Development and Practicality of a Scanning Point Autofocus Instrument for High Speed Areal Surface Texture Measurement

2014 ◽  
Vol 1017 ◽  
pp. 675-680 ◽  
Author(s):  
Katsuhiro Miura ◽  
Atsuko Nose ◽  
Hirofumi Suzuki ◽  
Mutsumi Okada
Keyword(s):  
High Precision ◽  
Surface Texture ◽  
High Speed ◽  
Measurement Time ◽  
Large Area ◽  
Texture Measurement ◽  
Index Measurement ◽  
3D Surface Texture ◽  
Areal Surface ◽  
Quantitative Evaluations

A point autofocus instrument (PAI) is widely used for the roughness and contour measurement of various precision processing surfaces, because it is capable of measuring a large area in high precision. The only disadvantage of PAI is to require a long measurement time. Its conventional index measurement stops the scanning stage in order to obtain each coordinate value of the fixed sampling pitch. Hence, it was necessary to develop a scanning point autofocus instrument (SPAI) which can obtain coordinate values while the scanning stage is moving. As an achievement of the development, the SPAI offers 26 times faster measurement speed than that of the index measurement with equivalent accuracy. The SPAI easily measures 3D surface texture and provides quantitative evaluations of the precision processing surfaces.

High-Speed Noncontact Profiling of Pavement Surface Texture and Its Significance

1986 ◽  
Vol 108 (3) ◽  
pp. 455-461
Author(s):  
J. C. Wambold ◽  
J. J. Henry
Keyword(s):  
Surface Texture ◽  
High Speed ◽  
Large Scale ◽  
Vision System ◽  
Small Scale ◽  
Skid Resistance ◽  
Texture Measurement ◽  
Pavement Surface ◽  
Texture Characteristics ◽  
Regression Techniques

It is generally agreed that the friction between a tire and a wet pavement (skid resistance) is controlled by the surface texture characteristics. Therefore, by measuring the relevant parameters describing texture, or by measuring a physical process dependent on texture, regression techniques can be used to relate skid resistance to the chosen texture parameter or process. Two scales of texture are of particular importance: microtexture (small-scale asperities) and macrotexture (large-scale asperities). This paper describes work performed to: (1) review candidate macrotexture and microtexture measurement methods that can be made at highway speeds (at or about 64 km/h [40 mph]), which are presently used or have potential for use in pavement texture measurement; (2) design and build a prototype of the most promising method; and (3) evaluate the effects of pavement surface texture on skid resistance. A prototype noncontact vision system that makes texture measurements at highway speeds was developed, and several improvements were made to upgrade the system to provide an improved prototype. Both hardware and software enhancements have yielded a texture measurement system that can obtain pavement macrotexture data in a fast, efficient, and reliable way.

Traceability for Areal Surface Texture Measurement

2010 ◽  
Vol 437 ◽  
pp. 121-125 ◽  
Author(s):  
Richard Leach ◽  
Claudiu Giusca ◽  
Kazuya Naoi
Keyword(s):  
Surface Texture ◽  
Vertical Displacement ◽  
National Physical Laboratory ◽  
Air Bearing ◽  
Texture Measurement ◽  
Physical Laboratory ◽  
Working Volume ◽  
Definition Of ◽  
Laser Interferometers ◽  
Areal Surface

The deterministic structuring of a surface is having a profound effect on many industrial products by allowing the manufacturer to significantly alter the way in which a surface functions. This has led to a clear need in industry and academia for traceable areal surface texture measurements. To address this need traceable transfer artefacts and primary instrumentation are required. The National Physical Laboratory (NPL) is working on two projects – one to develop areal transfer artefacts and one to develop a traceable areal surface texture measuring instrument. The authors describe the development of the artefacts and instrument, and present some of the challenges that are still required to be able to offer an areal traceability measurement service to industry. The instrument has a working volume of 8 mm  8 mm  0.1 mm and uses a co-planar air-bearing slideway to move the sample. It also uses a novel vertical displacement measuring probe, incorporating an air-bearing and an electromagnetic force control mechanism. The motions of the slideway and the probe are measured by laser interferometers thus ensuring traceability of the measurements to the definition of the metre. The artefacts were manufactured using a range of machining technologies and in a range of geometries suitable for stylus and optical based instruments.

Development of a roughness measurement standard with irregular surface topography for improving 3D surface texture measurement

2009 ◽  
Vol 20 (8) ◽  
pp. 084023 ◽  
Author(s):  
Kentaro Nemoto ◽  
Kazuhisa Yanagi ◽  
Masato Aketagawa ◽  
Ichiro Yoshida ◽  
Michimasa Uchidate ◽  
...  
Keyword(s):  
Surface Topography ◽  
Surface Texture ◽  
Irregular Surface ◽  
Roughness Measurement ◽  
Measurement Standard ◽  
Texture Measurement ◽  
3D Surface ◽  
3D Surface Texture

A Kind of Non-Contact Measurement System for Areal Surface Texture

2011 ◽  
Vol 189-193 ◽  
pp. 1263-1270 ◽  
Author(s):  
Sheng Huai Wang ◽  
Yu Rong Chen ◽  
Tie Bang Xie
Keyword(s):  
Optical Microscopy ◽  
Measurement System ◽  
Surface Texture ◽  
Imaging System ◽  
Microscopy Imaging ◽  
Contact Measurement ◽  
Displacement System ◽  
Hardware Circuit ◽  
3D Surface Texture ◽  
Areal Surface

For the measurement of areal surface texture, a non-contact measurement method for areal surface texture based on the co-integration of optical microscopy image measurement and white light microscopy interference measurement is proposed, which measures not only 2D size of length but also 3D surface texture. Based on this method, a 2D&3D optical microscopy measurement system for areal surface texture has been developed. It consists of compound optical microscopy imaging system, 3D precision displacement system, hardware circuit, and corresponding software. The practicality and effectiveness of the proposed method of measurement have been verified by the measurement results.

scholarly journals Variable step control to improve scanning speed of gene sequencing stage

2021 ◽  
pp. 002029402110022
Author(s):  
Xiaohua Zhou ◽  
Jianbin Zheng ◽  
Xiaoming Wang ◽  
Wenda Niu ◽  
Tongjian Guo
Keyword(s):  
Motion Control ◽  
High Precision ◽  
High Speed ◽  
Stable State ◽  
Gene Sequencing ◽  
Scanning Speed ◽  
Settling Time ◽  
Step Motion ◽  
Variable Step ◽  
Step Control

High-speed scanning is a huge challenge to the motion control of step-scanning gene sequencing stage. The stage should achieve high-precision position stability with minimal settling time for each step. The existing step-scanning scheme usually bases on fixed-step motion control, which has limited means to reduce the time cost of approaching the desired position and keeping high-precision position stability. In this work, we focus on shortening the settling time of stepping motion and propose a novel variable step control method to increase the scanning speed of gene sequencing stage. Specifically, the variable step control stabilizes the stage at any position in a steady-state interval rather than the desired position on each step, so that reduces the settling time. The resulting step-length error is compensated in the next acceleration and deceleration process of stepping to avoid the accumulation of errors. We explicitly described the working process of the step-scanning gene sequencer and designed the PID control structure used in the variable step control for the gene sequencing stage. The simulation was performed to check the performance and stability of the variable step control. Under the conditions of the variable step control where the IMA6000 gene sequencer prototype was evaluated extensively. The experimental results show that the real gene sequencer can step 1.54 mm in 50 ms period, and maintain a high-precision stable state less than 30 nm standard deviation in the following 10 ms period. The proposed method performs well on the gene sequencing stage.

scholarly journals High-speed high-efficiency large-area resonant cavity enhanced p-i-n photodiodes for multimode fiber communications

2001 ◽  
Vol 13 (12) ◽  
pp. 1349-1351 ◽  
Author(s):  
M. Gokkavas ◽  
O. Dosunmu ◽  
M.S. Unlu ◽  
G. Ulu ◽  
R.P. Mirin ◽  
...  
Keyword(s):  
High Speed ◽  
High Efficiency ◽  
Resonant Cavity ◽  
Multimode Fiber ◽  
Large Area ◽  
Fiber Communications
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