Analysis for nonlinear error measurement method of pyranometer

In this paper, the instrument is designed by basing on principle of the measurement method of straightness error measurement of deep hole, the design technologies of A/D converters, automatic control and computer are used. The instrument can automatically acquire data, the process of acquire data is convenient, fast, safe and the data is reliable.

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A Ball-Bar Based Error Measurement Method for a RRTTT-Type Five-Axis Machine Tool

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.126-128.785 ◽

2010 ◽

Vol 126-128 ◽

pp. 785-790 ◽

Cited By ~ 1

Author(s):

Shih Ming Wang ◽

Han Jen Yu ◽

Da Fan Chen

Keyword(s):

Machine Tools ◽

Measurement Method ◽

Degrees Of Freedom ◽

High Efficiency ◽

Low Cost ◽

Measurement Methods ◽

Error Measurement ◽

Volumetric Errors ◽

Ball Bar ◽

Five Axis

Measurement method using telescoping ball-bar that can directly determine the volumetric errors of three main types of five-axis machine tools was developed. Adopting Single Socket method, and the method following the defined two-step measurements sequence and incorporating with derived error models, can quickly determine the five degrees-of-freedom (DOF) volumetric errors of five-axis machine tools. Comparing to most of the current used measurement methods, the proposed method provides the advantages of low cost, high efficiency, easy setup, and high accuracy.

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Development of an On-Machine Machining Error Measurement and Compensation System for Micro Milling Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.529 ◽

2010 ◽

Vol 447-448 ◽

pp. 529-533 ◽

Cited By ~ 2

Author(s):

Shih Ming Wang ◽

Han Jen Yu ◽

Jih Pong Yang ◽

Da Fan Chen

Keyword(s):

Measurement Method ◽

Model Comparison ◽

Detection Algorithm ◽

Milling Process ◽

Micro Milling ◽

Machining Accuracy ◽

Error Measurement ◽

Canny Edge ◽

Actual Shape ◽

Canny Edge Detection Algorithm

To further enhance the accuracy of a micro milling process, an effective error measurement method and error compensation method are necessary. An on-machine vision-based error measurement method integrating image re-constructive technology, camera pixel correction, and model comparison algorithm to provide the capability of non-contact measurement for micro-machined workpiece error was developed. With use of Canny Edge Detection algorithm and camera pixel calibration, the edge of the contour of a machined workpiece can be identified and used to re-construct the actual shape of the workpiece. The actual shape will then be compared to the theoretical shape of the workpiece. To prove the feasibility of the proposed methods and system, experiments were conducted. The results have shown the success of enhacing machining accuracy for a micro milling process.

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A Method for the Installation Measurement and Alignment of a Mirror Unit in the Solar Dish Concentrator

Applied Sciences ◽

10.3390/app10041511 ◽

2020 ◽

Vol 10 (4) ◽

pp. 1511

Author(s):

Jian Yan ◽

Youduo Peng ◽

Duzhong Nie

Keyword(s):

Hot Spots ◽

Measurement Method ◽

Alignment Error ◽

Error Measurement ◽

Feature Points ◽

Alignment Method ◽

Parabolic Dish ◽

Spatial Coordinates ◽

Parabolic Dish Concentrator ◽

Absorber Surface

The mirror unit installation error of the solar parabolic dish concentrator can adversely affect its optical performance causing optical intercept losses and hot spots on the absorber surface, which in turn affect safety. Thus, minimizing mirror installation error is considered very important. In this paper, a new method for the facet installation measurement and facet alignment of the mirror unit in the dish concentrator is presented. Firstly, a “clean” facet installation error measurement method using photogrammetry is presented. The photogrammetry measures the spatial coordinates of three feature points to reverse the mirror facet alignment error parameters. Next, two novel methods, a three-rotation alignment method and two-rotation alignment method for aligning the mirror facet are presented and corresponding mathematical models. The advantage of these alignment methods is that the adjustment value and order for each support bolt can be determined before the mirror facet is aligned, which could provide quantitative adjustment information to operator and avoid repeated adjustments. Finally, validity of the installation measurement and facet alignment method was verified by a numerical simulation and an experiment using a metal facet alignment. The presented methods do not rely on the geometry of the reflector mirror and could therefore have extensive uses in applications such solar tower and trough concentrator.

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Rapid Measurement Method for Small Work-Piece Flatness Error

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.373-375.790 ◽

2013 ◽

Vol 373-375 ◽

pp. 790-794 ◽

Cited By ~ 1

Author(s):

Rong Sheng Qiu ◽

Xiao Lin Wang ◽

Yong Ming Pan

Keyword(s):

Least Squares ◽

Measurement Method ◽

Work Piece ◽

Error Measurement ◽

Method Of Least Squares ◽

Rapid Measurement ◽

Displacement Sensors ◽

Key Points ◽

Flatness Error ◽

Small Work

A new flatness error measurement method was proposed for large quantities of E-type AC relay, which was consisted of three discontinuous plane. The research object of this thesis is on both sides of the work piece plane. The relay was measured by utilizing multiple laser displacement sensors, and used the development of PC software to extract the measurement key points and process the collected data, which was used the method of least squares to calculate more accurate flatness error value. This method can achieve substandard work-piece fast sorting and rapid online measure.

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A New Direct 9-line Geometric Error Measurement Method for CNC Machine Tools

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/790/1/012174 ◽

2020 ◽

Vol 790 ◽

pp. 012174

Author(s):

Huanlao Liu ◽

Muzammil Rasheed ◽

Miaojing Su ◽

Can Liu ◽

Xiaoli Li

Keyword(s):

Machine Tools ◽

Measurement Method ◽

Geometric Error ◽

Cnc Machine Tools ◽

Error Measurement ◽

Cnc Machine ◽

Geometric Error Measurement

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Research on the Cutting Force Induced Error Measurement Method of the CNC Machine Tools

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.426 ◽

2012 ◽

Vol 220-223 ◽

pp. 426-430

Author(s):

Huan Lao Liu ◽

Bao Yue Chen ◽

Feng Liu ◽

Guang Yu Tan

Keyword(s):

Cutting Force ◽

Machine Tools ◽

Measurement Method ◽

One Dimension ◽

Cnc Machine Tools ◽

Error Measurement ◽

Cnc Machine ◽

Working Process ◽

Machine Error ◽

Hard Cutting

The cutting force induced error has been more important as the hard cutting and hard cutting material used. This paper proposed the direct measurement method of cutting force induced error, which realized the corresponding directly of the cutting force and the value of error in the working process. According to the discrimination of machine error characteristics reflected by the different measuring methods, it puts forward to building the mixed error model based on the measuring technology of one dimension and two dimension. The results could provides the test data and theoretical basis for the mechanism of the processing performance affected by the dynamic behavior of machine tools.

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