Performance study of non-contact surface measurement technology for use in an experimental fusion device

The ITER project is basically an engineering and construction project in order to build the ITER machine which is a scientific experimental fusion device. The seven members of the project have all created legal entities called Domestic Agencies to provide in-kind contributions to the ITER Organization (IO) for the supply of components which are manufactured by their suppliers. According to ITER agreement and due to nuclear safety involved in the fusion process, the project requires a license from the French Nuclear Safety Authority. One of nuclear safety regulations is the French Quality Order. The IO has established a Quality Assurance Program for the construction of the ITER machine to meet the requirements of the Order and to ensure that ITER activities are performed to achieve the safety and performance objectives of the ITER machine. The requirements in the program shall be followed by all performers involved in the project not only the IO, but DAs and their suppliers and subcontractors. This paper represents the quality requirements from the Order, and roles and responsibilities between each performer involved in the project. The paper also shows the main characteristics of the ITER Quality Assurance Program ensuring that all activities performed for the project conform to established and documented requirements.

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An innovative non-contact surface measurement solution for asphere, deep parabolic, and ogive radome geometries

10.1117/12.818569 ◽

2009 ◽

Author(s):

Scott DeFisher ◽

Mike Bechtold ◽

Dave Mohring ◽

Scott Bambrick

Keyword(s):

Contact Surface ◽

Surface Measurement

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3D Surface Measurement Technology of Micropart with Nano-tolerances

Journal of The Surface Finishing Society of Japan ◽

10.4139/sfj.56.780 ◽

2005 ◽

Vol 56 (12) ◽

pp. 780-780

Author(s):

Yasuhiro TAKAYA

Keyword(s):

Surface Measurement ◽

Measurement Technology ◽

3D Surface

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Precision surface measurement

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2011.0217 ◽

2012 ◽

Vol 370 (1973) ◽

pp. 4089-4114 ◽

Cited By ~ 21

Author(s):

X. Jiang

Keyword(s):

High Speed ◽

Functional Performance ◽

Surface Characteristics ◽

Subject Area ◽

Ease Of Use ◽

Surface Measurement ◽

Measurement Technology ◽

Manufacturing Environment ◽

Wide Range ◽

Ultra Precision

Surface size, geometry and texture are some of the most influential subjects in the fields of precision and ultra-precision engineering, defining the functional interface through which emerging products operate. Next-generation products demand super-smooth surfaces, freeform geometries or even deterministically introduced microstructures to provide functional performance. Technological progress using these surfaces types is possible only if the associated manufacturing processes are rigorously controlled and the surfaces are measurable. Metrology for advanced surfaces is not established. The current state of the art is challenged in respect to (i) surface characteristics, extremity of size, ultra precision, quality, geometric complexity, or combinations of these aspects, and (ii) measurement technology for the manufacturing environment, in particular, online, non-contact, high speed, ease of use, small footprint and robustness. This study addresses the challenges in this subject area and discusses some fundaments and principles derived from interdisciplinary research. The combination of these aspects is enabling the creation of manufacturing-environment-based measurement technology. This is expected to facilitate advanced surface manufacture over a wide range of sectors, including large science programmes and high-technology engineering.

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Multiposition Rotation Interference Absolute Measurement Method for High-Precision Optical Component Surfaces

International Journal of Optics ◽

10.1155/2021/6621939 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Xueliang Zhu ◽

Fengming Nie ◽

Bingcai Liu ◽

Ruikun Liu ◽

Ailing Tian

Keyword(s):

High Precision ◽

Measurement Method ◽

Absolute Measurement ◽

Optical Component ◽

Computational Method ◽

Surface Measurement ◽

Measurement Technology ◽

Reference Mirror ◽

Large Aperture ◽

Absolute Measurements

Modern optical engineering requires increasingly sophisticated interferometry methods capable of conducting subnanometer scale measurements of the large aperture, high-precision optical component surfaces. However, the accuracy of interferometry measurement is limited to the accuracy with which the surface of the reference mirror employed in the interferometer system is known, and the influence of gravity-induced deformation cannot be ignored. This is addressed in the present work by proposing a three-flat testing method based on multiposition rotation interference absolute surface measurement technology that combines the basic theory of N-position rotation with the separability of surface wavefront functions into sums of even and odd functions. These functions provide the rotational symmetric components of the wavefront, which then enables the absolute surface to be reconstructed based on the N-position rotation measurements. In addition, we propose a mechanical clamping combined with computational method to compensate for the gravity-induced deformations of the flats in the multiposition rotation absolute measurements. The high precision of the proposed absolute surface measurement method is demonstrated via simulations. The results of laboratory experiments indicate that the combination compensation method provides the high-precision surface reconstruction outcomes. The present work provides an important contribution for supporting the interferometry measurement of large aperture, high-precision optical component surfaces.

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