3D Model Transformation of Waveguide Slot Array Antenna in Mechanical-Electromagnetic Analyses

2012 ◽  
Vol 562-564 ◽  
pp. 1487-1491
Author(s):  
Mei Chen ◽  
Fei Zheng ◽  
Na Li
Keyword(s):  
Model Transformation ◽  
3D Model ◽  
Geometric Model ◽  
3D Models ◽  
Transformation Method ◽  
Mechanical Analysis ◽  
Array Antenna ◽  
Waveguide Slot ◽  
Electromagnetic Model ◽  
3D Geometric Model

The mechanical errors in a mobile waveguide slot array antenna will finally influence the electromagnetic performances. Hence it is necessary to understand the relationship between them, which requires mechanical-electromagnetic analyses. The 3D models in both mechanical analysis and electromagnetic analysis are greatly different. They need a precise connection and transformation. The paper proposes an effective 3D model transformation method. From 3D geometric model to 3D mechanical model, and then to 3D electromagnetic model, the precise connection and transformation can be finished. It can be used to increase the analysis precision of a complex waveguide slot array antenna.

Improvement of Color Information in the Generation of 3D Models of Real Objects Using Range Intensity Images

2012 ◽  
Vol 523-524 ◽  
pp. 362-367
Author(s):  
Toru Takahama ◽  
Ryo Inomata ◽  
Kenji Terabayashi ◽  
Kazunori Umeda ◽  
Guy Godin
Keyword(s):  
3D Model ◽  
Geometric Model ◽  
Texture Mapping ◽  
3D Models ◽  
Correction Method ◽  
Image Sensor ◽  
Color Images ◽  
Range Image ◽  
Color Information ◽  
Intensity Image

Texture mapping on scanned objects, which is the method to map color images on a 3D geometric model measured by a range image sensor, is often used for constructing a realistic 3D model. Color images are affected by the illumination conditions. Therefore, discontinuities of seams occur when simply applying texture mapping. In this paper, we propose a method for correcting the discontinuities using a range intensity image. A range intensity image is a kind of intensity image that is related to the reflectance ratio of the measured points, simultaneously acquired with a range image using an active range sensor. The method estimates the color information that is not affected by the lighting environment using multiple color images and a range intensity image. As a result, the method is effective to construct a 3D model with seamless color images. The effectiveness of the correction method is illustrated by experiments with real-world objects.

EMBODIMENT OF AUTOMATED DESIGNATION OF SURFACE FINISH OF THE OBJECTS OF THE 3D WORKPIECE MODEL

2020 ◽  
pp. 3-9
Author(s):  
M. S. Chepchurov ◽  
B. S. Chetverikov ◽  
A. N. Maslovskaja ◽  
N. S. Ljubimyj
Keyword(s):  
Surface Finish ◽  
Geometric Modeling ◽  
3D Model ◽  
Geometric Model ◽  
3D Models ◽  
Work Piece ◽  
Electronic Model ◽  
Cad Cam ◽  
Engineering Drawings ◽  
Cross Platform

The article discusses the questions of automation of design engineering in the sphere of the formation of 3D geometric model of work-pieces. The authors have designed and carried out an algorithm in the form of the additional script in the software bundle of the geometric modeling, enabling to execute the designation of surface finish in 3D models. The algorithm is based on the freeware CAD/CAM/CAE system – FreeCAD. The structure of an element from an ordered set of data about a geometric object that identifies the surface roughness is determined that allows to expand the capabilities of methods for providing storage and transmission of data of the electronic model of the product. Creation of additional procedures based on the formed list of surface finish according to the GOST 2.309–73 makes it possible to embody 3D-model transfer to the workplaces. It means that time of embodiment of preproduction and production of work-piece can be cut. Nowadays freeware solid geometry engine with open source code is not used due to the absence of additional specific possibilities of making of engineering drawings according to the regulatory requirements. The authors have offered the method of increasing the capabilities of software bundle of the geometric modeling, which provides the increase of target audience of freeware. The authors propose to use free cross-platform language Python to create the script of designation of surface finish in the space of 3D-model. Usage of the example of the script and its testing can help to design other procedures of making of engineering drawings to create fully-featured free cross-platform geometric designing.

scholarly journals Strength Investigation of an Upholstered Furniture Frame with Side Plates of PB, OSB and PLY by Finite Element Method

2020 ◽  
Vol 71 (3) ◽  
pp. 253-259
Author(s):  
Nelly Staneva ◽  
Yancho Genchev ◽  
Desislava Hristodorova
Keyword(s):  
Finite Element ◽  
3D Model ◽  
Geometric Model ◽  
Failure Criteria ◽  
Rotational Stiffness ◽  
Principal Stresses ◽  
Element Analysis ◽  
Service Load ◽  
Upholstered Furniture ◽  
3D Geometric Model

Comparative analysis of the strength characteristics of one-seat upholstered furniture frame with rails of Pinus Sylvestris L. and side plates of PB, OSB and PLY boards was carried out. 3D geometric model of the upholstered furniture frame was created by Autodesk Inventor Pro®. Linear static analyses were carried out by the method of finite elements (FEM) simulating light-service loading. The orthotropic material characteristics of the used materials were considered in the analyses. Two variants of corner joints in the frame (model A – staples and PVAc; model B - staples, PVAc and strengthening elements under the rail of the seat) were considered. The laboratory established coefficients of rotational stiffness of used staple corner joints in the skeleton were considered in finite element analysis (FEA). As result, the distribution of the maximum and minimum principal stresses in the 3D model of upholstered furniture frame side plates were derived and analysed. The worst failure indexes according to Tsai-Wu failure criteria were calculated at heavy-service load. The study provided database of strength values that can help in the engineering of upholstered furniture frames with side plates of PB, OSB and PLY.

3d Geometric Model of Transparent Tower Equipment Display in OpenGL

2014 ◽  
Vol 722 ◽  
pp. 281-284 ◽  
Author(s):  
Hai Ru Yang ◽  
Guo Zhi Chen ◽  
Hui Zhen Wang ◽  
Liang Li
Keyword(s):  
Dynamic Model ◽  
3D Model ◽  
Geometric Model ◽  
Three Dimensional ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Tower Equipment ◽  
3D Geometry ◽  
High Level ◽  
3D Geometric Model

It’s difficult to describe the 3d geometry and to establish the 3d model of tower equipment in OpenGL. High-level command functions to define complex three-dimensional modeling is not provided in OpenGL. This paper introduces 3d model of the tower equipment how to display dynamically in OpenGL. Interface of OpenGL import 3d model is description in detailed. Storaging format and reading file of STL (Stereo Lithography) are elaborated. How to build the 3d model is descripted. When tower equipment displayed dynamically, what is the key step to establish the model of tower equipment. The dynamic model of the whole tower equipment is displayed, in order to see clearly the structure of tower equipment.

LTCC Partially-Filled Post-Wall Rectangular-Waveguide Slot Array Antenna in the Millimeter-Wave Band

2012 ◽  
Vol E95.C (10) ◽  
pp. 1635-1642 ◽  
Author(s):  
Yuanfeng SHE ◽  
Jiro HIROKAWA ◽  
Makoto ANDO ◽  
Daisuke HANATANI ◽  
Masahiro FUJIMOTO
Keyword(s):  
Millimeter Wave ◽  
Rectangular Waveguide ◽  
Array Antenna ◽  
Wave Band ◽  
Waveguide Slot ◽  
Millimeter Wave Band

Hoist Sheave Structure Optimization and Lightweight

2015 ◽  
Vol 741 ◽  
pp. 133-137
Author(s):  
Xian Zhao Jia ◽  
Yong Fei Wang
Keyword(s):  
Working Condition ◽  
Geometric Model ◽  
Structure Optimization ◽  
Element Model ◽  
Stiffened Plate ◽  
Optimal Result ◽  
Ansys Software ◽  
Table Analysis ◽  
3D Geometric Model ◽  
Relational Table

To ensure wheel body of the hoisting sheave strength and stability condition. For the purpose of wheel body lightweighting. There are two schemes to reduce body weight.Reduce the spokes at the same time increase the ring stiffened plate, and reduce the spokes at the same time change the spokes width and thickness.The wheel body was established based on Pro/E 3D geometric model. Import the mesh in the Workbench of ANSYS software for finite element model. Statics analysis to select the optimized scheme. Establish a hoisting sheave wheel body under the actual working condition of widening the width - deformation - wheel weight relational table. Analysis to lightweight at the same time ensure that stiffness of wheel,then it can obtaine the optimal result.

scholarly journals Complex wall modeling for hemodynamic simulations of intracranial aneurysms based on histologic images

2021 ◽  
Vol 16 (4) ◽  
pp. 597-607
Author(s):  
Annika Niemann ◽  
Samuel Voß ◽  
Riikka Tulamo ◽  
Simon Weigand ◽  
Bernhard Preim ◽  
...  
Keyword(s):  
Wall Thickness ◽  
Vessel Wall ◽  
Intracranial Aneurysms ◽  
Geometric Model ◽  
Image Data ◽  
Outer Wall ◽  
3D Models ◽  
Patient Specific ◽  
Intracranial Vessel ◽  
Hemodynamic Simulations

Abstract Purpose For the evaluation and rupture risk assessment of intracranial aneurysms, clinical, morphological and hemodynamic parameters are analyzed. The reliability of intracranial hemodynamic simulations strongly depends on the underlying models. Due to the missing information about the intracranial vessel wall, the patient-specific wall thickness is often neglected as well as the specific physiological and pathological properties of the vessel wall. Methods In this work, we present a model for structural simulations with patient-specific wall thickness including different tissue types based on postmortem histologic image data. Images of histologic 2D slices from intracranial aneurysms were manually segmented in nine tissue classes. After virtual inflation, they were combined into 3D models. This approach yields multiple 3D models of the inner and outer wall and different tissue parts as a prerequisite for subsequent simulations. Result We presented a pipeline to generate 3D models of aneurysms with respect to the different tissue textures occurring in the wall. First experiments show that including the variance of the tissue in the structural simulation affect the simulation result. Especially at the interfaces between neighboring tissue classes, the larger influence of stiffer components on the stability equilibrium became obvious. Conclusion The presented approach enables the creation of a geometric model with differentiated wall tissue. This information can be used for different applications, like hemodynamic simulations, to increase the modeling accuracy.

scholarly journals Fast 3D Rotation Estimation of Fruits Using Spheroid Models

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2232
Author(s):  
Antonio Albiol ◽  
Alberto Albiol ◽  
Carlos Sánchez de Merás
Keyword(s):  
Fruit Quality ◽  
3D Model ◽  
Geometric Model ◽  
Fruit Shape ◽  
Single Camera ◽  
Global Score ◽  
Topographic Map ◽  
Single Image ◽  
Large Effort ◽  
Fruit Surface

Automated fruit inspection using cameras involves the analysis of a collection of views of the same fruit obtained by rotating a fruit while it is transported. Conventionally, each view is analyzed independently. However, in order to get a global score of the fruit quality, it is necessary to match the defects between adjacent views to prevent counting them more than once and assert that the whole surface has been examined. To accomplish this goal, this paper estimates the 3D rotation undergone by the fruit using a single camera. A 3D model of the fruit geometry is needed to estimate the rotation. This paper proposes to model the fruit shape as a 3D spheroid. The spheroid size and pose in each view is estimated from the silhouettes of all views. Once the geometric model has been fitted, a single 3D rotation for each view transition is estimated. Once all rotations have been estimated, it is possible to use them to propagate defects to neighbor views or to even build a topographic map of the whole fruit surface, thus opening the possibility to analyze a single image (the map) instead of a collection of individual views. A large effort was made to make this method as fast as possible. Execution times are under 0.5 ms to estimate each 3D rotation on a standard I7 CPU using a single core.

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