Modified 2-1/2-D visual servo-based determination of next best views in automatic 3D reconstruction

2014 ◽  
Author(s):  
L. Zhang ◽  
J.Q. Zuo ◽  
L.P. Huang ◽  
X.G. Zhang ◽  
L.G. Shuai ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Visual Servo

scholarly journals Determination of Split Renal Function by 3D Reconstruction of CT Angiograms: A Comparison with Gamma Camera Renography

2008 ◽  
Vol 191 (5) ◽  
pp. 1552-1558 ◽  
Author(s):  
Adam L. Summerlin ◽  
Mark E. Lockhart ◽  
Andrew M. Strang ◽  
Peter N. Kolettis ◽  
Naomi S. Fineberg ◽  
...  
Keyword(s):  
Renal Function ◽  
3D Reconstruction ◽  
Gamma Camera ◽  
Split Renal Function ◽  
Gamma Camera Renography

A robot visual servo-based approach to the determination of next best views

2015 ◽  
Author(s):  
Lei Zhang ◽  
Junqiu Zuo ◽  
Xingtian Yao ◽  
Xingguo Zhang ◽  
Liguo Shuai
Keyword(s):  
Visual Servo

scholarly journals Environment Perception Technologies for Power Transmission Line Inspection Robots

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Minghao Chen ◽  
Yunong Tian ◽  
Shiyu Xing ◽  
Zhishuo Li ◽  
En Li ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Object Detection ◽  
Transmission Line ◽  
Power Transmission ◽  
Three Dimensional ◽  
Power Transmission Line ◽  
Visual Servo ◽  
Environment Perception ◽  
Control Technologies ◽  
Inspection Robots

With the fast development of the power system, traditional manual inspection methods of a power transmission line (PTL) cannot supply the demand for high quality and dependability for power grid maintenance. Consequently, the automatic PTL inspection technology becomes one of the key research focuses. For the purpose of summarizing related studies on environment perception and control technologies of PTL inspection, technologies of three-dimensional (3D) reconstruction, object detection, and visual servo of PTL inspection are reviewed, respectively. Firstly, 3D reconstruction of PTL inspection is reviewed and analyzed, especially for the technology of LiDAR-based reconstruction of power lines. Secondly, the technology of typical object detection, including pylons, insulators, and power line accessories, is classified as traditional and deep learning-based methods. After that, their merits and demerits are considered. Thirdly, the progress and issues of visual servo control of inspection robots are also concisely addressed. For improving the automation degree of PTL robots, current problems of key techniques, such as multisensor fusion and the establishment of datasets, are discussed and the prospect of inspection robots is presented.

3D Reconstruction of Single Particles by Quasi-Conical Tilting from Micrographs Recorded with Dynamic Focusing

1990 ◽  
Vol 48 (1) ◽  
pp. 244-245
Author(s):  
D. Typke ◽  
G. Pfeifer ◽  
R. Hegerl ◽  
W. Baumeister
Keyword(s):  
3D Reconstruction ◽  
Narrow Slit ◽  
Single Particles ◽  
Straight Line Parallel ◽  
Straight Line ◽  
Small Spot ◽  
Line Parallel ◽  
Illuminating Beam ◽  
Selection Of

The method of quasi-conical tilting for the 3D reconstruction of single macromolecules utilizes the fact that particles tend to adsorb to the supporting film in a few preferred orientations, though with arbitrary azimuthal angles. Therefore, a single electron micrograph of a tilted specimen containing a large number of particle projections provides the data of a conical tilt series with projection directions distributed randomly on a cone. For the selection of particles of equal orientation with respect to the supporting film and for the determination of their azimuth angles, a zero tilt image taken after the minimum dose “tilt image” is utilized.A disadvantage of the method is the large focal range of the tilt image, which e.g. at 30,000× magnification exceeds 5 μm. This, however, can be overcome by small-spot illumination in conjunction with dynamic focusing. For this, the illuminating beam is reduced to a diameter of 50-200 nm, and shifted stepwise or continuously over the object; for each spot position the focus is properly adjusted. Thus the focus range of the whole image is restricted to that of a single spot. Another way to realize dynamic focusing of a tilted object is the use of a narrow slit aperture in the condenser C2, thus illuminating a straight line parallel to the tilt axis.

scholarly journals MATLAB Simulation Environment for Estimating the Minimal Number and Positions of Cameras for 3D Surface Reconstruction in a Fully-Digital Surgical Microscope

2018 ◽  
Vol 4 (1) ◽  
pp. 517-520 ◽  
Author(s):  
Andreas Wachter ◽  
Jan Kost ◽  
Werner Nahm
Keyword(s):  
Optical Properties ◽  
3D Reconstruction ◽  
3D Model ◽  
Observation System ◽  
Simulation Environment ◽  
Matlab Simulation ◽  
Surgical Microscope ◽  
Camera Array ◽  
Current Observation

AbstractContemporary surgical microscope systems have excellent optical properties but some desirable features remain unavailable. The number of co-observers is currently restricted, by spatial and optical limitations, to only two. Moreover, ergonomics poses are a problem: Current microscope systems impede free movement and sometimes demand that surgeons take uncomfortable postures over long periods of time. To rectify these issues, some companies developed surgical microscope systems based on a streaming approach. These systems remove some of the limitations. Multi-observer positions, for example, are not independent from each other, for example. In order to overcome the aforementioned limitations, we are currently developing an approach for the next generation of surgical microscope: Namely the fully digital surgical microscope, where the current observation system is replaced with a camera array, allowing real-time 3D reconstruction of surgical scenes and, consequently, the rendering of almost unlimited views for multiple observers. These digital microscopes could make the perspective through the microscope unnecessary allowing the surgeon to move freely and work in more comfortable postures. The requirements on the camera array in such a system have to be determined. For this purpose, we propose of estimation the minimal number of cameras and their positions needed for the 3D reconstruction of microsurgical scenes. The method of estimation is based on the requirements for the 3D reconstruction. Within the MATLAB simulation environment, we have developed a 3D model of a microsurgical scene, used for the determination of the number of required cameras. In a next step a small, compact and costefficient system with few opto-mechanical components could be manufactured.

scholarly journals Application of a high-throughput microcrystal delivery system to serial femtosecond crystallography

2020 ◽  
Vol 53 (2) ◽  
pp. 477-485 ◽  
Author(s):  
Donghyeon Lee ◽  
Sehan Park ◽  
Keondo Lee ◽  
Jangwoo Kim ◽  
Gisu Park ◽  
...  
Keyword(s):  
Proteinase K ◽  
Target System ◽  
Visual Servo ◽  
Fixed Target ◽  
Delivery Methods ◽  
Advanced Technique ◽  
One Dimensional ◽  
Novel Technique ◽  
Serial Femtosecond Crystallography

Microcrystal delivery methods are pivotal in the use of serial femtosecond crystallography (SFX) to resolve the macromolecular structures of proteins. Here, the development of a novel technique and instruments for efficiently delivering microcrystals for SFX are presented. The new method, which relies on a one-dimensional fixed-target system that includes a microcrystal container, consumes an extremely low amount of sample compared with conventional two-dimensional fixed-target techniques at ambient temperature. This novel system can deliver soluble microcrystals without highly viscous carrier media and, moreover, can be used as a microcrystal growth device for SFX. Diffraction data collection utilizing this advanced technique along with a real-time visual servo scan system has been successfully demonstrated for the structure determination of proteinase K microcrystals at 1.85 Å resolution.

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