Section: TECHNOLOGY

Spar Aerospace has breathed new intelligent life into its space arm. The result is a limb strong enough to lift tonnes of metal; sensitive enough to avoid crushing delicate electronic units.

APPEARANCES ARE DECEIVING. Like its Canadarm predecessor, the next generation of space arms suggests the general ungainliness of a praying mantis. But the new arms are not really like the Canadarm at all. Thanks to quantum leaps in robotics, vision systems and artificial intelligence, this next wave of arms is "smart." The new limbs "see," "feel" and "react," exercising motor skills sophisticated enough to pick up sensitive electronic units without crushing them, and using tools to replace bolts without stripping the threads. Like their insect look-alikes, these arms move--one of them will actually "inch" end over end around the space station that it will help to build.

Heady stuff--and it has great implications for astronauts and the arms' developer, Spar Aerospace Ltd. At the company's lab in Toronto, a nearly full-size prototype of its two-armed robot hangs from a gantry, where Spar technicians run constant tests to build in a revolutionary new dexterity. Although not up to the task of building space stations just yet, the new arms clearly soar in a higher orbit than the original. Astronauts operate the Canadarm manually, for instance, navigating it by means of a camera. But in the same way you grope for an alarm clock in the dark, it takes time to hit the target. Relying on its own computerized brain, the new arms can perform the same task much more efficiently. It has; you could say, an immensely powerful chip on its shoulder.

Spar engineer Scott McClure demonstrates: he switches on the arm's sensing systems and instructs it to lift a cubic metre-sized metal box and lower it onto a frame where it will trigger special latches. Camera images feed into the arm's vision system and force sensors tell its computer whether the box is straight. In a single smooth movement, the arm directs the box into place. An image on the computer monitor shows it to be slightly skewed, triggering latches on one side first. The arm swiftly corrects the angle and eases the box into place. Elapsed time: 30 seconds--versus more than 15 minutes a manually operated arm needs to perform the same operation. In four short years, astronauts will start building the orbiting US space station Freedom, using the same process.

The new Spar space arms come a decade after the space shuttle Columbia deployed the company's first Canadarm. Spar engineers are now completing the prototypes: a single 17-metre arm and a six-metre two-armed robot similar to the model in McClure's lab. They're more versatile,; more maneuverable, easier to update with new technology--but most of all, they can do some tasks more efficiently and with less risk than an astronaut could. "Canadarm was more like a crane," says Jim Middleton, who headed Spar's systems engineering group for the Canadarm program and now, at age 50, leads the latest robotic arms project. "The new arms can do much more humanlike tasks."

The developments promise considerable spin-off potential for Spar and for innovators in other terrestrial industries. "These robot technologies can also be used in hazardous environments such as waste handling, nuclear power plants, mining and under the oceans," says Middleton. Their attraction is obvious: "[Robots] don't get sick and they don't get bored." If Spar doesn't want to use the technology itself, it may share the new arms' technology with other Canadian industries, particularly those that can find ground-based applications.

Spar is building the advanced space arms as prime contractor on the Canadian Space Agency's (CSA) $1.2-billion project to supply a mobile servicing system for the space station. Half the work will be farmed out to a nationwide team of contractors ranging from R&D specialists MacDonald Dettwiler & Associates in Richmond, BC, to IMP Group Ltd. in Halifax. The first of what NASA expects will be 20 construction flights to build the space station leaves in the second half of 1995. The single Spar arm is scheduled to be deployed--by shuttle astronauts using the original Canadarm--in March, 1996, on the third flight. The two-armed robot goes up in March, 1997. The first noble occupation of these thinking limbs will be as space-age construction workers.

After the robotic arms help build the station, they will stay on as Freedom's outside maintenance workers, changing worn-out electronics units, cleaning and lubricating surfaces, grabbing onto docking orbiters, installing or assembling payloads and even chauffering astronauts around the outside of the station. If the space station has them, the Spar arms will probably do windows.

Back on earth, the new arms are providing some of the lift to Spar's improved financial results. Revenues jumped 50% to $333 million during the first nine months of 1991, but earnings rocketed to $6.8 million, more than quadrupling 1990 figures over the same period. The space arms project gets much of the credit for the gain, although the company won't reveal the percentage of revenues attributable to the space station system. So far, the CSA has agreed to pay Spar $195 million for the first phase, which is supposed to end Mar. 31. After a final design review in jury, when NASA and CSA scientists go over the detailed engineering blueprints, manufacturing of the actual flight equipment begins. How much the CSA pays for this part of the project, which runs until December, 1996, has not yet been announced.

Middleton says it's difficult to quantify Spar's ultimate payoff in this new-age arms deal. Even though there are no competing programs to buy robotic space station arms--the European and Japanese space programs are sharing alongside the CSA in the US project--Spar will be trying to develop spin-offs from new robotic-arm technology. "The object isn't to get into production," says Middleton. "It's to sell variant systems" of different sizes and capabilities.

One opportunity will be NASA's project to return to the moon, scheduled for sometime after the year 2000. A lunar module, for example, could use smart arms to help gather samples, conduct experiments in the lunar environment or do external maintenance. But that all depends on flawless execution on the space station. So far, Middleton says, Spar has added 150 new employees to the project over the past three years, bringing its space arm workforce to 450 managers, engineers and manufacturing employees in Toronto and Montreal.

Spar has good reason to pursue this kind of new-world-order arms business. After building the first Canadarm for $100 million, Spar sold NASA three others for more than $200 million, including follow-on work. Since 1981, the Canadarm project has accounted for a healthy pelt of its revenues. Even now, as Japan prepares for its 1998 shuttle launch,Spar still has a customer for Canadarm hardware. "We are modifying the present Canadarm," confirms Middleton. "The knowledge and expertise of the Canadarm program continue to pay off on other programs." Company spokesperson Gail Macnaughton says Spar expects similar spin-off returns from the smart space station arms: "We have the example of Canadarm to back it up."

But the arms' contribution to Spar's financial picture will probably pale beside their public relations value. The Canadarm, no shrinking violet itself, is fixed to the shuttle at the shoulder. But the new single-arm robot will be able to attach itself at either end to grapple fixtures all over the space station, allowing it to "inch-worm" end over end around the structure. The two-armed robot is mobile, too. The single arm can pick it up and move it to any of the grapple fixtures, or the two-armed robot can work while attached to the end of the single arm, giving it extra reach. The entire servicing system, of which the robotic arms are the major part, can be moved around the space station along a track. The arm will provide power or data through a port on each end. Once attached to a load, it will handle up to 116,000 kg, more than 25 times the weight of the whole servicing system. Suffice it to say, the arms will love a camera.

A few technological hurdles still stand in the way of a clean liftoff: In McClure's lab, Spar engineers are working especially hard on refining the software that gives the robot its brainlike ability to move two arms at once without them running into each another. "It uses one arm to hold onto something while the other arm does the manipulating," says Middleton. "The bilizer is important because you need to remove any wiggling." Working closely with NASA specialists, the Spar scientists are also perfecting the artificial vision and force-sensing systems. "There are many meetings," says Middleton of NASA's interest in the program. "Weekly, monthly, quarterly design meetings--there's continual interaction."

Ground testing of the single-arm robot begins in late 1993 or early 1994. "That's when we start assembling," says Middleton. "It takes about a year to assemble." The prototype hardware is already 75% complete, says Karl Doetsch, CSA director general for the space station program. As each new assembly is finished, it is sent to the CSA's David Florida Laboratory in Ottawa's west end, one of North America's most advanced space--simulation testing centres. In a thermal vacuum chamber, every joint and system passes muster at the extreme temperatures they will face in space-as high as 150 Celsius and as low as -150 Celsius. Another test subjects them to the intense vibrations that occur when the solid rockets ignite and burn during launch. So far, Doetsch says, about 30% to 40% of the systems' design drawings are complete, and manufacturing of some of the hardware has started.

Past experience is helping Spar create new business for the future. An important lesson the Canadarm demonstrated was how quickly new technology can be out-paced. "The Canadarm was designed in the early '70s," says Middleton, "so the technologies were relatively archaic compared with what's available now." Engineers had a head start, for example, when it came to designing a joint that wouldn't fail or cop, damaging the side of the space station or whatever payload the arm is holding. But now, the joints' circuitry is smaller and more efficient, allowing the arm to be stronger. And with the addition of vision, sensory and expert systems, the new arms make the Canadarm look primitive. Even so, says Middleton, it won't take long for better technology to outdate today's. "The technologies we're using now are mid- to late '80s."

To get around the problem, Spar designed its arms in modules that can be replaced as it develops better components. The space arms have to last 30 years, says Middleton, "And we had to be sure we can evolve technologies and add them on, without having to scrap the original system."

Thirty years of updating is a lot of work. But if the dramatic difference between the 10-year-old Canadarm and the new generation of space arms is any indication of the future pace of robotic-arm evolution, Spar's job will be an armful.

PHOTO (COLOR): The smart version: it sees, it feels, it reacts

PHOTO (COLOR): The not-so-smart version: designed in '70s

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By John Southerst