Paper | Title | Other Keywords | Page |
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WEOAMA03 | High-Accuracy Small Roll Angle Measurement Method Based on Dual-Grating Diffraction Heterodyne Interferometer | laser, GUI, experiment, radiation | 163 |
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Funding: The work is supported by National Natural Science Foundation of China, NSFC (Grant No. 61505213). Small roll angle (ROLL) is an crucial parameter for the motion performances of ultra-precision guide way often applied in fine mechanics and instruments of synchrotron radiation, such as long trace profiler (LTP). However, it is difficult to be measured by conventional methods including interferometer and autocollimator owing to their low sensitivities in axial direction. There is an orthogonal dilemma between measured direction and angular displacement plane for ROLL measurement. Therefore, a novel method based on dual-grating diffraction heterodyne interferometer is presented, which uses the combining scheme of diffraction grating and heterodyne interferometer to overcome the orthogonal problem. Moreover, the design of differential structure with dual-grating and grating interferometer instead of pure interferometer, is adopted to improve the practicability against the environment, e. g. air fluctuation, inconstant rotation center. It has inherited advantages of high-resolution up to 2nrad, high sampling rate up to 50kHz, and contactless by mathematical modeling and analysis. So, theoretcial and experimental verifications are both implemented to its validation. |
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Slides WEOAMA03 [2.304 MB] | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-WEOAMA03 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPH18 | Operation Status of HLS System Installed to Measure Ground Change of Large Scientific Equipment in Real Time | FEL, alignment, linac, survey | 245 |
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Several parts that comprise the large scientific equipment should be installed and operated at precise three-dimensional location coordinates X, Y, and Z through survey and alignment to ensure their optimal performance. As time goes by, however, the ground goes through uplift and subsidence, which consequently changes the coordinates of installed components and leads to alignment errors. As a result, the system parameters change, and the performance of the large scientific equipment deteriorates accordingly. Measuring the change in locations of systems comprising the large scientific equipment in real time would make it possible to predict alignment errors, locate any region with greater changes, realign components in the region fast, and shorten the time of survey and alignment. For this purpose, a WPS's (wire position sensor) are installed in undulator section and a HLS's (hydrostatic leveling sensor) are installed in PAL-XFEL building. This paper is designed to introduce performance enhancements to reduce observed phenomena and measurement errors in the HLS system operation process. | |||
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Poster WEPH18 [2.958 MB] | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-WEPH18 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||