scholarly journals Different activation signatures in the primary sensorimotor and higher-level regions for haptic three-dimensional curved surface exploration

NeuroImage ◽  
2021 ◽  
Vol 231 ◽  
pp. 117754
Author(s):  
Jiajia Yang ◽  
Peter J. Molfese ◽  
Yinghua Yu ◽  
Daniel A. Handwerker ◽  
Gang Chen ◽  
...  
2014 ◽  
Vol 490-491 ◽  
pp. 600-606
Author(s):  
Jie Qiong Lin ◽  
Jin Guo Han ◽  
Dan Jing ◽  
Xian Jing

Elliptical vibration cutting (EVC) process and three dimensional cutting surfaces are analyzed in this paper to understand the formation of surface topography. The model of EVC surface topography is established based on curved surface remove function under the assumption that the tool edge is sharp enough. And simulation analysis of surface topography is conducted with different feed offset ratios. Results indicate that RMS change with feed offset ratios λ. The range of RMS is larger when feed offset ratio ranges from both 0 to 0.4 and 0.6 to 1, while the range is smaller when feed offset ratio changes from 0.4 to 0.6. Whats more, RMS reaches the minimum when feed offset ratio is 0.5. The present research provides some references for reducing the height of vibration ripples and improving EVC surface quality.


2008 ◽  
Vol 392-394 ◽  
pp. 151-155
Author(s):  
Tong Wang ◽  
K. Jiang ◽  
Shu Qiang Xie ◽  
Shuang Shuang Hao

In this paper, the characteristics and general laws of cutting complex curved surface by wire electrical discharge machining (WEDM) system are studied. Based on analysis of motion parameters the universal mathematical model of polar coordinates is derived. Moreover, the simulation of WEDM system is introduced, which is carried out by using language Visual C++ and the three dimensional graph software OpenGL.This simulation method is helpful in improving machining quality and productivity of complex curved surfaces, and is fundation for establishing CAD/CAPP/CAM technology in WEDM.


2014 ◽  
Vol 628 ◽  
pp. 205-208
Author(s):  
Gui Jie Fan

The impeller blades are hard to machine for its complex and curved surface structures. It is almost impossible to manufacture the blades by manual programming on Numerical Control Tool. Now, the program almost is completed by the three-dimensional CAD/ CAM software, such as UG, Pro/Engineer, CimatronE which have a lot of machining strategies suitable for a wide variety of parts. However, the result is not perfect if you choose improper strategies. Even more, machining marks will be left on the parts’ surface. This paper takes the impeller for an example and gives the solutions for eliminating machining marks left on the impeller blades’ surface through a comparative analysis on the 3-axis finish machining strategies in CimatronE.


1996 ◽  
Vol 33 (3) ◽  
pp. 245-251 ◽  
Author(s):  
Katsuaki Mishima ◽  
Toshio Sugahara ◽  
Yoshihide Mori ◽  
Masayoshi Sakuda

A three-dimensional measuring system was developed to analyze changes in palatal forms of UCLP infants. This system quantified the change of the curved surface on a palate by automatically superimposing two wireframe models obtained from casts at different stages of growth. It also analyzed the curvature of the palatal surface. This system was used to study the palates of 20 infants with unilateral cleft lip and palate (UCLP), from the first to fourth months after birth (12 with Hotz's plate and 8 without, selected at random). Both major and lesser maxillary segments without Hotz's plate remained anterior and lateral although those with Hotz's plate moved mesially during the fourth month after birth. In addition, the degrees of curvature on the palatal surfaces with Hotz's plate were less than those without Hotz's plate.


2020 ◽  
Vol 12 (4) ◽  
pp. 168781402091602
Author(s):  
Honggen Zhou ◽  
Jie Cui ◽  
Guizhong Tian ◽  
Yesheng Zhu ◽  
Changfeng Jia

The drag reduction mechanism of puffer epidermis was closely related to its real geometry. In order to solve the modeling problem of epidermal spines on the puffer surface, a modeling method for the expansion of puffer shape was proposed. The three-dimensional scanning and non-uniform rational B-spline surface modeling technology was used to reconstruct the puffer model. According to the curvature characteristics, the surface mathematical equations including exponential, logarithmic, and sinusoidal functions were established based on the multinomial function. The surface was generated by a mathematical equation, and the surface was divided into several non-uniform rational B-spline patches according to curvature. After discretization, the point cloud Gaussian curvature and average value were calculated based on the implicit equation of moving least square surface, and whether the surface is approximately extensible or not was judged. Finally, the puffer surface was divided into 46 curved patches. In this article, the surface expansion algorithm gave priority to ensure the area unchanged, and four feature surfaces were selected according to the epidermal spines arrangement of the puffer surface. The results showed that the technique can simply and efficiently unfold the curved surface of the puffer fish, thus the mapping relationship between the epidermal spines on the surface and the plane was determined, which established a foundation for the accurate arrangement and modeling of the epidermal spines on the surface.


2020 ◽  
Author(s):  
Taku Sakamoto ◽  
Ichiro Oda ◽  
Takuma Okamura ◽  
Hourin Cho ◽  
Satoru Nonaka ◽  
...  

Abstract Accurate measurement of the distance between any two points under endoscopic examination of the gastrointestinal tract is difficult due to the fisheye lens currently used on endoscopes. To overcome this issue, we developed a three-dimensional visual inspection system that incorporates a phase-shift method for direct measurement of a three-dimensional shape. Projection of a striped pattern is used to enable three-dimensional renderings of a surface using an industrial camera. We evaluated the accuracy of measurement relative to that of reference measurements obtained using a measurement microscope, for three-dimensional shapes on a plane and curved surface. For 60 regions of interests, with various configurations of the reference locations relative to the camera, the measurement error for our system was <0.1 mm on the plane grid and <0.5 mm on the curved surface. The accuracy of our novel three-dimensional visual inspection system could improve determination of the size of lesions with different shapes, flat or depressed, regardless of the curved surface of the gastrointestinal tract.


1996 ◽  
Vol 33 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Katsuaki Mishima ◽  
Toshio Sugahara ◽  
Yoshihide Mori ◽  
Masayoshi Sakuda

A three-dimensional measuring system was developed to analyze changes in palatal forms of UCLP infants. This system quantified the change of the curved surface on a palate by automatically superimposing two wireframe models obtained from casts at different stages of growth. It also analyzed the curvature of the palatal surface. This system was used to study the palates of 20 infants with unilateral cleft tip and palate (UCLP), from the first to fourth months after birth (12 with Hotz's plate and 8 without, selected at random). Both major and lesser maxillary segments without Hotz's plate remained anterior and lateral although those with Hotz's plate moved mesially during the fourth month after birth. In addition, the degrees of curvature on the palatal surfaces with Hotz's plate were less than those without Hotz's plate.


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