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An almost Machiavellian plot pitted Fairchild against Texas Instruments
In one corner stood the defending champion, Texas Instruments. In the other stood the challenger, Fairchild Semiconductor. The referee, judge, promoter, and only spectator was Polaroid. In contention was the contract for the electronics of Polaroid’s secret project—a pioneering product introduced in 1972 as the SX-70, a camera eventually purchased by millions of people.
As the embodiment of truly automated instant photography, the SX-70 fulfilled a long-held dream of Edwin Land, founder of Polaroid Corp., Cambridge, Mass. Vital to this “point and shoot” capability was a new film—one that would develop while exposed to light and so eliminate the tear-away covers of previous Polaroid films. Also vital were sophisticated electronics to control all single lens reflex (SLR) camera functions, including flashbulb selection, exposure control, mirror positioning, start of print development, and ejection of print. These circuits were divided into three modules, one each for motor, exposure and logic, and flash control. At the final count, some 400 transistors were used.
This article was first published as "The battle for the SX-70." It appeared in the May 1989 issue of IEEE Spectrum. A PDF version is available on IEEE Xplore. The diagrams and photographs appeared in the original print version.
Yet this complicated system had to fit in a package the size of Land’s jacket pocket, he decreed—a constraint that meant employing ICs. But as Polaroid could not fabricate ICs, the success of its SX-70 project lay in the hands of outsiders.
The flash control contract was given to General Electric Co. Then in 1971, when GE dropped out of the IC business, it was issued to Sprague Electric Corp., as well as to Fairchild Semiconductor Corp. of Palo Alto, Calif., and Texas Instruments Inc. of Dallas, Texas. Only Fairchild and Sprague ended up producing flash controllers.
Independent contracts to develop the motor and exposure control modules went to Fairchild and TI. The motor control module contained a linear control IC, an NPN motor drive transistor, and a discrete PNP dynamic braking transistor, and gave the designers little trouble. The exposure control module was a different story.
Included in the exposure control were three ICs (early Fairchild versions had four). The exposure timer used the current output of a silicon photodiode to regulate how long the shutter blades remained open. The delay-timing circuit generated four intervals: a delay of 40 milliseconds before the shutter opened; the time the shutter remained open before the flash was fired; the duration of the flash; and the maximum exposure time given certain ambient lighting. The power control IC drove the solenoids and motor control unit. And this all had to fit on a board that fit into a 27-by-95-by-2-millimeter space, minus a central hole for the camera lens.
Stopping an electric motor by placing a short circuit across the armature of the motor; the kinetic energy is then dissipated in wiring and short-circuit losses.
Automatic metering of the light entering the camera’s lens and striking the film. In the SX-70, adjustments to affect the amount of light were performed by just one pair of blades, which controlled both the aperture and the shutter speed.
Circuitry that automatically selects the next unused bulb from the flash bar and generates a pulse to fire the bulb. It is activated automatically when a flash bar is inserted, but is inhibited when the film counter reaches zero.
Circuitry that directs the cycle of applying power to the motor and motor braking in response to signals from the exposure control.
A camera viewing system that, by swinging an angled mirror temporarily between lens and film, allows a person looking into the viewfinder to seem to see through the lens, previewing the image that will be captured on film.
Electrical noise was a major stumbling block. The photocell, for instance, operating with as little as 15 picoamperes, had to maintain its state in an environment in which the motor, the solenoids, and the firing of the flash lamps drew amperes of current. Designers were to take steps like inserting a delay between the release of the solenoids and the start of the photocell-timed exposure; redesigning circuitry on the power supply line to reject noise from the motor; increasing the voltage difference between logic highs and lows, so noise spikes would no longer masquerade as bits; and including a low-pass filter.
As it was 1969, there were no semicustom ICs, gate array technology was in its infancy, and only primitive packaging was available—standard dual in-line packages (DIPs) were at least 0.125 inch thick—while logic and power transistors could not yet share the same piece of silicon. And Polaroid wanted to buy this exposure controller for US $5.75.
Polaroid chairman Land and TI chairman Patrick Haggerty were old friends. On a weekend trip decades before the SX-70 project, they had discussed how electronics might one day make a truly one-step camera possible. The idea was to work on this dream together as soon as the technology arrived. So it came as no surprise when TI was charged with developing the camera’s exposure control board. Land was counting on TI for a fail-safe design, based on analog circuitry and proven technology and therefore reliable, reasonably priced, and capable of being produced on schedule.
Polaroid also asked Fairchild, which it viewed as the country’s leader in IC technology, to tackle a design that would push the state of the art. Fairchild’s version was to be digital and highly integrated, even to combining power transistors with logic on one chip. To Polaroid the approach looked risky, but its engineers were excited by its possibilities. Still, some within Polaroid thought the Land-Haggerty relationship made nonsense of using anyone but TI.
The R&D contracts were awarded in 1969, and the competitors went to work, both with the same handicap: incomplete information. Fearing that Kodak Corp. might enter the instant camera business, Polaroid wanted no leaks—so much so that it mentioned neither the new film nor the fact that at one point the camera was redesigned as an SLR—and kept the design teams from seeing a prototype of the camera. (Although TI’s then executive vice president, the now-retired Fred Bucy, saw a demonstration of the early, non-SLR SX-70 in 1969, he said nothing about it to the company’s engineers.) Said Peter Carcia, an engineer on the SX-70 project and still with Polaroid: “They had very little to work with”—only stacks of specifications.
When it contracted with Fairchild and TI to develop the electronics for the SX-70 camera, Polaroid Corp. provided this timing diagram along with 30 pages of other design specifications, reliability requirements, and test information. It indicates sequences of events for the four different modes of operation a fully automatic camera required. Table 1 indicates functions for taking photographs in ambient light, Table 2 covers flash operation, Table 3 calls out the sequence of events that is triggered when a new film pack is installed and its protective cover must be ejected, and Table 4 describes the operations that occur when a pack of film is used up.
Polaroid engineers recall that loads on the electronics were described simply as inductive, and that details of the battery supply were vague because a new battery was being concurrently designed.
“We didn’t tell them whether a load on the electronics was from a solenoid or a relay, just that it was an inductive load,” recalls Seymour Ellin, now a senior technical manager at Polaroid.
“Since we were making our own battery [designed concurrently], we couldn’t tell them what the battery supply would be,” said Carcia. “I would tell them ‘I want you to design a circuit, but I won’t tell you what the power source will be,’ and they would look at me strangely.”
Polaroid wanted no leaks—so much so that it mentioned neither the new film nor the fact that at one point the camera was redesigned as an SLR.
Even worse was the “Y” delay—which Polaroid engineers told IEEE Spectrum came from the “why” response given Fairchild and TI engineers whenever they questioned one specification: the short delay before starting the exposure, after the user pressed the button. This pause was to allow the mirror (which in an SLR camera reflects the image seen through the lens to the viewfinder) to stop vibrating after it snapped out of the way of the film to be exposed. But that was more than Polaroid wanted to divulge. The sources of the noise problem were left obscure, and its extent understated, said Clark Williams, then a TI design engineer. “That motor pulled 3 amps of current and put out a rich spectrum of noise that played havoc with our circuits,” he said. (He is now a design manager at Dallas Semiconductor Corp. in Dallas, Texas.)
The TI team, unable to base a breadboard on Polaroid’s diagrams alone, sent two engineers and several technicians to Cambridge to work in a little private room there. Whenever they needed to test their breadboard, they would hand it over to Polaroid engineers, who would carry it to another room and eventually report back that, say, a certain signal needed adjustment or a certain section did not function. The TI engineers would make a few adjustments, then the breadboard was carried off for another test. This to-and-fro-ing went on for six months, whereas, said Michael Callahan, a senior TI design engineer who is presently executive vice president of engineering at Crystal Semiconductors Corp. in Austin, Texas: “We could have done the work in two weeks if they had let us sign nondisclosure agreements.”
A preliminary round had disappointed both IC teams. In 1969, before Polaroid had firmed up many SX-70 details, it started both TI and Fairchild developing simple exposure control chips. This early effort, said Polaroid engineers, was also used to develop and test their working relationship with Fairchild. But the SX-70 project changed so much, particularly with its redefinition as an SLR camera, that Polaroid decided to start over. Callahan and Ken Buss, now a senior member of the technical staff at TI, recall a meeting in Dallas at which the TI engineers proudly demonstrated the working circuits—only to have Polaroid ignore them and announce its new requirements.
“That made our chips instantly obsolete,” Buss said. At Fairchild, too, enthusiasm flagged. Coincidentally, both companies soon after underwent a corporate restructuring, but whereas the changes at Fairchild benefited its SX-70 team, those at TI nearly cost it everything.
The TI designers, instead of working directly with Polaroid, were told to report to the Assembled Functions Group. Lacking either chip development or manufacturing facilities of its own, the Group contracted with the IC designers’ department to develop three chips—a photocell amplifier to determine the correct exposure, a chip to control the motor and handle dynamic braking, and a chip to handle timing, count the film used, and serve other functions—and with another department to manufacture the chips. The arrangement further filtered the already limited information from Polaroid.
Three different designs for the SX-70 exposure control electronics were produced. Fairchild Semiconductor Corp.’s version (top) went into cameras in 1972 and 1973—notice the polyimide film used to attach the ICs to the board. Texas Instruments Inc. produced its ceramic board (center) during 1972, then redesigned, and won the manufacturing contract away from Fairchild with a circuit board that used miniDIP IC packaging (bottom).
That left the Group itself with the job of designing the circuitry that would tie the ICs together. Its engineers used 13 discrete transistors, 17 laser-trimmed thick-film resistors, and a photodiode, intending to mount them on a printed-circuit board. Management instead mandated a ceramic substrate essentially because, said one TI design engineer, the Group reported to the same manager as TI’s Hybrid Thick-Film Group, which had excess capacity.
“We knew we couldn’t meet the cost goals with a ceramic substrate,” he said. The ceramic, the precious metal conductors, and the labor all cost too much for the substrate to serve as anything more than a prototype “to let us get all the circuitry in a small area.” And when the design grew from 3/4 square inch to 4 or 5 square inches (from 5 to 25 or 32 square centimeters), the engineer recalled, he and the other designers predicted major manufacturing problems and urged doing a more digital redesign with a printed-circuit board. But management “wouldn’t listen,” he said.
TI’s ceramic-based design did, however, perform to Polaroid’s specifications, and it went into production in late 1972. But it was indeed a nightmare. First, at $100 a unit, it was nowhere near the $5.75 cost goal. And manufacturing problems were tremendous, especially with the gigantic and therefore fragile ceramic substrate. For instance, said TI design engineer Norm Culp: “We had to take a chip, alloy it to a Kapton film carrier [a high temperature plastic foil], then wire bond the chip to the Kapton carrier, then encapsulate the chip. The Kapton film carriers were then tested individually, then reflowed onto the ceramic substrate.”
Yield was about 1 percent, and that one in 100 sometimes cracked on its way to Polaroid.
Moreover, said Culp, reflow-soldering chip carriers to the substrate caused microcracks in the ceramic, and for a while TI inspected every part for the flaws. Then one engineer realized that heating the entire substrate instead of just the part to be reflow-soldered would reduce the microcracks, which, however, showed up in other parts of the process. Yield was about 1 percent, and that one in 100 sometimes cracked on its way to Polaroid.
Polaroid did order several hundred of these ceramic modules to get the SX-70 to market. But it wasn’t at all happy with them. Said Ellin, “TI, essentially, failed to meet the cost objective.”
Meanwhile, engineers at Fairchild were also running into difficulties, but technical ones only. Early in the design process, Fairchild’s corporate restructuring moved the R&D engineers out of their isolated laboratory into operating divisions, making for better communication with manufacturing, which “resolved a lot of problems,” said Howard Murphy, a senior member of the Fairchild research staff and the project director for the SX-70 electronics.
"We designed a die that had around 20 flip-flops on it, probably a new high in IC complexity at that time.”—Howard Murphy, Fairchild
One design problem was high temperature. Murphy recalled that the heat of the heavy currents drawn by the motors and the solenoids affected the control logic circuitry, which then had to be redesigned to work at higher temperatures—the specifications indicated 40 °C. Another hurdle was the photo circuit. It had to time out after 20 seconds, so that pictures could be taken in dim light of about 0.06 candela per square foot (0.65 candela per square meter), although the circuit design team wasn’t fully aware of the reason for this at the time. The circuit also had to be very small and consume just a few milliamperes. “So we designed a die that had around 20 flip-flops on it, probably a new high in IC complexity at that time,” Murphy remembered.
Frank Perrino, a Fairchild product manager, first became involved in the SX-70 project in May 1971, when he oversaw its move into manufacturing. He recalled that the designers were then working on four chips—a driver for the motor and solenoids, a timing chip, and the photodiode and photodiode amplification chips that later became one bipolar CMOS IC. The dice were to be mounted directly on an irregularly shaped 1-by-4-inch ceramic substrate previously metalized on both sides with state-of-the-art lines and spaces.
The costs involved, however, ruled the approach out for production, Perrino told Spectrum. “The ceramic and chips all had to be perfect,” he said, and there was zero “probability of this happening.”
He concluded a printed-circuit board was a must, but how to mount the chips to it? Fairchild’s plastic DIPs were too large and costly for the job. He had, though, read a paper by General Electric engineers on beam tape packaging (BTP), a forerunner of what is now called tape automated bonding (TAB). After investigating BTP, he told Fairchild and Polaroid management, “If we don’t do it this way, it’s not worth doing.” Both agreed.
BTP employed reels of film with copper traces laminated on it around preexisting holes. Chips with bumps of solder on their pads were centered under the holes and bonded to the overhanging copper lead frames. Individual die/film modules were then encapsulated, tested, clipped off the reel, and soldered to the circuit board.
Perrino laid out the double-sided printed-circuit board at home on paper spread across his pool table. He then visited several companies that made polyimide interconnect film, contracted with 3M as a supplier, and persuaded West-Bond Inc. of Anaheim, Calif., to build equipment for attaching the dice to the reel of laminated film. The final circuit board held three IC dice and two flip-chip, thick-film, laser-trimmed resistors.
However, yields were not following the expected learning curve on two of the three ICs, the power transistors because of high doping levels and the timing chip because, said Perrino, of design errors. For example, Jim Feit, another engineer on the project, recalls a parasitic device affecting the flip-flops, which was fixed with the addition of a delay.
Still, though the parts were not cheap, costing Fairchild approximately $20 or $30 each, they were manufacturable.
The SX-70 was introduced in April 1972, in conjunction with the company’s annual stockholders’ meeting. A year earlier, Land had teased the stockholders by pulling a prototype SX-70 out of his pocket and waving it in the air. That was a working model, containing one of TI’s first successful ceramic circuit boards. But for this meeting, Polaroid needed 20 cameras, and John Burgarella, now retired from the company, had to make several trips to Texas to hand-carry enough working boards back to Cambridge. About a month earlier, Land had brought Fairchild engineers Perrino, Murphy, and Will Steffe to his Cambridge office and demonstrated the camera to them. “It was obviously a technological breakthrough,” recalled Perrino, which motivated them “to go back and make the thing work.”
Edwin Land showed the first working SX-70 camera at a stockholders’ meeting in 1971. It was only a prototype, and contained one of the first working ceramic circuit boards produced by Texas Instruments. A TI engineer had installed it the night before the meeting, working with a camera that was shrouded to prevent him from learning anything more about it than he already knew.
The introduction went off without a hitch. About a dozen scenes, from a poker game to a child’s birthday party, were enacted in a large warehouse, and well-known photographers were shooting them with the new cameras while Polaroid stockholders circulated and examined the pictures. Polaroid engineers were also circulating, with extra cameras in their pockets in case anything went wrong.
So Fairchild won a contract to manufacture the exposure control modules along with the motor circuits and the flash control circuits. The trade press touted their victory. According to a January 1973 Electronic News report, for instance, this contract, “believed to be the largest ever issued by a camera producer to an electronics supplier,” was worth $19 million, and was “considered by some semiconductor executives as an omen of considerable future business.”
Fairchild disbanded most of its design team, pleased with their success. But the manufacturing engineers pressed on, since the cost of the product had to be reduced by three-quarters or more to meet Polaroid’s price target, and contract negotiations were to be reopened for 1974. However, said Perrino, two of the chips in the exposure control module were still in trouble.
C. Lester Hogan, who had recently left Motorola Inc. to take over the Fairchild presidency, blames Fairchild’s then-outdated manufacturing facilities. He started a modernization, but he said, “there wasn’t a lot of extra cash,” and it was not complete until sometime in 1974.
Perrino blames the IC designs as well. “The design rules used in these chips were touch-and-go with the technology,” he told Spectrum. Polaroid’s Carcia agreed: ‘‘We were pushing the fundamental technology.” Redesigning the chips was talked about, but management did not mandate it.
The TI design team was also disbanded in 1972. Some left the company, some moved on to other projects. The failure, one design engineer told Spectrum, was a black mark that hurt careers.
At the highest level of TI, however, the book was not being closed. TI chairman Haggerty reportedly called his old friend Land and said, “We at TI don’t fail.” He assigned the project about $540,000 from his own budget, and told his managers to do whatever it would take to succeed. The code name Project Alpha emphasized the importance of the fresh start, and Haggerty put executive vice president Bucy in charge of it.
The failure, one design engineer [said], was a black mark that hurt careers.
As the original TI team had been disbanded, Bucy planned to assemble another one from the semiconductor division, and to ensure that this one would communicate directly with Polaroid and also have manufacturing responsibilities.
Dean Toombs, engineering director of the semiconductor group, held a series of meetings and developed a proposal for the redesign that was another break with TI’s first approach: it relied not on proven but on state-of-the-art IC technology and packaging. A circuit board only 1/64 inch thick was to hold up to four digital (not analog) ICs and eight discrete components at most. The chips would be surface mounted to the board in a miniDIP package, a method of volume assembly then new and risky but cheap. (It is now called SOT, which stands for Small Outline Transistors.)
The plan was approved by Bucy, and Henri Jarrat (then Eljarrat) selected to head the effort. At first Jarrat objected to the assignment, but gave way when told it was TI’s top priority. Given carte blanche to assemble a team from anywhere in the organization, he kept the group manageably small—only 18 people. They quickly partitioned the circuitry into three ICs and presented a six-month schedule for the redesign to Fred Bucy and Polaroid president William McCune.
Then Jarrat had his first meeting with Polaroid engineers. He told them he could only integrate the exposure control function into three components if they waived some of their specifications. He began going down his list and to each request the Polaroid engineers said no. So Jarrat stood up, threw his papers down, and said, he recalled, “Now I know why this project is going nowhere. This will never work, and I do not want to have my name attached to a failure.” He charged out of the room. Toombs backed Jarrat’s threat. “We had to get the customer under control,” he told Spectrum.
The ability to negotiate was in part also due to the availability of working cameras to study and the construction of a prototype on which to test breadboards of the chips—luxuries denied the first TI team.
After a brief adjournment, the meeting was reconvened and from then on Polaroid negotiated specifications. For example, the 20-second time out, for taking a picture in a dimly lit room, had made the signal from the photodiode impossibly low for the first design teams and this time around was cut to 10 seconds. “The big reason for our success was Jarrat’s success at convincing them to ease the specs,” said Clark Williams, a member of the second team.
The ability to negotiate was in part also due to the availability of working cameras to study and the construction of a prototype on which to test breadboards of the chips—luxuries denied the first TI team. And when the first group did raise questions out of concern for manufacturability, recalled Buss, the only TI engineer to work on both the design and the redesign efforts, they were told, “Well, your competition can do this.” And, in fact, Fairchild engineers don’t recall that the specifications were problematical.
TI began producing the Project Alpha boards in quantity in mid-1973.
With the redesign, TI quoted Polaroid a price of about $4.10 a unit—well below the $5.75 target. Said former Fairchild president Hogan: “At the time, it cost us $10. We really believed we could get it to $6, but when TI bombed the price down to two thirds of the target price, we just had to drop out.” As for a redesign, said Hogan, “we didn’t have the money to invest that way—we had to invest in the generic fixing of the factory.”
TI created a special camera division with Polaroid as its only customer. The company made about 850 000 units in 1974 and continued to produce the design until the SX-70 and the SX-70 Model 2 were discontinued in 1977. It also spun off a few innovations, including packaging for TI’s watch displays. And the engineers on the Project Alpha team were rewarded with then substantial raises of $100 to $500 a month.
West-Bond and 3M, companies Fairchild had recruited to manufacture packaging equipment and film tape, continued to profitably produce them for other companies.
Fairchild used the BTP packaging technology it developed for the SX-70 on its high-volume plastic DIP products at several manufacturing facilities. It also took its camera control technology overseas on a tour of Japanese camera manufacturers, but after several unsuccessful months gave up and closed down the production line for the exposure control module. It continued to manufacture flash control modules for Polaroid for another year, however. Within six months to a year of losing the exposure control contract, at least half the people who had worked on the project moved to other companies, Feit recalled.
Could the design have gone more smoothly? Certainly better communications between Polaroid and the two semiconductor companies and among different divisions within TI and Fairchild would have eliminated some of the rough spots.
From Polaroid’s standpoint, the information it handed out was as complete as it could be. After all, several parts of the camera system were being developed concurrently, so that the system specifications could not meanwhile be finalized. Also, said one Polaroid engineer, unfamiliarity with photography impaired the IC designers’ comprehension of the data they were given.
In the eyes of the TI and Fairchild engineers, useful information was withheld, and Polaroid engineers do admit a preoccupation with secrecy.
Still, in the eyes of the TI and Fairchild engineers, useful information was withheld, and Polaroid engineers do admit a preoccupation with secrecy due to concern over competition from Kodak. Perhaps being told that certain design issues had yet to be resolved or a detailed explanation of how an SLR functions would have elicited more creative engineering from the IC designers.
Be that as it may, the SX-70 was a brilliant success. Polaroid sold some three million units of the leather-covered Model 1 with its chrome-plated trim and the plastic-bodied Model 2. (Model 3, introduced in 1975, was not an SLR.) So while the design problems both TI and Fairchild endured triggered tense moments at all three companies, their solution opened up a huge new consumer market in electronics.
For details on the SX-70 circuitry, see “Behind the lens of the SX-70,” by Gerald Lapidus, IEEE Spectrum (December 1973, pp. 76-83).
Both Time and Life magazines featured the SX-70 camera on their covers in 1972, and discussed it in “Polaroid’s Big Gamble on Small Cameras” (Time, June 26, 1972, pp. 80-82) and “If you are able to state a problem, it can be solved” (Life, October 27, 1972, p. 48). To understand how the development of the SX-70 fit into Polaroid’s Jong history, read The Instant Image: Edwin Land and the Polaroid Experience by Mark Olshaker (Stein & Day, New York, 1978).
Frank Perrino’s version of tape automated bonding is described in U.S. Patent #3,868,724, “Multi-layer connecting structures for packaging semiconductor devices mounted on a flexible carrier,” dated Feb. 25, 1975.
Tekla S. Perry is a senior editor at IEEE Spectrum. Based in Palo Alto, Calif., she's been covering the people, companies, and technology that make Silicon Valley a special place for more than 40 years. An IEEE member, she holds a bachelor's degree in journalism from Michigan State University.
Gird yourself for muscle shirts that twitch
The UNSW team’s smart textile enables fabric reconfiguration that can produce shape-morphing structures, such as this butterfly and flower, which can move using hydraulics.
Recent advances in soft robotics have opened up possibilities for the construction of smart fibers and textiles that have a variety of mechanical, therapeutic, and wearable possibilities. These fabrics, when programmed to expand or contract through thermal, electric, fluid, or other stimuli, can produce motion, deformation, or force for different functions.
Engineers at the University of New South Wales (UNSW), Sydney, Australia, have developed a new class of fluid-driven smart textiles that can “shape-shift” into 3D structures. Despite recent advances in the development of active textiles, “they are either limited with slow response times due to the requirement of heating and cooling, or difficult to knit, braid, or weave in the case of fluid-driven textiles,” says Thanh Nho Do, senior lecturer at the UNSW’s Graduate School of Biomedical Engineering, who led the study.
To overcome these drawbacks, the UNSW team demonstrated a proof of concept of miniature, fast-responding artificial muscles made up of long, fluid-filled silicone tubes that can be manipulated through hydraulic pressure. The silicone tube is surrounded by an outer helical coil as a constraint layer to keep it from expanding like a balloon. Due to the constraint of the outer layer, only axial elongation is possible, giving muscle the ability to expand under increased hydraulic pressure or contract when pressure is decreased. Using this mechanism, says Do, they can program a wide range of motion by changing the hydraulic pressure.
“A unique feature of our soft muscles compared to others is that we can tune their generated force by varying the stretch ratio of the inner silicone tube at the time they are fabricated, which provides high flexibility for use in specific applications,” Do says.
The researchers used a simple, low-cost fabrication technique, in which a long, thin silicone tube is directly inserted into a hollow microcoil to produce the artificial muscles, with a diameter ranging from a few hundred micrometers to several millimeters. “With this method, we could mass-produce soft artificial muscles at any scale and size—diameter could be down to 0.5 millimeters, and length at least 5 meters,” Do says.
The filament structure of the muscles allows them to be stored in spools and cut to meet specific length requirements. The team used two methods to create smart fibers from the artificial muscles. One was using them as active yarns to braid, weave, or knit into active fabrics using traditional textile-making technologies. The other was by integrating them directly into conventional, passive fabrics.
The combination of hydraulic pressure, fast response times, light weight, small size, and high flexibility makes the UNSW’s smart textiles versatile and programmable. According to Do, the expansion and contraction of their active fabrics is similar to those of human muscle fibers.
This versatility opens up potential applications in soft robotics, including shape-shifting structures, biomimicking soft robots, locomotion robots, and smart garments. There are possibilities for use as medical/therapeutic wearables, as assistive devices for those needing help with movement, and as soft robots to aid the rescue and recovery of people trapped in confined spaces.
Although these artificial muscles are still a proof of concept, Do is optimistic about commercialization in the near future. “We have a Patent Cooperation Treaty application around these technologies,” he says. “We are also working on clinical validation of our technology in collaborations with local clinicians, including smart compression garments, wearable assistive devices, and soft haptic interfaces.”
Meanwhile, the research team continues to work on improvements. “We have currently achieved an outer diameter of 0.5 mm, which we believe is still large compared to the human muscle fibers,” says Do. “[So] one of the main challenges of our technology is how to scale the muscle to a smaller size, let’s say less than 0.1 mm in diameter.”
Another challenge, he adds, relates to the hydraulic source of power, which requires electric wires to connect and drive the muscles. “Our team is working on the integration of a new soft, miniature pump and wireless communication modules that will enable untethered driving systems to make it a smaller and more compact device.”
Analytical modeling for bending actuators is yet another area of improvement. Concomitant studies to demonstrate the feasibility of machine-made smart textiles and washable smart textiles in the smart garment industry are also necessary, the researchers say, as are further studies regarding incorporating functional components into smart textiles to provide additional benefits.
The Manchester “Baby” was the first electronic digital computer to store a program
Joanna Goodrich is the assistant editor of The Institute, covering the work and accomplishments of IEEE members and IEEE and technology-related events. She has a master's degree in health communications from Rutgers University, in New Brunswick, N.J.
A replica of the Manchester “Baby” computer at the Museum of Science and Industry in Chicago.
Whether you’re streaming a movie on Netflix, playing a video game, or just looking at digital photos, your computer is regularly dipping into its memory for instructions. Without random-access memory, a computer today can’t even boot up.
Over the years, memory has been made up of vacuum tubes, glass tubes filled with mercury and, most recently, semiconductors.
But the first computers didn’t have any reprogrammable memory at all. Until the late 1940s, every time a machine needed to change tasks, it had to be physically reprogrammed and rewired, according to the Science and Industry Museum in Manchester, England.
The first electronic digital computer capable of storing instructions and data in a read/write memory was the Manchester Small Scale Experimental Machine, known as the Manchester “Baby.” It successfully ran a program from memory in June 1948.
Computing pioneers Frederic C. Williams, Tom Kilburn, and Geoff Tootill developed and built the machine and its storage system—the Williams-Kilburn tube—at the University of Manchester.
“The Baby was very limited in what it could do, but it was the first-ever real-life demonstration of electronic stored-program computing, the fast and flexible approach used in nearly all computers today,” said James Sumner, a lecturer on the history of technology at the University of Manchester, in an interview with theManchester Evening News.
The IEEE commemorated Baby as an IEEE Milestone during a ceremony held on 21 June at the university.
How Baby Came to Remember
After World War II, research groups around the world began investigating ways to build computers that could perform multiple tasks from memory. One such researcher was British engineer F.C. Williams, a radar pioneer who worked at the Telecommunications Research Establishment (TRE), in Malvern, England.
Williams had an impressive background in radar systems and electronics research. He helped develop the “identification: friend or foe” system, which used radar pulses to distinguish Allied aircraft during the war.
Because of his expertise, in 1945 the TRE tasked Williams with editing and contributing content to a series of books on radar techniques. As part of his research, he traveled to Bell Labs in Murray Hill, N.J., to learn about work being done to remove ground echoes from the radar traces on CRTs. Williams came up with the idea of using two CRTs, and storing the radar trace by passing it back and forth between the two. Williams returned to the TRE and began to investigate the idea, realizing that the approach also could be used to store digital data, with just one CRT. Kilburn, a scientific officer at the TRE, joined Williams in his research.
“The Baby was the first-ever real-life demonstration of electronic stored-program computing, and the fast and flexible approach is used in nearly all computers today.”
A CRT uses an electron gun to send a focused beam of electrons toward a phosphor-laden screen. The phosphors glow where the beam strikes; the glow eventually fades until struck again by the electron beam. To store digital data, Williams and Kilburn used a more powerful electron beam. When it hit the screen, it knocked a few electrons aside, briefly creating a positively charged spot surrounded by a negative halo. Reading the data involved writing to each data spot on that plate and decoding the pattern of current generated in a nearby metal plate—which would depend on whether there was something written at that spot previously.
It turned out that the electron charges leaked away over time (just as phosphors on a TV screen fade) and didn’t allow the tube to keep storing data, according to an entry about the Milestone on the Engineering and Technology History Wiki. To maintain the charge, the electron beam had to repeatedly read the data stored on the phosphor and regenerate the associated charge pattern. Such refreshing is also used in the DRAM present in today’s computers.
In 1946, the men demonstrated a device that could store 1 bit. It is now called the Williams-Kilburn tube; sometimes just the Williams tube.
Also in 1946, Williams joined the University of Manchester as chair of its electrotechnology department. The TRE temporarily assigned Kilburn to work with him there, and the two continued their research at the university’s Computing Machine Laboratory. A year later Williams recruited computer scientist Tootill to join the team. And in 1947 they successfully stored 2,048 bits using a Williams-Kilburn tube.
To test the reliability of the Williams-Kilburn tube, in 1948 Tilburn and Tootill, with guidance from Computing Machine Laboratory founder Max Newman and computer scientist Alan Turing, built a small-scale experimental machine. It took them six months, using surplus parts from WWII-era code-breaking machines. And the Manchester Baby was born.
The Baby took up an entire room in the laboratory building. It was 5 meters long, 2 meters tall, and weighed almost a tonne. The computer consisted of metal racks, hundreds of valves and vacuum tubes, and a panel of vertically mounted hand-operated switches. Users entered programs into memory, bit by bit, via the switches, and read the output directly off the face of the Williams-Kilburn tube.
On 21 June 1948, Baby ran its first program. Written by Kilburn to find the highest factor of an integer, it consisted of 17 instructions. The machine ran through 3.5 million calculations in 53 minutes before getting the correct answer.
By 1953, 17 pioneering computer design groups worldwide had adopted the Williams-Kilburn RAM technology.
Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world. The IEEE Manchester Section sponsored the nomination for the Baby. The Baby Milestone plaque, which is to be displayed outside on the Coupland 1 building at the University of Manchester, reads:
“At this site on 21 June 1948 the ‘Baby’ became the first computer to execute a program stored in addressable read-write electronic memory. ‘Baby’ validated Williams-Kilburn tube random-access memories, later widely used, and led to the 1949 Manchester Mark I which pioneered index registers. In February 1951, Ferranti Ltd.’s commercial derivative became the first electronic computer marketed as a standard product delivered to a customer.”