
2008,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
final report,
complete report on dLib.si
