To uncover the chewing mechanism of Cyrtotrachelus buqueti Guer, a mathematical model was created and a kinematic analysis of its rostrum mouthparts was conducted for, to our knowledge, the first time. To reduce noise and improve the quality of scanning electron micrographs of the weevil's mouthparts, nonlocal means and integral nonlocal means algorithms were proposed. Additionally, based on a comparison and analysis of five classical edge detection algorithms, a multiscale edge detection algorithm based on the B-spline wavelet was used to obtain the boundaries of structural features. The least squares method was used to analyze the data of the mouthparts to fit the mathematical model and fitted curves were obtained using Gaussian equations. The results show that curvature and concave–convex variations of the weevil's mouthparts can highlight fluctuations in friction effects when it chews bamboo shoots, which is helpful in preventing debris from bamboo shoots or other debris from sticking to the mouthpart surfaces. Moreover, this paper highlights the utility of micro-computed tomography (microCT) for three-dimensional (3D) reconstruction and a flowchart is suggested. The reconstructed slices were 9.0 μm thick and an accurate 3D rendered model was obtained from a series of microCT slices. Finally, a real model of the rostrum mouthparts was analyzed using finite-element analysis. The results provide a biological template for the design of a novel bionic drilling mechanism.

In this study, a novel inflatable belt-type clamp is introduced and its performance is verified. Finite element simulations are performed to compare the performance of three different aorta clamping systems. In every case, the aorta is modeled as a simple hollow cylinder made of linearly elastic material. For a traditional surgical clamp in which the jaws remain inclined to one another as they close around the aorta, the maximum normal stress within the aorta wall is found to be 806kPa. It is shown that the numerical results are in good qualitative agreement with the experimental results obtained using a pressure sensitive film. The simulation results for a modified clamp in which the jaws remain parallel during the clamping operation show that the maximum normal stress is reduced to 222kPa. However, two regions of maximum stress are induced within the aorta wall. Finally, the numerical results for a novel inflatable belt-type clamp show that the maximum normal stress is equal to approximately 221kPa. In contrast to the modified clamp, the stress is uniformly distributed around the perimeter of the aorta, and thus the risk of aortic dissection is significantly reduced.

Le présent article traite des interactions fluide/structure dans le domaine des moyennes fréquences. En effet, dans ce domaine fréquentiel, il n'est pas possible de modéliser un système fluide/structure en FEM car la densité modale du milieu fluide est trop importante, ni de le modéliser en SEA car cette modélisation ne serait pas valide. Une méthode hybride FEM/SEA est donc développée : la méthode SEA-like. La méthode SEA-like est une méthode énergétique dont la matrice est calculée avec des méthodes de type "basses fréquences". Les coefficients SEA-like sont calculés avec une condensation dynamique afin de prendre en compte la densité modale importante dans le système. Dans cet article, la matrice SEA-like d'un système couplé plaque/cavité est calculé avec une analyse modale. On obtient alors une expression simplifiée des coefficients SEA-like. La matrice SEA-like est alors validée dans le domaine des basses fréquences avec modélisation FEM du système couplé et dans le domaine des hautes fréquences avec une modélisation SEA du système couplé.