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Experimental and computational approach to human brain modelling – aHEAD

Ptak Mariusz, Dymek Mateusz, Sawicki Marek, Fernandes Fábio A. O., Wnuk Maciej, Wilhelm Johannes, Ratajczak Monika, Witkowska Daria, Kwiatkowski Artur, Poźniak Błażej, Kubicki Konrad, Tikhomirov Marta, Druszcz Adam, Chybowski Leszek

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e218, 2023

EN

The human head is a highly complex structure, with a combination of hard and soft tissues and a variety of materials and interactions. Many researchers have used computational approaches to model the head, and several human finite element head models can be found in the literature. However, most of them are not geometrically accurate – for instance, the brain is simplified to a smooth spherical volume, which poses some concerns regarding boundary conditions and geometrical accuracy. Therefore, an advanced head model of a 28-year-old, designated as aHEAD 28 yo (aHEAD: advanced Head models for safety Enhancement And medical Development), has been developed. The model consists entirely of hexahedral elements for 3D structures of the head such as the cerebellum, skull and cerebrum, with detailed geometry of the gyri and sulci. Additionally, it is one of the first human head approaches published in the literature that includes cerebrospinal fluid simulated by Smoothed Particle Hydrodynamics (SPH) and a detailed model of pressurized bridging veins. To support the model’s credibility, this study is focused on physical material testing. A novel comprehensive experimental-computational approach is presented, which involves the brain tissue’s response to induced vibrations. The experiment successfully aimed to validate the material models used in the numerical analysis. Additionally, the authors present a kinematical model validation based on the Hardy experimental cadaver test. The developed model, along with its verification, aims to establish a further benchmark in finite element head modelling and can potentially provide new insights into injury mechanisms.

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Finite element head model for the crew injury assessment in a light armoured vehicle

Burkacki Michał, Wolański Wojciech, Suchoń Sławomir, Joszko Kamil, Gzik-Zroska Bożena, Sybilski Kamil, Gzik Marek

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 2

173--183

EN

Purpose: The aim of this paper was the development of a finite element model of the soldier’s head to assess injuries suffered by soldiers during blast under a light armoured vehicle. Methods: The application of a multibody wheeled armoured vehicle model, including the crew and their equipment, aenabled the researchers to analyse the most dangerous scenarios of the head injury. These scenarios have been selected for a detailed analysis using the finite element head model which allowed for the examination of dynamic effects on individual head structures. In this paper, the authors described stages of the development of the anatomical finite element head model. Results: The results of the simulations made it possible to assess parameters determining the head injury of the soldier during the IED explosion. The developed model allows the determination of the parameters of stress, strain and pressure acting on the structures of the human head. Conclusion: In future studies, the model will be used to carry out simulations which will improve the construction of the headgear in order to minimize the possibility of the head injury.

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Wpływ warunków testu odwzorowującego zderzenie boczne pojazdu w aspekcie zachowania antropomorficznego manekina dziecka

Baranowski P., Damaziak K., Małachowski J., Mazurkiewicz Ł., Muszyński A.

Logistyka

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2015

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nr 4

2364--2371, CD2

PL

W pracy przedstawiono numeryczne symulacje dwóch przypadków uderzenia bocznego i zachowanie ATD w obu tych przypadkach. Jeden przypadek odpowiada procedurze homologacji urządzeń przytrzymujących zdefiniowane według nowo wprowadzonego Regulaminu 129 EKG/ONZ. Drugi przypadek odpowiada uderzeniu od strony przeciwnej do strony mocowania fotelika. Uzyskane wyniki pokazują, że test homologacyjny zdefiniowany w regulacji nie musi odpowiadać najbardziej niekorzystnym warunkom zderzenia. Wskazano też, że ewentualna poprawa wyniku testu dla danego urządzenia przytrzymującego jest relatywnie prosta, podczas gdy poprawa bezpieczeństwa przy uderzeniu od strony przeciwnej wymaga znacznie większych nakładów związanych ze świadomym zaprojektowaniem stref o określonej sztywności.

EN

The paper presents numerical simulations of two cases of side impact and behavior of ATD in both cases. One case corresponds to the procedure of approval of restraining devices defined in the newly introduced UN / ECE Regulation 129. The second case corresponds to the impact from the side opposite the seat mounting. The results show that the side impact test defined in the new Regulation, does not necessarily correspond to the most unfavorable conditions of the collision. It was also indicated that the possible improvement of the restraint device with respect to test results is relatively simple. On the other hand, improving safety when hitting from the opposite side is far more difficult, since it is associated with the design of specific stiffness zones.

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Analiza wpływu zastosowanego elementu energochłonnego mającego bezpośredni kontakt z głową dziecka w aspekcie minimalizacji obciążeń dynamicznych

Baranowski P., Bogusz P., Damaziak K., Małachowski J., Mazurkiewicz Ł., Muszyński A.

Logistyka

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2015

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nr 4

2355--2363, CD2

PL

W pracy przedstawiono numeryczne symulacje trzech przypadków uderzenia bocznego oraz zbadano zachowanie się manekina, a w szczególności obciążeń dynamicznych działających na jego głowę. Przeprowadzone symulacje numeryczne odpowiadają procedurze homologacji urządzeń przytrzymujących zdefiniowane według nowo wprowadzonego Regulaminu 129 EKG/ONZ. Przetestowano trzy rodzaje materiałów dla zagłówka o odmiennych parametrach sztywnościowych. Na drodze analiz komputerowych wykazano, że ewentualna modyfikacja cech materiałowych elementu wchodzącego bezpośrednio w kontakt z głową dziecka, może zminimalizować skutki zderzenia bocznego.

EN

In the paper numerical simulations of three cases of side impact are presented. Dummy behavior was also investigated with the particular attention pointed on the dynamic loads acting on its head. Analyses correspond to the procedure of approval of restraining devices defined in the newly introduced UN / ECE Regulation 129. Three materials with different stiffness properties were adopted for the headrest were tested and compared. Thanks to the computational methods it was shown that the possible modification of material properties of the energy-consuming element directly in contact with the head of child can minimize the effects of side impact.

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Influence of the front part of the vehicle and cyclist’s sitting position on the severity of head injury in side collision

Fanta O., Boucek J., Hadraba D., Jelen K.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 1

105--112

EN

An injury of cyclists during a collision with a car is currently a neglected topic. Most research projects evaluate in detail the injury of pedestrians, but with an increasing number of cyclists it will be necessary to devote more attention to their safety. This study is focused on the most common type of collision and offers insights into the biomechanics of cyclist’s head injury without the use of bicycle helmet. Initial mechanical and kinematic conditions that affect Head Injury Criterion (HIC) after a car hits a cyclist were determined using simulation software MADYMO. In relation to HIC, three different shapes of the front part of the car and three basic cyclist’s positions were compared.

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A Methodology for Assessing Blast Protection in Explosive Ordnance Disposal Bomb Suits

Bass C., Davis M., Rafaels K., Rountree M., Harris R. M., Sanderson E., Andrefsky W., DiMarco G., Zielinski M.

International Journal of Occupational Safety and Ergonomics

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2005

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Vol. 11, No. 4

347--361

EN

To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax. A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn.