Surface Contact Analysis for a Spatial Cam Mechanism

1997 ◽  
Vol 119 (2) ◽  
pp. 169-177 ◽  
Author(s):  
W. H. Wang ◽  
C. H. Tseng ◽  
C. B. Tsay
Keyword(s):  
Geometrical Model ◽  
Displacement Function ◽  
Contact Analysis ◽  
Contact Condition ◽  
Contact Phenomenon ◽  
New Model ◽  
Edge Contact ◽  
Cam Mechanism ◽  
Surface Contact ◽  
Cylindrical Roller

This paper proposes and analyzes a new meshing condition between a modified hyperboloidal roller follower and a spatial cam surface. This new geometrical model can be utilized to avoid the edge contact phenomenon between a cylindrical roller follower and its mating cam surface. In the new model a modified hyperboloidal roller follower is selected to replace the original cylindrical roller follower. Once the new spatial cam mechanism is modeled by means of surface contact analysis (SCA), the contact condition between the modified hyperboloidal roller follower and the cam surface is clearly derived. Errors in the displacement function and the contact path arising from assembly errors are also analyzed. This study assists the manufacture and assembly of more accurate and higher quality spatial cam mechanisms.

Study on Reconstruction of Fractal Rough Surfaces

2013 ◽  
Vol 278-280 ◽  
pp. 527-530
Author(s):  
Nan Zhang ◽  
Li Hua Wang ◽  
Yu Song He ◽  
Zi Lu
Keyword(s):  
Rough Surfaces ◽  
Three Dimensional ◽  
Computer Models ◽  
Contact Analysis ◽  
Solid Model ◽  
Fractal Surfaces ◽  
Contact Conductivity ◽  
Surface Contact

The geometric topography of the engineering surfaces play key roles in many issue of engineering and science including the analysis of friction, wear, lubrication, sealing and contact conductivity, especially microcosmic surface contact, thus the characterization of surface is one of the most important topics of tribology. Using the technology of CAD/CAE, a three-dimensional solid model of the fractal surfaces was established and meshed to provide the computer models for microcosmic contact analysis between two rough surfaces in this paper.

scholarly journals Determinación Mejorada del Volumen de Pesas Patrón por Medición Geométrica

2019 ◽  
Vol 7 (20) ◽  
Author(s):  
Omar Jair Purata Sifuentes
Keyword(s):  
Mathematical Model ◽  
Current Model ◽  
Title Page ◽  
Manufacturing Processes ◽  
Volume Determination ◽  
New Model ◽  
Proposed Model ◽  
Surface Contact ◽  
Geometric Measurement

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span><strong>Purpose</strong>  </span><span>̶  </span><span>to develop an improved mathematical model for volume determination of standardized weights by geometric measurement.</span></p><p><span><strong>Methodology</strong>  </span><span>̶  </span><span>the new model eliminates an assumption considered in the current model published in the OIML R 111-1 recommendation, since it considers existing deviations from the assumed shape of the weights in the current model, specifically in the so-called knob and ring sections. These deviations might originate during the manufacturing processes of the weights. </span></p><p><span><strong>Results</strong>  </span><span>̶  </span><span>an improved mathematical model for the calculation of the volume of standard weights by geometric measurement was deduced. Additionally, the model has the advantage of eliminating the risk of scratching the weights, which makes it possible to extend the use of the new model to higher accuracy classes.</span></p><p><span><strong>Limitations</strong>  </span><span>̶  </span><span>the proposed model involves the possibility of making geometric measurements without surface contact of the weights, for example, with an optical comparator. </span></p><p><span><strong>Findings</strong>  </span><span>̶  </span><span>an assessment of the current model against data previously published allows highlighting the relevance and higher accuracy of the new model, which makes it possible to calculate the density of standard weights, even for E class, through only geometric measurements. </span></p></div></div></div>

A Reconstruction and Contact Analysis Method of Three-Dimensional Rough Surface Based on Ellipsoidal Asperity

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Yuqin Wen ◽  
Jinyuan Tang ◽  
Wei Zhou ◽  
Lin Li
Keyword(s):  
Rough Surface ◽  
Rough Surfaces ◽  
Minimum Mean Square Error ◽  
Three Dimensional ◽  
Contact Fatigue ◽  
Contact Analysis ◽  
Analysis Method ◽  
Surface Asperity ◽  
Surface Contact ◽  
Rough Surface Contact

Abstract The 3D rough surface modeling and contact analysis is a difficult problem in the study of rough surface contact. In this paper, a new method for reconstruction and contact analysis of asperities on 3D rough surfaces is proposed based on real rough surfaces. Watershed algorithm is used to segment and determine the area of asperities on the rough surface. According to the principle of minimum mean square error, ellipsoid fitting is carried out on asperities. Based on the elastic-plastic contact model of a single ellipsoidal asperity, a stable and efficient method for 3D rough surface contact analysis and calculation is proposed. Compared with existing calculating methods, the present method has the following characteristics: (1) the constructed surface asperity is closer to the real asperity in contact, and the calculation of asperity parameters has better stability under different sampling intervals and (2) the contact pressure, contact area, and other contact parameters of the 3D rough surface are calculated with high accuracy and efficiency, and the calculation convergence is desirable. The reconstruction and contact analysis method of the 3D rough surface asperity proposed in this paper provides a more accurate reconstruction and calculation method for the study of contact fatigue life and wear failure of rough surfaces.

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