U.S. flag

An official website of the United States government

Search Publications by: Theodore D. Doiron (Assoc)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 1 - 25 of 67

Sphere Diameter Interferometry with Nanometer Uncertainty

February 19, 2020
Author(s)
Eric S. Stanfield, John R. Stoup, Michael P. Braine, Theodore D. Doiron
In this paper we present both the design details and uncertainty budget for a National Institute of Standards and Technology (NIST)-developed high-accuracy Fizeau-type interferometer specifically adapted to measurement sphere diameter. To do this, we

Dimensional Measurement Uncertainty from Data. Part 2: Uncertainty R&R

July 1, 2016
Author(s)
Theodore D. Doiron
While check standards will eventually give the most accurate uncertainty for a calibration procedure, the time and expense can be discouraging. Another common method, standard Gage Repeatability and Reproducibility study does not produce anything like the

Dimensional Review of Scales for Forensic Photography

November 25, 2015
Author(s)
Massimiliano Ferrucci, Theodore D. Doiron, Robert M. Thompson, John Jones, Adam J. Freeman, Janice A. Neiman
Scales for forensic photography provide a geometrical reference in the photographic documentation of a crime scene. A common scale used by investigators is a plastic, L-shaped ruler that allows for a dimensional reference in the photographic documentation

Using Check Standard Data to Simplify Uncertainty Estimates

July 1, 2015
Author(s)
Theodore D. Doiron
Uncertainty has proven difficult to implement in calibrations labs. The subject has mathematics and statistics that are part of normal scientific research but are seldom found among working metrologists in small calibration labs. There is, however, a

Two Applications of Small Feature Dimensional Measurements on a CMM with a Fiber Probe

September 4, 2013
Author(s)
Eric S. Stanfield, Bala Muralikrishnan, Theodore D. Doiron, Xiaoyu Alan Zheng, Shahram Orandi, david Duquette
We describe two interesting applications of dimensional measurements performed using a contact fiber probe on a commercial Coordinate Measuring Machine (CMM). Both examples involve artifacts that serve as material standards and contain features in the 100

Applications of Profile Filtering in the Dimensional Metrology of Fuel Cell Plates

May 14, 2013
Author(s)
Balasubramanian Muralikrishnan, Wei Ren, Eric S. Stanfield, Dennis S. Everett, Xiaoyu A. Zheng, Theodore D. Doiron
We describe the application of several surface profile filters as an enabling tool in the dimensional measurements of an engineering artifact, namely, a fuel cell plate. We recently reported work on the development of a non-contact system for dimensional

High Accuracy Measurements Using a Scanning System with a Single Point Triangulation Sensor

May 13, 2013
Author(s)
Theodore D. Doiron, Wei Ren, Eric S. Stanfield, Balasubramanian Muralikrishnan, Christopher J. Blackburn
The capabilities of non-contact laser spot triangulation sensors for high accuracy measurements have slowly increased over the past decade, and now have usable resolution below 0.1 µm. The Dimensional Metrology Group has developed a simple scanning system

Performance Evaluation Experiments on a Laser Spot Triangulation Probe

November 25, 2011
Author(s)
Balasubramanian Muralikrishnan, Wei Ren, Dennis S. Everett, Eric S. Stanfield, Theodore D. Doiron
Laser triangulation probes are increasingly used for dimensional measurements in a variety of applications. At the National Institute of Standards and Technology, we have recently explored the use of laser spot triangulation probes to determine dimensional

NON-CONTACT DIMENSIONAL MEASUREMENTS OF BIPOLAR FUEL CELL PLATES

November 15, 2011
Author(s)
Balasubramanian Muralikrishnan, Wei Ren, Dennis S. Everett, Eric S. Stanfield, Theodore D. Doiron
Non-contact dimensional measurement of fuel cell plates is critical to the eventual rapid manufacture by supporting in-process measurement and control. This need has been identified by the Department of Energy’s Hydrogen Program, and by numerous

Dimensional Metrology of Bipolar Fuel Cell Plates Using Laser Spot Triangulation Probes

March 22, 2011
Author(s)
Balasubramanian Muralikrishnan, Wei Ren, Dennis S. Everett, Eric S. Stanfield, Theodore D. Doiron
As in any engineering component, manufacturing a bipolar fuel cell plate for a polymer electrolyte membrane (PEM) hydrogen fuel cell power stack to within its stated design tolerances is critical in achieving the intended function. In a bipolar fuel cell

Gauge Blocks - A Zombie Technology

May 1, 2008
Author(s)
Theodore D. Doiron
Gauge blocks have been the primary method for disseminating length traceability for over 100 years. Their longevity was based on two things: it was relatively inexpensive to deliver very high accuracy to users, and the technical limitation that the range

Early Results From the NIST M48 CMM in the New AML Facility

March 3, 2006
Author(s)
John R. Stoup, Bryon S. Faust, Theodore D. Doiron
The Advanced Measurement Laboratory at NIST in Gaithersburg has already provided real, measurable improvement in some dimensional metrology measurement processes at NIST, most notably in the performance of the NIST Moore M48 coordinate measuring machine1