High voltage line distance measurement and position detection based on stereoscopic image

2018 ◽  
Author(s):  
Pawel Kowalski ◽  
Maciej Czyzak
Keyword(s):  
High Voltage ◽  
Distance Measurement ◽  
Stereoscopic Image ◽  
Position Detection

scholarly journals Obstacle distance measurement based on binocular vision for high-voltage transmission lines using a cable inspection robot

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042093691
Author(s):  
Le Huang ◽  
Gongping Wu ◽  
Jiayang Liu ◽  
Song Yang ◽  
Qi Cao ◽  
...  
Keyword(s):  
High Voltage ◽  
Binocular Vision ◽  
Transmission Lines ◽  
Distance Measurement ◽  
Estimation Accuracy ◽  
Depth Information ◽  
Disparity Map ◽  
Inspection Robot ◽  
High Voltage Transmission ◽  
Inspection Robots

Obstacle distance measurement is one of the key technologies for cable inspection robots on high-voltage transmission lines. This article develops a novel method based on binocular vision for extracting the feature points of images and reconstructing 3D scenes. The proposed method seamlessly incorporates camera calibration, dense stereo matching, and 3D reconstruction. We apply a novel calibration method to acquire intrinsic and extrinsic parameters and use an improved Semi-Global Matching (SGM) algorithm based on the least squares fitting interpolation to refine the basic disparity map. Based on the depth information of the optimized disparity map and the principle of binocular vision measurement, a model is established to estimate the distance of an obstacle from the cable inspection robot. Extensive experiments show that the proposed method achieves an estimation accuracy of less than 5% from 0.5 m to 5.0 m, offering extremely high distance estimation accuracy and robustness. The study improves the autonomy and intelligence of inspection robots used in the power industry.

High Voltage Electron Microscopy of Ion-Milled Dental Enamel

1974 ◽  
Vol 32 ◽  
pp. 60-61
Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Third Molar ◽  
Polarized Light ◽  
Dental Enamel ◽  
Longitudinal Section ◽  
Ion Milling ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.

Three-Dimensional Visualization of the T-System of Frog Muscle Using High Voltage Electron Microscopy and a Lanthanum Stain

1977 ◽  
Vol 35 ◽  
pp. 570-571 ◽  
Author(s):  
Lee D. Peachey ◽  
Clara Franzini-Armstrong
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Three Dimensional ◽  
Biological Tissues ◽  
High Voltage Electron Microscopy ◽  
Transverse Tubular System ◽  
Peroxidase Reaction ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
T System

The effective study of biological tissues in thick slices of embedded material by high voltage electron microscopy (HVEM) requires highly selective staining of those structures to be visualized so that they are not hidden or obscured by other structures in the image. A tilt pair of micrographs with subsequent stereoscopic viewing can be an important aid in three-dimensional visualization of these images, once an appropriate stain has been found. The peroxidase reaction has been used for this purpose in visualizing the T-system (transverse tubular system) of frog skeletal muscle by HVEM (1). We have found infiltration with lanthanum hydroxide to be particularly useful for three-dimensional visualization of certain aspects of the structure of the T- system in skeletal muscles of the frog. Specifically, lanthanum more completely fills the lumen of the tubules and is denser than the peroxidase reaction product.

Resolution, Contrast and Interpretation of HVEM Images of Crystals

1973 ◽  
Vol 31 ◽  
pp. 228-229
Author(s):  
L. E. Thomas ◽  
J. S. Lally ◽  
R. M. Fisher
Keyword(s):  
High Voltage ◽  
Chromatic Aberration ◽  
Crystalline Materials ◽  
Resolution Parameter ◽  
Instrument Resolution ◽  
Imaging Conditions ◽  
Beam Excitation ◽  
Optimum Imaging

In addition to improved penetration at high voltage, the characteristics of HVEM images of crystalline materials are changed markedly as a result of many-beam excitation effects. This leads to changes in optimum imaging conditions for dislocations, planar faults, precipitates and other features.Resolution - Because of longer focal lengths and correspondingly larger aberrations, the usual instrument resolution parameter, CS174 λ 374 changes by only a factor of 2 from 100 kV to 1 MV. Since 90% of this change occurs below 500 kV any improvement in “classical” resolution in the MVEM is insignificant. However, as is widely recognized, an improvement in resolution for “thick” specimens (i.e. more than 1000 Å) due to reduced chromatic aberration is very large.

Radiation-Induced Precipitation at Thin Foil Surfaces in Ni-Be Alloys

1982 ◽  
Vol 40 ◽  
pp. 598-599
Author(s):  
T. Mukai ◽  
T. E. Mitchell
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Electron Irradiation ◽  
High Vacuum ◽  
Thin Foil ◽  
Homogeneous Precipitation ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Radiation Induced

Radiation-induced homogeneous precipitation in Ni-Be alloys was recently observed by high voltage electron microscopy. A coupling of interstitial flux with solute Be atoms is responsible for the precipitation. The present investigation further shows that precipitation is also induced at thin foil surfaces by electron irradiation under a high vacuum.

The Reduction of Chromatic Aberrations Due to Instrumental Instabilities

1971 ◽  
Vol 29 ◽  
pp. 14-15
Author(s):  
J. S. Lally ◽  
R. Evans
Keyword(s):  
Electron Microscope ◽  
High Voltage ◽  
Focal Length ◽  
Chromatic Aberration ◽  
Objective Lens ◽  
Usual Practice ◽  
Voltage Electron ◽  
Short Focal Length ◽  
Chromatic Aberrations ◽  
Electron Microscopes

One of the instrumental factors often limiting the resolution of the electron microscope is image defocussing due to changes in accelerating voltage or objective lens current. This factor is particularly important in high voltage electron microscopes both because of the higher voltages and lens currents required but also because of the inherently longer focal lengths, i.e. 6 mm in contrast to 1.5-2.2 mm for modern short focal length objectives.The usual practice in commercial electron microscopes is to design separately stabilized accelerating voltage and lens supplies. In this case chromatic aberration in the image is caused by the random and independent fluctuations of both the high voltage and objective lens current.

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