The Future of Commercial and Military Measurements, Calibrations, and Standards
Remarks of Robert Hebner, Acting Deputy Director, National Institute of Standards and Technology, at Ninth Air Force Worldwide Precision Measurement Equipment Laboratory Workshop, on June 29, 1998, at Denison University, Granville, Ohio.
Good morning. I'm pleased to have this opportunity to share with you some thoughts on the importance of maintaining and further developing metrology and calibration capabilities, including the expertise that underlies these essential capabilities. Of course, this entails some speculating on the future of measurement and calibration services. At the National Institute of Standards and Technology, we need to concern ourselves with this evolution because it is our responsibility to continue to meet the needs of the users of the national and international metrology systems in a rapidly changing world. And the military is a large and very important user and developer of metrology and calibration services.
I would like to preface this speculation with an anecdote that highlights the pitfalls inherent in attempting to anticipate the direction and impact of technological changes. One of the first management decisions to which I contributed was the planning to upgrade NIST’s capability to calibrate watt-hour meters. On the side of every home and business, these meters are used to determine one's electric bill.
At that time, nearly all of the meters were electromechanical, but a few prototype electronic meters had been submitted for calibration. The question we had to address was, "Should our upgraded calibration system be expanded to accommodate electronic meters conveniently?"
In search of an answer, I talked to experts in the field. They told me that the question showed that I was young, inexperienced, and overly enamored with new technology. They explained that the question boiled down to simple economics: The electromechanical meter was more accurate than anyone needed, very reliable, and inexpensive.
Electronic meters, these experts said, were unreliable, nearly ten times more expensive, and only potentially more accurate. They'd never be more than a small percentage of our calibration workload.
In the first year of our new service, about 80% of the meters that we calibrated were electronic. Not many years later, we started serious consideration of eliminating all routine calibrations of electromechanical meters and only calibrating electronic meters.
I could also give you the good, but ultimately flawed, arguments that were used over the years to dismiss computers as unimportant to metrology and to reject the notion that accurate measurements could be automated. But I think that I've made clear the folly of predicting with certainty what will or will not happen.
So with a healthy respect for the unpredictability of change and progress, let's explore the nature of NIST's current and future interaction with the Defense Department’s measurement enterprise. To do this, we must contemplate some of the technological advance that is occurring in both the commercial and military arenas—but not with the naive expectation that we can predict the details of what will happen. A better and more realistic goal is to anticipate the nature of the changes likely to occur. And of one thing we all can be certain: the need for advanced metrology techniques by the nation’s military—the most technology intensive of American enterprises—can only grow.
NIST in Context
For nearly all of its 97-year existence, NIST has provided hard-to-find measurement assistance to the Armed Forces. The primary mission of NIST, however, is to promote economic growth by working with industry to develop and apply technology, measurements, and standards. Note that the focus of this mission statement is on commercial industry--that is where our primary responsibility lies. Today, NIST has four major programs that attend to the infrastructural technology needs of U.S. industry.
These are the:
Although NIST concentrates on the technology needs of the commercial sector, we do interact closely with the Department of Defense to solve important measurement problems that impact the performance of defense systems. This work spans most of NIST’s seven Measurement and Standards Laboratories. I’ll give a few examples in a moment. But, first, I would like to discuss the basic operation of the national and international measurement systems, along with NIST’s contributions to the health and performance of these systems.
The international system of units—known as the SI--provides the basic definitions for essential measurement units. The meter, for example, is defined as a fixed number of wavelengths of the light emitted by a specific atomic transition. To determine how long a meter is, one must establish a laboratory containing the apparatus necessary to emit the light and measure it. Of course, you don't only need to measure a meter. You may need one billionth of a meter to measure a property of a transistor and thousands of meters to survey your country. Thus, you'll also have to develop methods to scale the measurement accurately over these tremendous spans.
You also need to realize and scale all of the other six base units so that one can accurately measure electricity, chemical concentration, temperature, pressure, light, weight, and the thousands of other quantities that are required by commerce and regulation. If every public and private laboratory were required to do this, the economic cost would be enormous, and it would be terribly inefficient. In practice, however, most organizations do not require the world’s most accurate measurement. Or, to put the situation another way, if the national measurement institute realizes the definitions of the various basic and derived quantities with world class accuracy, it is unlikely that any other laboratory in the country will need to duplicate the effort.
In the United States, NIST attempts to realize all of the basic units and important derived units with world class accuracy. Other U.S. laboratories and companies need not realize the basic definition themselves, since nearly all commercial needs can be met with lower levels of measurement accuracy. Instead, they can compare with NIST. If their accuracy requirements are even more modest, they can compare with a laboratory that compared with NIST. This is the concept of traceability.
Traceability is generally accomplished through a calibration or through a reference material accompanied by a piece of paper that documents the measurement results. This concept of traceability works well within a country and, depending on the application, a large number of ways have been established to assure that the needed accuracy is achieved.
Among countries, however, the situation is somewhat different. If the countries have laboratories that realize the basic units from the fundamental definitions, with well documented levels of accuracy, then--in principle--they are comparing with fixed values. There would be no need to compare with each other. As a quality control mechanism, however, national measurement institutes do compare measurements. They do this primarily to assure themselves and others that they have identified all the errors in their laboratories properly.
Historically, these key comparisons have been done as various laboratories believed necessary. Recently, the institutes have come together and regularized the key comparison process. Key comparisons are typically documented by a published article in an archival journal.
NIST's unique responsibility for ensuring that U.S. measurements conform with international standards is a matter of great importance to the nation’s military. Comparability of measurements helps to guarantee that U.S. weapons and communications systems achieve necessary levels of compatibility with the equipment of NATO allies and that of other countries participating in joint operations. Such measurements include frequency and power levels of radio communications systems and IFF—Identification Friend or Foe—systems; time scale for synchronization of operations, advanced telecommunications, and navigation; and dimensions of weapons, munitions, and interchangeable parts.
Now that we have taken a look at how NIST fits into the big picture of national and international measurement systems, let’s talk about some specific metrology projects that NIST has undertaken with the military. Several are drawn from examples that the Calibration Coordinaton Group has singled out because of their sizable impact on the Armed Services.
Consider NIST-developed techniques for precision near-field antenna scanning. During Operation Desert Storm, NIST scientists used their techniques to diagnose the causes of failures in a phased-array antenna that was part of a critical communications link between the United States and the theater of operations. Instead of being sent to the factory for conventional repairs, which would have taken months, the advanced antenna was rapidly diagnosed, repaired, and used throughout the conflict. NIST’s precision antenna-scanning methods have since been adopted by the Defense Department.
Then there’s the issue of shrinking dimensional tolerances—a trend that applies even to the largest of military systems. For reasons of improved quality and performance, large structures and systems are being designed to meet increasingly tighter tolerances. Missing the mark can be costly.
The need for frame-straightening, for example, adds $3.4 million to the cost of each Arleigh Burke class destroyer. To improve the fit of parts on such large structures, manufacturers are using a 3D positional measurement instrument invented at NIST in the 1980s--the laser tracker. Capable of performing rapid, automated measurements over very large volumes with high accuracy, the laser tracker is now commercially available. In the aerospace industry, the instrument is used to do in-process measurements and to correct machine-tool path errors in real time. In addition, aerospace firms use laser trackers to make digital parts from full-scale models, saving $4.5 million a year in reduced maintenance costs for each master model. Industry and the military are now looking to NIST for technical leadership in developing standards for estimating uncertainty, testing, and evaluating the performance of laser trackers.
Earlier NIST work funded by the Air Force has resulted in tools that improve the accuracy and reliability of measurements made with CMMs, or coordinate measuring machines. When the Air Force learned that more than half of its CMMs—key pieces of inspection equipment—failed their annual recertification checks for accuracy, it was immediately recognized that, as a consequence of measurement errors, inspectors may have been accepting bad parts and rejecting good ones.
The Air Force turned to NIST for a solution, which then discovered similar problems at commercial manufacturing plants. Laboratory researchers developed an easy-to-use tool for quickly assessing CMM performance, making daily, rather than annual, evaluations practical. The NIST innovation is becoming an important quality assurance tool for a growing number of manufacturers inside and outside the defense industry.
In the area of electrical measurements, NIST’s success in developing the world’s most accurate voltage reference source, known as the Josephson voltage standard, also is paying national security dividends. The Army, for example, now has its own Josephson standard. The primary standard provides the Army with an added level of assurance that precision weaponry and other advanced instrumentation are calibrated accurately. Increasing the accuracy of calibration prevents measurement uncertainties that can result in missed targets, surveillance failures, and inaccurate data transmissions. The Army plans to install a version of the standard directly into some of its equipment, leading to further performance gains and estimated annual savings totaling $3 million.
By the way, we are now working to develop a new generation of programmable voltage standards that can move rapidly to any specified output voltage. Ultimately, the new standards should be fast enough to synthesize ac waveforms.
I could go on and cite other examples of how collaborations with the CCG or with a specific branch of the military have helped to advance the field of metrology, while contributing to the effectiveness of national security systems. Although only a sampling, these projects and programs underscore the importance and impact--in terms of dollars, lives, and time saved--that metrology capabilities have in the procurement, development, fabrication, operation, and maintenance of military systems.
In some ways, however, the past, may not necessarily be prologue. We face a future with a mountain of defense-driven measurement needs on its horizon. And in the foreground, there are rather substantial foothills of already documented voids in measurement capabilities.
Changes in the Military
Today, nearly all aspects of the life cycle of military systems are changing. Recent acquisition reforms are reshaping procurement, development, fabrication, operation/deployment, and maintenance. There is a strong emphasis on reducing the cost of ownership. Budget pressures and changes in Defense Department policies are increasing the military’s reliance on commercial off-the-shelf (COTS) components and systems.
In June 1994, then Secretary of Defense William Perry announced "A New Way of Doing Business," which specifically prohibited the use of military specifications and standards without a waiver by the Milestone Decision Authority. Additionally, the Secretary required use of performance-oriented requirements in system specifications and statements of work. Motivations were rapid insertion of new technology, cost savings, and shorter development cycles. DoD was directed to increase access to commercial state-of-the art technology and update its business processes.
Instead of creating its own specifications for every kind of supply, the DoD is now tasked with facilitating integrated, dual-use commercial and military development and manufacturing.
At the same time, the technological needs of the military are changing:
Yet, the overall strategy to maintain defense superiority remains the same: Technological superiority. This will require leveraging rapidly advancing technologies in many areas. It will require exploiting the best that the commercial sector has to offer. It also will require identifying--and addressing--technology needs that are unique to the Air Force, Army, or Navy—needs that will fall outside the scope of commercial R&D efforts.
It is obvious that if U.S. military systems are assembled solely from commercially available offerings, then potential adversaries could easily counter—and, perhaps, surpass--our capabilities. Next generation weapons systems must employ advanced technologies not easily available to adversaries. Achieving the optimal balance between commercial technology and security-driven technology development will be a continuing challenge.
Needed: A 21st Century Measurement Infrastructure
To support cutting edge technology, the military needs cutting edge metrology capabilities. If you can't measure it, you can't make it. Nor can you efficiently assemble the myriad contractor- and subcontractor-supplied pieces. And you can’t achieve the interoperability and connectivity that are so vitally important to command, control, and communication capabilities.
We believe a substantial portion of military metrology expertise must be provided from within the network of military laboratories and contractors. Efforts focused on private sector measurement needs will not push certain edges of the technology envelope that lead to key elements of tomorrow’s military systems. Furthermore, greater reliance on performance-based specifications (as opposed to build-to-print) introduces the need for new and different measurement and test capabilities to verify that specifications have been met.
The metrology effort supporting the MILSTAR system provides a good example of why the military must sometimes drive the advance of the nation’s measurement infrastructure. The MILSTAR work performed by NIST and supported by the CCG pushed NIST capabilities into frequency ranges that we weren’t considering at the time. Commercial entities eventually developed a need for measurement capabilities in these frequency ranges, but much later.
Of course, in some areas, commercial needs will drive progress in measurement capabilities, and the military also will benefit. A variety of the areas that NIST works in will be of interest and value to the military. This is the work that the taxpayers support through our base budget. But there is also a very significant amount of DoD work that lies outside our mission to assist commercial industry. These needs must be met by military and contractor capability—either that or suffer the cost overruns, delays, and other negative consequences of the lack of measurement and test capability when it is needed.
Unfortunately, support for metrology capabilities within the military has been declining, and a backlog of measurement needs is building. This trend should be reversed to meet the needs of a technology-based defensive force. As in some companies, there is the temptation to treat measurement functions as a management activity, rather than to view measurement capabilities as integral to an organization’s technological competitiveness—as sources of strategic advantage.
The Changing Face of Metrology
Having presented a case for increasing support for metrology capabilities in the military, I would like to take this opportunity to say that from my perspective, the way measurement capabilities have been developed and implemented in the past is not going to work for the advanced systems of the future. I believe this is true for both the commercial and the military sectors.
In the commercial sector, we see the growth of electronic commerce. Virtually ever aspect of business operations is going "on line" or, at least, is moving in that direction. In concert, there is growing emphasis on outsourcing, reduced time to market, globally distributed design and manufacturing, supply chain optimization, and so on. The defense sector is experiencing the same pressures.
And so is NIST. We need to do our job faster, cheaper, and better. In a sense, we also need to make measurements "smaller"—to stay ahead of trend towards miniaturization and shrinking tolerances and to increase accuracy.
Consider the chain of calibrations and measurement traceability that I mentioned earlier. If NIST increases the accuracy of its measurements, accuracy can be improved at every link in the chain—calibration laboratories, industrial labs, factories, and all the way down to finished product. Improvements in accuracy deliver benefits that radiate—usually invisibly—through many sectors of the economy and society.
Clearly, NIST must continue to work to push the accuracy of all its measurments on to the next decimal point. We are doing that. We also are exploring ways to shorten the measurement chain so that there are fewer accuracy-reducing steps in the transfer of calibrations and measurement standards. Intrinsic standards are one approach that we are pursuing. The Josephson voltage standard is an example.
The aim here is to enlist nature’s own devices to produce measurements with the highest-order accuracy. Such standards are derived directly from unvarying natural constants. Our ultimate goal is to develop intrinsic standards that can be provided directly to customers with no, or very little, deterioration in accuracy. Obviously, the cost of such standards will figure importantly in the scenario that we envision.
Nonetheless, intrinsic standards offer one long-term approach to meeting the needs of the new military. They are a means to distributing measurement services, to pushing capabilities out further to the point of use--even down to the individual pilot, soldier, or sailor.
Information Technology May Change Everything
Advances in information technology present a whole new set of exciting possibilities. Information technology has the potential to transform the metrology business. The changes may be profound, resulting in entirely new approaches to delivering measurement and calibration services.
We have begun a major program to examine these issues, called the National Advanced Manufacturing Testbed, or NAMT. The NAMT is a distributed testbed built on a state-of-the-art, high-speed computing and communications infrastructure that has been developed to support collaborative research between NIST, industry, academia and other government agencies. The NAMT currently hosts 16 projects that are using high-bandwidth ATM networking technology to connect outside industry, university, and government partners with NIST researchers and equipment.
Topics range from on-line calibrations of flow meters to methods for remote fabrication of atom-based dimensional standards for semiconductor manufacturing. Partners are electronically connected through the testbed's common infrastructure. Moreover, collections of resources and personnel can be easily configured - and reconfigured - in response to changing research needs and objectives. The virtual technology elements of the testbed support research on applications of simulation and modeling methods that are essential to rapid prototyping and fast fabrication, among a host of other key capabilities.
These are the kinds of capabilities that the military will require. They will make measurement expertise available where it is need, when it is needed. Remote calibration, testing, repair, diagnostics, and maintenance will improve the performance and effectiveness of equipment and operations.
We can already see the shape of things to come. Telemedicine capabilities are being developed that allow a soldier and his local equipment to channel remote medical expertise to wounded comrades on the battlefield. In the semiconductor industry, an equipment manufacturer is offering a package of remote assistance tools that puts its experts on call at customer sites—but in a virtual way. A helmet donned by a service technician is equipped with a video camera, two eyepiece displays, a microphone, and a earphone. Remotely located experts can size up the situation, consult with on-site staff, and then troubleshoot a problem, providing a rapid response to minimize—or even eliminate—down time.
I would like to conclude by emphasizing three points that summarize my remarks:
As a final thought, metrologists are justifiably proud of their reverence for historical data and consistent practice. These underpin the confidence the world has in its measurement system. At the same time, if we do not embrace new technology, then we risk being made irrelevant by it. The challenge is to embrace both our history and appropriate new technology to make the 21st century measurement systems--commercial and military--significantly better than today's.