Data Normalization of Single Camera Visual Measurement Network System

2012 ◽  
Vol 263-266 ◽  
pp. 2381-2384
Author(s):  
Jing Zhou ◽  
Shi Jun Li ◽  
Dong Yan Huang ◽  
Xiao Lin Chen ◽  
Ye Chi Zhang
Keyword(s):  
Measurement System ◽  
Control Point ◽  
Network Control ◽  
Network System ◽  
Single Camera ◽  
Data Normalization ◽  
Feature Points ◽  
Visual Measurement ◽  
Optical Feature ◽  
Measuring Machine

With the development of visual measurement system , the visual measurement system of single camera which applied in the imaging theory of optical feature points , it has been widespread used in the modern production . Due to the limit of the environment in scene , the visual measurement system of single camera could not measure the shield between the measured objects each other . Focus on this problem , present a kind of the the knowledge of measurement network based on the visual measurement of single camera , set up the measurement network system via the multi-control points . Measure the optical feature points in every network control point via the visual measurement system of single camera; Normalize the measured coordinates into the same world coordinate system , then get the global data , and achieve the overall measurement ; Apply in the three coordinate measuring machine(CMM) to have the simulation experiment , the result indicates that the maximum absolute tolerance between the normalization coordinates via the center of point set and the ones measured by CMM directly is 0.058mm ; But the one between the coordinate repeatedly measured at the position of one network control point is 0.066mm ; So the data normalization has the advantage of more high precision .

Online Calibration of Visual Measurement System Based on Industrial Robot

ROBOT ◽  
2011 ◽  
Vol 33 (3) ◽  
pp. 299-302 ◽  
Author(s):  
Yi WANG ◽  
Changjie LIU ◽  
Xueyou YANG ◽  
Shenghua YE
Keyword(s):  
Measurement System ◽  
Industrial Robot ◽  
Visual Measurement ◽  
Online Calibration

The Predigest Project of Vehicle-Bone Multimedia Transmission and Control Network Based on FPGA

2012 ◽  
Vol 203 ◽  
pp. 62-66
Author(s):  
Hong Li ◽  
Qiao Zhen Hou
Keyword(s):  
Network Control ◽  
Control Network ◽  
Network System ◽  
Multimedia Transmission ◽  
Transmission Control ◽  
Hardware Platform ◽  
Arm Processor ◽  
Interface Module ◽  
Fpga Chip ◽  
And Control

The design uses 32 ARM processor S3C44B0X and Spartan™ -3E500 FPGA chip produced by Xinlinx company for setting up the hardware platform, and integrates the camera, GPS module, MiniGUI interface module. And realized bus vehicle mounted multimedia transmission control network control based on MOST. All of these are in the purpose of achieving a Predigest Project of vehicle-bone multimedia transmission and control network based on FPGA. The experiment indicated that, the transmission and control network system constructed by S3C44B0X and Spartan - 3E500 FPGA is low cast, simple and reliable.

scholarly journals Visual Measurement System for Wheel–Rail Lateral Position Evaluation

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1297
Author(s):  
Viktor Skrickij ◽  
Eldar Šabanovič ◽  
Dachuan Shi ◽  
Stefano Ricci ◽  
Luca Rizzetto ◽  
...  
Keyword(s):  
Measurement System ◽  
Inertial Sensor ◽  
Low Cost ◽  
Image Point ◽  
Low Velocity ◽  
Point Selection ◽  
Lateral Direction ◽  
Initial Field ◽  
Visual Measurement ◽  
Track Geometry

Railway infrastructure must meet safety requirements concerning its construction and operation. Track geometry monitoring is one of the most important activities in maintaining the steady technical conditions of rail infrastructure. Commonly, it is performed using complex measurement equipment installed on track-recording coaches. Existing low-cost inertial sensor-based measurement systems provide reliable measurements of track geometry in vertical directions. However, solutions are needed for track geometry parameter measurement in the lateral direction. In this research, the authors developed a visual measurement system for track gauge evaluation. It involves the detection of measurement points and the visual measurement of the distance between them. The accuracy of the visual measurement system was evaluated in the laboratory and showed promising results. The initial field test was performed in the Vilnius railway station yard, driving at low velocity on the straight track section. The results show that the image point selection method developed for selecting the wheel and rail points to measure distance is stable enough for TG measurement. Recommendations for the further improvement of the developed system are presented.

Position Estimation of Single Camera Visual System Based on Total Least Squares Algorithm

2012 ◽  
Vol 239-240 ◽  
pp. 1352-1355
Author(s):  
Jing Zhou ◽  
Yin Han Gao ◽  
Chang Yin Liu ◽  
Ji Zhi Li
Keyword(s):  
Visual System ◽  
Least Squares ◽  
Total Least Squares ◽  
Position Estimation ◽  
Feature Points ◽  
Perspective Theory ◽  
Optical Feature ◽  
The Matrix ◽  
Least Squares Algorithm ◽  
Set Up

The position estimation of optical feature points of visual system is the focus factor of the precision of system. For this problem , to present the Total Least Squares Algorithm . Firstly , set up the measurement coordinate system and 3D model between optical feature points, image points and the position of camera according to the position relation ; Second , build the matrix equations between optical feature points and image points ; Then apply in the total least squares to have an optimization calculation ; Finally apply in the coordinate measuring machining to have a simulation comparison experiment , the results indicate that the standard tolerance of attitude coordinate calculated by total least squares is 0.043mm, it validates the effectiveness; Compare with the traditional method based on three points perspective theory, measure the standard gauge of 500mm; the standard tolerance of traditional measurement system is 0.0641mm, the standard tolerance of Total Least Squares Algorithm is 0.0593mm; The experiment proves the Total Least Squares Algorithm is effective and has high precision.

scholarly journals Research on Temperature Compensation Method in Crankshaft Online Measurement System

2021 ◽  
Vol 11 (16) ◽  
pp. 7558
Author(s):  
Tingting Gu ◽  
Xiaoming Qian ◽  
Peihuang Lou
Keyword(s):  
Ambient Temperature ◽  
Measurement System ◽  
Temperature Compensation ◽  
Compensation Method ◽  
Displacement Sensor ◽  
Online Measurement ◽  
High Precision Measurement ◽  
Temperature Changes ◽  
Dragonfly Algorithm ◽  
Measuring Machine

The crankshaft online measurement system has realized the full inspection function with fast beats, at the same time it requires for high-precision measurement. Considering the effect of ambient temperature and temperature changes on measuring machine, the calibration part, the measured crankshaft and displacement sensor, a temperature compensation method is proposed. Firstly, relationship between calibration part and ambient temperature can be get through the zero calibration. Then use the material properties to obtain compensation values of the calibration part and the measured crankshaft part at different temperatures. Finally, the compensation parameters for displacement sensor can be obtained through the BP algorithm. The improved dragonfly algorithm (DA) is used to optimize the parameters of BP neural network algorithm. Experiments verify the effectiveness of IDA-BP for LVDT in temperature compensation. After temperature compensation, the error range of main journal radius is reduced from 0.0156 mm to 0.0028 mm, the residual error decreased from −0.0282 mm~+0.0018 mm to −0.0058 mm~−0.0008 mm. The influence of temperature changes on the measurement is reduced and measurement accuracy is improved through the temperature compensation method. The effectiveness of the method is proved.

A monocular visual measurement system for UAV probe-and-drogue autonomous aerial refueling

2018 ◽  
Vol 11 (2) ◽  
pp. 166-180 ◽  
Author(s):  
Long Xin ◽  
Delin Luo ◽  
Han Li
Keyword(s):  
Measurement System ◽  
Feature Matching ◽  
Perspective Transformation ◽  
High Accuracy ◽  
Noise Elimination ◽  
Aerial Refueling ◽  
Visual Measurement ◽  
Matching Algorithm ◽  
Content Type ◽  
Elimination Algorithm

PurposeThe purpose of this paper is to develop a monocular visual measurement system for autonomous aerial refueling (AAR) for unmanned aerial vehicle, which can process images from an infrared camera to estimate the pose of the drogue in the tanker with high accuracy and real-time performance.Design/methodology/approachMethods and techniques for marker detection, feature matching and pose estimation have been designed and implemented in the visual measurement system.FindingsThe simple blob detection (SBD) method is adopted, which outperforms the Laplacian of Gaussian method. And a novel noise-elimination algorithm is proposed for excluding the noise points. Besides, a novel feature matching algorithm based on perspective transformation is proposed. Comparative experimental results indicated the rapidity and effectiveness of the proposed methods.Practical implicationsThe visual measurement system developed in this paper can be applied to estimate the pose of the drogue with a fast speed and high accuracy and it is a feasible measurement strategy which will considerably increase the autonomy and reliability for AAR.Originality/valueThe SBD method is used to detect the features and a novel noise-elimination algorithm is proposed. Besides, a novel feature matching algorithm based on perspective transformation is proposed which is robust and accurate.

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