The National Coordination Office for Networking and Information Technology Research and Development wrestles with the form and substance of future distributed control systems. And Wayne considers Metcalf's law, the use of evanescent waves to power wireless sensors, and the California Energy Commission's efforts to cultivate energy-efficient technologies.
Beyond SCADA
What will distributed control systems look like in twenty years? The National Coordination Office for Networking and Information Technology Research and Development (NITRD) held its workshop—led by UC Berkeley's Shankar Sastry, with help from Helen Gill of the National Science Foundation and representatives of several other agencies—in Pittsburgh on November 8-9 to begin to answer that question. The NITRD has been looking at "high confidence" software and systems for the U.S.'s post 9/11 critical infrastructure. NITRD is composed of a group of government agencies that includes the Department of Energy, National Institute of Standards and Technology, National Science Foundation, and National Security Agency. The goal of the workshop was to help these agencies create a suitable research agenda for future networked embedded control for cyber physical systems. My goal was to show that wireless systems could play a role in such high-confidence systems.
Throughout the proceedings, I emphasized the need for analytical performance metrics and critical definitions. To do this, I started with the concept of high confidence.
Since the incident at Three Mile Island, when an operator took control because he did not trust the automatic systems, many recognize the importance of operator confidence. As I thought about how wireless will play in these high-confidence systems, I concluded, once again, that we need to include real-time performance metrics that allow an operator to determine the status of the sensing and control networks with sufficient analytical rigor to ensure the necessary confidence.
The term I introduced for this in an earlier Sensors Wireless Networking Newsletter was fragility. Fragility is a measure of confidence in a system that is a function of the difference between expected performance and actual performance. Expected performance can be based on analytical models or past performance.
The solicitation that will be coming out of this workshop will undoubtedly include something about analytical measures associated with performance. The idea of using commercial networks to control distributed resources still sounds scary to me, but my guess is that it's coming.
Metcalf's Law
The November issue of IEEE Spectrum has an interesting discussion of Metcalf's law, which asserts that the value of any network is proportional to n2, where n is the number of nodes on the network. Many folks dealing with industrial networks understand that a single node can have more value than the rest of the network combined. The latest thinking is that the value of a network is more like n log(n). This is likely closer to the value of the industrial networks that we see, and the wireless networks in particular.
Evanescent Waves for Powering Wireless Sensors
A new way to think about power harvesting is highlighted on the IEEE Spectrum Web site. Here MIT research shows that a new phenomenon called evanescent waves could supply up to tens of watts of power at efficiencies of 50% over a distance of several meters. Now that's something to think about!
California Energy Commission's Public Interest Energy Research
The CEC sponsors a program intended to bring energy-efficient R&D to the marketplace. The commission sponsors $62 million for energy efficiency R&D every year. I have participated in their workshops and have been impressed with their focus on deployment and impact. I continue to believe that a good partnership could result in a winning proposal to bring wireless technologies to some high-energy consuming industries in California. If someone would take a leadership role and put together a vision and case, I'm certain we could bring some technology suppliers to the table.
That's it for this month. See you next time.
—Wayne
