Shape and surface measurement technology by an improved shape-from-shading neural algorithm

2000 ◽  
Vol 47 (1) ◽  
pp. 225-230 ◽  
Author(s):  
Sin-Yeung Cho ◽  
T.W.S. Chow
Keyword(s):  
Shape From Shading ◽  
Surface Measurement ◽  
Measurement Technology

scholarly journals Precision surface measurement

2012 ◽  
Vol 370 (1973) ◽  
pp. 4089-4114 ◽  
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.

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

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.

Prospect of the Next-Term Human Body Measurement in Japan

2000 ◽  
Vol 44 (38) ◽  
pp. 748-750
Author(s):  
Kazushige Suzuki
Keyword(s):  
Human Body ◽  
Body Shape ◽  
Measurement Data ◽  
Surface Measurement ◽  
Measurement Technology ◽  
Anatomical Landmarks ◽  
Body Parts ◽  
Body Measurement ◽  
Human Engineering ◽  
Quality Life

Research Institute of Human Engineering for Quality Life (HQL) is planning to update the current human body measurement database by collecting new body measurement data, as well as it carries out the following development of measurement technology from 1999 to 2001. I. Development of New 3-D Body Surface Measurement System (1999 ∼ 2001) a. Generation of the super accurate data and reduction of the measuring time b. Measurement of the invisible human body parts c. Extraction of anatomical landmarks II. Development of New Data Format for 3-D Human Body Shape (1999) The human body shape generated from image data has difficulty in comparing data and comprehending distribution. This project aims at conducting the research and development to make the scan result easier to analyze and utilize.

scholarly journals Application of 3D laser scanning technology in engineering field

2021 ◽  
Vol 233 ◽  
pp. 04014
Author(s):  
Chang’an Hu ◽  
Linghui Kong ◽  
Fei Lv
Keyword(s):  
Laser Scanning ◽  
New Technology ◽  
Single Point ◽  
3D Models ◽  
The Body ◽  
Surface Measurement ◽  
Measurement Technology ◽  
3D Laser Scanning ◽  
High Definition ◽  
Contact Measurement

With the continuous progress of computer and laser measurement technology, non-contact measurement based on laser scanning technology has been more and more applied in the industrial production process. Since the 1990s, 3D laser scanning technology used as a new technology has been developed rapidly. The 3D laser scanning technology, also known as High Definition Surveying (HDS), was based on the principle of laser ranging. The technology on the surface of a measured object can record some features of large dense points, including 3d coordinates, reflectance and texture information, so as to rapidly reconstruct 3D models of a measured target and various map data such as the line, the surface and the body. Meanwhile, it is a revolutionary leap that the technology improves the traditional single point measurement to the surface measurement, and realizes the digital reconstruction of the objects. Especially, for some conditions such as contact measurement and complex component detection that cannot be measured, 3D laser scanning technology has a natural advantage in the field of industrial design and measurement .

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