Mathematical Model and microCT-Based Kinematic Analysis of the Rostrum Mouthparts in Cyrtotrachelus buqueti Guer (Coleoptera: Curculionidae)

2021 ◽  
pp. 1-18
Author(s):  
Longhai Li ◽  
Ce Guo ◽  
Shun Xu ◽  
Huafeng Guo ◽  
Ping Yu ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Edge Detection ◽  
Kinematic Analysis ◽  
Least Squares Method ◽  
Scanning Electron Micrographs ◽  
Micro Computed Tomography ◽  
Element Analysis ◽  
Nonlocal Means ◽  
Bamboo Shoots ◽  
Cyrtotrachelus Buqueti

Abstract 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.

Nanoindentation Properties and Finite Element Analysis of the Rostrum of Cyrtotrachelus buqueti Guer (Coleoptera: Curculionidae)

2019 ◽  
Vol 25 (3) ◽  
pp. 786-797
Author(s):  
Longhai Li ◽  
Ce Guo ◽  
Shun Xu ◽  
Yaopeng Ma ◽  
Zhiwei Yu
Keyword(s):  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Structural Information ◽  
Three Dimensional ◽  
Micro Computed Tomography ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Hybrid Transmission ◽  
Cyrtotrachelus Buqueti

AbstractThis work focuses on the application of nanoindentation measurements and the finite element method for analyzing the mechanical properties of the rostrum of the outstanding driller Cyrtotrachelus buqueti Guer. Nanoindentation tests were carried out to measure the Young's modulus and hardness of the rostrum, with the results for the “dry” samples being 13.886 ± 0.75 and 0.368 ± 0.0445 GPa, respectively. The values for the “fresh” samples showed no clear difference from those of the “dry” ones. Moreover, field observation was conducted to determine the motion behaviors of the rostrum on the weevil. Micro-computed tomography technology was employed to obtain structural information about the rostrum, using 9 µm slices. A real three-dimensional model of the rostrum was created using the MIMICS application. Finally, the mechanical properties of the rostrum were determined by finite element analysis. It was concluded that the rostrum provides an ideal biological template for the design of biocomposite materials and lightweight tube-shaped structures. The properties determined in this study can potentially be applied in different fields, such as in the design of automotive hybrid transmission shafts, helicopter tail drive shafts, robotic arms, and other sandwich structures in aerospace engineering.

Research on Generator Excitation Parameter Identification - PSS Low-Pass Link Parameter Identification

2013 ◽  
Vol 805-806 ◽  
pp. 716-720
Author(s):  
Tao Xu ◽  
Tian Long Shao ◽  
Dong Fang Zhang
Keyword(s):  
Mathematical Model ◽  
Parameter Identification ◽  
Least Squares Method ◽  
Least Square Method ◽  
Least Square ◽  
National Standards ◽  
Matlab Software ◽  
Low Pass ◽  
Newton Iterations ◽  
The Mathematical Model

Combined with the contents of the study-PSS low-pass link parameter identification. Least-squares method is selected. Using least-square method for PSS low-pass link mathematical model are also deduced. For the results, because of the mathematical model is solving nonlinear equations, cannot used by the Newton method directly. So we choose to use Newton iterations, with this feature, choose to use MATLAB software to solve the equation. Identification of the use of MATLAB software lags after the PSS parameters obtained recognition results compared with national standards, identifying and verifying the practicability.

scholarly journals Real-time finite element analysis allows homogenization of tissue scale strains and reduces variance in a mouse defect healing model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Graeme R. Paul ◽  
Esther Wehrle ◽  
Duncan C. Tourolle ◽  
Gisela A. Kuhn ◽  
Ralph Müller
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Fracture Healing ◽  
Real Time ◽  
Mechanical Stimulus ◽  
Stimulus Level ◽  
Micro Computed Tomography ◽  
Reference Distribution ◽  
Element Analysis ◽  
Computed Tomography Images

AbstractMechanical loading allows both investigation into the mechano-regulation of fracture healing as well as interventions to improve fracture-healing outcomes such as delayed healing or non-unions. However, loading is seldom individualised or even targeted to an effective mechanical stimulus level within the bone tissue. In this study, we use micro-finite element analysis to demonstrate the result of using a constant loading assumption for all mouse femurs in a given group. We then contrast this with the application of an adaptive loading approach, denoted real time Finite Element adaptation, in which micro-computed tomography images provide the basis for micro-FE based simulations and the resulting strains are manipulated and targeted to a reference distribution. Using this approach, we demonstrate that individualised femoral loading leads to a better-specified strain distribution and lower variance in tissue mechanical stimulus across all mice, both longitudinally and cross-sectionally, while making sure that no overloading is occurring leading to refracture of the femur bones.

Research on Deflection Analysis and Compensation Method of Ram of Boring and Milling Machining Center

2014 ◽  
Vol 633-634 ◽  
pp. 693-698
Author(s):  
Long Xin ◽  
Shi Chao Cui ◽  
Qi Lin Shu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Least Squares Method ◽  
Preliminary Calculation ◽  
Element Analysis ◽  
Object A ◽  
Machining Center ◽  
Deflection Analysis ◽  
Long Stroke ◽  
The Relationship

In this paper, the ram of boring and milling machining center is taken as the research object. A new method that hydraulic pull rods compensation is proposed to solve the problem of deformation compensation of long stroke ram of boring and milling machining center. Firstly, the method of finite element analysis is used to get the laws of ram deformation and the relationship curve between the ram deformation and the stroke of ram. Secondly, the preliminary calculation value of pull rods compensation force is derived based on the theoretical analysis of material mechanics. The relationship curve between compensation force and the stroke of ram is obtained by finite element analysis and polynomial least squares method. Finally, the analyzed results are as follows: the laws of ram deformation distribution is accurately predicted by the used method, the deflection error of the ram is well controlled,and the machining precision is significantly improved.

scholarly journals The identification of a device based on a Peltier element by the least squares method

2020 ◽  
pp. 17-27
Author(s):  
Vladimir Grinkevich ◽  
Keyword(s):  
Mathematical Model ◽  
Least Squares ◽  
Least Squares Method ◽  
Control Object ◽  
Object Identification ◽  
Model Parameters ◽  
Peltier Element ◽  
Transport Delay ◽  
Non Linear ◽  
The Mathematical Model

The evaluation of the mathematical model parameters of a non-linear object with a transport delay is considered in this paper. A temperature controlled stage based on a Peltier element is an identification object in the paper. Several input signal implementations are applied to the input of the identification object. The least squares method is applied for the calculation of the non-linear differential equitation parameters which describe the identification object. The least squares method is used due to its simplicity and the possibility of identification non-linear objects. The parameters values obtained in the process of identification are provided. The plots of temperature changes in the temperature control system with a controller designed based on the mathematical model of the control object obtained as a result of identification are shown. It is found that the mathematical model obtained in the process of identification may be applied to design controllers for non-linear systems, in particular for a temperature stage based on a Peltier element, and for self-tuning controllers. However, the least square method proposed in the paper cannot estimate the transport delay time. Therefore it is required to evaluate the time delay by temperature transient processes. Dynamic object identification is applied when it is required to obtain a mathematical model structure and evaluate the parameters by an input and output control object signal. Also, identification is applied for auto tuning of controllers. A mathematical model of a control object is required to design the controller which is used to provide the required accuracy and stability of control systems. Peltier elements are applied to design low-power and small- size temperature stage . Hot benches based on a Peltier element can provide the desired temperature above and below ambient temperature.

Predicting the Large Deflection Path of End-Loaded Tapered Cantilever Beams

2000 ◽  
Author(s):  
Matthew B. Parkinson ◽  
Gregory M. Roach ◽  
Larry L. Howell
Keyword(s):  
Mathematical Model ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Euler Equation ◽  
Large Deflection ◽  
Nonlinear Finite Element ◽  
Cantilever Beams ◽  
Element Analysis ◽  
Moments Of Inertia ◽  
Physical Testing

Abstract A simple (quadratic) mathematical model for predicting the deflection path of both non-tapered and continuously tapered cantilever beams loaded with a vertical end force is presented. It is based on the proposition that the path is a function of the ratio of the endpoints’ moments of inertia. The model is valid for both small and large (the tip makes a 70 degree angle with the horizontal) deflections. This was verified through physical testing, comparison to solution of the Bernoulli-Euler equation, and results obtained through nonlinear finite element analysis. Predicted endpoint deflections were found to be accurate within 1.8% of the actual deflection path for moment of inertia ratios varying from 1:1 to 1000:1.

scholarly journals Analysis of microscopic bone properties in an osteoporotic sheep model: a combined biomechanics, FE and ToF-SIMS study

2019 ◽  
Vol 16 (151) ◽  
pp. 20180793 ◽  
Author(s):  
R. Müller ◽  
A. Henss ◽  
M. Kampschulte ◽  
M. Rohnke ◽  
A. C. Langheinrich ◽  
...  
Keyword(s):  
Biomechanical Testing ◽  
Tissue Level ◽  
Osteoporotic Bone ◽  
Compression Tests ◽  
Micro Computed Tomography ◽  
Deficient Diet ◽  
Element Analysis ◽  
Sheep Model ◽  
Tissue Properties ◽  
Bone Properties

The present study deals with the characterization of bone quality in a sheep model of postmenopausal osteoporosis. Sheep were sham operated ( n = 7), ovariectomized ( n = 6), ovariectomized and treated with deficient diet ( n = 8) or ovariectomized, treated with deficient diet and glucocorticoid injections ( n = 7). The focus of the study is on the microscopic properties at tissue level. Microscopic mechanical properties of osteoporotic bone were evaluated by a combination of biomechanical testing and mathematical modelling. Sample stiffness and strength were determined by compression tests and finite-element analysis of stress states was conducted. From this, an averaged microscopic Young’s modulus at tissue level was determined. Trabecular structure as well as mineral and collagen distribution in samples of sheep vertebrae were analysed by micro-computed tomography and time-of-flight secondary ion mass spectrometry. In the osteoporotic sheep model, a disturbed fibril structure in the triple treated group was observed, but bone loss only occurred in form of reduced trabecular number and thickness and cortical decline, while quality of the residual bone was preserved. The preserved bone tissue properties in the osteoporotic sheep model allowed for an estimation of bone strength which behaves similar to the human case.

THE FLOW FIELD ACTING ON THE FLUTTERING PROFILE, KINEMATICS, FORCES AND TOTAL MOMENT

2013 ◽  
Vol 13 (07) ◽  
pp. 1340009 ◽  
Author(s):  
JAN KOZÁNEK ◽  
VÁCLAV VLČEK ◽  
IGOR ZOLOTAREV
Keyword(s):  
Mathematical Model ◽  
Least Squares ◽  
High Speed ◽  
Least Squares Method ◽  
High Speed Camera ◽  
Aerodynamic Forces ◽  
Total Moment ◽  
Airfoil Surface ◽  
Measured System ◽  
Simplified Mathematical Model

A high speed camera was used for interferometry visualization (in different phases of the motion) of the fluttering NACA0015 profile supported in a translational and rotational manner. First, the simplified mathematical model of the support of investigated profile was identified from minimum least squares differences between modeled and measured system responses. A special graphical Matlab procedure was proposed for evaluation of interferograms. Kinematic analysis defining motion of the profile as a function of time was obtained by a regression using the least squares method. Numerical integration of pressure functions around the airfoil surface allows for calculation of the resulting aerodynamic forces and moments.

scholarly journals Spatial Correlations of Trabecular Bone Microdamage with Local Stresses and Strains Using Rigid Image Registration

2011 ◽  
Vol 133 (6) ◽  
Author(s):  
Srinidhi Nagaraja ◽  
Oskar Skrinjar ◽  
Robert E. Guldberg
Keyword(s):  
Finite Element ◽  
Image Registration ◽  
Trabecular Bone ◽  
Tissue Level ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Element Analysis ◽  
Registration Algorithm ◽  
Local Bone ◽  
Local Stresses

Although microdamage is known to accumulate in trabecular bone with overloading and aging, the tissue-level stresses and strains associated with local bone failure are not well known. Local correlation of microdamage with microstructural stresses and strains requires methods to accurately register histological sections with micro-computed tomography (micro-CT) based finite element models. In addition, the resolution of correlation (i.e., grid size) selected for analysis may affect the observed results. Therefore, an automated, repeatable, and accurate image registration algorithm was developed to determine the range of local stresses and strains associated with microdamage initiation. Using a two-dimensional rigid registration algorithm, bone structures from histology and micro-CT imaging were aligned. Once aligned, microdamaged regions were spatially correlated with local stresses and strains obtained from micro-CT based finite element analysis. Using this more sophisticated registration technique, we were able to analyze the effects of varying spatial grid resolution on local stresses and strains initiating microdamage. The results indicated that grid refinement to the individual pixel level (pixel-by-pixel method) more precisely defined the range of microdamage initiation compared to manually selected individual damaged and undamaged trabeculae. Using the pixel-by-pixel method, we confirmed that trabecular bone from younger cows sustained higher local strains prior to microdamage initiation compared to older bone.

scholarly journals MODELLING A COMPLIANT-BASED PRECISE POSITIONING STAGE / AUKŠTO TIKSLUMO POZICIONAVIMO SISTEMOS MODELIAVIMAS TAIKANT BESIDEFORMUOJANČIUS MECHANIZMUS

2013 ◽  
Vol 6 (4) ◽  
pp. 523-527 ◽  
Author(s):  
Giedrius Augustinavičius ◽  
Audrius Čereška
Keyword(s):  
Mathematical Model ◽  
Finite Element Analysis ◽  
Positioning System ◽  
Element Analysis ◽  
Precise Positioning ◽  
Positioning Systems ◽  
Positioning Stage ◽  
Amplification Mechanism ◽  
Analytical Approaches ◽  
The Mathematical Model

The paper presents modelling precise dual axis flexure-based precision positioning systems for micro-positioning applications. The positioning system is featured with monolithic architecture, flexure-based joints and piezo stacks. Its workspace has been evaluated via analytical approaches. Amplification mechanism is optimally designed. The mathematical model of the positioning system has been derived and verified by resorting to finite element analysis (FEA). The established analytical and (FEA) models are helpful for optimizing reliable architecture and improving the performance of the positioning system. Santrauka Straipsnyje pristatomas dviejų ašių didelio tikslumo pozicionavimo sistemos su paketiniais pjezovykdikliais modeliavimas, taikant besideformuojančius vientiso kūno mechanizmus. Pozicionavimo sistemą sudaro besideformuojančio vientiso kūno mechanizmas ir paketiniai pjezovykdikliai. Besideformuojantis vientiso kūno mechanizmas norimam poslinkiui pasiekti buvo optimizuotas Solidworks Simulation programiniu paketu. Platformų poslinkiams apskaičiuoti sudarytas matematinis modelis, kurio patikimumas patikrintas baigtinių elementų metodu. Sudaryto matematinio modelio ir rezultatų, gautų baigtinių elementų metodu, skirtumai yra mažesni nei 5 %, todėl pasiūlyta modeliavimo metodika gali būti taikoma kuriant pozicionavimo sistemas su besideformuojančiais elementais.

Sign in / Sign up

Export Citation Format

Share Document