检索结果-南通市图书馆

Comparison of GUF and Monte Carlo methods to evaluate task-specific uncertainty in laser tracker measurement

Journal of Central South University 2014年第10期21卷 3793-3804页

作者：杨景照李国喜吴宝中龚京忠王杰 College of Mechatronics and Automation National University of Defense Technology

Measurement uncertainty plays an important role in laser tracking measurement analyses. In the present work, the guides to the expression of uncertainty in measurement(GUM) uncertainty framework(GUF) and its supplement, the Monte Carlo method, were used to estimate the uncertainty of task-specific laser tracker measurements. First, the sources of error in laser tracker measurement were analyzed in detail, including instruments, measuring network fusion, measurement strategies, measurement process factors(such as the operator), measurement environment, and task-specific data processing. Second, the GUM and Monte Carlo methods and their application to laser tracker measurement were presented. Finally, a case study involving the uncertainty estimation of a cylindricity measurement process using the GUF and Monte Carlo methods was illustrated. The expanded uncertainty results(at 95% confidence levels) obtained with the Monte Carlo method are 0.069 mm(least-squares criterion) and 0.062 mm(minimum zone criterion), respectively, while with the GUM uncertainty framework, none but the result of least-squares criterion can be got, which is 0.071 mm. Thus, the GUM uncertainty framework slightly underestimates the overall uncertainty by 10%. The results demonstrate that the two methods have different characteristics in task-specific uncertainty evaluations of laser tracker measurements. The results indicate that the Monte Carlo method is a practical tool for applying the principle of propagation of distributions and does not depend on the assumptions and limitations required by the law of propagation of uncertainties(GUF). These features of the Monte Carlo method reduce the risk of an unreliable measurement of uncertainty estimation, particularly in cases of complicated measurement models, without the need to evaluate partial derivatives. In addition, the impact of sampling strategy and evaluation method on the uncertainty of the measurement results can also be taken into accou

关键词： task-specific uncertainty laser tracker measurement uncertainty evaluation Monte Carlo method uncertainy framework(GUF)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Algorithm for Detecting Volumetric Geometric Accuracy of NC Machine Tool by laser tracker

引用

Chinese Journal of Mechanical Engineering 2013年第1期26卷 166-175页

作者： WANG Jindong GUO Junjie State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Quick and accurate detecting the error of NC machine tool and performing the error compensation are important to improve the machining accuracy of NC machine tool. Currently, there are many methods for detecting the geometric accuracy of NC machine tool. However, these methods have deficiencies in detection efficiency and accuracy as well as in versatility. In the paper, a method with laser tracker based on the multi-station and time-sharing measurement principle is proposed, and this method can rapidly and accurately detect the geometric accuracy of NC machine tool. The machine tool is controlled to move in the preset path in a 3D space or 2D plane, and a laser tracker is used to measure the same motion trajectory of the machine tool successively at different base stations. The original algorithm for multi-station and time-sharing measurement is improved. The space coordinates of the measuring point obtained by the laser tracker are taken as parameter values, and the initial position of each base point can be determined. The redundant equation concerning the base point calibration can be established by the distance information of the laser tracker, and the position of each base point is further determined by solving the equation with least squares method, then the space coordinates of each measuring point can be calibrated. The singular matrix does not occur in calculation with the improved algorithm, which overcomes the limitations of the original algorithm, that the motion trajectory of machine tool is in a 3D space and there exits height difference between the base stations. Adopting the improved algorithm can expand the application of multi-station and time-sharing measurement, and can meet the quick and accurate detecting requirements for different types of NC machine tool.

关键词： laser tracker NC machine tool geometric accuracy redundant equation singular matrix least square method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research on volumetric error compensation for NC machine tool based on laser tracker measurement

引用

Science China(Technological Sciences) 2012年第11期55卷 3000-3009页

作者： WANG JinDong GUO JunJie State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710049China

Error compensation is an effective method to improve the accuracy of NC machine *** compensation results are greatly affected by the error modeling and error measurement,so how to establish an accurate error model and accurately detect the geometric errors of machine tool are particularly *** the paper,the volumetric error model of a multi-axis NC machine tool is established based on the multi-body system *** relative position deviations between the rotary axis and linear axis of the machine tool are considered in the *** achieve quick and accurate detection,a laser tracker is based on the multi-station and time-sharing measurement principle to detect the geometric errors of machine tool,and each error of linear axis and rotary axis can be identified by this *** the error model,error compensation can be carried out by modifying the machining process(G code),and the machining accuracy can be improved with the new G *** results show that the motion errors of a milling machine are significantly reduced after compensation,which verifies the effectiveness of compensation method.

关键词： error modeling multi-body system theory laser tracker error compensation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Kinematic Calibration of Asymmetricly Actuated 6-DOF 3-PPPS Parallel Mechanism

引用

Transactions of Nanjing University of Aeronautics and Astronautics 2016年第3期33卷 294-300页

作者： Chen Lei Huang Xiang Ma Zhiqiang Li Shuanggao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Institute of Aeronautical Manufacturing Technology Research Shanghai Aircraft Manufacturing Co.Ltd

An asymmetric actuated 3-PPPS parallel mechanism was analyzed in its application to an aircraft wing adjustment *** posture alignment precision at the wing ends was enhanced with a kinematic calibration method.A constraint equation was built based on a constraint condition that distances among spherical joints of the mechanism were constant,and further eight groups of analytic forward solutions of all poses of the mechanism were *** inverse equation of the posture alignment displacements of aircraft wing parts was built based on space vector chains,and a mapping equation of the pose and geometric errors of the posture alignment mechanism containing 39 error sources was derived by differentiating the kinematic equation of the *** kinematic calibration experiments,the maximum position error of the posture alignment platform dropped from 2.67 mm to 0.82 mm,the maximum angle error decreased from 0.481° to 0.167°,and the posture alignment precision of the aircraft wing end was improved.

关键词： aircraft wing adjustment parallel mechanism forward numerical solution laser tracker kinematic calibration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research on error accumulation control of three-dimensional adjustment with offset constraint

引用

Radiation Detection Technology and Methods 2022年第4期6卷 569-576页

作者： Wang Xiaolong Kang Ling Dong Lan Li Bo Men Lingling Luo Tao Wang Tong Liang Jing He Zhenqiang Ke Zhiyong Ma Na Lu Shang Han Yuanying Yan Luping Zhang Luyan Liu Xiaoyang Yan Haoyue Li Chunhua Wu Lei Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China

Background Currently,laser tracker is the primary instrument used to carry out three-dimensional position measurement in accelerator ***,three-dimensional measuring data processed by three-dimensional adjustment are more rigorous,however,error accumulation is found in *** In order to control error accumulation and further improve the measurement accuracy of accelerator alignment,this research introduces the laser alignment system into the activity of measurement and data *** A measurement scheme combining laser tracker and laser alignment system is *** construct the constraint condition,the offset values from the measuring points to the laser straight-line datum were *** carry out the three-dimensional adjustment with offset constraint,the laser tracker observations were *** A three-dimensional adjustment function model of laser tracker observations is *** construction method of the constraint equation is researched,and the calculation formulas of the three-dimensional adjustment with offset constraint are derived.A 200 m linac tunnel control network is designed,using simulation measurement method,the measuring data of laser tracker and the offset values from the measuring points to the laser straight-line datum were *** simulated data are calculated by the method given in this paper and the result is *** Simulation result shows introducing the laser alignment system into laser tracker measurement and applying the three-dimensional adjustment with offset constraint can effectively suppress the error accumulation caused by long distance move station measurement.

关键词： Accelerator alignment Error accumulation laser alignment system laser tracker Three-dimensional adjustment Offset constraints Simulation measurement

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Alignment technology of heavy ion medicalmachine

引用

Radiation Detection Technology and Methods 2019年第2期3卷 37-43页

作者： Wenjun Chen Yaqing Yang Guozhu Cai Zhiguo Cui Xiaorong Zhu Shaoming Wang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Huizhou Research Center of Ion Science Huizhou 516000China

Background Heavy ion medical machine(HIMM)is built by the Institute of Modern Physics,Chinese Academy of Sciences,with a high-energy beam transport line with a height of 18 m,and its complex space mounting structure increases the difficulty of installation and *** The aim of this paper is to provide methods to install all accelerator components efficiently and to ensure that the alignment accuracies of all installed components are within the designed *** We accomplished the fiducialization and pre-alignment of complex modules by combining the laser tracker and the alignment *** analyzing various elements that affect the accuracy of alignment,a method of alignment for high-energy beam transport line was proposed based on high-precision three-dimensional control *** All components have been installed and aligned in a short time,alignment position accuracy of magnets is less than 0.1 mm,and the treatment components alignment accuracy is no more than 0.4 *** On the basis of error analysis,all alignment results are better than the required precisions,and all of these guaranteed the successful operation of HIMM.

关键词： Heavy ion accelerator Three-dimensional control network laser tracker Alignment Fiducialization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Determination of the Refraction Coefficient and Its Uncertainty by Using Modern Hydrostatic Levelling Systems

引用

Journal of Civil Engineering and Architecture 2021年第7期15卷 382-392页

作者： Konstantinos Nikolitsas CERN 1211 Geneva 23Switzerland

In spite of the technological development of the last decades in the field of the geodetic instruments,some parameters,which affect their performance,are difficult to be *** of these parameters is the geodetic *** refraction describes the alteration in the direction of the light curve as it propagates through the different layers of the lower part of the Earth’s *** purpose of this research work is to investigate the uncertainty of the refraction coefficient of a new proposed *** methodology is based on:(a)the exploitation of the full trigonometric height equation,(b)the ability of the Hydrostatic Levelling System(HLS)to provide height differences with±10μm *** experimental application has been set up in a section of the underground tunnel complex at the European Organization for Nuclear *** this indoor application,the determination of the refraction coefficient at a laser tracker station using the precise height differences provided by an HLS has been *** addition,this methodology has been tested by comparing its results with those that have been obtained from the Temperature Gradient(TG)method for the determination of the refraction *** results are very encouraging for the efficiency of the *** the same time,some limitations on the implementation of the proposed methodology have been highlighted.

关键词： HLS laser tracker refraction coefficient TG

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Estimation of Three-Dimensional Volumetric Errors of Numerically Controlled Machine Tools by a Tracking Interferometer

引用

Journal of Mechanics Engineering and Automation 2011年第4期1卷 313-319页

作者： Soichi Ibaraki Kunitaka Takeuchi Tomoaki Yano Toshiyuki Takatsuji Sonko Osawa Osamu Sato Department of Micro Engineering Graduate School of Engineering Kyoto University Yoshida-honmachi Sakyo-ku Kyoto606-8501 Japan Fine Manufacturing Systems Group Advanced Manufacturing Research Institute National Institute of Advanced IndustrialScience and Technology Japan National Metrology Institute of Japan National Institute of Advanced Industrial Science and Technology Japan

This paper presents the estimation of three-dimensional volumetric errors of a machining center by using a tracking interferometer. A tracking interferometer is a laser interferometer with the mechanism to steer the laser direction to follow a target retroreflector. Based on the triangulation principle, the three-dimensional position of the target can be estimated from measured laser displacements. Its capability to measure three-dimensional positioning errors for arbitrary trajectories is important for the indirect measurement of the machine＇s kinematic model. This paper presents experimental investigation of the estimation accuracy of the multilateration-based measurement by a tracking interferometer. A tracking interferometer developed by a part of the authors is used in experiments. In the present experiment, the measured volume of target positions was 100 mm × 100 mm × 100 mm. The estimation accuracy of targets within this volume was not sufficiently high compared to the positioning error of the measured machine tool. The results of the experiment and simulation show that the estimation uncertainty is dependent on tracking interferometer locations relative to target locations. Error sensitivity analysis shows that wider distribution of tracker positions in XY improves the estimation accuracy.

关键词： Tracking interferometer laser tracker volumetric errors multilateration machine tools estimation accuracy.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：