M. Valenzuela, J. A. Yagüe, J. A. Albajez, J. J. Aguilar
In this paper a calibration technique for the error mapping of a 2D sensor - a cross-grid encoder – is presented. A reversal technique to assess the squareness errors is used. The calibration set up includes a metrology frame made of Zerodur®, a very low coefficient thermal expansion material in order to reduce thermal errors. Additionally, an analysis by means of finite element method is carried out for an adequate design of the set up. Finally, the uncertainty values for the 2D cross-grid encoder system are calculated.
XX IMEKO World Congress
· TC14
· 2012
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J. Santolaria, A. Brau , D. Samper, J. Mainz, J. J. Aguilar
In this work we present a novel kinematic parameter identification procedure of an articulated arm coordinate measuring machine (AACMM). This procedure is based on a geometric multilateration system constructed from four Laser Trackers (LT’s) that allow us to determine the spatial localization of a retroreflector target. Then, from the captured nominal data obtained by the LT’s (used as a gauge instrument) and the data obtained by the AACMM, an objective function based on Euclidean distances and standard deviations is proposed. Hence, the self-calibration algorithm of the LT’s positions and...
XX IMEKO World Congress
· TC14
· 2012
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J. J. Aguilar, S. Aguado, J. Santolaria, D. Samper
This paper presents the role played by multilateration when laser trackers (LTs) are used in volumetric verification of long range machine tools. A comprehensive study on the influence of LTs positioning has been done. The parameters taken into account during the positioning of the LTs are: the viewing angle, the distance to the work space and the LT measurement errors. Also, different self-calibration techniques for calculating the LTs positioning are explained in order to show their influence in the correction improvement using multilateration techniques. Finally, it is shown how obtained...
XX IMEKO World Congress
· TC14
· 2012
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H. Matsumoto, X. Wang, K. Takamasu
A heterodyne interference system is developed for base-lines measurement by using an acoustic optical modulator and a stabilized optical-frequency comb. The temporal coherence interference with the optical-frequency comb happen at discrete positions, where a pair of pulse trains overlaps with each other. An optical delay of the interferometer with a piezo-electric transducer is realized to find the peak position of interference fringe pattern and the absolute distance is obtained with a high accuracy. The interferometer is applied to a distance of base-lines up to 403 m and the experimental...
XX IMEKO World Congress
· TC14
· 2012
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C. Narin, S. Takahashi, K. Takamasu, H. Matsumoto
A high-frequency part of repetition frequency modes of mode-locked fiber laser is selected by a tandem Fabry–Pérot etalon. The 3-GHz repetition-modified laser is transmitted to a Michelson interferometer. The interference fringes generated have a temporal coherence pattern and can make positioning in space. The optical system of the interferometer is designed as double-path beams. A center between two beams is located at the position of a measuring probe of CMM. Using this design, we can apply the modelocked fiber laser to artifacts following contact method. The advantage of the contact...
XX IMEKO World Congress
· TC14
· 2012
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Kazuki Fujiyama, Miyu Ozaki, Ryoshu Furutani
Most of positioning devices are calibrated by comparing with an artifact or other measuring machine. These methods need an artifact or a measuring machine. On the other hand a Self-calibration is the best method for small or big positioning devices which are hard to make artifacts, because the method does not need an artifact. In the purpose of this study is to apply the Self-calibration to a parallel mechanism. In this paper, we built a small 3DOF (x and y direction and rotational movement around stylus) parallel mechanism and studied its movement. It was proved the method had the benefit...
XX IMEKO World Congress
· TC14
· 2012
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Tsutomu Itabashi, Miyu Ozaki, Ryosyu Furutani
Coordinate Measuring Machine (CMM) is often used for geometrical measurement due to its precision and general versatility. Recently the case that the CMM is placed in production line environment, is increasing. There are a lot of factors which make precision of measurement worse, like dust, thermal fluctuation, a physical collision and so on. To check these influences to precision of measurement, daily inspection of CMM is necessary. In previous research, the method of daily inspection of CMM was proposed. The result of inspection by two artifacts with different ball layout is shown.
XX IMEKO World Congress
· TC14
· 2012
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Adam Wozniak
The accuracy of touch probes of coordinate measuring machines (CMM) will be analyzed, taking into consideration identification of respective sources of errors.
XX IMEKO World Congress
· TC14
· 2012
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Dong Wei, Kiyoshi Takamasu, Hirokazu Matsumoto
As an alternative to the conventional method, which length measurement is performed as a function of the wavelength of a monochromatic laser source, we proposed the method of measuring arbitrary and absolute length using the pulse repetition interval of a femtosecond optical frequency comb (FOFC - the national standard tool for measuring length in Japan). A helium-neon laser evaluation system was developed for distance determination comparison experiment and its uncertainty estimation was performed in order to validate the proposed method.
XX IMEKO World Congress
· TC14
· 2012
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C. R. Baldo, D. M. Yamanaka, D. C. B. Silva
The miniaturization of parts and components and the growing demand for more accurate measurements have led to ongoing development in the field of dimensional metrology. The development of new sensors mounted on coordinate measuring machines, has enabled metrologists to handle dimensional engineering challenges. Probing systems that combine mechanical and optical principles and provide three-dimensional information about micro-scale features in micro- and meso-scale components are outlined in this paper. Real application cases are reported and their practical issues discussed under a...
XX IMEKO World Congress
· TC14
· 2012
· Download