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App by app and tool by tool, scientists are studying whether digital health interventions work, with mixed results Photo: iStockphoto

As digital health continues to explode on smartphones worldwide, researchers are digging in, trying to figure out which of the new offerings actually work. These scientists aim to determine, using top notch clinical trials, the effectiveness of medical apps, telemedicine and other kinds of digital therapeutics and diagnostics.

It’s a big task. The pace at which software developers are commercializing digital health tools surely exceeds the pace at which scientists can study them. The good news: Unlike traditional medicine, there’s no shortage of data in digital medicine.

Here, we give you three studies, all published this month, that illustrate the different ways scientists are putting digital health through the clinical trial wringer. The conclusions show just how messy and nuanced digital health research can get. 

Photo: Headspace The Headspace App

1. Meditation app no better than a sham app at improving critical thinking

After being passed down for thousands of years, the teaching of mindfulness meditation by live human instructors is starting to be replaced by digital apps.

Proponents say the practice of meditation, which involves bringing one’s focus to the present moment, can reduce stress, increase attention, and even improve cognitive function. But the latter of those claims are backed by very little evidence, says Chris Noone, a psychology researcher at the National University of Ireland, Galway. 

Noone wanted to find out, with a rigorous study, whether the claims of cognitive benefits are true. The best way to do that, he felt, was to study people who practice mindfulness using an app.  

“A pps are the most popular way people are learning mindfulness meditation, ” he said in an interview with IEEE Spectrum. Plus, the digital aspects of apps offer  experimental controls, such as being able to double blind the study and standardize the instruction—something that can’t be done with live instruction.

Noone chose the popular meditation app Headspace, which offers specific mindfulness meditation instruction, and boasts millions of users in more than 190 countries. He pitted it against the same app with fake meditation instruction developed for research purposes, which  told users to simply close their eyes and breathe, says Noone.

Over 70 study participants were given a series of tests and questionnaires that score various cognitive functions such as  critical thinking, open-minded thinking and memory. Then for six weeks, half of the participants used Headspace and the other half used the sham app . 

After participants completed 30 meditation sessions, they took the cognitive tests again. Those who had used Headspace improved their test scores about the same amount as those who had used the sham, Noone and his collaborator Michael Hogan found. They concluded that there is no evidence that engaging in mindfulness meditation improves critical thinking performance. 

The participants “probably just got better at taking the test,” says Noone. The study was published 5 April in the journal BMC Psychology.

Photo: Medisafe An Apple watch with Medisafe reminders

2. Mobile app helps patients remember to take their blood pressure medication, but doesn’t improve their blood pressure

We aren’t very good at consistently taking our medication. That’s particularly true for people who must manage chronic conditions with drugs over long periods of time. 

Lots of apps are being developed to help people adhere to their drug regimens. There are over 100 such apps for hypertension, or high blood pressure, alone. The question is: Do these apps work? 

At least one does—a little bit—according to a study published 16 April in JAMA Internal Medicine. The authors asked more than 200 people to use smartphone software called Medication Adherence Improvement Support App for Engagement-Blood Pressure, or MedISAFE-BP. The app aims to help people with hypertension remember to take the meds, and includes reminder alerts, adherence reports and optional peer support.

After 12 weeks, the researchers saw a “small” increase in medication adherence among people using the app, compared with no change in a control group. Despite taking their medication more consistently, there was no improvement in systolic blood pressure compared with the control group, possibly due to fluctuations in home blood pressure readings, the authors conclude.

The study is the first to assess a hypertension medication adherence app as a stand-alone intervention in real-life settings, according to the report. Other smartphone adherence tools   have been studied in clinic-based settings, or used to improve patient-doctor communication. 

3. Telemedicine tool is as effective as an in-person exam at diagnosing rare cause of blindness in babies.

For more than a decade researchers have been studying whether it’s possible to accurately diagnose diseases of the retina using only a photograph of the eye. If an image is just as good as an in-person exam, the thinking goes, patients can seek opinion from the most highly skilled specialists without having to travel long distances. 

The conclusion, after dozens of these studies, is yes: Images—the telemedicine version of the eye exam—are just as good as the live thing.  

But virtually all of those past studies make the same troublesome assumption: that the in-person eye exam is the gold standard. “They assume that the exam done by an expert in an office gives you the correct answer,” Michael Chiang, a professor of ophthalmology and medical informatics at Oregon Health and Science University in Portland, said in an interview with IEEE  Spectrum. “But when you look at the photograph of the eye, there is photographic evidence that the clinical examiner made a mistake. It’s been a bit frustrating for me.”

Chiang wanted to see how accurate telemedicine exams are when compared to an impartial gold standard. So he and his team created a new reference standard based on a majority vote system from a three-person panel of experts. “It was extremely painstaking to come up with that reference standard. And it’s not perfect,” Chiang says. “Be we thought it was better than anything else out there that we’re aware of.”

Then Chiang and his team ran a study that looked at the accuracy of telemedicine diagnoses and live exams independently. Instead of comparing them to each other, they compared them with the new reference standard. 

They focused on infants with retinopathy of prematurity, which is the leading cause of blindness in preemie babies. The disease can be diagnosed by examining the patterns of certain structures in the eye, either by looking through a magnifying device that shines a light into the baby’s dilated eye, or by studying images taken by a wide-angle ophthalmic camera

The result: Telemedicine exams were just as good as live exams in the study. But there’s one caveat: In cases where there was a minor level of disease—usually on the periphery of the eye—the live exam more often caught it. Chiang hypothesizes that either the cameras did not perfectly capture structures at the periphery, or that examiners saw something that wasn’t actually there.

It’s not the most satisfying result. “Telemedicine works pretty well for diagnosing eye disease, but neither a real eye exam nor telemedicine is perfect,” says Chiang. 

The advantage of telemedicine, however, is that it gives people a way to connect with the right experts. Patients can have their images sent to certain specialists, rather than being stuck with the examiner who happens to work nearby. “W ho does your exam matters more than what method they use,” Chiang says.

His study was published 5 April in the journal JAMA Ophthalmology. 

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Thriving in today’s world means philosophical sacrifices Illustration: Chad Hagen
Illustration: Chad Hagen

From time to time I have seen Internet videos of seemingly impossible gymnastic performances. Sometimes the links to these videos have been accompanied by a comment by the poster to the effect of “I could do this if I wanted, but I choose not to.” This brings a little smile to my face, but I’ve been thinking lately that I’ve been telling myself something similar when I see some of today’s technical literature.

The scope of electrical engineering has been growing continuously through the years, but so too has the depth of complexity and required knowledge across this ever-larger landscape. There are many more highly trained engineers worldwide now than there were a few decades ago, so new applicable knowledge accumulates at a faster pace, while it seems that older, irrelevant knowledge leaves the field more slowly. There is more to know, and it is more demanding and complex.

I took a cursory look, for example, at the mathematics in information theory or the physics in quantum computing or in electronic and optical devices, and I said to myself, “I could do this if I wanted, but I choose not to.”

I remember when engineering seemed much simpler. As I write this, I’m noticing across the room the little blinking node on my Wi-Fi mesh network. Not so long ago AM/FM radios and TVs were the ubiquitous home electronics exploiting the electromagnetic spectrum. Those were the days when radios were just simple devices whose only standardization was the frequency band and a fairly simple modulation scheme. Take a look, though, at the specification for the IEEE 802.11ac family of Wi-Fi transceivers.

There are many, many pages of complicated minutiae needed to describe the protocols, controls, signal formats, and so forth. Then, if we dig down deeper, the math for multiuser MIMO (multiple-input, multiple-output) needs to be understood. The encryption is based on elliptic curve cryptography—try checking that out. Everywhere we look at increasing depth, the complication turns to turgid complexity. That is the world we live in now.

How is it that we can survive and indeed thrive in such a world? The obvious answers are specialization to narrow the field, and the layering of knowledge to reduce complexity to only that needed for a given purpose. In this latter pursuit we are aided by software that empowers the user while hiding the underlying complexity. I think that most engineers seldom will have the need, or the privilege, to examine the complex math and physics beneath so much of what we do. I’m reminded of the perhaps apocryphal tale of Richard Feynman’s advice on understanding quantum mechanics, when he said to just “shut up and calculate.”

So, am I kidding myself that I could do this stuff if I chose to? I hope not, but I can’t be sure. The problems are time and motivation. I have the engineer’s curiosity and I want to know everything, and it bothers me when I don’t truly know how something works. But there is limited time and so very, very much to know. Sadly, I have to choose, and the choices are influenced by motivation. There are things that I have to know, and things that it would be nice to know. Often, the former overwhelm the latter.

The way complexity is increasing, I imagine that in the future, computers will be writing papers for the IEEE societies’ Transactions, but those papers will be so complex that only other computers will be able to understand them. A lot of the fun will be gone.

This article appears in the May 2018 print issue as “Deep Complexities in EE.”

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Bradford W. Parkinson shepherded the first GPS constellation to launch, and pushed for civilian access Photo: Gregg Segal
Photo: Gregg Segal

As I drive through the vineyard-covered hills of San Luis Obispo, Calif., the tiny Global Positioning System receiver in my phone works with Google Maps to alert me to upcoming turns. The app reassures me that I’ll arrive at my destination on time, in spite of a short delay for construction.

How different this trip would have been in the pre-GPS era, when the obscured road sign at one intersection would likely have sent me off track. I have a weak sense of direction, and getting lost—or worrying about getting lost—was a stressful part of my life for a long time.

This GPS-guided journey is taking me to Bradford W. Parkinson, the person who made GPS technology—a tool we now take for granted—come together. Parkinson is being awarded the 2018 IEEE Medal of Honor for leading the development of GPS and pushing its early applications.

“Just don’t call me the inventor of GPS,” he says moments after we meet. “I was a chief advocate, the chief architect, and a developer, but I was not the inventor.”

How about “leader”? “Even that’s overblown. I surrounded myself with guys who would not fail.”

Brad Parkinson may be modest about his contributions, but it’s hard to dispute that he was the person who turned a pie-in-the-sky vision of navigating by satellite into a reality.

Parkinson’s preparation for his GPS role began early, with a passion for maps. The walls of Parkinson’s boyhood bedroom were covered with large maps of northern Minnesota’s Boundary Waters—lakes and streams he loved to explore by canoe. “It was easy to get lost,” he recalls. “You had to keep your wits about you.”

Then there was his summer job in 1957, just after graduation from the U.S. Naval Academy, as a surveyor on a large construction project.

His graduate education put down another stepping-stone. Sent to MIT in 1960 by the U.S. Air Force, which he’d joined rather than the Navy, he took several courses in inertial navigation. Charles Stark Draper was teaching them, and so it was an irresistible opportunity. That coursework led to a three-year post as chief analyst for inertial navigation systems testing at Holloman Air Force Base.

In 1964, he headed off to Stanford for Ph.D. studies. His thesis advisor was Benjamin Lange. “Ben wanted to put a free-rotor gyroscope in orbit to test the general theory of relativity,” Parkinson says.

Parkinson invented a sensor that could tell the position of the rotor relative to the desired axis. Using an algorithm he called hemispheric torquing, he could then apply a magnetic field to adjust the rotor’s position, sending it spinning along the desired axis without changing its overall position in space. Parkinson’s technology is still in use today in some highly accurate inertial navigation systems.

Photo: Gregg Segal GPS On Board: Brad Parkinson, with a model of the GPS IIF satellite, gazes across the farmland near his California home. He sometimes spots GPS-guided automated tractors at work in the fields.

As Parkinson’s knowledge of navigation and space systems grew, the seeds that became GPS were being planted by others. In 1960, the U.S. Navy began testing its Transit program, a satellite-based method of updating the inertial guidance systems used by submarines. Transit’s system worked with as few as four satellites (though the constellation typically included more) in low polar orbits. Along with a network of ground stations, the satellites allowed slow-moving vessels to determine their longitude and latitude a few times a day with an accuracy of about 100 meters.

Ivan Getting, president of the Aerospace Corp., didn’t think that was good enough. In 1962, he started campaigning for a three-dimensional satellite-positioning system that would be more accurate and always available. Getting told me some years ago that he promoted this vision to the presidential science advisor, the heads of the armed forces, and anyone else he thought could have influence, trying “to get the damn thing funded.”

Getting’s evangelism led to an Air Force–sponsored study of space-based navigation. The final report, by James Woodford and Hiroshi Nakamura, was published in 1966, although it remained classified until 1979. It laid out 12 main techniques, including the one that became GPS.

In 1972, Parkinson’s path and satellite navigation’s evolution collided. Parkinson had spent the previous year studying at the Naval War College, in Newport, R.I., and sailing whenever he could. Up next would likely be an assignment in the Pentagon.

Then he got a call from a colonel who was part of a group known as the Air Force’s inertial guidance mafia. “This wasn’t a black-hat organization,” Parkinson explains, “just people who had gone through the MIT inertial guidance course who looked out for each other.” The colonel recommended that if Parkinson wanted to build systems rather than just analyze them, he should join the Advanced Ballistic Reentry System (ABRES) program, in Los Angeles.

Parkinson, just promoted to colonel himself, took the advice and moved to Los Angeles. He’d been at ABRES a little over three months, working on advanced nose cones and other missile technology, when he was identified as a perfect fit to take over a satellite navigation program called 621B. Parkinson had the right qualifications, but he didn’t want the job.

“The consensus was that the program was going nowhere, that it was absolutely dead,” he says.

But it was a three-star general making the offer, Parkinson recalls, and you don’t say no to a general—usually. Parkinson said he’d take the job if he could be named program manager. Anything less, he said, would have been a downward move and wouldn’t have allowed him to control the program—“and the program was in deep trouble.”

The general refused. “So I said, ‘Then I don’t volunteer,’ ” Parkinson recalls. “He wasn’t used to brand-new colonels saying ‘No’ to him.”

Parkinson walked out of the office—but he had barely gotten through the door, he says, when the general called him back. Parkinson got his title and took over 621B in mid-1973.

The 621B program aimed to create a satellite-based navigation system that would work almost anywhere in the world. The team had already developed much of the plan and wanted to demonstrate it using four satellites—not an inexpensive proposition.

Parkinson began by going through every piece of the proposal with his engineers.

“We were a little worried when he first came on,” recalls Walter Melton, an engineer assigned to the project from the Aerospace Corp. “We heard that he was from the inertial mafia.” The engineers were concerned that Parkinson would be biased against satellite navigation, which was considered a competitor to inertial navigation. “But after the first several weeks it became clear he understood and was a supporter.”

In August 1973, Parkinson presented the proposal to the Defense Systems Acquisitions Review Council at the Pentagon. “I told all these generals and senior civilians sitting around a table what I was trying to do, and then they took a vote,” he recalls. The vote was “No.”

Malcolm Currie, then undersecretary of defense research and engineering, chaired that meeting. At the time, Currie was spending a lot of time near his home in the Los Angeles area, preparing to move his family to Washington, D.C. During one of Currie’s Los Angeles trips, Parkinson gave him a one-on-one tutorial on satellite navigation that took up most of an afternoon.

Parkinson now thinks that afternoon was the reason satellite navigation didn’t die after the “No” vote. Indeed, it made an ally of Currie, who quickly reminded Parkinson that the concept presented was merely one he had inherited, not developed himself.

Parkinson reported in an oral history that Currie told him, “Listen, you did a very, very nice job, but you and I know that this is not truly a joint program…. Go back, reconstitute it as a joint program, and bring it to me as quickly as you possibly can, and I am very, very certain that we are going to approve it.”

Parkinson and his engineers worked over Labor Day weekend to develop a new architecture for their satellite-navigation system. They met at the Pentagon rather than in L.A., he says, “because too many people associated with the program were entrenched in old ideas.” Gathering in offices that were vacant because of the holiday, Parkinson says, “We hammered out what we wanted to do, and we summarized it in seven pages.”

Photo: U.S. Air Force Talking Satellites: Brad Parkinson [center] discusses GPS navigation with the Aerospace Corp.’s Frank Butterfield [left] and the U.S. Navy’s Bill Huston in the mid-1970s.

Parkinson recalls that the “Lonely Halls” meeting, as it came to be known, led to several key changes: The system’s code-division-multiple-access (CDMA) radio signal was modified to include a civilian signal as well as the protected military signal; the orbits of the satellites were adjusted to reduce the number of satellites needed at the optimal altitude, considering the range of available launch vehicles; and the design embraced orbiting atomic clocks, which would free ground-based receivers from the need to keep precise time.

Parkinson says this third change was the most risky—atomic clocks that could handle space radiation did not yet exist. But he knew that Roger Easton at the Naval Research Laboratory was developing a space-qualified atomic clock as part of the Navy’s Timation satellite navigation program—and he bet that some version of that clock would be available for the demonstration satellites.

This decision turned out to be critical for the cheap, small GPS receivers that consumers use today. If instead we all had to carry around superaccurate clocks, the receivers would be vastly more expensive and as large as a stack of dictionaries, Parkinson says. They also would require periodic synchronization to maintain accuracy. They certainly wouldn’t have turned into a tiny package of electronics costing a fraction of a dollar, tucked inside every cellphone.

And Parkinson badly wanted consumers to use the new system. The mission of the project, in his view, was always twofold—extraordinary accuracy and affordability. He even hung a wooden plank above the entrance to the project’s offices in Los Angeles to reinforce the message: “The mission of this office is to drop five bombs in the same hole and to build a cheap set that navigates—and don’t you forget it.”

Parkinson spent the months after the Lonely Halls meeting selling the proposal to Pentagon staff and decision-makers. He flew to Washington as often as twice a week, holding some 60 meetings in two months (he still has a list).

He parried every doubt: Yes, the signal would be powerful enough to be detected in the surrounding noise. Yes, the system’s 10-meter accuracy was achievable. Yes, US $180 million would cover the constellation of four satellites and related ground equipment. (The final price was about $250 million, but that included two added satellites—not a horrible overrun, Parkinson says.)

“He was quite the salesman,” says Melton, his colleague in the 621B program.

The Defense Council approved the proposal in December 1973. Parkinson led the program for three and a half years, until the first GPS satellite was up in space and initial tests verified that the system worked as designed.

Easton’s atomic clock, it turns out, was not ready for that initial launch, but Parkinson had engineers at Rockwell International also working on a space-worthy atomic clock, which was ready. Parkinson still gives Easton credit.

“Easton convinced me that we could do it—and that made a heck of a difference,” he says.

The full 24-satellite system became operational in 1995. The Russian GLONASS system, a similar project begun during the Soviet era, was also completed in 1995. Both the European Union’s Galileo system and China’s BeiDou system are expected to be completed in 2020.

Bradford W. Parkinson Photo: Gregg Segal

Date of birth: 16 February 1935

Birthplace: Madison, Wis.

Education: B.S. in general engineering, U.S. Naval Academy, 1957; M.A. in aeronautics and astronautics, Massachusetts Institute of Technology, 1961; Ph.D. in aeronautics and astronautics, Stanford University, 1966

Current position: Professor emeritus, recalled to active duty, Stanford University

First jobs: Supermarket carryout and stock boy, general laborer in construction, newspaper delivery

First tech job: Surveyor for construction projects

Most surprising job assignment: As an instructor at the Air Force Academy, flying 26 air combat missions to troubleshoot the electronics on the AC-130 gunship

Patents: Seven

Most recent book read: The Winter Fortress: The Epic Mission to Sabotage Hitler’s Atomic Bomb , by Neal Bascomb

Favorite book: Tortilla Flat , by John Steinbeck

Favorite music: Classical, particularly Sergei Rachmaninoff, Edvard Grieg, and Ludwig van Beethoven

Favorite food: Spaghetti with meatballs

Favorite restaurant: Café Roma, San Luis Obispo, Calif.

How his spouse would describe him: Intense

After hours/leisure activity: These days, hiking, snowshoeing; in the past, sailing, skiing

Car: BMW Z4 and a GMC truck

Organizational memberships: IEEE, Institute of Navigation, Royal Institute of Navigation, SME, American Institute of Aeronautics and Astronautics

IEEE Medal of Honor: “For fundamental contributions to and leadership in developing the design and driving the early applications of the Global Positioning System”

Other major awards: ASME Medal, Charles Stark Draper Prize for Engineering, Marconi Prize, Royal Institute of Navigation’s Gold Medal, Institute of Navigation’s Thurlow Award

Parkinson retired in 1978 from the Air Force, but he didn’t leave GPS behind. After several positions in industry (including vice president of Rockwell International’s Space Systems Group and vice president at Intermetrics), he returned to Stanford in 1984, this time as a professor of aeronautics and astronautics. He immediately rejoined the orbiting gyroscope project, now called Gravity Probe B, as program manager and a coprincipal investigator; it successfully launched in 2004.

He also led a research group aimed at developing civilian applications for GPS technology. That work led to a robotic sailboat, the first GPS-guided landing of a commercial aircraft, and a system of ground stations that would improve the accuracy of GPS positioning by monitoring and correcting the satellite data. The last project evolved into the Federal Aviation Administration’s Wide Area Augmentation System, which uses data from ground stations to improve GPS’s accuracy by correcting errors in the signal caused, for example, by orbital drift and delays introduced by the atmosphere.

Parkinson’s group also developed the application he is most passionate about today: automated tractors. He had kept automated tractors in his sights for some time; he listed the application as part of GPS’s future in talks he gave as early as 1978.

It wasn’t until around the 1990s, though, that he got his chance to push the technology along. At Stanford, he met with a representative from John Deere who was building ties between the company and universities. Parkinson demonstrated a GPS-guided self-driving golf cart.

“Think tractor,” he told the visitor.

The Deere representative was skeptical that farmers would buy such a system, Parkinson recalls, but the company was eager to partner with Stanford and agreed to fund a development project.

“They sent us about $900,000 and two huge tractors,” Parkinson says. A team of students spent several years developing the technology, first demonstrating a fully functional system in 1997.

Watching the rise of GPS-guided precision farming since then has been gratifying, he adds. Parkinson’s home overlooks a farm, and he often walks in the fields, sometimes spotting, to his delight, a GPS-guided tractor at work. “The tractors pay for themselves in savings in fertilizer and in time.”

“I think he likes the agricultural application because it brings home that GPS is for everyone,” says Penina Axelrad, a former Ph.D. student of Parkinson’s who is now a professor at the University of Colorado. “Now, of course, GPS is in everyone’s smartphones, but that was an early application that everyone could value.”

Parkinson is now mostly retired, though he still has research projects running at Stanford.

He remains one of GPS’s biggest fans—he has more than a dozen devices in his house and car that use GPS, including a watch he wears most of his waking hours.

“He just gets so excited when he sees cool things enabled by GPS,” says Axelrad.

He is also quick to protect GPS when he feels that it’s threatened. Right now, he sees a big threat coming from Ligado Networks, which aims to create a broadband wireless network using the 1,525- to 1,559-megahertz frequency band. This band is adjacent to the frequencies used by GPS, which are between 1,164 and 1,587 MHz, nestled among other bands essentially reserved for satellite communications. Ligado’s band is reserved for Earth-to-satellite communications with some limited use of cell towers to help users connect to the network. Back in 2011, however, the U.S. Federal Communications Commission considered giving Ligado’s predecessor, LightSquared, a conditional waiver to use the frequency band for unlimited ground-based communication. The GPS industry protested, showing data on interference, and in 2012 the waiver was pulled. But Ligado recently came back with a proposal for a lower-power system that it says won’t interfere with GPS.

That proposal is still before the FCC. But testing by the Department of Transportation shows extensive interference, Parkinson says, particularly for the most accurate devices. He’s been working on an editorial to alert the public to the danger of the proposal. Ligado aims to change the designation “of a quiet signal from space to powerful ground transmitters,” he writes. “They would apparently use this to compete with the existing broadband companies. This country already has at least four broadband providers but has only one GPS.”

Says Parkinson, “We endanger it at our peril.”

This article appears in the May 2018 print issue as “GPS’s Navigator in Chief.”

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IEEE Spectrum | Robotics by Dexter Johnson - 5h ago
Flexible nanodiamonds promise to open up novel optical and electronic properties Image: Yang Lu, Amit Banerjee, Daniel Bernoulli, Hongti Zhang, Ming Dao and Subra Suresh

It’s commonly known that diamonds are the hardest natural material. However, with that hardness comes brittleness: they may be hard but they’re not very flexible.

Now an international team of researchers has demonstrated that diamonds, which are commonly believed to be inflexible, can be bent and stretched significantly. The researchers showed that the maximum tensile elastic strain of a diamond can reach nearly 9 percent, close to the theoretical limit of the material.

The researchers believe that these enhanced mechanical properties make nanodiamonds much more durable than expected, and therefore could lead to applications that involve mechanical loading, making them candidates for applications such as diamond needle-based intracellular delivery. But it is what this flexiblity does to diamonds’ optical and electrical properties may prove to be the most significant in the long run.

In research described in the journal Science , scientists from the City University of Hong Kong, China, the Massachusetts Institute of Technology, Ulsan National Institute of Science and Technology (UNIST) in South Korea and Nanyang Technological University in Singapore produced nanoscale diameter (about 100-300nm) diamond needles using reactive ion etching (RIE) of CVD (chemical vapor deposition)-grown diamond thin films.

The resulting material demonstrates that the mechanical properties of even hard, brittle crystalline materials like diamonds can be fundamentally changed when their sizes are reduced to nanometer-length scale.

While the purity of the internal crystalline structure and surface smoothness of the material is important, the key to achieving such flexibility in diamonds is actually the “size”—the dimension/diameter of the nanodiamond needles, according to Yang Lu, an associate professor at the City University of Hong Kong.

Flexibility on its own is great for using diamonds in applications that require more mechanical loading, but there is also a quantum mechanical effect that comes with this bending.

Images: Yang Lu, Amit Banerjee, Daniel Bernoulli, Hongti Zhang, Ming Dao and Subra Suresh

SEM image sequence of bending deformation of a typical polycrystalline nanoneedle, where (B) shows the maximum deformation before fracture and (C) shows the nanoneedle immediately after fracture has occurred.

Previous theoretical studies showed that when elastic strains exceed 1%, quantum mechanical calculations indicate significant physical and/or chemical material property alterations due to the changes in energy band gap structures, according to Ming Dao, principal investigator and director at MIT’s Nanomechanics Lab, who was a co-author of the research.

“These property alterations may include significant changes in mechanical, thermal, optical, magnetic, electrical, electronic and chemical reaction properties, and could be used to design advanced materials for various applications through the emerging ‘elastic strain engineering’,” said Dao. “When maximum elastic strains can be changed in real-time between 0 to 9% in nanodiamonds, there is a lot of potential for exploring unprecedented material properties.”

The resulting material demonstrates that the mechanical properties of even hard, brittle crystalline materials like diamonds can be fundamentally changed when their sizes are reduced to nanometer-length scale.

After two years of careful iterations between simulations and real-time experiments, Dao said that he and his colleagues have managed to streamline a nanomechanical process that can precisely control and quantify the maximum amount of elastic deformation within the nanodiamonds.  The resulting method enables accurate control and on-the-fly alterations of the maximum strain in the nanoneedle below its fracture limit. This also means, of course, that its electronic properties can be changed on-the-fly as well.

While this level of elasticity in the nanodiamonds can change their band gap structures, incorporating impurities into the severely strained lattice of the nanodiamonds may lead to revolutionary changes in diamond’s electronic and optical properties, according to Yu. “This could open up a lot of novel optoelectronics applications for diamonds, such as more powerful or colorful laser or maser (microwave amplification by stimulated emission of radiation),” said Yu.

The first step toward commercialization of these applications will require researchers to microfabricate diamond nanostructures in well-defined geometries and crystalline structures.

For optoelectronics applications, another challenge is to quantify and control the local optical/electronic property changes, in real time, for a single diamond nanostructure under elastic straining, according to Lu.

Lu added: “We will work with physicists and electrical engineers to explore the optoelectronics applications of the elastic nanodiamond structures, and we may even may find its applications in the emerging diamond-based quantum computing technologies.”

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This former HP engineer started his own company to exploit the newest free resource—the Global Positioning Satellite system Photo: Trimble

Next month, Brad Parkinson receives the IEEE Medal of Honor for his work bringing GPS navigation from concept to reality. Parkinson told me in January that he’d always wanted a cheap, consumer version of the technology—though he never imagined just how cheap and ubiquitous it would become.

Writing a profile of Parkinson sent me down a trail of my own—into my memory banks, to recall the others who made GPS something we can take for granted today. In addition to Parkinson, there’s Ivan Getting, whose vision set the stage for GPS today—the full text of my 1991 article on Getting is here. And there’s Charles Trimble, who shared Parkinson’s vision of consumer applications for GPS. His company, Trimble Inc., introduced its first GPS product in 1984, a system designed for off-shore oil drilling platforms. In 1994, the company brought out its first GPS receiver that fit on a PC card. The full text of that profile is below.

Charles R. Trimble

This former HP engineer started his own company to exploit the newest free resource—the Global Positioning Satellite system

In 1982 the U.S. Global Positioning Satellite program—a U.S. government plan to launch a constellation of satellites that would allow users worldwide to pinpoint their locations—was by no means a sure bet. Receiver technology was only in the research and development phase, and government budget slashing was already beginning to eat away at the project’s funding. That year Palo Alto, Calif.-based Hewlett-Packard Co., which had had four engineers working on the technology for some four years, took its cards off the table.

Whereupon Charles R. Trimble decided to get into the game. A former HP engineer then leading a struggling start-up company, he put all his chips on the Global Positioning Satellite (GPS) program, and in spite of near disaster—the Challenger explosion put the GPS program on ice for three years—the gamble proved a winner.

And those winnings ballooned into a bonanza during the Persian Gulf War, when the U.S. military turned to Trimble Navigation Ltd. For some 10,000 portable GPS receivers. That kicked the expanding company into overdrive, and it is now growing at over 100 percent annually. From last year’s revenues of US $63 million, analysts project 1991 revenues will be $145 million. The company currently has 750 employees, including some 200 engineers, an increase of 250 workers over 1990.

A quick tempo appeals to Trimble. Though a native Californian, he moves like a New Yorker late for a train, rushing from building to building in the Sunnyvale, Calif., industrial park that houses his company. In his career, too, he has always been a mover and shaker: in 14 years at HP, he was involved in four new ventures, leaving only when that company’s intrapreneurism slowed down.

Trimble had intended to work as an engineer for only three months. In 1964, he had gained a master’s in electrical engineering from the California Institute of Technology in Pasadena—which he picked in junior high school after hearing it was the hardest school to get into—and was planning to enter Harvard Business School in Cambridge, Mass., in the fall. Meanwhile, he took a summer job at HP.

“I viewed that as my only opportunity to understand the engineering world,” Trimble told IEEE Spectrum. “So I put my heart and soul into it, working as many as 90 or 100 hours a week.”

Before that summer, he had been strong on scientific theory, but had never even picked up a transistor. By Labor Day he was hooked on engineering, and called Harvard to withdraw.

Trimble blames that move on the man who hired him, Al Bagley, then head of HP’s Frequency and Time Division, and his determination to keep Trimble out of Harvard’s grasp.

Nor does Bagley deny the charge. When recruiting at Cal Tech that spring, he had heard about “this kid Trimble” from everyone—from professors to the clerks in the bookstore. The student was impressive in an interview, Bagley recalled, but did not want full-time employment. Bagley’s bait was a challenge: could Trimble build a “computer of average transient”—a digital device that could analyze signals and spot repetitive signals amid noise? If he succeeded, Bagley promised that HP would market the creation as a special-purpose instrument.

The new graduate thought the project would take two years, but it took four, and his plans for business school faded. The HP 5480 Signal Averager bowed in the fall of 1968 and became primarily a biomedical research tool.

If Bagley had had any doubts about his new hire’s intrepidity, they dissipated one stormy day during a sailing race on San Francisco Bay. Safe on shore, Bagley saw masts breaking and on one small sailboat, a wildly swaying mast with Trimble perched atop.

“That is the sign of a gutsy guy,” Bagley said, particularly in light of Trimble’s congenital eye defect. Scar tissue on the retina deprives him of all central vision He therefore cannot drive and must read through binoculars or by holding documents close to the periphery of his eyes.

INTRAPRENEURISM. When this “gutsy guy’s” computer of average transient was completed and on the market in 1968, he asked for the chance to figure out a major new business area for HPs Frequency and Time Division. Bagley agreed, and Trimble targeted real-time dynamic testing of large-scale integrated (LSI) circuits. Assembling a team of 20 people, one of the largest groups in the laboratory, he began building a computer-controlled dynamic IC tester. Though static testers of LSI chips existed, no dynamic testers were then available for that level of circuit integration.

In 1971 the prototype was completed, but money looked tight for HP for 1972, and Trimble’s project was canceled.

Then, undaunted, he started on another new project—focusing on single-shot time interval measurement and connectivity between electronic instruments and computers and calculators. One of his project managers became the instrumentation point man in the interfacing effort that led to the HP Interface Bus (HP-IB) and the IEEE 488 standard.

“When you get the reputation of a rebel, you are not going to move up in a conservative company”

Trimble’s last job at HP was as head of development for the Santa Clara-based bipolar LSI laboratory, which basically did contract engineering for other company divisions. Such a structure allowed for little discretionary work, and Trimble was interested in using the IC fabrication line to develop a new series of instruments capable of measuring time intervals as short as 50 picoseconds. So he persuaded corporate management to restructure the laboratory: in return for a fixed budget instead of total dependence on contract research, he would reduce staff and eliminate efforts in publishing and giving academic papers, which were taking up one-third of researchers’ time.

Shaping the HP way to suit his goals was standard operating practice for Trimble, according to Jim Sorden, an HP colleague who is now vice president of product engineering at Trimble Navigation. “It was well known in HP that if you wanted to beat the system, talk to Charlie, and he would figure out the way,” Sorden said.

When that project ended in 1978, Trimble looked around HP and realized that the environment had changed. The price for entrepreneurism by that time was working on projects that were 10 years from production. “HP had gone from a technology-driven to a marketing-driven to a resource-allocation company in my 14 years there, Trimble told Spectrum. It was time to go.

Colleague Sorden was not surprised. “Though Trimble did well at HP,” he said, “when you get the reputation of a rebel, you are clearly not going to move up the ladder in a company that is becoming more and more conservative.”

BOOTSTRAPPING. Trimble then turned his attention to an HP development project in Loran C navigation equipment that had been canceled. Loran C uses time differences between low-frequency radio signals from land-based transmitters to guide navigators primarily on the U.S. coastline and the Great Lakes. Trimble approached the project’s division manager and, after several months of negotiation, purchased the Loran technology for $50,000, funds he obtained through refinancing an apartment building he had purchased earlier. He left HP with two engineers from the project, Thomas Coates and Daniel Babbage, and an administrator, Kit Mura-Smith, and set up shop as Trimble Navigation Inc. in November 1978.

Though he had always been a hard worker, Trimble was in for a few surprises when he took his entrepreneurial talents outside of the sheltered corporate environment. “I thought I knew what hard work and commitment was,” he said. “But I was totally unprepared for the set of emotions and stresses involved in trying to bootstrap a business from zero.”

On his own, survival was the No. 1 concern. Trimble said he was lucky to get through the early days: “I’m at a disadvantage in the $0-$2 million business level—I’m a strategist, not a street fighter.”

By 1982 Trimble Navigation was selling about $1 million of Loran equipment annually. But growth in the Loran market was flat, so he began looking for a new business area to pursue. He found it again in the reject pile at HP.

The company had canceled a development program for navigation products that used the nascent Global Positioning System. AT the time, plans called for GPS to be completed by 1987.

Trimble, enthralled with the idea of GPS as a free information utility ripe for commercial exploitation, bought the rights to an HP GPS breadboard in the summer of 1982. With the help of HP’s original design team, doing after-hours consulting, he drafted a fundamental GPS block diagram, which he considers his best piece of technical work to date.

“I was totally unprepared for the emotions and stresses involved in trying to bootstrap a business from zero”

But Trimble lacked the time to work through several generations. He needed a product he could sell within 11 months, at which point, he calculated, the company would run out of money.

The product area he chose was an obscure one—time calibration of cesium clocks, using atomic clock signals from PS satellites to calibrate the clocks at naval observatories—at best, a $1-million-a-year market.

Trimble knew that once the GPS constellation was complete, his $1.8 million company would have to have grown up, with revenues of at least $50-$100 million annually, because large competitors would then jump into the business. “We needed the resources to play in the end game,” said chess player Trimble. The company required growth of 60 percent a year, and he consistently met and exceeded that.

In 1985 Trimble Navigation introduced GPS positioning for offshore oil surveying and developed a GPS navigation sensor for aviation (of use to pilots when the GPS constellation was complete).

Then in January 1986, with only seven GPS satellites in orbit, the Challenger blew up. GPS launches were put on hold until a new rocket booster could be developed for GPS satellites—a delay of three years.

“With the satellites up there, we could survey to 25 meters, which was good enough for offshore use,” Trimble said. “If one satellite died, we could still survive. If two died, we would have been in deep, deep trouble.” Meanwhile, the collapse of oil prices hurt the offshore survey marketplace.

So the company began looking for customers that were unconcerned about the number of satellites in the sky because they were confident of GPS’s efficacy in the future. The prime candidate was the U.S. military, but the military had let an exclusive end-user receiver contract to Rockwell International Corp.-Collins Avionics and Communications Division through 1992, covering all the GPS applications it could think of.

The task for Trimble was to figure out applications Rockwell and the military had overlooked by assuming receiver equipment must cost a lot. He came up with a GPS brain for remotely piloted vehicles and personal position finders for the infantry, and soon created a small rugged finder that could be carried in the hand, in a pouch at the waist, or around the neck. The military took the bait, ordering 1000 Trimpacks at $4000 each, deliverable in May of 1990.

GULF BONANZA. When Saddam Hussein invaded Kuwait, the U.S. military began escalating its orders. Another 1000 unites were purchased, then nearly 9000 more. Trimble went from a company shipping $5 million in products a month to one shipping $19 million a month just six months later—all the while hanging by its nails as components grew ever harder to obtain.

The only shadow on this success story is Trimble’s dislike of being thought of as a military contractor His is primarily a commercial and consumer products business, and he wants to keep any military manufacturing down to less than 20 percent.

Trimble cut his management teeth at HP and has, he said, managed the HP way ever since He defines this managerial style a one of trading autonomy for commitment.

But autonomy does not mean hands off. On a summer’s morning as observed by Spectrum, Trimble sprinted from meeting to meeting, carrying no documents and taking no notes, but seemingly up-to-speed in every area—from review of current chip designs in development, to government lobbying concerning export controls, to personnel requisitions, to new product proposals, to plans to push defects closer to zero. Mostly he listened, occasionally he asked questions, and often he stumped his engineers.

Charles R. Trimble

Date of birth: Aug. 20, 1941

Place of birth: Berkeley, Calif.

Height: 175 cm

Weight: 77 kg

Family: wife, Marcia, daughter, Melinda age 13

Education: B.S. in engineering (physics), 1963, and MSEE, 1964, California Institute of Technology

First job: selling avocados door to door

Oddest job: growing oat roots for biomedical research

Recent reading: Tucker’s Last Stand by William Buckley

Favorite composers: Mozart, Strauss

Most respected role models: David Packard, Al Bagley, and Robert Cooper (former head of NASA’s Goddard Space Flight Center)

Dislikes: Brussels sprouts

Favorite movies: Dances with Wolves, Soapdish

A favorite expression: “Our assumptions are more confining than the laws of physics”

Leisure activities: sailing, cycling, chess

Pet peeve: when the person doing most of the talking has nothing to say

Management credo: “Trade autonomy for commitment”

Modeling complex problems simply so they can be solved by himself or others—be the problems scientific, engineering, or economic—is one of Trimble’s strongest talents. In fact, he said, detail bores him. Ralph Eschenbach, vice president of avionics and sensors at Trimble Navigation, thinks this aversion to detail relates to Trimble’s eyesight, which identifies overall shapes better than fine detail. “He tends to force things into simplified models and doesn’t get trapped with details,” Eschenback said.

Trimble himself attributes this skill to his family’s practice of doing mental math games on long car drives, and to Cal Tech professor R. David Middlebrook, who insisted that students solve a problem on a single page.

These days, he said, his job is “to gather people around me who are far more talented than I am. It is their turn to generate the inventions.”

TO PROBE FURTHER. Trimble Navigation Ltd. Has published an explanatory guide to Global Positioning System (GPS) technology, called “GPS, a guide to the next utility,” (1989).

“Navstar: the all-purpose satellite” [IEEE Spectrum, May 1981, pp. 35-40] discusses the technology behind GPS and the original intentions for such a system.

Originally published in IEEE Spectrum, February 1992, pp. 46-48.

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The founding president of the Aerospace Corp. was the force behind the Navstar global positioning system of satellites Photo: Alfred Eisenstaedt/The LIFE Picture Collection/Getty Images

In 1991, I sat down with Ivan Getting, then age 79 and retired but still serving on the boards of directors of several companies. The U.S. satellite navigation system, now referred to as GPS, then more commonly called Navstar, wasn’t complete, but covered most of the world and had proved essential to the U.S. military in the Persian Gulf War. We thought Spectrum’s readers would want  to know more about how Getting came to play such a big role in making Navstar.

I had no idea at the time just how much GPS would come to mean personally, to me and just about everyone. Getting had some good stories to tell, so I was interested, but GPS hadn’t changed my life—at least, not yet.

Getting was the first satellite navigation pioneer to tell me his story, but not the last. The next year I interviewed Charles Trimble, founder of Trimble navigation and one of the first to bet his company on the commercial possibilities of satellite navigation; the full text of that profile is here. (In just that short year, we’d stopped calling the technology Navstar, it was now and going forward GPS.)

This year, I met with a third key figure in the history of satellite navigation, Brad Parkinson, who, as an Air Force colonel, took Getting’s vision of satellite navigation and ran the program that got that system spec’d out and launched (literally). Next month, Parkinson will receive the 2018 IEEE Medal of Honor for his work.

This time I knew how much of a difference GPS made to the world and to me, so was more than a little excited. On the way to meet Parkinson, I also thought about what I’d perhaps lost—once in a while in that pre-GPS past, wrong turns led to even better destinations than those originally targeted. But the net gain has been a huge, even though my children will never know how to read a Thomas guide or a AAA Triptik.

What follows below is my 1991 article profiling Ivan Getting. It covers the development of Navstar, along with an early project in Getting’s career which evolved into the “Scudbuster” used in the Gulf War, other technical projects, and the origins of the Aerospace Corp.

But my favorite Getting quote from that 1991 profile interview isn’t about technology—it’s about work environments. When Getting first joined Raytheon in 1951, he recalled, the company crowded its engineers into large open areas. But Getting thought engineers would be better served by private offices.

“I had been a working engineer myself,” Getting told Spectrum. “I didn’t want to be one of a thousand. I wanted individuality. Scientists and engineers, if they are any good, want individuality; they want an opportunity to get together with other engineers, but they don’t want to be herded like sheep. And the cost of adequate office space is the smallest part of the total cost of operating a high-tech company.”

I wonder what this pioneering engineer would think of Silicon Valley’s workplaces today.

Ivan A. Getting

The founding president of the Aerospace Corp. was the force behind the Navstar global positioning system of satellites

Part of the coalition forces in the Persian Gulf might have been lost in the dessert were it not for a vision that Ivan A. Getting had in 1960 and pursued relentlessly for the past 30 years. At the very least, the military might not have been able to locate their precise positions or know exact coordinates as easily, a crucial advantage in commanding and controlling forces in the desert and on the sea, and in deploying surgical-strike weapons.

Getting’s vision is Navstar, the global positioning system of satellites. It dates to the 1940s, when Getting was a researcher working on radar weapons control systems at the Radiation Laboratory at the Massachusetts Institute of Technology (MIT) in Cambridge. His colleagues in a nearby lab were developing the navigation system used today by ships and planes, Loran. Using land-based transmitters to send signals to a receiver on the missile, Loran compares the arrival times of the different signals to calculate its position.

“Ivan is relentless in pursuing an objective”

In the 1950s, as head of research and engineering at Raytheon Corp., Waltham, Mass., Getting led a project to develop a mobile ballistic missile guidance system called Mosaic, which was to work like the Loran system. But Getting envisioned another concept. Though the railroad mobile version of the intercontinental ballistic missile was cancelled, he realized that if a similar system were used, one that based the transmitters on satellites, and if enough satellites were lofted so that four were always in sight, it would be possible to pinpoint locations in three dimensions anywhere on earth. This theory led to Navstar.

In 1960 Getting was asked by the U.S. Air Force to create a nonprofit military systems development organization, the Aerospace Corp. in El Segundo, Calif. During the hectic early days of building the new company, he assigned a planning group to look at the feasibility of his idea to navigate globally by satellites. Though as president of the Aerospace Corp. he took on many complex projects—planning new ballistic missile systems, overseeing space launch systems, and developing high-powered chemical lasers—global satellite navigation remained his constant passion.

FINDING FUNDS. It was clear from the start that Navstar would require at least 18 satellites for worldwide coverage and would cost billions of dollars.

His biggest concern, he recalled, “was to get the damn thing funded.” He became an evangelist for Navstar, promoting it at every opportunity to the presidential science advisor and to the heads of the various armed forces. “I was selling everywhere, promoting, promoting,” Getting said.

“Ivan is relentless in pursuing an objective,” Sam Tennant, the current Aerospace Corp. president, told Spectrum. “Navstar was not a program that came easily. In the early days, there were few believers.”

But eventually people started buying into Getting’s project, although with some reluctance. The Air Force consented to fund a study. The R&D board of the Department of Defense agreed to fund a technology demonstration. And finally, the Department of Defense approved funding of the development and deployment of a complete Navstar system, costing some US $10 billion.

The first Navstar satellite was launched in 1978; by 1985 enough satellites were in orbit for Navstar to be used, in at least two dimensions, in most areas of the world. Complete worldwide coverage was expected to be available by 1987, but the launch schedule was set back by the Challenger disaster. Its scheduled completion date, with 18 satellites sending out signals, is now set for 1993.

Navstar now fully covers the Persian Gulf area, and coalition forces carry thousands of receivers that can calculate positions within accuracies of less than about 9 meters (30 feet).

Today Getting is theoretically retired, but he shows little sign of slowing down and talks warmly about the experiences of his long career. When he is not on the road, advising companies and the Department of Defense, he spends much of his time in a crowded office in his Brentwood Park home in Los Angeles, a stone’s throw from Hollywood stars. There, he is surrounding by stacks of documents demanding attention (his filing system has deteriorated since he gave up corporate life and the personal secretary that went with it.) In his free moments, he retreats to a tiny backyard greenhouse, where he raises orchids.

PATRIOT PREDECESSOR. Navstar was not the only military technology used in the Person Gulf conflict associated with Getting’s research efforts. The Patriot missile—the so-called Scudbuster—uses radar and computers to home in on attacking missiles. It is a sophisticated version of a radar-based automatic antiaircraft system Getting worked on during World War II—the SCR-584.

This was the first system to use radar and computers to calculate missile paths. It was a hands-on project: Getting and his team built a demonstration system in 1941, working in an old World War I hangar at MIT, in the middle of the winter, with no heat. By 1944 some 300 SCR-584s were placed around London, and they logged a success rate of 95 percent in shooting down Germany’s V-1 cruise missiles.

The SCR-584 also tracked the V-2 ballistic missile (a forerunner of the Scud) and traced its path backward—to its launch site—as well as forward; launch site coordinates could be quickly radioed to fighter-bombers and swiftly attacked. When the Patriot was designed this feature was deleted from the system specifications, Getting said, because of concern that such a capability would cause the Patriot to be classified as an offensive, rather than defensive, weapon.

For his work on the SCR-584, Getting received the Medal of Merit from President Harry Truman in 1948, one of 15 scientists so recognized that year.

CAREER CHOICE. While Getting’s parents did not have a scientific bend—his father was involved in Slovakian politics and publishing—Getting seems to have been born with an interest in technology.

But the choice of military engineering seemed less ordained. Getting did not spend his childhood building model aircraft or in fantasizing about building real planes and tanks. Rather, he fell into a military career almost in spite of himself.

As a child in Perth Amboy, N.J., he received a hand-me-down Meccano set—a toy that competed with Erector sets—consisting of plates, gears, axles, and other metal parts. With the set, he figured out how a car’s differential worked. He went on to study physics at MIT, winning a scholarship in a contest to find Edison’s successor. Graduating in 1933, the depts. Of the Depression, Getting had no hope of finding a job in his field, so he applied for a Rhodes scholarship and studied astrophysics at Oxford University in England. This was followed by studying nuclear physics at Harvard University in Cambridge, Mass., where he developed the first high-speed flip-flop.

“I didn’t want to be one of a thousand, I wanted individuality”

Then, he says, “I got trapped by the war.” The Radiation Laboratory was established at MIT to work on radar as part of the war effort, and a Harvard scholar in the office next to Getting’s was tapped to head the project. He recruited Getting, reasoning that the circuitry Getting had been developing to examine cosmic rays could be applied to radar.

When the war ended in 1945, the Rad Lab was disbanded. Getting chose to stay at MIT as an associate professor of electrical engineering, intending to do research in nuclear power, which he considered a vital field. “We need power for everything we do, from lights to producing fertilizer,” he explained. “This was an opportunity to make what was considered an infinite source of power.”

But the doors to nuclear power research were locked because of concerns over security—only people who had been in nuclear research during the war could get in. So Getting turned his research to electron accelerators, building a 350-mega-electronvolt synchrotron. Lack of a synchrotron industry, however, forced him to focus his consulting on military systems and radar. After war broke out in Korea in 1950, the Air Force wooed him to its staff in the position of assistant for development planning. His career path in military systems was set.

GREATEST BLOOPERS. While Getting’s successes have been formidable, he is the first to admit that he has made his share of mistakes. Early in his career, these errors taught him to pay attention to even the smallest details of an engineering effort.

In 1939 at Harvard, Getting worked feverishly to repeat a German experiment and be the first in the United States to demonstrate fission. Using an old bell jar to create a cloud chamber within which to observe fission reactions, he took thousands of pictures—but none showed fission particles. After Columbia University in New York City announced that it had demonstrated fission, Getting discovered that his bell jar was very old and had been made of boron glass, which absorbed the slow neutrons needed to produce fission of uranium.

The following year, in an attempt to test radar tracking at the Rad Lab, Getting inflated a rubber balloon with hydrogen. Over the balloon he draped reflective aluminum material attached to raw silk. But the balloon rubbed against the silk in the wind, creating a static charge, then a spark, then an explosion that singed Getting’s hair and eyebrows.

When Raytheon in 1950 had a problem with tubes that met their specification tests in the factory but failed in the Navy acceptance tests of the altimeters, production stopped while the problem was investigated. It turned out that a technician making final adjustments was using an unmatched homemade radio-frequency coaxial cable instead of a standard production cable. It cost the company $300,000 to find the error, and throughout his tenure at Raytheon, Getting kept that cable in his desk as a reminder of what can happen when a detail is missed.

This learned obsession with details, which Getting tried to impress on every employee, served the Aerospace Corp. well when it took on the responsibilities of manned space launches. Aerospace oversaw all the launches in the Mercury and Gemini programs, and the company impressed on every contractor the importance of tender loving care—paying attention to every detail. “We never lost a single astronaut,” Getting said. When TLC was reduced, the inevitable human error did slip through.

ENGINEERING ENVIRONMENTS. After his first few years at the Rad Lab, Getting made his first move from engineering into management. But once the lab folded in 1945, he turned down several offers of engineering management jobs to return to university teaching and research. However, he was persuaded in 1950 to move to the Air Force staff, and he never went back to hands-on engineering.

As a manager, Getting believed in treating employees with respect and care, even though this was counter to many corporate philosophies at the time. When he joined Raytheon as vice president, engineering and research, in 1951, the company, like many of its New England competitors, housed its engineers in old brick textile factories, crowding them into large open areas.

But Getting knew that engineering environments could be different, and that AT&T’s Bell Laboratories, Murray Hill, N.J., had made a start in effecting such a change by building attractive, landscaped, pleasant facilities for its engineers, giving each a private office. He thought Bell had the right idea and launched a building program at Raytheon on Route 128 outside Boston.

“I had been a working engineer myself,” Getting told Spectrum. “I didn’t want to be one of a thousand. I wanted individuality. Scientists and engineers, if they are any good, want individuality; they want an opportunity to get together with other engineers, but they don’t want to be herded like sheep. And the cost of adequate office space is the smallest part of the total cost of operating a high-tech company.”

Besides prime facilities, Getting advocates giving engineers a chance to get credit for what they accomplish, and as much public recognition as possible. This is not always easy for military contractors, when engineers are barred for security reasons from even mentioning their work to their families.

Max Weiss, a former director of Aerospace’s R&D laboratories and now vice president of Northrop Corp., Los Angles, told Spectrum that Getting seemed able to provide this positive motivation intuitively. “He would take a younger man, put his arm around him, and encourage him, Weiss said. “He gave me a lot of self-confidence and encouraged my initiative. Today we would call it empowerment.”

Ivan Alexander Getting

Date of birth: Jan. 18, 1912

Place of birth: New York City

Height: 182 centimeters (6 feet)

Weight: 93 kilograms (204 pounds)

Family: married twice, to Dorothea (died 1976) and Helen; three children

Education: S.B. 1933, Massachusetts Institute of Technology; D. Phil., 1935, Oxford University

First job: playing piano in a jazz orchestra and organ in a church

Patents: six

Most recent book read: Modern Radar System Analysis by David K. Barton

Favorite kind of music: classical piano

Favorite food: smoked salmon

Least favorite food: broccoli

Favorite expression: “It’s not what I say, it’s what I mean”

Favorite leisure activity: growing orchids

Pet peeve: people trying to explain something when they don’t know what they are talking about

Annual air mileage: 300,000 kilometers

Management credo: “Select good people, give them responsibilities they understand and you understand, and then follow up”

Memberships and awards: 1948 Presidential Medal for Merit; Fellow, President (1978) and Founders Medal, IEEE; Honorary Fellow, American Institute of Aeronautics and Astronautics; member, National Academy of Engineering; the Kitty Hawk Award

Since his retirement in 1977, Getting seems barely to have slowed down. He served as IEEE President in 1978, is currently a member of the board of directors of several companies, and is on the Air Force Scientific Advisory Board as well as on the Navy Studies Board of the National Research Council—responsibilities that require several trips a month from his home in Los Angeles to Washington, D.C.

Northrop vice president Weiss told Spectrum that Getting is invaluable on such boards and committees because he asks penetrating questions in a disarmingly naïve way. “He’ll say: ‘Forgive me, I’m an old man, you’re smarter than I am, you’ll have to explain this to me,’ “ according to Weiss. Then he will zero in with a pointed question.

All these activities leave Getting little time for raising orchids, a hobby he began in the 1930s, or playing the piano. (He occasionally accompanies TRW founder Simon Ramo, a violinist.)

And, since Navstar is not quite completed yet, and plans for future generations are still being made, Getting, now age 79, is still evangelizing.

TO PROBE FURTHER. Ivan Getting published an autobiography entitled All in a Lifetime, Science in the Defense of Democracy (Vantage Press Inc., New York, 1989). For a detailed look at the workings of the Navstar Global Positioning Satellite System, see “Navstar: the all-purpose satellite, IEEE Spectrum, May 1981, pp 35-40.

Originally published in IEEE Spectrum, April 1991, pp. 74-76

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The customer parks the car over a garage-floor charging plate, then comes back in the morning to a full battery Illustration: WiTricity

In the coming months, an unnamed manufacturer will bring an electric car to market that offers wireless charging from WiTricity, Alex Gruzen, the company’s chief executive, tells IEEE Spectrum.

Unnamed, yes, but not utterly un-guessable. Among the companies that have demonstrated wireless charging are BMW and Hyundai. And, though there are other wireless charging companies out there—Qualcomm, for example—Hyundai has explicitly named WiTricity as the supplier of the system it showed on its new Kona EV last week at the Geneva Motor Show. Other companies known to be working with WiTricity include Honda, Nissan, and Toyota.

Photo: WiTricity A Hyundai Kona recharges with WiTricity’s wireless system at the 2018 Geneva Auto Show.

Magnetic resonance was developed at MIT in the early 2000s. It works by establishing a kind of duet between an oscillating magnetic field in a pizza-box size charger on the floor and a receiver mounted under the car.
The charger and receiver are tuned to resonate, which is why little energy goes astray, making transmission as efficient as you’d get from a cable.

"There’s often a misconception that somehow plugging in is 100 percent efficient," Gruzen says. "But a plug-in is from just 88 to 94 percent efficient; WiTricity's wireless system runs at 90 to 93 percent.”  

The resonance also gives you a certain leeway in aligning the car and the charging plate. The vertical clearance can be as little as 10 centimeters (4 inches), for a sports car, and as much as 25 cm, for an SUV. The left-to-right positioning need be only within 10 cm of dead center. The fore-and-aft error—which is easier for a driver to control—is 7.5 cm.

Drivers shouldn’t take long to get the hang of parking close enough to the charger on the first try. That ease of use is the entire point.

“About 70 percent of plug-in customers never bother to plug in,” Gruzen says. “They don’t want to deal with cables. And broad, mainstream consumer behavior does not change, as it might with the 1 percent who are early adopters. I plug in every day—I’m a career-long tech early adopter—and let me tell you, it’s a pain in the ass.”

So wireless charging for EVs isn’t just a trick; it’s a marketing necessity. And for it to catch on, it’ll have to be affordable.

Gruzen says it costs US $800 for a complete set—that is, for the receiver on the car, the transmitting pad, and the charging unit that connects to it. And,  if the product comes to be offered as a standard feature in cars, it might add just $300 or so to the price of the car.

Illustration: WiTricity

I ask him why anyone would want a slow-charger at a parking spot when he can have access to fast-charging stations, such as the ones Tesla’s building. He says there simply won’t be enough grid capacity to supply power to enough fast-charging stations once EVs throng the roads.

“Fast chargers? It’ll be like the gas lines of the 70s, queuing up for your spot,” he says. “We want people to be able to start their day with a full battery charge, and when they park at work, it starts charging again, without any intervention or work. Real plugging in is something you do only when you’re in transit and you need a range extender.” 

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This gadget projects light onto the ground to help you remain visible at night David Schneider

Bicycling at night can be dangerous, particularly if you don't put much effort into making yourself visible to drivers. Alas, many people don't. This video describes the construction of an Arduino-controlled rear light meant to make a cyclist more visible by throwing a sequence of red spots on the ground adjacent to the bike. It's not a perfect insurance policy by any means, but it's better than what many people are doing—riding about on bikes at night with little or no light to advertise their presence.

Read more: Build an Attention-Grabbing Bicycle Light

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These robots are slow, careful, and successful, making them way better than humans at assembling an Ikea chair Image: NTU

Apparently, one of the standards by which we should be measuring the progress of useful robotic manipulation is through the assembly of Ikea furniture. With its minimalistic and affordable Baltoscandian design coupled with questionably creditable promises of effortless assembly, Ikea has managed to convince generations of inexperienced and desperate young adults (myself included) that we can pretend to be grownups by buying and putting together our own furniture. It’s never as easy as that infuritatingly calm little Ikea manual dude makes it look, though, and in terms of things we wish robots would solve, Ikea furniture assembly has ended up way higher on the priority list than maybe it should be. 

We’ve seen a variety of robotic systems tackle Ikea in the past, but today in Science Robotics is (perhaps for the first time) a mostly off-the-shelf system of a few arms and basic sensors that can put together the frame of a Stefan chair kit autonomously(ish) and from scratch.

This research comes from the Control Robotics Intelligence (CRI) group at NTU in Singapore, and they’ve been working on the whole Ikea chair assembly thing for a while. First, they had to teach robots to insert those wooden pins that Ikea uses to connect parts to one another:

Then you’ve got multiple pin insertion under uncertainty:

Next, cooperatively moving partially assembled chair pieces around:

And finally, bimanual whole-chair manipulation:

The research being presented today in Science Robotics is essentially a synthesis of these skills, all put together resulting in a fully autonomous Ikea chair frame assembly:

To help put this research in perspective, let’s briefly take a look at a few other attempts at Ikea furniture assembly by robots, both from 2013:

Willow Garage:

IkeaBot:

IkeaBot in particular is notable because it’s fully autonomous— the system doesn’t require human input of any sort, not even instructions. Rather, it uses a reasoning system to determine the best way to fit all of the parts together, utilizing all available holes for fasteners and all available parts, and follows its own optimized assembly technique to end up with a piece of furniture that ends up being what Ikea intended it to be almost by default.

The assembly process from CRI is not quite that autonomous; "although all the steps were automatically planned and controlled, their sequence was hard-coded through a considerable engineering effort." The researchers mention that they can "envision such a sequence being automatically determined from the assembly manual, through natural-language interaction with a human supervisor or, ultimately, from an image of the chair," although we feel like they should have a chat with Ross Knepper, whose IkeaBot seemed to do just fine without any of that stuff. 

What is different about this new research is that it relies on very simple (deliberately simple) COTS (commercial off the shelf) hardware. There are two Denso industrial arms, Robotiq parallel grippers, force sensors, and a single depth camera. The system used no fiducials and no motion tracking, and although it did take 20 minutes (11 minutes of which was motion planning), randomly scattered chair parts were successfully turned into a chair frame in one single take. And really, 20 minutes is not that long— not even long enough to enjoy a surprisingly affordable meal of traditional meatballs with a side of lingonberries. 

And in case you were wondering whether robots are fundamentally better at putting together Ikea furniture than you are, this should make you feel (a little bit) better:

Too bad all of those clips cut out just before the robot grabs the piece and throws it against the wall while screaming incoherently.

[ Science Robotics ]

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Commonwealth Fusion Systems has pledged to build a commercial fusion reactor based on new superconducting magnets Image: Ken Filar, PSFC Research Affiliate

Fusion power is always two or three decades away. Dozens of experimental reactors have come and gone over the years, inching the field forward in some regard, but still falling short of their ultimate goal: producing cheap, abundant energy by fusing hydrogen nuclei together in a self-sustained fashion.

Now an MIT spin-off wants to use a new kind of high-temperature superconducting magnet to speed up development of a practical fusion reactor. The announcement, by Commonwealth Fusion Systems, based in Cambridge, Mass., caused quite a stir. CFS said it will collaborate with MIT to bring a fusion power plant online within 15 years—a timeline faster by decades than other fusion projects.

CFS, which recently received an investment of US $50 million from Eni, one of Europe’s largest energy companies, says the goal is to build a commercial fusion reactor with a capacity of 200 MWe. That’s a modest output compared to conventional fission power plants—a typical pressurized water reactor, or PWR, can produce upwards of 1,000 MWe—but CFS claims that smaller plants are more competitive than giant, costly ones in today’s energy market.

It’s certain that, between now and 2033, when CFS expects to have its reactor ready for commercialization, the company will face a host of challenges. These revolve around key milestones that include: fabricating and testing the new class of superconducting magnets, and using them to build an experimental reactor, which CFS named SPARC; figuring out how to run SPARC so that fusion reactions inside the machine can produce excess energy in a continuous manner, one of the biggest challenges in any fusion reactor; and finally, scaling up the experimental design into a larger, industrial fusion plant. 

Each of these steps embodies numerous scientific and engineering quandaries that may have never been seen before or have already confounded some of the smartest physicists and nuclear engineers in the world. Can CFS and MIT finally harness fusion power? Maybe. In 15 years? Probably not. 

“Fusion research remains fusion research,” says Robert Rosner, a professor of physics at the University of Chicago and the former director of Argonne National Laboratory. “It’s a field where getting to a practical, energy-generating reactor is not an engineering issue, but a basic science issue.”

“Fusion research remains fusion research.” —Robert Rosner, University of Chicago

Most experimental fusion reactors are based on a Russian design called a tokamak. These machines employ a powerful magnetic field to confine a cloud of hot ionized gas, or plasma, in the shape of a donut. This creates the extreme temperatures—in excess of 100 million degrees Celsius— for hydrogen nuclei to speed around and collide, fusing into heavier elements, like helium. The process releases vast amounts of energy. (Fusion is what powers stars like our sun, with their mighty gravity squeezing the hydrogen nuclei into helium.) 

CFS and MIT plan to build a tokamak with technology never before employed in fusion. It will generate a magnetic field using a relatively new high-temperature superconducting material made from steel tape that’s coated in a compound called yttrium-barium-copper oxide, or YBCO. The advantage of using this material is that it can produce intense magnetic fields from a much smaller machine than those at other facilities. 

CFS estimates that SPARC will be about one-fourth the size (and 1/65 the volume) of the 23,000-metric ton machine called ITER, the world’s largest experimental tokamak, currently under construction in France. Yet SPARC’s magnet will generate a maximum magnetic field of 22 teslas, nearly double that of ITER’s 12-T magnetic field.

Although MIT has pioneered research in tokamak magnetics and has persisted in exploring the high magnetic field approach to fusion, nobody has made superconducting magnets of that size and strength from YBCO, says Tim Luce, head of operations and science at ITER. “There are a lot of technological challenges associated with that,” he says. 

“We think that the MIT projection of 15 years to a power plant is very ambitious, if not overly ambitious.” —Tim Luce, ITER

MIT expects it will take three years to design, fabricate, and test the magnets. For comparison, ITER’s magnets, which consist of 18 units made from niobium-tin and niobium-titanium, are still being built, with final assembly scheduled for 2022 (the ITER project began in 2007). 

There’s also the question of fuel. The sun with its intense gravity and pressure is able to produce fusion using ordinary hydrogen. But hydrogen gas doesn’t work well in a fusion reactor because the nuclei do not collide reliably. 

To improve the chances of fusion, plasma physicists prefer two gases that are isotopes of hydrogen: deuterium, which is abundant in seawater, and tritium, a form rarely found in nature because it naturally decays with a half-life of about 12 years. A deuterium-tritium mixture, called D-T, has the greatest potential in the near-term for a sustainable fusion reaction that lasts more than a few minutes. But using that mixture has a downside: It produces large amounts of free neutrons, whose lack of an electrical charge allows them to escape the tokamak’s magnetic field. This stream of neutrons reacts with the nuclei of metals in the containment vessel to form new isotopes that can produce harmful radiation or make the vessel material brittle and vulnerable to cracks. 

“Any tokamak must run for years to optimize the plasma before daring to use tritium,” says Daniel Jassby, who was a principal research physicist at the Princeton Plasma Physics Laboratory until 1999.

Tokamak designers who have used D-T fuel—or plan to use it—have come up with creative solutions to deal with the neutrons. ITER engineers, for instance, are designing a water-cooled steel structure about 1-meter thick that will line the inside of the machine. Both the Tokamak Fusion Test Reactor, which the Princeton Plasma Physics Lab operated from 1982 to 1997, and the Joint European Torus, operating at Culham Centre for Fusion Energy in Oxfordshire, U.K., simply surrounded the entire machine in a thick concrete shield.

CFS and MIT want to develop a molten salt blanket that will surround the plasma and behave as a kind of neutron-absorbing lining. Although circulating molten salt has been used in fission nuclear reactors, no one has ever developed such a technology for use inside in a tokamak.

In an email to IEEE Spectrum, Robert Mumgaard, CEO of CFS, writes that this collaboration is different than others dominated by government funding with a focus on basic research. In this partnership, MIT will carry out the basic and applied research and CFS will work to commercialize it.

“By involving private industry focused on delivering a working product, the project and company will be able to grow and accelerate upon success, bringing more human and monetary resources to bear,” he says.

“We think that the MIT projection of 15 years to a power plant is very ambitious, if not overly ambitious,” says Luce, of ITER. “But we will celebrate any success, and we share the dream of making energy from fusion.”

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