Three-dimensional positioning method for moving particles based on defocused imaging using single-lens dual-camera system

2016 ◽  
Vol 14 (3) ◽  
pp. 031201-31205 ◽  
Author(s):  
Wu Zhou Wu Zhou ◽  
Na Jin Na Jin ◽  
Minhua Jia Minhua Jia ◽  
Huinan Yang Huinan Yang ◽  
and Xiaoshu Cai and Xiaoshu Cai
Keyword(s):  
Three Dimensional ◽  
Camera System ◽  
Single Lens ◽  
Positioning Method ◽  
Defocused Imaging

scholarly journals Application of 3D Image Technology in Motor and Sensory Nerve Classification

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Na Liu
Keyword(s):  
Peroneal Nerve ◽  
Three Dimensional ◽  
Sensory Nerve ◽  
Digital Camera ◽  
Histochemical Staining ◽  
Dimensional Structure ◽  
3D Image ◽  
Three Dimensional Reconstruction ◽  
Camera System ◽  
Dimensional Reconstruction

Objective. To explore the application of 3D image technology in motor and sensory nerve classification. Methods. A total of 200 sections of the 5cm-long popliteal fossa peroneal nerve from adult volunteers were cut and frozen. The slices were 10 m thick, and the interval between the slices was 0.25 mm. Acetylcholinesterase histochemical staining was used to observe the changes of nerve bundles under the microscope. The stained sections were transformed into digital images by the digital camera system, and the images were stitched to obtain a two-dimensional panoramic image 100 times magnified. The properties of the functional bundles were manually judged. Using Amira 3.1 three‐dimensional reconstruction software to realize the three-dimensional reconstruction and visualization of nerve can not only accurately perceive the complex three-dimensional surface structure of nerve, but also arbitrarily display, rotate, scale, and segment the three-dimensional structure inside nerve, and carry out three-dimensional measurement in time. It has made preliminary achievements in brachial plexus, lumbosacral plexus, neural stem functional bundle (group), and intramuscular nerve routing and distribution, including the regeneration process of sensory nerve and three-dimensional reconstruction and visualization of composite tissue containing sensory nerve. Conclusion. Based on histology and computer technology, the functional band of short peroneal nerve can be reconstructed in 3D, which provides a feasible basis for the three-dimensional reconstruction of the functional band of the long peripheral nerve.

scholarly journals RECONSTRUCTION OF INDOOR MODELS USING POINT CLOUDS GENERATED FROM SINGLE-LENS REFLEX CAMERAS AND DEPTH IMAGES

2015 ◽  
Vol XL-4/W5 ◽  
pp. 99-102
Author(s):  
F. Tsai ◽  
T.-S. Wu ◽  
I.-C. Lee ◽  
H. Chang ◽  
A. Y. S. Su
Keyword(s):  
Data Processing ◽  
Data Acquisition ◽  
Three Dimensional ◽  
Point Clouds ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Indoor Environments ◽  
Single Lens ◽  
Processing Procedure ◽  
Data Processing Procedure

This paper presents a data acquisition system consisting of multiple RGB-D sensors and digital single-lens reflex (DSLR) cameras. A systematic data processing procedure for integrating these two kinds of devices to generate three-dimensional point clouds of indoor environments is also developed and described. In the developed system, DSLR cameras are used to bridge the Kinects and provide a more accurate ray intersection condition, which takes advantage of the higher resolution and image quality of the DSLR cameras. Structure from Motion (SFM) reconstruction is used to link and merge multiple Kinect point clouds and dense point clouds (from DSLR color images) to generate initial integrated point clouds. Then, bundle adjustment is used to resolve the exterior orientation (EO) of all images. Those exterior orientations are used as the initial values to combine these point clouds at each frame into the same coordinate system using Helmert (seven-parameter) transformation. Experimental results demonstrate that the design of the data acquisition system and the data processing procedure can generate dense and fully colored point clouds of indoor environments successfully even in featureless areas. The accuracy of the generated point clouds were evaluated by comparing the widths and heights of identified objects as well as coordinates of pre-set independent check points against in situ measurements. Based on the generated point clouds, complete and accurate three-dimensional models of indoor environments can be constructed effectively.

Research on a Method of EDM Control System Based on Two Positioning Mode

2012 ◽  
Vol 580 ◽  
pp. 180-184
Author(s):  
Xiao Liang Huang ◽  
Yong Jiang Luo ◽  
Hai Bo Lin ◽  
San Zhang
Keyword(s):  
Control Function ◽  
Three Dimensional ◽  
Step Motor ◽  
Dimensional Structure ◽  
Micro Edm ◽  
Basic Performance ◽  
Positioning Method ◽  
Rolling Guide ◽  
Accuracy And Repeatability ◽  
Strong Control

The processing of three-dimensional structure and servo feed systems for micro-EDM have strict requirements.The two positioning method is used to solve the contradiction between the large stroke and high precision, Coarse and fine action units matched to achieve the precision positioning requirements. A combined device with piezoelectric ceramic and step motor has been employed as drive and use the linear rolling guide As the transmission in this study,which has strong control function ，great flexibility, high positioning accuracy and repeatability. The basic performance of the platform met the needs of micro-EDM control.

scholarly journals Magnetic Positioning Technique Integrated with Near-Field Communication for Wireless EV Charging

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1081 ◽  
Author(s):  
Zhongnan Qian ◽  
Rui Yan ◽  
Zeqian Cheng ◽  
Jiande Wu ◽  
Xiangning He
Keyword(s):  
Relative Position ◽  
Data Transmission ◽  
Power Efficiency ◽  
Near Field ◽  
Three Dimensional ◽  
Secondary Coil ◽  
Power Transfer ◽  
Electric Vehicle Charging ◽  
Position Detection ◽  
Positioning Method

For wireless electric vehicle charging, the relative position of the primary and secondary coils has significant impacts on the transferred power, efficiency and leakage magnetic flux. In this paper, a magnetic positioning method using simultaneous power and data transmission (SWPDT) is proposed for power coil alignment. Four signal coils are installed on the primary coil to detect the secondary coil position. By measuring the positioning signal amplitudes from the four signal coils, the power coil relative position can be obtained. Moreover, all the communication needed in the positioning process can be satisfied well by SWPDT technology, and no extra radio frequency (RF) communication hardware is needed. The proposed positioning method can work properly both in power transfer online condition and in power transfer offline condition. Thus, a highly integrated wireless charging system is achieved, which features simultaneous power transfer, data transmission and position detection. A positioning experimental setup is built to verify the proposed method. The experimental results demonstrate that the positioning resolution can be maintained no lower than 1 cm in a 1060 mm × 900 mm elliptical region for a pair of 510 mm × 410 mm rectangular power coils. The three-dimensional positioning accuracy achieves up to 1 cm.

scholarly journals The Use of Gigapixel Photogrammetry for the Understanding of Landslide Processes in Alpine Terrain

Geosciences ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 99 ◽  
Author(s):  
Saverio Romeo ◽  
Lucio Di Matteo ◽  
Daniel Kieffer ◽  
Grazia Tosi ◽  
Aurelio Stoppini ◽  
...  
Keyword(s):  
3D Model ◽  
Low Cost ◽  
Three Dimensional ◽  
Image Sequences ◽  
Synthetic Aperture ◽  
Synthetic Aperture Radar Interferometry ◽  
Experimental Application ◽  
Single Lens ◽  
Landslide Processes ◽  
3D Information

The work in this paper illustrates an experimental application for geosciences by coupling new and low cost photogrammetric techniques: Gigapixel and Structure-from-Motion (SfM). Gigapixel photography is a digital image composed of billions of pixels (≥1000 megapixels) obtained from a conventional Digital single-lens reflex camera (DSLR), whereas the SfM technique obtains three-dimensional (3D) information from two-dimensional (2D) image sequences. The field test was carried out at the Ingelsberg slope (Bad Hofgastein, Austria), which hosts one of the most dangerous landslides in the Salzburg Land. The stereographic analysis carried out on the preliminary 3D model, integrated with Ground Based Synthetic Aperture Radar Interferometry (GBInSAR) data, allowed us to obtain the main fractures and discontinuities of the unstable rock mass.

scholarly journals A Methodology for Multi-Camera Surface-Shape Estimation of Deformable Unknown Objects

Robotics ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 69 ◽  
Author(s):  
Evgeny Nuger ◽  
Beno Benhabib
Keyword(s):  
Particle Filtering ◽  
Surface Deformation ◽  
Vision System ◽  
Three Dimensional ◽  
Target Object ◽  
Surface Shape ◽  
Shape Estimation ◽  
Formal Approach ◽  
Camera System ◽  
Unknown Objects

A novel methodology is proposed herein to estimate the three-dimensional (3D) surface shape of unknown, markerless deforming objects through a modular multi-camera vision system. The methodology is a generalized formal approach to shape estimation for a priori unknown objects. Accurate shape estimation is accomplished through a robust, adaptive particle filtering process. The estimation process yields a set of surface meshes representing the expected deformation of the target object. The methodology is based on the use of a multi-camera system, with a variable number of cameras, and range of object motions. The numerous simulations and experiments presented herein demonstrate the proposed methodology’s ability to accurately estimate the surface deformation of unknown objects, as well as its robustness to object loss under self-occlusion, and varying motion dynamics.

Blink-Spot Projection Method for Fast Three-Dimensional Shape Measurement

2015 ◽  
Vol 27 (4) ◽  
pp. 430-443 ◽  
Author(s):  
Jun Chen ◽  
◽  
Qingyi Gu ◽  
Tadayoshi Aoyama ◽  
Takeshi Takaki ◽  
...  
Keyword(s):  
Projection Method ◽  
Fast Moving ◽  
High Speed ◽  
Degrees Of Freedom ◽  
Moving Objects ◽  
Three Dimensional ◽  
Frame Rate ◽  
Light Illumination ◽  
Camera System ◽  
3D Shape

<div class=""abs_img""> <img src=""[disp_template_path]/JRM/abst-image/00270004/13.jpg"" width=""300"" /> Blink-spot projection method</div> We present a blink-spot projection method for observing moving three-dimensional (3D) scenes. The proposed method can reduce the synchronization errors of the sequential structured light illumination, which are caused by multiple light patterns projected with different timings when fast-moving objects are observed. In our method, a series of spot array patterns, whose spot sizes change at different timings corresponding to their identification (ID) number, is projected onto scenes to be measured by a high-speed projector. Based on simultaneous and robust frame-to-frame tracking of the projected spots using their ID numbers, the 3D shape of the measuring scene can be obtained without misalignments, even when there are fast movements in the camera view. We implemented our method with a high-frame-rate projector-camera system that can process 512 × 512 pixel images in real-time at 500 fps to track and recognize 16 × 16 spots in the images. Its effectiveness was demonstrated through several 3D shape measurements when the 3D module was mounted on a fast-moving six-degrees-of-freedom manipulator. </span>

Digital Three-Dimensional Photogrammetry: Evaluation of Anthropometric Precision and Accuracy Using a Genex 3D Camera System

2004 ◽  
Vol 41 (5) ◽  
pp. 507-518 ◽  
Author(s):  
Seth M. Weinberg ◽  
Nicole M. Scott ◽  
Katherine Neiswanger ◽  
Carla A. Brandon ◽  
Mary L. Marazita
Keyword(s):  
Three Dimensional ◽  
Measurement Precision ◽  
Camera System ◽  
Research Designs ◽  
3D Camera ◽  
3D Photogrammetry ◽  
Precision And Accuracy ◽  
Almost All ◽  
Good Congruence ◽  
Better Than

Objective To determine the precision and accuracy of facial anthropometric measurements obtained through digital three-dimensional (3D) photogrammetry. Design Nineteen standard craniofacial measurements were repeatedly obtained on 20 subjects by two independent observers, using calipers and 3D photos (obtained with a Genex 3D camera system), both with and without facial landmarks labeled. Four different precision estimates were then calculated and compared statistically across techniques. In addition, mean measurements from 3D photos were compared statistically with those from direct anthropometry. Results In terms of measurement precision, the 3D photos were clearly better than direct anthropometry. In almost all cases, the 3D photo with landmarks labeled had the highest overall precision. In addition, labeling landmarks prior to taking measurements improved precision, regardless of method. Good congruence was observed between means derived from the 3D photos and direct anthropometry. Statistically significant differences were noted for seven measurements; however, the magnitude of these differences was often clinically insignificant (< 2 mm). Conclusions Digital 3D photogrammetry with the Genex camera system is sufficiently precise and accurate for the anthropometric needs of most medical and craniofacial research designs.

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