Circular Dynamic Stereoscopy and Its Application for Fluid Measurement

2004 ◽  
Vol 126 (1) ◽  
pp. 42-47
Author(s):  
Kikuhito Kawasue ◽  
Yuichiro Oya ◽  
Takakazu Ishimatsu
Keyword(s):  
High Speed ◽  
Tracer Particle ◽  
Three Dimensional ◽  
Image Plane ◽  
Positional Information ◽  
Video Camera ◽  
Measuring System ◽  
Original Position ◽  
Video Capture ◽  
Typical Application

By attaching a refractor to the lens of a Video Capture Device (e.g., CCD Video Camera) it is possible to record optical displacements from the original position of any object (tracer particle) within the image plane. If the refractor is physically rotated around the optical axis at high speed, the tracer particles create annular streaks due to the effect caused by the refractor’s circular shift. The perceived displacements are added to the image being recorded by the Video Capture Device (VCD). Additionally, these displacements are directly related to the distance between the VCD and the particle being measured: the magnitude of displacement on the image plane being inversely proportional to the distance between the VCD and point of measurement. Since the radius of each annular streak, of a point being measured, is inversely proportional to its distance from the VCD, it is therefore possible by analyzing these annular streaks, to determine the three dimensional positional information of the point. Thus the radius of the annular streaks on the image plane determines the z coordinate, while the geometric center provides the x and y coordinates. The theory and setup of such a measuring system is subsequently presented, and the measurement of a moving surface, such as moving water, is used to demonstrate a typical application of such a system.

Study on Magnetic Barrel Machine Equipped with Three-Dimensional Arrangement of Magnets

2007 ◽  
Vol 329 ◽  
pp. 761-766 ◽  
Author(s):  
Y. Zhang ◽  
Masato Yoshioka ◽  
Shin-Ichiro Hira
Keyword(s):  
High Speed ◽  
Permanent Magnets ◽  
Three Dimensional ◽  
Video Camera ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
The Media ◽  
Set Up

At present, a commercially available magnetic barrel machine equipped with permanent magnets has some faults arising from constructional reason. That is, grinding or finishing ability is different from place to place in the machining region, resulting in the limitation on the region we can use in the container of workpieces. Therefore, in this research, authors made the new magnetic barrel machine equipped with three dimensional (3D) magnet arrangement to overcome these faults. The grinding ability of the new 3D magnetic barrel machine converted was experimentally examined, and compared with that of the traditional magnetic barrel machine. As a result, it was shown that we can use much broader region in the new 3D machine. It was also shown that the grinding ability became higher. The distribution of barrel media in action was recorded by means of a high speed video camera. It was clarified that the media rose up higher and were distributed more uniformly in the container by the effect of the magnet block newly set up. It was supposed that this must be the reason for the above-mentioned improvement of grinding ability.

scholarly journals Investigation of Flow Behavior around Corotating Blades in a Double-Spindle Lawn Mower Deck

2005 ◽  
Vol 2005 (1) ◽  
pp. 77-89 ◽  
Author(s):  
W. Chon ◽  
R. S. Amano
Keyword(s):  
Flow Pattern ◽  
High Speed ◽  
Flow Behavior ◽  
Flow Analysis ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Video Camera ◽  
Sound Level ◽  
Lawn Mower ◽  
Level Meter

When the airflow patterns inside a lawn mower deck are understood, the deck can be redesigned to be efficient and have an increased cutting ability. To learn more, a combination of computational and experimental studies was performed to investigate the effects of blade and housing designs on a flow pattern inside a1.1mwide corotating double-spindle lawn mower deck with side discharge. For the experimental portion of the study, air velocities inside the deck were measured using a laser Doppler velocimetry (LDV) system. A high-speed video camera was used to observe the flow pattern. Furthermore, noise levels were measured using a sound level meter. For the computational fluid dynamics (CFD) work, several arbitrary radial sections of a two-dimensional blade were selected to study flow computations. A three-dimensional, full deck model was also developed for realistic flow analysis. The computational results were then compared with the experimental results.

scholarly journals Accuracy Assessment for the Three-Dimensional Coordinates by High-Speed Videogrammetric Measurement

2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Xianglei Liu ◽  
Yi Tang ◽  
Jing Ma
Keyword(s):  
High Speed ◽  
Accuracy Assessment ◽  
Three Dimensional ◽  
Shaking Table ◽  
Measuring System ◽  
Accuracy Analysis ◽  
Alternative Technique ◽  
Cmos Camera ◽  
Spatial Coordinates ◽  
Three Dimensional Coordinate

High-speed CMOS camera is a new kind of transducer to make the videogrammetric measurement for monitoring the displacement of high-speed shaking table structure. The purpose of this paper is to validate the three-dimensional coordinate accuracy of the shaking table structure acquired from the presented high-speed videogrammetric measuring system. In the paper, all of the key intermediate links are discussed, including the high-speed CMOS videogrammetric measurement system, the layout of the control network, the elliptical target detection, and the accuracy validation of final 3D spatial results. Through the accuracy analysis, the submillimeter accuracy can be made for the final the three-dimensional spatial coordinates which certify that the proposed high-speed videogrammetric technique is a better alternative technique which can replace the traditional transducer technique for monitoring the dynamic response for the shaking table structure.

Three-dimensional analysis of eye movements using four times high-speed video camera

2005 ◽  
Vol 32 (2) ◽  
pp. 107-112 ◽  
Author(s):  
Toshiaki Yagi ◽  
Yasuo Koizumi ◽  
Mio Aoyagi ◽  
Maki Kimura ◽  
Kazuki Sugizaki
Keyword(s):  
Eye Movements ◽  
Dimensional Analysis ◽  
High Speed ◽  
Three Dimensional ◽  
Video Camera ◽  
High Speed Video ◽  
High Speed Video Camera

A Dynamic Position Measurement Method for Destructive Process of Structures Using Image Processing

2004 ◽  
Author(s):  
Hiroshi Nishizawa ◽  
Satoshi Fujita ◽  
Osamu Furuya
Keyword(s):  
Image Processing ◽  
High Precision ◽  
High Speed ◽  
Spherical Surface ◽  
Three Dimensional ◽  
Measuring System ◽  
Position Measurement ◽  
Surface Emission ◽  
Optical Motion ◽  
Optical Motion Capture

In order to clarify the destruction mechanism of large structures in large seismic movements, a non-contacting displacement measurement system with a three-dimensional dynamic position with high precision is required. We have developed a three-dimensional measuring system with image processing using optical motion capture technology. This system consists of light emitting markers installed on the object structure and plural high speed cameras which obtain images of markers’ movement simultaneously, to measure the dynamic position of the three dimensional spatial coordinates of the markers. In order to measure the dynamic position with high precision, we have ever developed sub-pixel processing method which is able to measure very small displacements of the markers by analyzing the luminance distribution. Moreover, we have developed a new marker of spherical surface emission type which formed the luminance profile to improve furthermore the accuracy in rotational movement. Shaking tests were carried out with this measuring system and the results indicated that this system using new markers had sufficient accuracy within errors of a few millimeters in the structure of a 4 meter cube. Consequently, we have acquired the potential to apply to the measurement to the 3-D Full Scale Earthquake Testing Facility (E-Defense).

Simulation and experimental study of binder droplet infiltration in 3DP technology

2018 ◽  
Vol 32 (23) ◽  
pp. 1850272 ◽  
Author(s):  
Yuanyuan Wang ◽  
Pengfei Jia ◽  
Weidong Yang ◽  
Kai Peng ◽  
Sixiang Zhang
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Spherical Model ◽  
Ct Scanning ◽  
Video Camera ◽  
Nucleus Size ◽  
Digital Video Camera ◽  
Optimization Of Process Parameters ◽  
Industrial Ct ◽  
Droplet Infiltration

The purpose of this paper is to lessen the deviation of printing and to predict the nucleus size of binder droplet infiltration in three-dimensional printing (3DP) technology. The industrial CT is used to scan powders and the parameters of materials are calculated. A spherical model, which is based on the data from industrial CT scanning, predicts the nucleus size. The radius of the sphere is equal to the average radius of the sand particles. The spreading radius of binder droplet on the material is obtained by using the experimental method, and then the nucleus size is calculated by the equations. In order to do research on the process of droplet infiltration more intuitively, we analyze the effects of contact angle, porosity and drop height on the infiltration by using the software Comsol in the simulation. To verify the results of the simulation, the processes of infiltration are recorded by the high-speed digital video camera, and the nucleus size is observed by electron microscope. The study is important to conduct the infiltration experiments and provides a theoretical basis for optimization of process parameters in practical application.

Color Particle Image Velocimetry Improved by Decomposition of RGB Distribution Integrated in Depth Direction

2015 ◽  
Author(s):  
Yuichi Murai ◽  
Norio Yonezawa ◽  
Yoshihiko Oishi ◽  
Yuji Tasaka ◽  
Takeaki Yumoto
Keyword(s):  
High Speed ◽  
Vector Fields ◽  
Image Plane ◽  
Video Camera ◽  
Single View ◽  
Depth Direction ◽  
High Speed Video Camera ◽  
Image Velocimetry ◽  
Working Principle ◽  
Backward Analysis

A single-camera color PIV system based on the combination of a color-coded illumination and a color high-speed video camera has been developed. The system realizes flow velocity vector fields in multiple layers in the depth direction for a relatively wide volume. The working principle belongs to smoke-imaging PIV since particle per pixel is larger than unity in the digital image plane, which is different from the case of color 3-D PTV. The accuracy of the present color PIV depends on how the integral equation of color-signal overlapping among three wavelengths (R,G,B) is solved as inverse analysis. We propose in this paper a method to reasonably solve the equation, which removes color contamination in RGB sensors, and decomposes the color-illuminated smoke images into the smoke distributions inside individual layers. The first half of the paper deals with linear backward analysis for the color de-contamination to establish triple-layer velocimetry by a single-view imaging of smoke. Based on the success, we present in the second half an extended system that realizes simultaneous six-layer color PIV to which three intermediate colors are additionally illuminated into the measurement volume.

Cytoskeletal control of neuronal geometry: A serial EM analysis

1988 ◽  
Vol 46 ◽  
pp. 24-25
Author(s):  
John K. Stevens ◽  
Judy Trogadis
Keyword(s):  
High Resolution ◽  
High Speed ◽  
Three Dimensional ◽  
Video Camera ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Direct Role ◽  
Live Image ◽  
Neuronal Geometry ◽  
Rotation Stage

The cytoskeleton plays a direct role in controlling neurite shape. To quantitatively study both the three dimensional shape and the sub-micron structure of the cytoskeleton requires complete serial reconstruction at the Electron Microscopic level. We have devised a computer reconstruction system specifically for this purpose.The system uses a 35mm film copy of 3.25 x 4.00 inch EM negative as the data source. The film is placed into a high speed film transport (15 frames/second), which is mounted on a X,Y and rotation stage controlled by stepping motors. The 35mm film is viewed through a stepping motor controlled zoom lens mounted on a high resolution (1119 x 1024) video camera. A high resolution frame grabber controlled by the computer can store one complete frame. Thus, the live image and a stored image may be displayed alternately on a high resolution monitor. Finally, a graphics overlay and mouse connected to the computer can be used to align successive sections via the stepping motors, as well as to trace the outlines of a profile, or of a microtubule.

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