Measurement of Spacecraft Simulator Motion Parameters Based on Multi-Vision System

A real-time measurement method based on multi-vision system is presented for measuring the motion parameters of three-DOF spacecraft simulator. Four cameras are arranged around the motion space of the simulator. When the simulator makes large range translation and rotation motion, 3D coordinate measurement can be realized for any marker provided that such marker is identified by 2 or more cameras. And the motion parameters of simulator can be measured when more than 3 markers are identified in each measurement. The experiment results verify this method and show it can achieve high measurement accuracy.

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A Cramer-Rao bound for the measurement accuracy of motion parameters and the accuracy of reconstruction of a surface profile observed by a binocular vision system

Pattern Recognition and Image Analysis ◽

10.1134/s1054661808030206 ◽

2008 ◽

Vol 18 (3) ◽

pp. 507-513

Author(s):

V. A. Grishin

Keyword(s):

Binocular Vision ◽

Measurement Accuracy ◽

Vision System ◽

Surface Profile ◽

Motion Parameters ◽

Cramer Rao Bound ◽

Binocular Vision System

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Research on Measure Method of Common Normal Length Variation of Bilateral Modification Gear

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.569.568 ◽

2012 ◽

Vol 569 ◽

pp. 568-571

Author(s):

Yu Lan Wei ◽

Qi Bo Yan ◽

Bing Li ◽

Hao Xu ◽

Ying Ying Fan

Keyword(s):

Measurement Accuracy ◽

Length Variation ◽

Human Intervention ◽

Normal Length ◽

Coordinate Measurement ◽

Coordinate Measurement Machine ◽

High Measurement ◽

Tooth Number ◽

The Common ◽

High Measurement Accuracy

In the conditions of rationally selecting of the measure tooth number, this paper puts forward a new method to calculate the common normal length variation, which is based on coordinate measurement machine to collect the data of bilateral modification gear's outline. Firstly, the addendum modification coefficient and tangential modification coefficient are used to determine the optimum measure tooth number, and then the common normal length variation is determined according to the definition. The experiment has shown that this way has a lot of advantages, such as the intensive data of sample points, less human intervention and high measurement accuracy.

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Binocular Vision-Based Measurement for Motion Parameters of Rocket Nozzle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.1056 ◽

2012 ◽

Vol 220-223 ◽

pp. 1056-1061 ◽

Cited By ~ 2

Author(s):

Yu Bo Guo ◽

Dong Ye ◽

Gang Chen ◽

Feng Yuan

Keyword(s):

Coordinate System ◽

Real Time ◽

Binocular Vision ◽

Time Measurement ◽

Rocket Nozzle ◽

Rotation Axes ◽

Real Time Measurement ◽

Dimension Measurement ◽

World Coordinate System ◽

Motion Parameters

This article presents a real-time measurement method for the motion parameters of rocket nozzle by means of binocular vision and rocket nozzle rotation axes. With preprocessing, this method defines the rotation transformation relation between world coordinate system and fixed nozzle coordinate system by measuring the position of two nozzle rotation axes in world coordinate system based on binocular vision. During real-time measurement, the nozzle motion parameters can be measured with transformation of marker coordinate from world coordinate system to fixed nozzle coordinate system. This method overcomes the disadvantages of existing method, such as larger measurement error of motion parameters, more markers and single-dimension measurement. The experiment results verified this method and show that it can achieve higher measurement accuracy.

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An Analysis Model for Structural Optimization of Polygon Ranging-Based Space Coordinate Measurement Network

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.239-240.760 ◽

2012 ◽

Vol 239-240 ◽

pp. 760-768

Author(s):

Jia Wen Hu ◽

Xiao Fen Yu ◽

Jun Tong Miu ◽

Ming Zhu

Keyword(s):

Structural Optimization ◽

Large Scale ◽

Measurement Accuracy ◽

Structural Parameters ◽

Base Stations ◽

Analysis Model ◽

Coordinate Measurement ◽

Local Accuracy ◽

High Measurement ◽

Space Coordinate

Polygon ranging-based space coordinate measurement network, which has high measurement accuracy and simple structure, is suitable for large-scale metrology. In practice, the measurement network should be constructed flexibly according to coverage and shape and measurement accuracy of different measurand. Based on this, a universal analysis model of structural optimization is proposed. The relation between structural parameters (amount and layout of measurement base stations) and distribution of measurement accuracy of the measurement network are researched on the model. The model can provide theoretic basis for optimized and flexible design of the measurement network. A case is used to illustrate this model. The results verify that the module can be used for scientifically establishing measurement system of ultra-large size, and also preliminarily simulating and optimally designing the being adopted measurement network and measurement method for meeting requirements of size and measurement accuracy (including global and local accuracy) of different work pieces.

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Real-time measurement and estimation of the 3D geometry and motion parameters for spatially unknown moving targets

Aerospace Science and Technology ◽

10.1016/j.ast.2019.105619 ◽

2020 ◽

Vol 97 ◽

pp. 105619 ◽

Cited By ~ 2

Author(s):

Jiawei Guo ◽

Yucheng He ◽

Xiaozhi Qi ◽

Guangxin Wu ◽

Ying Hu ◽

...

Keyword(s):

Real Time ◽

Time Measurement ◽

Moving Targets ◽

Real Time Measurement ◽

3D Geometry ◽

Motion Parameters

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Online Stereo Vision Coordinate Measurement System Using on Aircraft Assembly

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.381-382.207 ◽

2008 ◽

Vol 381-382 ◽

pp. 207-210

Author(s):

Zhi Jing Yu ◽

X.X. Li ◽

D.R. He ◽

Ji Gui Zhu ◽

X.Y. Si ◽

...

Keyword(s):

Stereo Vision ◽

Measurement Accuracy ◽

Vision System ◽

Online Measurement ◽

Feature Points ◽

Epipolar Constraint ◽

Coordinate Measurement ◽

Aircraft Assembly ◽

Measurement Results ◽

Fully Automatic

An optical imaging based fully automatic stereo vision system for aircraft assembly online measurement is presented and analyzed. In this system, the relative position of the two cameras can easily calibrated by imaging an optical reference bar in different locations and orientations throughout the measurement space according to epipolar constraint and the certified distance of the features on the reference bar. For measurement, the system takes infrared LEDs which attached at measured object as imaging targets, and makes use of the measurement results of these feature points space coordinates to calculate the related positions of the assembly aircraft parts. Furthermore, using automatic infrared LED light intensity and CCD cameras exposure time improve the calibration and measurement accuracy. The effectiveness of the proposed system has been test by experiments.

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