scholarly journals Time-Division-Based Multiple-Viewpoint 3-D Measurement System for Real-Time, High-Speed, and High-Accuracy Model Movie Acquisition

2008 ◽  
Vol 62 (3) ◽  
pp. 392-397 ◽  
Author(s):  
Yusuke Yachide ◽  
Makoto Ikeda ◽  
Kunihiro Asada
Keyword(s):  
Real Time ◽  
Measurement System ◽  
High Speed ◽  
High Accuracy ◽  
Time Division

Temperature Measurement System for Low Pressure Ratio Turbine Testing

2003 ◽  
Author(s):  
R. Va´zquez ◽  
J. M. Sa´nchez
Keyword(s):  
Temperature Measurement ◽  
Measurement System ◽  
High Speed ◽  
New Technologies ◽  
Pressure Ratio ◽  
Low Pressure ◽  
High Accuracy ◽  
Single Stage ◽  
Measurement Systems ◽  
Temperature Measurement System

In 1999, ITP (Industria de Turbopropulsores, S.A.) launched a wide on-going research program focusing on new technologies to provide significant improvements in Low Pressure Turbines cost and weight. As consequence of the new technologies the experience limits are exceeded and new unknown concepts, like high stage loading turbines, must be explored and then a wide experimental work is required for validation purposes. Cold flow single stage rigs in high-speed facilities were selected by ITP as main vehicle to carry out the experimental validation. Single stage Low Pressure Turbine rigs have low-pressure ratio and power consumption, therefore efficiency predictions based on temperature drop require high accuracy thermocouple measurement systems (precision uncertainties lower than ±50 mK), if small efficiency variations must be captured. In this paper, a detailed uncertainty analysis is introduced and a temperature measurement system that allows achieving such high measurement accuracy is evaluated and described. Type T thermocouples are proposed for use in the range 0°C to 80°C, which are individually calibrated. The procedure followed for this calibration is presented and how is possible to achieve a precision of 30 mK. It is also shown as conventional UTR based on metal plates can behave as good as thermal baths in terms of temperature uniformity and errors, with the adequate isolation and temperature reference calibration. The conventional data recording and voltage measurement systems are experimentally evaluated, and they are found as main source of temperature errors. Although following some recommendations the precision of those systems can be improved, it is experimentally probed and therefore suggested the use of high accuracy voltmeter with a commutation unit to reduce significantly the temperature uncertainty. Finally a miniature Kiel Shroud is proposed and aerodynamically characterised in a high-speed facility. Mach, Reynolds number, yaw, blockage and manufacturing tolerance impact on recovery factor can be inferred from those results.

Design and Implementation of Real-Time Polarization Measurement System Based on LabVIEW

2013 ◽  
Vol 411-414 ◽  
pp. 1501-1504
Author(s):  
Ye Yu ◽  
Yan Gan Zhang ◽  
Xue Guang Yuan
Keyword(s):  
Real Time ◽  
Measurement System ◽  
High Speed ◽  
Polarization Measurement ◽  
Experimental Result ◽  
Photoelectric Conversion ◽  
Graphical Programming ◽  
Data Acquisition Card ◽  
Calibration Matrix ◽  
High Computational Efficiency

A rapid real-time polarization measurement system was designed and implemented in this paper. The system is centered round a laptop running application developed for the purpose. The paper illustrates how to build such an excellent application with National Instruments graphical programming language LabVIEW, a synchronized high speed multi-channels data acquisition card and some photoelectric conversion module in detail. With simple and friendly user interface, the experimental result shows that the measurement system has high computational efficiency, high precision calibration matrix, which can be efficiently utilized in experiments relating to the measurement of polarization.

Study on Doppler Velocity Measurement System

2012 ◽  
Vol 562-564 ◽  
pp. 1240-1243
Author(s):  
Jian Chao Li ◽  
Jun Hong Su ◽  
Ming Gao
Keyword(s):  
Measurement System ◽  
Velocity Measurement ◽  
High Speed ◽  
Processing System ◽  
Measurement Range ◽  
High Accuracy ◽  
Laser Doppler ◽  
Doppler Velocity ◽  
Dual Frequency ◽  
Frequency Laser

In order to satisfy the high accuracy velocity measurement requirement, using the improved dual-frequency laser Doppler velocity measurement principle, designed a set of laser Doppler velocity measurement system. System consists of two parts: optical system and signal acquisition and processing system. Through the establishment of dual-frequency laser Doppler velocity measurement experimental platform for testing, the result shows that the method can be carried on the high accuracy velocity measurement which in high speed move object. Measurement range from 0.1 m/s to 50 m/s, the error is less than 2 percent and it could increase the speed measurement range.

scholarly journals The real-time visual measurement system of rail creeping of high-speed railway

2020 ◽  
Vol 53 (3-4) ◽  
pp. 757-763
Author(s):  
Jingbo Xu ◽  
Xiaomeng Cui ◽  
Wenbo Ma
Keyword(s):  
Real Time ◽  
Measurement System ◽  
High Speed ◽  
Target Location ◽  
Region Of Interest ◽  
Field Application ◽  
Stable Operation ◽  
High Speed Railway ◽  
Visual Measurement ◽  
Remote Transmission

Changes in temperature and stress will lead to the rail creeping of high-speed railway, which becomes a hidden danger in the operation of trains. This paper studies a real-time visual measurement system for creeping displacement monitoring. The bilateral line extraction to determine the target location overcomes the influence of ambient light on image grayscale. The dynamic region of interest setting method is produced to lock and track the target. The self-calibration technology makes the system suitable for field application. The remote transmission of monitoring data is realized through narrow band internet of things (NB-IOT). These methods solve the problems in practical application. The monitoring system provides a reliable guarantee for the safe and stable operation of high-speed railway.

Error Analysis of the ATOS 3D Optical Scanner in Vehicle Measurement

2013 ◽  
Vol 365-366 ◽  
pp. 654-657
Author(s):  
Xue Dong Xie ◽  
Wei Ling Zhao
Keyword(s):  
Measurement System ◽  
Reference Point ◽  
High Speed ◽  
Three Dimensional ◽  
High Accuracy ◽  
Actual Measurement ◽  
Optical Scanning ◽  
Optical Scanner ◽  
Actual Use ◽  
Multiple Scan

ATOS three-dimensional optical scanner is one of the most advanced technologically three-dimensional optical scanning devices. It can automatically put together the multiple scan view image by the reference point of the measurement system, with high accuracy, high speed Etc. It is widely used in automobiles. The paper combines with the experience in vehicle measurements, analysis the error cause in the actual use, points out ways to reduce or eliminate error. It has the great application value to actual measurement.

scholarly journals Development of a Real-Time Human-Robot Collaborative System Based on 1 kHz Visual Feedback Control and Its Application to a Peg-in-Hole Task

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 663
Author(s):  
Yuji Yamakawa ◽  
Yutaro Matsui ◽  
Masatoshi Ishikawa
Keyword(s):  
Real Time ◽  
High Speed ◽  
High Accuracy ◽  
Robot Hand ◽  
Collaborative System ◽  
Visual Sensing ◽  
Hand Control ◽  
The Stability ◽  
Visual Feedback Control ◽  
Human Robot Collaboration

In this research, we focused on Human-Robot collaboration. There were two goals: (1) to develop and evaluate a real-time Human-Robot collaborative system, and (2) to achieve concrete tasks such as collaborative peg-in-hole using the developed system. We proposed an algorithm for visual sensing and robot hand control to perform collaborative motion, and we analyzed the stability of the collaborative system and a so-called collaborative error caused by image processing and latency. We achieved collaborative motion using this developed system and evaluated the collaborative error on the basis of the analysis results. Moreover, we aimed to realize a collaborative peg-in-hole task that required a system with high speed and high accuracy. To achieve this goal, we analyzed the conditions required for performing the collaborative peg-in-hole task from the viewpoints of geometric, force and posture conditions. Finally, in this work, we show the experimental results and data of the collaborative peg-in-hole task, and we examine the effectiveness of our collaborative system.

scholarly journals A super-grayscale and real-time computer-generated Moiré profilometry using video grating projection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hongmei Li ◽  
Yiping Cao ◽  
Yingying Wan ◽  
Chengmeng Li ◽  
Cai Xu ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Real Time ◽  
Ccd Camera ◽  
High Accuracy ◽  
Time Measurement ◽  
Charge Coupled Device ◽  
Real Time Measurement ◽  
Refresh Cycle ◽  
Fringe Patterns ◽  
Time Division

AbstractBy using the time-division multiplexing characteristics of the projector and the integral exposure characteristics of the charge coupled device (CCD) camera, a super-grayscale and real-time computer-generated Moiré profilometry based on video grating projection is proposed. The traditional digital static grating is of 256-grayscale at most. If an expected super-grayscale grating with a maximum grayscale of 766 is designed and divided into three 256-grayscale fringe patterns with balanced grayscale as far as possible, they can be synthesized into a repeated playing video grating instead of the traditional static grating. When the video grating is projected onto the measured object, as long as the exposure time is set to three times the refresh cycle of the video grating, the super-grayscale deformed patterns in the 766-grayscale can be captured with a 10-bit CCD camera, so that the deformed patterns are realistic. The digital error in computer-generated Moiré profilometry is effectively reduced. In addition, this method can expand the linear range of the deformed pattern by 20% in computer Moiré profilometry. Therefore, the proposed method has the perspectives of high accuracy and real-time measurement. Theoretical analysis and experimental results demonstrate the validity and capability of the proposed method.

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