Paper 6: Design Tolerances in Laser Measurement Systems

1968 ◽  
Vol 183 (4) ◽  
pp. 29-33
Author(s):  
W. R. C. Rowley ◽  
D. C. Wilson
Keyword(s):  
Laser Source ◽  
Laser Measurement ◽  
Measurement Systems ◽  
Interferometric Measurement

Interferometric measurement of length by fringe-counting, using a laser source, is a precision technique suitable for both engineering and laboratory applications. The limitations of such systems, in respect of speed and straightness of movement, are considered. Equations are given to assist the specification of the optical requirements and mechanical tolerances.

scholarly journals Development of a Compact Three-Degree-of-Freedom Laser Measurement System with Self-Wavelength Correction for Displacement Feedback of a Nanopositioning Stage

2018 ◽  
Vol 8 (11) ◽  
pp. 2209 ◽  
Author(s):  
Yindi Cai ◽  
Zhifeng Lou ◽  
Siying Ling ◽  
Bo-syun Liao ◽  
Kuang-chao Fan
Keyword(s):  
Laser Diode ◽  
Low Cost ◽  
Michelson Interferometer ◽  
Optical Path Difference ◽  
Path Difference ◽  
Degree Of Freedom ◽  
Laser Source ◽  
Laser Measurement ◽  
Length Unit ◽  
Three Degree Of Freedom

This paper presents a miniature three-degree-of-freedom laser measurement (3DOFLM) system for displacement feedback and error compensation of a nanopositioning stage. The 3DOFLM system is composed of a miniature Michelson interferometer (MMI) kit, a wavelength corrector kit, and a miniature autocollimator kit. A low-cost laser diode is employed as the laser source. The motion of the stage can cause an optical path difference in the MMI kit so as to produce interference fringes. The interference signals with a phase interval of 90° due to the phase control are detected by four photodetectors. The wavelength corrector kit, based on the grating diffraction principle and the autocollimation principle, provides real-time correction of the laser diode wavelength, which is the length unit of the MMI kit. The miniature autocollimator kit based on the autocollimation principle is employed to measure angular errors and compensate induced Abbe error of the moving table. The developed 3DOFLM system was constructed with dimensions of 80 mm (x) × 90 mm (y) × 20 mm (z) so that it could be embedded into the nanopositioning stage. A series of calibration and comparison experiments were carried out to test the performance of this system.

Accuracy of Commercially Available Laser Measurement Systems

CIRP Annals ◽  
1982 ◽  
Vol 31 (1) ◽  
pp. 427-429 ◽  
Author(s):  
P.H.J. Schellekens ◽  
J. Koning ◽  
P.C. Veenstra
Keyword(s):  
Laser Measurement ◽  
Measurement Systems

scholarly journals TEP Rail Head Profile Trolley - test results of the laser measurement system

2016 ◽  
Vol 2016 (12) ◽  
pp. 9-16
Author(s):  
Marcin Kowalski
Keyword(s):  
Research And Development ◽  
Measurement System ◽  
Optical Measurement ◽  
3D Models ◽  
Test Results ◽  
Laser Measurement ◽  
Research Project ◽  
Laser Measurement System ◽  
Measurement Systems ◽  
Rail Head

The article describes the results of research and development undertaken to develop a compact, optical measurement system for measuring the elements of track infrastructure. The article describes the main features of the optical measurement systems and the results of the research project. The author presents two examples of the implementation of this technology in the portable diagnostic devices: electronic trolley and in the toll for the creation of 3D models of turnout crossings.

Use of Laser Measurement Systems for Out-of-Roundness Check of ASME BVP Section VIII Div.1 Pressure Vessels

2014 ◽  
Author(s):  
Barry Millet ◽  
Patrizio Di Lillo ◽  
Richard Whipple ◽  
Kenneth Kirkpatrick ◽  
George Miller
Keyword(s):  
Cost Effective ◽  
External Pressure ◽  
Pressure Vessels ◽  
Laser Measurement ◽  
Measuring Systems ◽  
Measurement Systems ◽  
Cost Effective Method ◽  
Division 1 ◽  
Asme Code ◽  
Section Viii

Since the 1956 Edition of the ASME Boiler and Pressure Vessel Code Section VIII (ASME B&PV Code) [1], the Out-of-Roundness of circular sections of pressure vessels subject to external pressure have been inspected using a segmental template per paragraph UG-80(b)(2). Newly approved ASME Code Case 2789 “Laser Measurement for Out-of-Roundness Section VIII, Division 1” to the ASME B&PV Code expands the out of roundness checking to allow the use of laser measurement systems. Today with large vessels approaching 60 feet (18.2 m) in diameter, laser measuring systems allow an expeditious and cost effective method of inspection for out-of-roundness. The Code Case allows the fabricator to use measurements obtained from laser measuring to either verify the vessel in the arc segments or the entire vessel circumference is held to a circularity tolerance. The second option is similar to the requirements of European Standard EN 13445 (EN 13445) [2] which uses circularity. This paper will explore the origin and objective of the template and presents how laser measuring systems make use of the latest technology available to check for out-of-roundness. The paper will address laser measuring systems, procedures for taking measurements, and processing of the data into a format that can be verified by Authorized Inspectors.

Calibration Using Cylindrical Artifacts for 3D Laser Measurement System

2015 ◽  
Vol 9 (5) ◽  
pp. 546-550 ◽  
Author(s):  
Kazuhiro Enami ◽  
Keyword(s):  
Measurement System ◽  
Calibration Method ◽  
Calibration System ◽  
Laser Measurement ◽  
Laser Measurement System ◽  
Measurement Systems

We propose a new calibration method for 3D laser measurement systems used for inspecting the insides of industrial parts such as vessels and pipes. We developed the proposed calibration system using a cylindrical artifact such that the calibration is simple and easy to perform. We simulated and analyzed the proposed cylindrical artifact calibration method and the results demonstrate its adequacy.

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