Multiple Tones In Power Calibration
Author(s): Alex Dorchak, Warren Wong
Abstract/Introduction:
Increased usage of nonlinear loads such as personal computers, laser printers, and motor controllers is adversely affecting the quality of power distributed within a business facility. Of particular concern are the harmonics introduced on the power line by these loads, causing loss in productivity and potential safety issues. Another issue is the accuracy of revenue meters in the presence of these harmonics. Facilities personnel are purchasing and using sophisticated power quality monitoring equipment to quantify these problems. As with all precision test and measurement equipment, these instruments should be routinely verified and calibrated. International standards are being established to define the test requirements for these devices. This paper gives an overview of the power industry and makes a case for expediting the adoption of these standards to provide adequate traceability of power quality instrumentation and revenue metering.
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Document ID:
8A26C1E0
Operation, Calibration And Use Of Optical Time Domain Reflectometers
Author(s): Jerry m Benson, Brian Walker
Abstract/Introduction:
The Optical Time Domain Reflectometer ( OTDR ) is one of the most versatile and widely used pieces of fibre optic test equipment. The instrument is used both in the laboratory and the field to measure the attenuation along lengths of fibre and to locate the position of breaks, defects and other features such as reflections from joints. This paper describes their principle operation and ways of calibrating them. It also give some pointers on how to use them to obtain the most accurate results.
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Document ID:
1F1FE3F9
Simnet - A Metrology Network For The Americas
Author(s): William Anderson, Nile Oldham, Mark Parker
Abstract/Introduction:
SIMnet is an Internet-based video conferencing system developed to facilitate international comparisons, and foster collaborations between national metrology laboratories. The system employs standard hardware and a special network server to allow audio, video, and data exchange between multiple participants.
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Document ID:
8C19370C
The Impact Of Smart Calibrators On Calibration Management Software
Author(s): Randy P. Paroda, Blaine E. Clapper
Abstract/Introduction:
Over the past decade, thousands of manufacturers around the world have implemented calibration management software to schedule and track their calibration events and equipment maintenance. The primary drivers behind the implementations are compliance to regulations and quality standards and increased productivity and efficiency. For those same purposes, documenting process calibrators, or smart calibrators, are now being implemented in large numbers. The popularity of smart calibrators has introduced new challenges to software developers. The software is now expected to communicate with the calibrators to create a truly paperless calibration process, while maintaining the flexibility and record tracking capabilities that manufacturers need to accommodate non-process calibrations and to meet regulatory standards. Those challenges are discussed in detail in this presentation.
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Document ID:
56EE4FDE
Streamlining Instrument Calibration With Asset Management Software
Author(s): Israel E. Alguindigue, Todd A. Gates
Abstract/Introduction:
An asset management system integrates diverse technologies and processes, each with different data collection and data processing requirements, to provide three important functions that help reduce maintenance costs. It collects data generated by smart field instruments, organizes data for various maintenance functions, and monitors for early warning signs of field device stress or deterioration so that corrective action can be taken before a serious failure occurs. Asset management software provides on-line access to field instrumentation from a single platform and has the ability to gather maintenance-related information about plant devices in a single database. It allows users to configure, monitor, and troubleshoot smart instruments, as well as to accurately document all maintenance activities, including calibration.
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Document ID:
039FFC9A
The Three Axis Cube Positioner Boresights Multiple Target Simulators
Author(s): J. R. Barr
Abstract/Introduction:
The Three-Axis Cube Positioner was developed to generate Angle Standards of Reference in Three Mutually Orthogonal Directions on one robust kinematic platform. This Standard provides an efficient and microradian accurate means to correlate, boresight and calibrate one or more test targets, target simulators, and/or optical transfer standard measurement instruments to a products three coordinate spatial datum. Advanced Military Tactical and Strategic Electro-Optical Sensor and Targeting Systems can sense a given target with increased range and require more stringent boresight tolerances. The systems may incorporate more than one sensor subsystem and the multiple sensors may point in different directions. These multiple sensors must be correlated to a common datum set, namely the spacecraft or aircraft coordinate system. In addition, several target simulators may be required for ground based testing, simultaneously, to verify acceptable performance from many different directions with multiple targets at various simulated distances (Fields of View, FOV). The processes are inside-out, and developed using the Three-Axis Cube Positioner standard.
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Document ID:
1588CA28
The Accurate Capture Of Ultra-Dim Irradiance Using Advanced Radiometric Metrology Processes
Author(s): J. R. Barr
Abstract/Introduction:
The processes developed to accurately measure and calibrate the radiation emitted from advanced Electro-Optical Target Simulators are based on: 1) Selecting the best reference datum for the purpose 2) Millidegree accurate thermometry 3) Primary reference blackbody cavities with characterized emissivity 4) A 4th generation Radiometric Telescope 5) NIST Standard Lamps of Spectral Irradiance 6) Capability studies and 7) Uncertainty analysis. Advanced Military Tactical and Strategic Electro-Optical Sensor Systems can sense a given target with increased range in more than one spectral band from UV, through mid wave infrared (MWIR) to long wave infrared (LWIR). The multi spectral operation can also be simultaneous and through a common system aperture. Also, some advanced tactical FLIR systems incorporate laser range finding and target designation through the common aperture at more than one wavelength (eye safe and weapon level).
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Document ID:
67AE5D8F
Statistical Process Control (SPC) For Coordinate Measurement Machines. Using SPC And Monitoring Of Standard Artifacts To Determine And Control Measurement Uncertainty In A Controlled Environment
Author(s): Rudolph N. Escher, Jr.
Abstract/Introduction:
The application of process capability analysis, using designed experiments, and gage capability studies as they apply to coordinate measurement machine (CMM) uncertainty analysis and control will be demonstrated. The use of control standards in designed experiments, and the use of range charts and moving range charts to separate measurement error into its discrete components will be discussed. The method used to monitor and analyze the components of repeatability and reproducibility will be presented with specific emphasis on how to use control charts to determine and monitor CMM performance and capability, and stay within your uncertainty assumptions.
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Document ID:
0DE974E6
Ormc 2000
Author(s): Rudolph N. Escher, Jr.
Abstract/Introduction:
Why measure? - Verify compliance with specifications or regulations. - Optimize production process: Minimize cost & Maximize Quality - Make informed decisions. - Be competitive - ISO certification. - Learn about Nature & instrumentation - Make Scientific, Research & Development endeavors meaningful. Measurement Characteristics - Measurand - The quantity to be measured specified by a description of a quantity realized quantity - often an approximation - True value and corrected value result corrected for the difference predicts what it would have been
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Document ID:
38B944F8
A Systems Approach To Ste And Calibration
Author(s): Brian Willoughby
Abstract/Introduction:
Todays in the military systems development environment things have changed considerably from what they were even just a few years ago. Today we no longer buy black boxes or standalone weapons but rather we buy integrated weapons system. This provides a great challenge to the Special Test Equipment (STE) community and hence the calibration community as well. The interactions between subsystems (and hence test equipment as well) produce conditions of tolerance stack up which can produce out of spec test results from subassemblies that are within spec.
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Document ID:
014EAA6D
A New Millenium Of Measurements
Author(s): Alan R. Robertson
Abstract/Introduction:
This paper explains the international system of metrology and discusses how the system is adapting to the globalization of trade and the need to eliminate technical barriers to trade as we move into the new millennium. The paper also points to some of the many new and exciting challenges that are arising at the frontiers of measurement science.
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Document ID:
593C9DF3
Time Domain Characterisation Of Modern Time And Frequency Standards
Author(s): Richard Percival
Abstract/Introduction:
The article is an attempt at explaining the basic theory and practice behind frequency calibration in the time domain. There are many different ways of characterising the frequency accuracy and stability of a standard in the time domain. However, successful characterisation involves, amongst other things, consideration of the various noise processes generated by frequency standards, understanding the multitude of statistical methods available, following a quality calibration procedure (such as NAMAS) and the efficient logging of the results. This paper seeks to explain and clarify the terminology used to specify and characterise modern Time and Frequency Standards. It shows the difference between accuracy and stability, expounds the need for appropriate reference standards, charts the development of the Allen Variance and its cousins, gives detailed information into their respective advantages and disadvantages and shows where each may be most appropriately used. To aid in understanding how time domain measurements are taken, the reader is led through the procedure used in-house by the company to characterise and calibrate their range of time and frequency standards. This is both for internal (research and development) and external (calibration certification for customers) use.
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Document ID:
7EE23BAA
Effective Measurement Of Business Performance
Author(s): Philip Stein
Abstract/Introduction:
In this paper, we introduce some of the technical measurement tools that have long served the scientific community, and show that they apply equally well to measurements of non-financial business performance. Many recent trends in business have pointed towards using non-financial measurements as well as the more traditional accounting measures to assess, report, and drive business success. The Criteria for Excellence of the Malcolm Baldrige National Quality Award have always stressed customer satisfaction, process excellence, employee satisfaction and other leading metrics that can predict future performance rather than just memorialize past accomplishments.
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Document ID:
2F753E6D
Mems Devices For Force Measurement Applications
Author(s): Thomas Kenny
Abstract/Introduction:
In recent years, many researchers have adapted lithography, deposition and etching techniques from the IC processing community for the fabrication of micromechanical sensors. Many of the signals that these sensors are intended to detect are expressed as forces which stress or deflect the micromechanical structure. As sensors are miniaturized, these forces naturally become smaller, and techniques for detection are required to improve. Our research group has been engaged in a variety of activities, all of which share an interest in improving the force detection capability of microinstruments. In this paper, an overview of these activities will be presented, beginning with simple straingauge sensors (micronewtons), sensors based on tunneling displacement transducers (nanonewtons), AFM cantilevers (piconewtons), and ultra thin force sensing cantilevers (attonewtons). Opportunities for exciting scientific measurements will be highlighted, and challenges for application of MEMS devices to these measurements will be discussed.
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Document ID:
F1839099
Biomedical Applications Of Mems
Author(s): Jack W. Judy
Abstract/Introduction:
Micromachining and MEMS technologies can be used to produce complex electrical, mechanical, fluidic, thermal, optical, and magnetic structures, devices, and systems on a scale ranging from organs to subcellular organelles. This miniaturization ability has enabled MEMS to be applied in many areas of biology, medicine, and biomedical engineering - a field generally referred to as BioMEMS. The future looks bright for BioMEMS to realize (1) microsensor arrays that act as an electronic nose or tongue, (2) microfabricated neural systems capable of controlling motor or sensory prosthetic devices, (3) painless microsurgical tools, and (4) complete microfluidic systems for total chemical or genetic analyses.
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Document ID:
E764109E
A Model For Selecting Cots Software And The Process Of Making The Selection Successful
Author(s): John Grajera
Abstract/Introduction:
This paper explains the process of selecting, installing and bringing on-line Commercial Off The Shelf (COTS) software to satisfy calibration laboratory database requirements. The subjects covered are computer hardware and software, selecting a COTS vendor, installing the COTS database application, configuring the application, training the users, data population and testing the COTS application for correctness.
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Document ID:
22D37CF4
Volumetric Calibration And Compensation Of Cnc Machine Tools
Author(s): Charles Wang, Bob Griffin, John Janeczko
Abstract/Introduction:
To achieve higher position accuracy of a machine tool, it is important to measure the volumetric errors and to compensate the volumetric errors provided that the machine tool is repeatable. Described here is a vector method developed by Optodyne. Using the Optodynes laser calibration system and the vector method, the volumetric errors of a Giddings & Lewis, model RAM 630 machine center have been measured. The measured volumetric errors were used to compensate the machine errors and achieved higher volumetric accuracy. The time required to compensate the machine using the vector method is significantly less than that using conventional measurement procedures.
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Document ID:
C8F7A9A5
What Is A Sphere? How Are They Made? How Are They Measured And How Are They Used In Metrology?
Abstract/Introduction:
The word sphere first appeared in the written English language in 1300. The early concept of a sphere was that of a radius being rotated 360 degrees around a line axis terminating in two poles, see (Figure # 1. A.). The modern technical definition of a sphere might be a three dimensional closed body with all points on its surface at an equal distance from a single central point, see (Figure # 1. B.). There are two basic techniques used for finishing precision balls.
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Document ID:
068B53BA
Wing Dimensional Measurement System Standoff Land Attack Missile Expanded Response Slam( Er)
Author(s): David m. Rohde
Abstract/Introduction:
The latest variant of the Standoff Land Attack Missile (SLAM), the Standoff Land Attack Missile Expanded Response (SLAM ER), utilizes planer wings similar in shape and size to those used on the TOMAHAWK Missile. Planer wings providing increased standoff capabilities replaced the cruciform wings currently used on SLAM. The requirement for 100% interchangeability of wings was established early in the program as a measure to prevent the need for matching wing sets during production and depot level maintenance. Wing hub angularity, incidence, twist, and profile are key factors in assuring wing interchangeability, with wing hub angularity and incidence being the most critical. Each wing is allowed a hub angularity tolerance of only .003, and only .175 of incidence.
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Document ID:
2527DABF
Measurement Uncertainty Misconceptions Mums The Problem
Author(s): Ricardo A. Nicholas
Abstract/Introduction:
The meanings of certain measurement uncertainty terms and treatments are occasionally a challenge to understand. This can lead to misconceptions, which if left uncorrected and communicated to others, can seriously compound the problem. This paper intends to clarify a few of these terms and treatments. Presented topics include: Systematic versus Random Effect (Error), Systematic versus Random Uncertainty, Type A versus Type B Uncertainty Evaluations and Components, Relative Uncertainty, Type B Degrees of Freedom, and The Treatment of Known Systematic Effects (Errors). The clarifications made are consistent with the ISO 5 and ANSI/NCSL 3 Guides to the Expression of Uncertainty in Measurement. Explanations are only as complex as necessary to sufficiently clarify the terms and treatments.
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Document ID:
C32A9A39
Estimating Category B Degrees Of Freedom
Author(s): Howard Castrup
Abstract/Introduction:
A method is presented for estimating uncertainties in cases where samples of data are unavailable. The method includes a formalism that provides a structure for extracting information from the measurement experience of scientific or technical personnel. This information is used to both estimate uncertainties and to approximate the degrees of freedom of the estimate. Using these results, confidence limits are developed that obviate the need for arbitrary coverage factors and misleading expanded uncertainties.
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Document ID:
3AB09258
An Application Of The Guide To Measurement Uncertainty
Author(s): David Deaver
Abstract/Introduction:
Do you understand how to apply the Guide to Measurement Uncertainty (GUM)? The analysis supporting the Primary Standards Labs accredited uncertainty claims for its 10MHz frequency reference is used to examine some of the differences in the various GUMs, the tradeoffs between using a simplified vs. a more rigorous approach, and how some of the difficult issues such as drift were handled. This analysis describes the uncertainty of the frequency of a Sulzer 2.5C ovenized oscillator and frequency doubler. It was chosen for presentation as a paper, not because it represents the state of the art for time and frequency measurements, rather because it contains some interesting aspects in the application of the GUM.
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Document ID:
F9FD2C7C
On An Improved Way Of Resolving Two Very Stable And Accurate Frequency Signals And The Benefits Conferred As A Result
Author(s): Richard Percival
Abstract/Introduction:
With the advance in accuracy and stability of modern atomic clocks, the need for a very precise method of detecting instabilities in their signals has arisen. Two hydrogen masers have a drift rate of phase due to the frequency difference of 1fs per second or 3.6ps per hour. Quartzlock have developed a state of the art frequency and time interval measurement system. The A7 combines the most advanced phase comparators and PC time interval counting techniques. Stable 32 Stability analysis software is included as standard, as is a 4 way distribution amplifier and a rubidium oscillator. Initial results with a hydrogen maser reference in a temperature controlled room gave an Allen Variance Noise Floor of 5E-14, 8E-15, 1.5E-15 and 3.5E-16 for 1s, 10s, 100s and 1000s averaging times (t). Drift is as low as 5ps/hr, with a temperature sensitivity of 10ps/C. A single shot rms. resolution of 0.3ps was also measured.
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Document ID:
0B4B9A16
3D Mems In Standard Processes: Fabrication, Quality Assurance, And Novel Measurement Microstructures
Author(s): Gisela Lin, Russell A. Lawton
Abstract/Introduction:
Three-dimensional MEMS microsystems that are commercially fabricated require minimal post-processing and are easily integrated with CMOS signal processing electronics. Measurements to evaluate the fabrication process (such as cross-sectional imaging and device performance characterization) provide much needed feedback in terms of reliability and quality assurance. MEMS technology is bringing a new class of microscale measurements to fruition. The relatively small size of MEMS microsystems offers the potential for higher fidelity recordings compared to macrosize counterparts, as illustrated in the measurement of muscle cell forces.
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Document ID:
9D7D64C8
Applications Of Microtechnology In Measurement Systems
Author(s): Douglas H. Baker, William P. Taylor
Abstract/Introduction:
Microelectromechanical Systems (MEMS), when viewed as a manufacturing technology tool, offers the potential for dramatic reduction in the size and cost of both sensors and actuators. In this paper the application of MEMS to both vacuum gauges and relays will be discussed. The vacuum gauge uses a combination of two micromachined pressure sensors to allow a single transducer to operate from 1 x 10-4 Torr to 103 Torr. In addition, a fully integrated magnetically actuated microrelay is described and packaging methods are discussed.
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Document ID:
7265157A
Computer Assisted Logistics And Test Equipment Calibration System Caltecs()
Author(s): Ronald Kirstatter, Tama Stevens, Jesse Martinez, Mark Kramer
Abstract/Introduction:
The Marine Corps has successfully implemented their first Automated Information System (AIS) modeled after AIS commercial best practices. To accomplish this we utilized the Marine Corps Common Hardware Suite (MCHS) with a customized Commercial Off The Shelf (COTS) software package designed for synergistic laboratory management. To meet the challenge of reduced manpower coupled with the loss of experience and corporate knowledge this robust system was forged to enhance mission driven requirements and readiness postures. Marine Forces Ground calibration workload requirements include a pool of 165,000 items, with only 45 man-years of workforce available. One key implementation goal of this AIS is to dramatically increase productivity. Another key goal is the implementation of a comprehensive quality program. The Marine Corps has adopted the American National Standard for Calibration (ANSI/NCSL Z540-1-1994) as the primary basis for criteria to ensure Marine Corps Calibration Laboratories are capable of performing required calibration measurements. Utilizing this AIS, quality training, personnel commitment, and a continuous improvement philosophy, to prepare all calibration laboratories for accreditation audits by the end of 2000.
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Document ID:
80A3EF83
Calibration - Science, Business, Or Both?
Author(s): Randy Fowler
Abstract/Introduction:
There is a part of the human race that is driven to make measurements - metrologists, and we are continually being bombarded with the how tos of making better measurements. Regardless of their organizations sphere of activities, metrologists are bound by the fact that whatever they do either makes money or contributes in some way to their organizations bottom line. Calibration becomes a meeting of science and business. The familiar issues of good measurement practice, traceability and uncertainty are joined by those of efficiency, throughput and return on investment. This paper examines the methods for making decisions based not only on the scientific aspect of calibration and metrology, but also on the business aspect. It includes discussion of issues such as maximizing throughput, the best utilization of staff skills, and the impact of the extent of automation in so called automated systems.
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Document ID:
5B974628
Uncertainty Issues Associated With A Very Large Capacity Flow Calibration Facility
Author(s): T. m. Kegel
Abstract/Introduction:
In the spring of 1999, CEESI began operation of a natural gas calibration facility located in Iowa with a maximum flow capability in excess of 2000 pounds per second. The flow standard is a parallel array of ten turbine meters. The traceability to NIST is achieved through the CEESI Colorado facility. This paper discusses aspects of the flow measurement traceability methodology and associated uncertainty analysis. The complete uncertainty analysis comprises many components. These include the measurements of pressure, temperature, and gas composition as well as flowrate. The data acquisition system and calculations of compressibility and flowrate also contribute uncertainty. This paper concerns only those components of uncertainty contributed by the flow measurement. The paper is divided into four sections. The first two sections briefly describe the flowmeter types and initial calibration process. The last two sections describe two measurement assurance programs that are underway.
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Document ID:
F8221312
A Laboratory Comparison Of The Calibration Of Two Turbine Flow Meters Mounted In Series
Abstract/Introduction:
A pair of one-inch turbine flow meters in series has been calibrated by several different agencies to establish and maintain satisfactory fluid flow measurements among DoD, industrial, and national standards laboratories. Participating countries included Canada, England, France, Germany, and the United States. Calibrations were nearly evenly split between volumetric and dynamic weighing methods. The deviation of the meter factor for each agency from the unweighted mean was resolved into a systematic and random error using Youden plots. Typical systematic errors were 0.1 percent or better and typical random errors were 0.03 percent or better.
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Document ID:
3692D16D
Realistic Flow Measurement Traceability - The Ford Flow Measurement Assurance Program Map()
Author(s): Richard W. Caron, Charles L. Britton
Abstract/Introduction:
Ford Motor Company is involved in accurately measuring the air mass flow rate into their internal combustion engines for meeting the required level of pollutant output and for improved fuel economy. In this endeavor, Ford has constructed many different flow stands which measure air mass flow rates during various development and manufacturing processes. To be assured that each flow stand is measuring the mass flow correctly, Ford has implemented a Measurement Assurance Program (MAP). This paper focuses on the Measurement Comparison Program (MCP) portion of the MAP. It describes the physical hardware (artifact) which consists of piping sections and three Critical Flow Venturis (CFV). The MAP artifact has been used for interlaboratory comparison.
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Document ID:
3BDB7FCC
The Practical Significance Of Electrical Harmonics
Author(s): Robert J. Gilleskie
Abstract/Introduction:
Harmonic distortion is a relatively new concern in the electric power industry and among end-users of electricity, its existence being primarily the result of the growing use of computers and other electronic equipment. Unfortunately, this relative newness has resulted in a misplaced significance of harmonics, some end-users being almost totally unaware of their existence, and others exaggerating their practical effects. This paper will consider some of the basic definitions of harmonics as well as their most common causes and methods of measurement. Next, it will present a realistic assessment of their effects, and the likelihood of their occurrence in the residential, commercial, and manufacturing environments. And for situations of excessive harmonics, it will discuss the most effective means of mitigation. It will then conclude with what the author believes should be a reasonable assessment of the significance of harmonics, and a practical approach to managing their effect on end-use equipment.
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Document ID:
CA19BF9E
Non-Invasive Method Of Measuring Distributed Impedance Of Neuron Fibers
Author(s): Boguslaw Kuszta, Cynthia Husted
Abstract/Introduction:
A method is proposed for non-invasively determining the impedance along a branch of a neuron tree using voltage sensitive dyes and fiber tree morphology obtained from computerized image analysis. Using the concept of Tellegen adjoint networks in combination with voltage changed allows effective impedance computation of selected fibers. The primary function of nerves is to process electrical (electrochemical?) signals. The velocity of signal propagation and computational capabilities of the nervous system depend on the impedances of the all branches of a dendritic tree. Despite the apparent triviality of computing the impedance as a ratio of the voltage drop along the fiber to the current in the fiber, real measurements are difficult and yield conflicting results. The main reasons for difficulties are the complex morphologies of dendritic trees and a lack of truly non-invasive methods of current injection and voltage measurements.
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Document ID:
ECB72ADB
Video Borescope Inspection System Vbis() Technology Advances To Support Extended Range Guided Munitions Ergm() Program
Author(s): Christopher Ange
Abstract/Introduction:
For more than 40 years, the optically based M3 Borescope had served as the standard device for gun bore examination. Todays technology far surpasses its limited capabilities. The M3 has become difficult to supply with spare parts 40 years after the design was conceived. It relies heavily on operator expertise and can not easily record inspection findings. This paper describes how VBIS was developed to offer remedies for M3 shortcomings and, in addition, meet ERGM requirements. This paper explains the need for enhanced gun barrel inspection and reporting driven particularly by concerns raised by the ERGM program. It was uncertain what damage the ERGM round and propelling change would inflict on 5/62 caliber barrel surfaces.
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Document ID:
70F0C9C0
A Practical Approach To Air Density Determination
Author(s): Randall m. Schoonover, Frank E.Jones, Richard Calkins
Abstract/Introduction:
Mass standards are used directly or indirectly via the electronic balance in many common measurement applications such as mass, density, volumetric capacity, force and pressure. These applications generally require some knowledge of air density. This paper offers the metrologist, bench scientist and laboratory technician a practical guide to the determination of air density and the associated uncertainty estimate. The measurement process usually begins with a problem definition and then an error analysis. Many problems are repetitive and set forth in paper standards. Often the metrologist or experimenter is faced with a measurement problem that will be performed a very limited number of times and for which he has little experience.
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Document ID:
D356CA00
NIST Random Profile Roughness Specimens And Standard Bullets
Author(s): J. Song, T. Vorburger, R. Clary, m. Mcglauflin, E. Whitenton, C. Evans
Abstract/Introduction:
Based on the numerical controlled (NC) diamond turning process used previously for manufacturing random profile roughness specimens, two prototype standard bullets were developed at the National Institute of Standards and Technology (NIST). These standard bullets are intended for use in crime laboratories as check standards to help verify that the computerized optical-imaging equipment in those laboratories is operating properly. There is also a potential use of these standard bullets for enabling nationwide and worldwide ballistics measurement traceability and unification. Testing results showed that these standard bullets have identical signature marks and minimal geometrical non-uniformities such as pits, damage, etc. The digitized bullet signature is stored in a computer and can be used for reproducing the same bullet signature anytime. In this paper, the design, manufacturing technique, testing results, and potential use are discussed.
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Document ID:
F3E149AB
Asymptotic Extreme Value Applied To Shape Measurements
Author(s): Michael Sharp
Abstract/Introduction:
A television picture tube is made from two large pieces of glass. The front faceplate is referred to as the panel, the back part is the funnel. Two major internal parts are the shadow mask - a perforated metal sheet located just behind the inside surface of the panel, and the electron gun, located at the rearmost part of the funnel. One major dimensional measurement issue is the inside curvature, or contour, of the panel. This obviously affects the geometry of the displayed image. Less apparent but perhaps more important, the spacing between the shadow mask and the inside surface must be held within tight dimensions. This is a major quality issue. The brightness of the image and the purity of the displayed colors are critically dependent on this spacing, especially at the corners of the image.
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Document ID:
FFE239FF
Practical Problems With Correlated Measurements
Author(s): Philip Stein
Abstract/Introduction:
Many, if not most industrial measurements are made for the purpose of inspection, that is acceptance or rejection of product. When a product is exposed to a battery (2) of such tests, failure of any one test will fail the product. If those measurements are correlated, though, this common procedure will yield the wrong answer. This could very easily become expensive as acceptable product is rejected due to incorrect math. Mike Sharps paper, one of the others in this session, refers to an inspection system for TV picture tube faceplates. In this application, as with many others, a number of measurements of product quality is made, often a large number, and the unit of product is rejected (declared to be a defective) if any of those measurements are outside specified limits or tolerances. This is such a common practice as to be invisible, like air.
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Document ID:
CEA899B6
A Method To Quantify Uncertainty Due To Bias In Chemical Analyses
Author(s): Raghu Kacker
Abstract/Introduction:
A widely accepted approach to assure that the certified property of a chemical reference material is independent of the method of analysis is to analyze by two or more judiciously chosen methods. The statistical problem then is to determine the consensus value of the measurand and the uncertainty concerning the measurand. This paper describes a new approach to determine the consensus value and the uncertainty. The proposed approach is based on the Guide to the Expression of Uncertainty in Measurement. This approach is not only better than the earlier approaches but it saves cost and time as well.
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Document ID:
ED020A11
Is Accreditation Enough? How To Ensure Calibration Providers Really Do Meet The ISO9000 Calibration Requirements
Author(s): Paul Roberts
Abstract/Introduction:
At first sight it appears that obtaining calibration from accredited laboratories will guarantee all of the ISO9000 paragraph 4.11 calibration requirements are met. However, there are a number of issues such as the extent of calibration, calibration environment, and the calibration uncertainty which must be considered in relation to the users application requirements to ensure the ISO9000 requirements really are fully met. This paper explores these and other issues involved providing guidance enabling equipment users make the best choice of calibration provider to meet both their technical and commercial needs, to fully comply with ISO9000 requirements, and to ease the task of demonstrating their compliance during an ISO9000 assessment. The discussion will be of interest to all fields of calibration.
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Document ID:
5D9563F1
Calibration Data Management: Meeting The Reporting Requirements Of ISO/IEC Fdis 17025
Author(s): Nicholas Mason
Abstract/Introduction:
ISO Guide 25, General Requirements for the Competence of Testing and Calibration Laboratories requires the collection and reporting of various information about instruments calibrated by a metrology laboratory. Many Metrology Laboratories are using personal computers (PCs) connected to increase productivity and collect and report information required by the standards. This paper discuses PC based tools to assist in the collection and reporting calibration information required by ISO17025 such as estimates of measurement uncertainty, calibration certificates, and calibration reports. Shown are examples using commercial Calibration and Asset Management software.
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Document ID:
1426630E
Accreditation, Automation, And Answers. 3 As As It Applies To The Calibration Lab
Author(s): Tim Stark
Abstract/Introduction:
This paper presents experiences in automation and the calibration lab. Hardware, software, and most importantly, the measurement process will be examined as it relates to the systems implemented by the calibration lab. Techniques in the adaptation of paper procedures to automated processes will be presented as well as consideration of the impact that the measurement process and measurement uncertainty can add to this procedure. With a little thought, some careful analysis, and the proper attitudes, automation can enhance the capabilities of any lab and the implementation challenges can be overcome with the minimum of headaches.
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Document ID:
9097C171
A Novel Artifact For Testing Large Coordinate Measuring Machines
Author(s): S.D. Phillips, D. Sawyer, B. Borchardt, D. Ward, D.E. Beutel
Abstract/Introduction:
We present a high accuracy artifact useful for the evaluation of large CMMs. This artifact can be physically probed by the CMM in contrast to conventional techniques that use purely optical methods such as laser interferometers. The system can be used over large distances, e.g. over four meters, with an uncertainty of less than one part per million. The artifact is relatively inexpensive, robust for use in reasonable industrial environments, and significantly reduces testing time over traditional step gauge measurements.
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Document ID:
2C958603
Two-Dimensional Calibration Artifact And Measurement Methodology
Author(s): R. m. Silver, T. Doiron, W. Penzes m. Takac, S. Rathjen, E. Kornegay, S. Fox
Abstract/Introduction:
In this paper we describe our design and the manufacturing of a two-dimensional grid artifact of chrome on quartz on a 150 mm x 150 mm x 6.35 mm plate. The design has been agreed upon by a number of Semiconductor Equipment Manufacturers International (SEMI) participants working on a two-dimensional grids calibration task force within the Microlithography committee of SEMI. We present the measurement procedures and describe the algorithms used in the measurement process. We have procured a prototype artifact which is expected to be developed into a National Institute of Standards and Technology (NIST) distributed standard reference material once the final design has been agreed upon. We will present measurements made at leading industrial sites and develop a traceability chain based on these measurements in combination with NIST based measurements. The artifact has been measured on the NIST linescale interferometer as well as other NIST metrology tools. We will also present the status of the comparisons between these measurements and those performed by the industrial collaborators.
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Document ID:
EA268AC1
Self-Calibration And Error Compensation Using Reference Position Markers
Author(s): Huanyu Zou
Abstract/Introduction:
In this paper, reference position markers are proposed for self-calibration and error compensation. Self-calibration of x-y motion guides is discussed with a focus on the orthogonality calibration. An algorithm is developed using a closure method and reference position markers. The calibration uncertainty is estimated. Self-calibration of Abbe error is discussed: two sets of measurements made at different Abbe offsets combined with the use of reference position markers are proposed to develop an error map for Abbe error compensation. The limitation of pre-processed error compensation is also discussed.
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Document ID:
4EE01BEF
A Comparison Of Error Propagations For Mass And Conventional Mass
Author(s): Frank E. Jones, Randall m. Schoonover
Abstract/Introduction:
Conventional Value of the Result of Weighing in Air The conventional value of the result of weighing in air, mC, is defined 1,2 as: mC m 1 - o/(20oC)/ 1 - o/ref, (1) where m is the mass of an object, o 1.2 kg/m3 is the reference value of the density of air, ref 8000 kg/m3 is the reference value for the density of the object, and (20oC) is the density of the object at the reference temperature 20oC.
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Document ID:
151477D7
Theory And Traceability Of The Wavetek 9100 Active Impedance Function
Author(s): Peter Crisp
Abstract/Introduction:
Modern multi-function calibrators have to support a very wide range of calibration products ranging from simple analogue meters to complex multi-function DMMs. The range and functionality are so diverse that it is becoming increasingly difficult to support the cost-effective calibration of these instruments using simple calibration standards. To be able to address the workload effectively, the Wavetek 9000 and 9100 Multi-product calibrators feature active impedances to source the resistance and capacitance functions. Active impedance offers several advantages over conventional passive standards, these are wider range, variable output, programmability and the ability to remove the effects of connecting lead impedances. The latter is particularly important as much of the UUT workload are two terminal devices. This paper examines the theory of operation of the active impedance function, its traceability methods and uncertainty considerations.
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Document ID:
71FB539E
A Container For Electrical Noise: Ultraguard Theory And Practice
Author(s): Karl Anderson
Abstract/Introduction:
A theory for active containment of electrical noise within a region is presented. A technique called the ultraguard, based on this theory, is presented and experimentally verified. The ultraguard is demonstrated to prohibit undesired charge flow in a signal-carrying conductor from arising due to noise signals that develop between a regions conductive boundary and a signal-carrying conductor passing through the region. The technique is experimentally demonstrated to operate despite distributed and randomly varying impedance between the signal conductor and the conductive region boundary. The region can be volumetric (i.e. within the shield of a signal cable or within an enclosure surrounding a system or subsystem) semivolumetric (i.e. within a partially-open container) or planar (i.e. within a conductive boundary such as a guard ring or channel on a printed circuit board surface).
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Document ID:
CC5ADACF
NIST Artifact Standards For Fiber Optic Metrology
Author(s): Paul A. Williams
Abstract/Introduction:
The primary means of transferring fiber optic calibration metrology at the National Institute of Standards and Technology is through artifact standards called Standard Reference Materials (SRM). NIST currently provides SRMs for fiber geometry (fiber cladding diameter and coating diameter, ferrule inner and outer diameter), and fiber propagation characteristics (mode-field diameter and chromatic dispersion). Also soon to be available are SRMs for polarization-mode dispersion and polarization-dependent loss in fibers. This paper will discuss the characteristics, applications and impact of these artifact standards.
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Document ID:
0FE24954
Optical Fiber Power Measurements
Author(s): Igor Vayshenker, Xiaoyu Li, David J. Livigni, Thomas R. Scott
Abstract/Introduction:
We describe NIST measurement services for the calibration of optical fiber power meters. To augment the absolute power measurements NIST provides nonlinearity, spectral responsivity, and uniformity measurements. We explain the measurement standards, systems, methods, and uncertainties related to the NIST calibration services for optical fiber power meter. Fiber connector issues are briefly described. Since optical fiber power meters (OFPMs) are a very common type of optical test equipment, NIST has developed and implemented measurement services to help characterize these instruments.1 These measurement services consist of absolute power calibrations using either parallel-beam or optical fiber/connector configurations. In addition, NIST provides measurements of nonlinearity, spectral responsivity (based both on tunable lasers and white-light sources), and uniformity. Calibrations are available at the three principal wavelength regions used by the optical fiber telecommunications industry, 850, 1300, and 1550 nm. Other optical power meter users (e.g., compact-disc player manufacturers and users of erbium-doped fiber amplifiers) are additionally interested in 670, 780, and 980 nm. We have also incorporated these wavelengths into our absolute power calibration program as well.
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Document ID:
EAD0338B