A Mathematical Model of Thermal Irradiation Processing of Polymer Coatings during Restoration of Automobile Body Parts

2021 ◽  
Vol 14 (3) ◽  
pp. 376-380
Author(s):  
R. I. Li ◽  
D. N. Psarev ◽  
A. N. Bykonya ◽  
M. R. Kiba
Keyword(s):  
Mathematical Model ◽  
Polymer Coatings ◽  
Body Parts ◽  
Automobile Body ◽  
Thermal Irradiation

scholarly journals Research on an Anthropomorphic Phantom for Evaluation of the Medical Device Electromagnetic Field Exposure SAR

2018 ◽  
Vol 8 (10) ◽  
pp. 1929 ◽  
Author(s):  
Shu Li ◽  
Zengwen Su ◽  
Hao Wang ◽  
Quan Wang ◽  
Haiping Ren
Keyword(s):  
Mathematical Model ◽  
Electromagnetic Radiation ◽  
Medical Device ◽  
Medical Devices ◽  
Debye Model ◽  
World Health ◽  
Endurance Capacity ◽  
Body Parts ◽  
Anthropomorphic Phantom ◽  
Field Exposure

A medical device will emit electromagnetic radiation to its surrounding environment either actively or passively. However, clinicians are unaware as to whether the ambient electromagnetic radiation will exceed the human body’s endurance capacity. In this paper, the mathematical model of electromagnetic parameters devoted to Specific Absorption Rate (SAR) testing of medical devices was established using a Debye Model. Body liquids featuring dielectric properties including the conductivity and permittivity of tissues at various body parts were simulated on the basis of results derived from the model. A simplified anthropomorphic phantom for the SAR test was founded on the basis of geometric parameters by following the principles of resemblance and consistent conductivity. A full-band electromagnetic mathematical model of brain, muscle, heart, lungs, stomach, and kidneys was set up. Electromagnetic radiation levels of a wearable Electrocardiograph monitoring device were measured and found that the maximum electric field intensity was up to 30 V/m, and the electromagnetic radiation SAR value was 0.96 W/kg, which were equivalent to the electromagnetic radiation exposure of the occupational group. The results established that electromagnetic radiation of certain medical devices exceeded the allowed values specified by the World Health Organization (WHO). Therefore, further studies within the field of medicine are required to decide whether additional evaluation measures should be required.

Water diffusion in polymer coatings containing water-trapping particles. Part 2. Experimental verification of the mathematical model

2012 ◽  
Vol 75 (3) ◽  
pp. 207-214 ◽  
Author(s):  
Małgorzata Krzak ◽  
Zbisław Tabor ◽  
Paweł Nowak ◽  
Piotr Warszyński ◽  
Anastasis Karatzas ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Experimental Verification ◽  
Polymer Coatings ◽  
Water Diffusion ◽  
Water Trapping ◽  
The Mathematical Model

scholarly journals Stress-strain state of ship hull structures restored using polymer coating

2021 ◽  
pp. 12-17
Author(s):  
С.И. Корягин ◽  
О.В. Шарков ◽  
Н.Л. Великанов
Keyword(s):  
Mathematical Model ◽  
Polymer Coating ◽  
Strain State ◽  
Metal Layer ◽  
Adhesive Layer ◽  
Metal Structure ◽  
Polymer Coatings ◽  
Calculation Algorithm ◽  
Stress Strain ◽  
Stress Strain State

Применение полимерных покрытий для ремонта корпусных конструкций выдвигает как актуальную задачу определения прочностных характеристик конструкций с покрытиями. Наличие отверстий, сквозной коррозии, являющихся концентраторами напряжений, делает эти места наиболее опасными, с точки зрения потери прочности, герметичности. Чаще всего разрушение происходит по адгезионному слою. Представлена математическая модель, учитывающая сосредоточенные усилия на концах адгезионного слоя композиционной конструкции типа «металл-покрытие». Проведены расчеты нормальных и касательных напряжений. Наибольшие значения напряжений в полимерном покрытии получены на кромке отверстия в слое металла. В результате анализа установлено, что увеличение перекрытия полимерным покрытием контура отверстия и удаленность от контура отверстия приводят к существенному уменьшению величин напряжений. Разработанная математическая модель и алгоритм вычислений позволяют расчетным путем определить напряженно-деформированное состояние металлической конструкции с отверстием и полимерным покрытием. The use of polymer coatings for the repair of hull structures puts forward as an urgent task to determine the strength characteristics of structures with coatings. The presence of holes, through corrosion, which are stress concentrators, makes these places the most dangerous, in terms of loss of strength, tightness. Most often, the destruction occurs along the adhesive layer. A mathematical model is presented that takes into account the concentrated forces at the ends of the adhesive layer of a composite structure of the "metal-coating" type. Calculations of normal and tangential stresses are performed. The highest stress values in the polymer coating are obtained at the edge of the hole in the metal layer. As a result of the analysis, it was found that an increase in the overlap of the polymer coating of the hole contour and the distance from the hole contour lead to a significant decrease in stress values. The developed mathematical model and calculation algorithm allow calculating the stress-strain state of a metal structure with a hole and a polymer coating.

scholarly journals INVESTIGATION OF THE THREE-LINK CRAWLING ROBOTS MOVEMENT ON THE NONDETERMINATED SURFACE

2018 ◽  
Vol 22 (4) ◽  
pp. 6-14
Author(s):  
S. F. Jatsun ◽  
L. Yu. Vorochaeva ◽  
A. V. Malchikov ◽  
А. S. Yatsun
Keyword(s):  
Mathematical Model ◽  
Robot Motion ◽  
Rough Terrain ◽  
Body Parts ◽  
Closed Space ◽  
Straight Line ◽  
Full Scale Tests ◽  
Electronic Compass ◽  
Theoretical Results ◽  
Wheel Track

Bionic principles of locomotion are the most promising for displacement and transporting equipment under the most difficult conditions. Robots gait based on the changing shape of the robots body and interaction with the surface by body parts, can find application when moving over rough terrain, in a closed space of technological and natural cavities, where the use of wheel-track or walking principle is not possible. In this paper, we propose the design of a three-link crawling robot equipped with two-coordinate active joints. The robot is equipped by supporting elements. Some supporting elements has adjustable friction coefficients, which allows realize various types of movement algorithms of the device. The article presents a mathematical model of a three-link crawling robot, which allows to study the process of robot movement, including case when the coefficients of friction of the surface under the supports are not equal to each other. In practice, the surface will most often have an inhomogeneous nondeterministic structure, which will lead to a deviation in straight-line motion. The paper proposes an algorithm and a diagram of an automatic control system that allows robot to move along a given path despite the indeterminate surface. This is achieved by using additional sensors: a digital electronic compass, an accelerometer, a GPS module. The paper presents the results of computational experiments and the results obtained during the full-scale tests of the prototype of a three-link robot motion. At the end of the article, a comparative analysis of the experimental and theoretical results confirming the adequacy of the developed mathematical model and computational algorithms is presented.

Development of Press-Forming Technique for Bent Automobile Body Parts Using In-plane Shear Deformation

2020 ◽  
Vol 61 (710) ◽  
pp. 63-68
Author(s):  
Yusuke FUJII ◽  
Masaki URABE ◽  
Yuji YAMASAKI ◽  
Yoshikiyo TAMAI
Keyword(s):  
Shear Deformation ◽  
Body Parts ◽  
Plane Shear ◽  
Automobile Body ◽  
Press Forming

Research on Multi-Process Route Decision-Making of Warm Forming for Projectile Bodies

2010 ◽  
Vol 97-101 ◽  
pp. 3703-3707
Author(s):  
Shao Jin Yan ◽  
Zhi Min Zhang
Keyword(s):  
Mathematical Model ◽  
Decision Making ◽  
Warm Forming ◽  
Search Process ◽  
Body Parts ◽  
Forming Process ◽  
Process Route ◽  
Feature Based ◽  
Sets Theory ◽  
Polychromatic Sets Theory

A method of using polychromatic sets theory to define the multi-process routes is proposed to solve the problem of process decision-making during the manufacturing process of warm forming for projectile bodies. First, the description of feature-based information model and modeling method of projectile body parts are studied and then a process mathematical model including a contour comprising matrix and a polychromatic graph is established on polychromatic sets theory, last a search process of warm forming process path is given and an application example is also given in the paper.

scholarly journals Approach to increase flexibility in automobile body shops through component-integrated fixture functions

2020 ◽  
Vol 312 ◽  
pp. 03002
Author(s):  
Achim Kampker ◽  
Johannes Triebs ◽  
Jan Ole Hansen
Keyword(s):  
Electric Vehicle ◽  
Combustion Engine ◽  
Product Variety ◽  
Body Part ◽  
Life Cycles ◽  
Body Parts ◽  
Body Shop ◽  
Part Geometry ◽  
Automobile Body ◽  
Product Customization

Due to shorter product life-cycles, increasing product customization and the co-existence of electric and combustion engine vehicles, variant flexibility is gaining importance in the automobile production. The automobile body shop is characterized by inflexible, rigid fixture systems dedicated to meet the geometrical requirements of specific body parts. Changes in part geometry or dimension require the development of new fixture systems, thus increasing product variety results in higher fixture costs. This paper presents an approach for a fixtureless body shop based on component-integrated fixture-functions, increasing variant flexibility and reducing fixture costs. The approach is implemented using a body part assembly of an electric vehicle.

Feature Simplification Techniques for Freeform Surface Models

2003 ◽  
Vol 3 (3) ◽  
pp. 177-186 ◽  
Author(s):  
Nikhil Joshi ◽  
Debasish Dutta
Keyword(s):  
Poor Quality ◽  
Freeform Surface ◽  
Surface Model ◽  
Complete Suppression ◽  
Body Parts ◽  
Automobile Body ◽  
Surface Models ◽  
Basic Features ◽  
Simplification Techniques ◽  
Manual Correction

Freeform surface models are conventionally used to model sheet metal components, such as automobile body parts. Finite element meshes generated automatically for such models have poor quality around small detailed features. Manual correction of the mesh is extremely tedious. An approach presently receiving attention in industry aims to alleviate this problem by automatically simplifying these features in the surface model such that an acceptable mesh is automatically generated. Simplification involves recognition of the feature and modification of its geometry or complete suppression of the feature. Since features such as holes, notches, etc. are punched after the basic shape has been formed, such a simplification will also help in the modelling of forming dies and molds. The ability to detect features will also allow part comparison and classification in surface models. This paper proposes techniques to directly query the CAD data structure to recognize and suppress two basic features, viz. holes and fillets in freeform surface models. It further demonstrates how these techniques can be extended to suppress compound features that are composed of a combination of basic features. Results of a software implementation for the same are discussed with suitable examples and the improvement in mesh quality is demonstrated.

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