The aorta is the largest artery of the human body, and it is considered in the continuous medium mechanics as a hyperelastic material for its biological properties. The thoracic aorta is directly affected in vehicular collision events by compression generated between the ribcage and the three-point seatbelt tension producing injuries in the artery wall. A three-dimensional model of the thoracic aorta was constructed from digital tomographic images considering the ascending aorta, the aortic arch, and the descending aorta. The model obtained presents acceptable characteristics such as a length of 222.8 mm and an ascending aortic diameter of 22.7 mm, 22.7 mm in the aortic arch, and 16.09 mm in the descending aorta. A 150 ms time numerical simulation was developed through the finite element method (MEF), and the model was analyzed simulating a compression load on the artery at its front location. Boundary conditions were considered by selecting specific nodes in the model, such as the points where the artery is held in the thorax with other elements. In addition, displacement nodes were considered to establish a natural behavior of the artery. The outcomes show significant displacements in the artery wall. The most affected areas are the aortic arch and descending aorta, whose displacements reach 14 mm from their original position. Based on the abbreviated injury scale (AIS), the degree of injury to the aorta in this collision event is estimated, an AIS 2 with a moderate severity index and required medical attention.

This research shows an image processing method to determine the liver tissue’s mechanical behavior under physiological damage caused by fibrosis pathology. The proposed method consists of using a liver tissue CAD/CAE model obtained from a tomography of the human abdomen, where the diaphragmatic surface of this tissue is compressed by a moving flat surface. For this work, two tools were created—the first to analyze the deformations and the second to analyze the displacements of the liver tissue. Gibbon and MATLAB^® were used for numerical analysis with the FEBio computer program. Although deformation in the scenario can be treated as an orthogonal coordinate system, the relationship between the total change in height (measured) and the deformation was obtained. The outcomes show liver tissue behavior as a hyperelastic model; the Mooney–Rivlin mathematical characterization model was proposed in this case. Another method to determine the level of physiological damage caused by fibrosis is fractal analysis. This work used the Hausdorff fractal dimension (HFD) method to calculate and analyze the 2D topological surface.

This study examined injuries sustained by a six-year-old child dummy in a numerical dolly rollover crash using a Toyota Yaris 2010. A harmonic dynamic system (HDS) composed of spring, dampers, and masses with a Low Back Booster (LBB) is denominated as HDS-LBB model. The HDS-LBB was designed to allow damping movements along three Cartesian axes (X, Y, Z) to reduce the energy transferred to the child by a motor vehicle accident and avoid a high injury risk. The HDS-LBB incorporates springs into the vertical axis to decrease the vertical movement during the rollover. The numerical analysis was conducted using LS-Dyna® R12.1 version during an interval of 1 s, and the boundary conditions were set by the Federal Motor Vehicle Safety Standard (FMVSS) 213 for child restraint recommendations and the FMVSS 208 for a dolly rollover procedure. Data on head and thorax decelerations, neck flexion-extension, and thoracic deflection were acquired at a rate of 1 ms. The injury values obtained by the HDS-LBB were compared with the injury values by another configuration denominated LBB-ISOFIX to assess the effectiveness of the model proposed. The results show a higher peak injury value in the neck and thorax because of seatbelt displacement across the child’s shoulder. Nevertheless, despite this seatbelt behavior, the injuries sustained remained below the Injury Assessment Reference Values (IARVS).

En este trabajo se llevó a cabo el uso de herramientas computacionales para predicción de falla en el material PLA (Ácido Poli Láctico) obtenido mediante impresión 3D. Las evaluaciones en piezas en etapa de prototipo suelen tener cambios hasta conseguir un diseño a detalle, estos cambios provienen de ensayos que se realizan para comprobar su funcionamiento. La implementación de simulaciones numéricas y paqueterías de predicción ha revolucionado la forma en que se modifican piezas hasta alcanzar una manufactura óptima para aplicación en diferentes sectores. La técnica de moteado en piezas y empleado el método de correlación de imagen digital (DIC), se ha establecido como solución para inspección en piezas que son sometidas a ensayos de esfuerzos obteniendo buenos resultados. Los desplazamientos analizados en la muestra son verificados en relación al esfuerzo de compresión aplicado obteniendo un máximo de desplazamiento hallado por medio de los patrones en la muestra de hasta 15.0% aplicando una fuerza de 1 N en 15.725 s, se validaron los resultados empleando una paquetería para simulación y análisis de esfuerzos.

According to the World Health Organization (WHO), approximately 1.3 billion people experience visual impairments. Daily exposure to various levels of luminous beams directly impacts the front layer of the visible structure, leading to corneal injuries. To comprehensively understand this, we reconstructed a three-dimensional model utilizing the PENTACAM^® system. This enabled us to accurately determine the 50th percentile dimensions of the fibrous layer of the eyeball. Using the Ogden mathematical model, we developed a 3D cornea model, treating it as a soft tissue with predictable behavior, considering mechanical properties such as viscoelasticity, anisotropy, and nonlinearity. Employing the Finite Element Method (FEM), we analyzed five distinct test scenarios to explore the structural response of the cornea. Luminous beam properties were instrumental in establishing varying mechanical loads, leading to structural deformations on the corneal surface. Our findings reveal that when a smartphone’s screen emits light at a frequency of 651.72 THz from 200 mm, displacements in the corneal layer can reach up to 9.07 µm. The total load, computed by the number of photons, amounts to 7172.637 Pa.

Currently, silicone is a common material used in medical research and biomedical applications. This research aims to characterize extra-soft platinum silicone (shore A 00 50) and compare its mechanical behavior with that of the human thoracic aorta. By developing molds to get samples, for tensile testing according to ISO 37 and ASTM D412, and for compression testing according to ISO 7743 and ASTM D575, using a universal testing machine for tensile and compression tests, and applying digital image correlation (DIC) algorithms, the mechanical properties were characterized in a total of 10 tensile samples and 6 compression samples. The results show an ultimate tensile strength up to 1.77 ± 0.12 MPa in the ASTM samples and 2.10 ± 0.14 MPa in the ISO samples; alongside an incremental elastic module of 80.08 ± 7.94 kPa and 117.98 ± 11.39 kPa; finally, an elongation at break of 1114.49 ± 76.77% and 936.08 ± 63.56%, corresponding to the values of a healthy thoracic aorta. The replica of the thoracic aorta in this material was developed by a brush method, with a thickness of 1.82 mm, a length from the aortic arch to the descending aorta of 200.49 mm, and diameters of 20.45 and 16.05 mm for the ascending and descending aorta, respectively.