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Search Publications by: Bala Muralikrishnan (Fed)

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Displaying 76 - 100 of 170

Report on the May 2016 ASTM E57.02 instrument runoff at NIST, Part 2 - NIST realization of test procedures and uncertainties in the reference lengths

October 19, 2016
Author(s)
Balasubramanian Muralikrishnan, Prem K. Rachakonda, Katharine M. Shilling, Vincent D. Lee, Christopher J. Blackburn, Daniel S. Sawyer, Geraldine S. Cheok, Luc Cournoyer
There is ongoing activity within ASTM E57.02 working group WK43218 [1] to develop a documentary standard for point-to-point distance performance evaluation of 3D imaging systems. The Dimensional Metrology Group (DMG) at the National Institute of Standards

Targets for Relative Range Error Measurement of 3D Imaging Systems.

July 25, 2016
Author(s)
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Katharine M. Shilling, Geraldine S. Cheok, Vincent D. Lee, Christopher J. Blackburn, Dennis S. Everett, Daniel S. Sawyer
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) is performing research to support the development of documentary standards within ASTM E57 for the point-to-point performance evaluation of 3D imaging

Laser Trackers for Large Scale Dimensional Metrology: A Review

March 25, 2016
Author(s)
Balasubramanian Muralikrishnan, Steven D. Phillips, Daniel S. Sawyer
Thirty years since their invention, laser trackers are now recognized as the measurement tool of choice in the manufacture and assembly of large components. While their general design, i.e., a ranging unit on a two-axis gimbal, has not changed

Performance evaluation of a laser tracker hand held touch probe

November 4, 2015
Author(s)
Bala Muralikrishnan, Christopher J. Blackburn, Prem K. Rachakonda, Daniel S. Sawyer
Hand-held touch probes and laser scanners are increasing the scope and applicability of laser trackers. While methods to evaluate the performance of laser trackers in conjunction with spherically-mounted retro-reflectors (SMRs) are well established

Evaluation of the Range Performance of Laser Scanners Using Non-planar Targets.

November 1, 2015
Author(s)
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Craig M. Shakarji, Vincent D. Lee, Daniel S. Sawyer
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) is supporting the development of documentary standards for performance evaluation of Laser scanners. This evaluation could be performed by determining the

Towards the Development of a Documentary Standard for Derived-Point to Derived-Point Distance Performance Evaluation of Spherical Coordinate 3D Imaging Systems

October 30, 2015
Author(s)
Balasubramanian Muralikrishnan, Katharine M. Shilling, Prem K. Rachakonda, Wei Ren, Vincent D. Lee, Daniel S. Sawyer
This paper describes ongoing research work within the Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) in support of the development of a documentary standard for derived-point to derived-point distance

Techniques to Evaluate Laser Scanners for Advanced Manufacturing Applications

July 23, 2015
Author(s)
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Katharine M. Shilling, Daniel S. Sawyer, Geraldine S. Cheok, Kamel S. Saidi
Laser scanners have become indispensable tools for fast and accurate 3D image acquisition applications such as part inspection, reverse engineering, cultural heritage digitization, surveying, automotive robotic navigation etc. The Dimensional Metrology

Volumetric Performance Evaluation of a Laser Scanner Based on Geometric Error Model

January 5, 2015
Author(s)
Balasubramanian Muralikrishnan, Massimiliano M. Ferrucci, Daniel S. Sawyer, Grant Gerner, Vincent D. Lee, Christopher J. Blackburn, Steven D. Phillips, Yuri Yakovlev, Andrey Astrelin, Spike Milligan, John Palmateer
We discuss a geometric error model for those large volume laser scanners that have the laser source and a spinning prism mirror mounted on a platform that can rotate about the vertical axis. We describe the terms that constitute the model, address their

In-situ Temperature Calibration Capability for Dimensional Metrology

December 15, 2014
Author(s)
Prem K. Rachakonda, Daniel S. Sawyer, Balasubramanian Muralikrishnan, Christopher J. Blackburn, Craig M. Shakarji, Gregory F. Strouse, Steven D. Phillips
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) has developed a new in-situ temperature calibration system. This paper discusses the system components, an in-situ calibration procedure, the uncertainty

In-situ Temperature Calibration Capability for Dimensional Metrology

December 1, 2014
Author(s)
Prem K. Rachakonda, Daniel S. Sawyer, Balasubramanian Muralikrishnan, Christopher J. Blackburn, Craig M. Shakarji, Gregory F. Strouse, Steven D. Phillips
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) has the capability to perform large range dimensional measurements in a facility, called the Tape Tunnel. The Tape Tunnel is equipped with a 60 m long steel

A Method of Determining Sphere Center to Center Distance Using Laser Trackers For Evaluating Laser Scanners.

November 11, 2014
Author(s)
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Vincent D. Lee, Daniel S. Sawyer, Steven D. Phillips, John Palmateer
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) is involved in the development of documentary standards for volumetric performance evaluation of laser scanners. Typical evaluation of these scanners

Laser scanner two-face errors on spherical targets

November 11, 2014
Author(s)
Balasubramanian Muralikrishnan, Katharine M. Shilling, Daniel S. Sawyer, Prem K. Rachakonda, Vincent D. Lee, Steven D. Phillips, Geraldine S. Cheok, Kamel S. Saidi
Geometric misalignments within the construction of a laser scanner such as offsets, tilts, and eccentricities, result in systematic errors in the measured point coordinates (range and angles). Many of these sources of error are sensitive to two-face

POINT REMOVAL FOR FITTING SPHERES TO 3-D LASER SCANNER DATA

November 11, 2014
Author(s)
Katharine M. Shilling, Balasubramanian Muralikrishnan, Daniel S. Sawyer
The proliferation of laser scanners in a number of industries such as the metrology of large artifacts, digitization and reverse engineering, historical preservation and archiving has led to the need for documentary Standards to establish and compare the