scholarly journals Assessing MMA Welding Process Stability Using Machine Vision-Based Arc Features Tracking System

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 84
Author(s):  
Wojciech Jamrozik ◽  
Jacek Górka
Keyword(s):  
Tracking System ◽  
Welding Process ◽  
Reference Value ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Mma Welding ◽  
Arc Length ◽  
Process Stability ◽  
Geometrical Properties ◽  
Arc Voltage

Arc length is a crucial parameter of the manual metal arc (MMA) welding process, as it influences the arc voltage and the resulting welded joint. In the MMA method, the process’ stability is mainly controlled by the skills of a welder. According to that, giving the feedback about the arc length as well as the welding speed to the welder is a valuable property at the stage of weld training and in the production of welded elements. The proposed solution is based on the application of relatively cheap Complementary Metal Oxide Semiconductor (CMOS) cameras to track the welding electrode tip and to estimate the geometrical properties of welding arc. All measured parameters are varying during welding. To validate the results of image processing, arc voltage was measured as a reference value describing in some part the process stability.

scholarly journals Synchronic Fuzzy Control of Master and Slave Arc in Twin-Wire Pulsed Metal Active Gas Welding

2011 ◽  
Vol 2-3 ◽  
pp. 69-73
Author(s):  
Kuan Fang He ◽  
Ji Gang Wu ◽  
Si Wen Xiao
Keyword(s):  
Fuzzy Control ◽  
Correction Factor ◽  
Fuzzy Logic Controller ◽  
Welding Process ◽  
Arc Length ◽  
Arc Voltage ◽  
Base Time ◽  
Feeding Speed ◽  
Wire Feeding ◽  
The Stability

This research aims at the retention of the stability of arcs in twin-arc pulsed metal active gas welding process. That is, a correction-factor fuzzy logic controller (FLC) is designed to keep the stability of arcs of twin-arcs pulsed metal active gas welding (MAG) process. In the controller, the peak arc voltage of the master welding power is controlled by the pulse base time with means of feed back of arc voltage. The peak arc voltage of slave welding power is controlled by the wire feeding speed with means of feed back of peak arc voltage. The adjusting fuzzy control rule with correction factor is introduced to design for controlling rule and table, and the FLC is realized in a Look-Up-Table (LUT) method. With the controller, the arc length can be kept stable in welding process. Experimental results are provided to confirm the effectiveness of this approach.

Visual tracking of a moving person for a home robot

2005 ◽  
Vol 219 (4) ◽  
pp. 259-269 ◽  
Author(s):  
Kai-Tai Song ◽  
Chen-Chu Chlen
Keyword(s):  
Visual Tracking ◽  
Tracking System ◽  
Processing System ◽  
Digital Signal ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Human Face ◽  
Web Camera ◽  
Robot Head ◽  
Home Robot

This paper presents a visual tracking system for a home robot to pursue a person. The system works by detecting a human face and tracking a person via controlling a two-degree-of-freedom robot head and the robot body. An image processing system has been developed to extract facial features using a complementary metal-oxide semiconductor (CMOS) web camera. An algorithm is proposed to recognize a human face by using skin colour and elliptical edge information of a human face. A digital signal processing (DSP)-based motor control card is designed and implemented for robot motion control. The visual tracking control system has been integrated on a self-constructed prototype home robot. Experimental results show that the robot tracks a person in real-time.

scholarly journals Analysis of the Covered Electrode Welding Process Stability on the Basis of Linear Regression Equation

2014 ◽  
Vol 59 (3) ◽  
pp. 905-909
Author(s):  
J. Słania ◽  
B. Ślązak
Keyword(s):  
Linear Regression ◽  
Welding Process ◽  
Welding Current ◽  
Process Stability ◽  
Arc Voltage ◽  
Welding Arc ◽  
Instantaneous Values ◽  
Welding Properties ◽  
The Impact ◽  
Coated Electrodes

Abstract The article presents the process of production of coated electrodes and their welding properties. The factors concerning the welding properties and the currently applied method of assessing are given. The methodology of the testing based on the measuring and recording of instantaneous values of welding current and welding arc voltage is discussed. Algorithm for creation of reference data base of the expert system is shown, aiding the assessment of covered electrodes welding properties. The stability of voltage–current characteristics was discussed. Statistical factors of instantaneous values of welding current and welding arc voltage waveforms used for determining of welding process stability are presented. The results of coated electrodes welding properties are compared. The article presents the results of linear regression as well as the impact of the independent variables on the welding process performance. Finally the conclusions drawn from the research are given.

scholarly journals An E-Band 21-dB Variable-Gain Amplifier with 0.5-V Supply in 40-nm CMOS

Electronics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 804
Author(s):  
Gibeom Shin ◽  
Kyunghwan Kim ◽  
Kangseop Lee ◽  
Hyun-Hak Jeong ◽  
Ho-Jin Song
Keyword(s):  
Power Consumption ◽  
Frequency Band ◽  
Noise Figure ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Operating Frequency ◽  
Variable Gain Amplifier ◽  
Variable Gain ◽  
Operating Frequency Band ◽  
Shunt Capacitors

This paper presents a variable-gain amplifier (VGA) in the 68–78 GHz range. To reduce DC power consumption, the drain voltage was set to 0.5 V with competitive performance in the gain and the noise figure. High-Q shunt capacitors were employed at the gate terminal of the core transistors to move input matching points for easy matching with a compact transformer. The four stages amplifier fabricated in 40-nm bulk complementary metal oxide semiconductor (CMOS) showed a peak gain of 24.5 dB at 71.3 GHz and 3‑dB bandwidth of more than 10 GHz in 68–78 GHz range with approximately 4.8-mW power consumption per stage. Gate-bias control of the second stage in which feedback capacitances were neutralized with cross-coupled capacitors allowed us to vary the gain by around 21 dB in the operating frequency band. The noise figure was estimated to be better than 5.9 dB in the operating frequency band from the full electromagnetic (EM) simulation.

scholarly journals Ab initio perspective of ultra-scaled CMOS from 2D-material fundamentals to dynamically doped transistors

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Aryan Afzalian
Keyword(s):  
Field Effect ◽  
High Performance ◽  
Field Effect Transistor ◽  
High Mobility ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Grand Challenge ◽  
Gate Length ◽  
Delay Performance ◽  
Effect Transistor

AbstractUsing accurate dissipative DFT-NEGF atomistic-simulation techniques within the Wannier-Function formalism, we give a fresh look at the possibility of sub-10-nm scaling for high-performance complementary metal oxide semiconductor (CMOS) applications. We show that a combination of good electrostatic control together with high mobility is paramount to meet the stringent roadmap targets. Such requirements typically play against each other at sub-10-nm gate length for MOS transistors made of conventional semiconductor materials like Si, Ge, or III–V and dimensional scaling is expected to end ~12 nm gate-length (pitch of 40 nm). We demonstrate that using alternative 2D channel materials, such as the less-explored HfS2 or ZrS2, high-drive current down to ~6 nm is, however, achievable. We also propose a dynamically doped field-effect transistor concept, that scales better than its MOSFET counterpart. Used in combination with a high-mobility material such as HfS2, it allows for keeping the stringent high-performance CMOS on current and competitive energy-delay performance, when scaling down to virtually 0 nm gate length using a single-gate architecture and an ultra-compact design (pitch of 22 nm). The dynamically doped field-effect transistor further addresses the grand-challenge of doping in ultra-scaled devices and 2D materials in particular.

scholarly journals Complete Ring Artifacts Reduction Procedure for Lab-Based X-ray Nano CT Systems

Sensors ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 238
Author(s):  
Jakub Šalplachta ◽  
Tomáš Zikmund ◽  
Marek Zemek ◽  
Adam Břínek ◽  
Yoshihiro Takeda ◽  
...  
Keyword(s):  
High Efficiency ◽  
Image Inpainting ◽  
Simulated Data ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Detection Accuracy ◽  
Reduction Procedure ◽  
X Ray ◽  
Artifacts Reduction ◽  
Ct Data

In this article, we introduce a new ring artifacts reduction procedure that combines several ideas from existing methods into one complex and robust approach with a goal to overcome their individual weaknesses and limitations. The procedure differentiates two types of ring artifacts according to their cause and character in computed tomography (CT) data. Each type is then addressed separately in the sinogram domain. The novel iterative schemes based on relative total variations (RTV) were integrated to detect the artifacts. The correction process uses the image inpainting, and the intensity deviations smoothing method. The procedure was implemented in scope of lab-based X-ray nano CT with detection systems based on charge-coupled device (CCD) and scientific complementary metal–oxide–semiconductor (sCMOS) technologies. The procedure was then further tested and optimized on the simulated data and the real CT data of selected samples with different compositions. The performance of the procedure was quantitatively evaluated in terms of the artifacts’ detection accuracy, the comparison with existing methods, and the ability to preserve spatial resolution. The results show a high efficiency of ring removal and the preservation of the original sample’s structure.

Computational study of the staircase molecular conductivity of polyoxovanadates adsorbed on Au(111)

2021 ◽  
Vol 50 (16) ◽  
pp. 5540-5551
Author(s):  
Almudena Notario-Estévez ◽  
Xavier López ◽  
Coen de Graaf
Keyword(s):  
Metal Oxide ◽  
Computational Study ◽  
Complementary Metal Oxide Semiconductor ◽  
Cmos Technology ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Molecular Conduction ◽  
Conduction Properties ◽  
Molecular Conductivity

This computational study presents the molecular conduction properties of polyoxovanadates V6O19 (Lindqvist-type) and V18O42, as possible successors of the materials currently in use in complementary metal–oxide semiconductor (CMOS) technology.

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