It's no secret robot sales are booming in the U.S., but a visit to the recent International Robots and Vision Automation show in Detroit reveals that robot manufacturing is quietly moving here.

Thanks to strong U.S. demand, the trend toward supplier globalization and the musclebound yen, some Japan-based roboteers are shifting production to the States.

Kawasaki Robotics Inc. says it has been building robots in a factory in Lincoln, NE, for the past 12 months and has shipped almost 1,000 locally-made units to the U.S. auto industry.

At lunch with a few reporters, Philip V. Monnin, president of Motoman Inc., a wholly-owned subsidiary of Japan-based Yaskawa Electric Corp., casually mentions a new venture: Stillwater Technologies -- a Motoman supplier -- and his company are building a $20 million facility in Troy, OH, to manufacture robots and components beginning next year. Insiders say more Japanese robot producers are likely to follow before long.

Motoman had estimated sales of $50 million in 1994. Kawasaki is best known in the U.S. as a maker of motorcycles and jet skis. It builds those in the same plant as the robots. "It's a real interesting plant tour," says a company spokesman.

But in Detroit, Kawasaki Robotics is well-known. It has sold more than 4,000 robots in the U.S. in the past 25 years, mostly to automakers. The company recently doubled the size of its North American headquarters and moved from Farmington Hills to Wixom, MI.

But in a good example of how tricky the economics of globalization sometimes can be, Japan-based Fanuc Ltd. -- one of the world's largest robot producers -- is not buying a ticket on this particular train. The reason: Its costs are different from its competitors.

Although Fanuc is constantly evaluating the situation, Eric Mittelstadt, president of its U.S. subsidiary, Fanuc Robotics North America Inc. (FRNA), says there are no plans to increase U.S. production. Fanuc manufactures a small number of painting robots in Auburn Hills, MI, but 70% to 75% of its North American revenues -- "way over $100 million" -- come from customizing robots and software for specific applications, not selling robot arms.

He adds that even though manufacturing in expensive Japan, Fanuc is the world's low-cost robot producer thanks to big volumes and highly automated processes. Robot arms are machined in a completely automated "lights out" factory in Japan that can produce 1,000 units per month, Mr. Mittelstadt says. Computer controllers, a key element in the overall price of a robot, also are less costly because Fanuc is the world's largest supplier of highvolume computer numerical controllers, which are quite similar to robot controls.

Fanuc is buying raw materials, mostly imported, with an appreciated yen, which further reduces its costs. "It may make sense for soem of our competitors to shift production to the U.S., but not for us," Mr. Mittelstadt sums up.

U.S. robot production all but disappeared during the late 1980s as demand sagged and North American robot-makers went out of business or were swallowed up by Japanese or European multinationals.

But since 1991, fueled by the recovery of the North American auto industry -- more than 50% of the market -- sales of robots have been soaring.

The Robotic Industries Association (RIA), the industry's trade group, reports shipments and new orders are well above last year's record levels.

Even so, officials at RIA and robotcompany executives hardly sound giddy as they nervously eye declining car sales and growing vehicle inventories, and are looking hopefully to nonautomotive markets. They remember the 1980s all too well.

Ten years ago, many experts predicted "robots that can see" using computer machinevision systems would revolutionize the way cars are manufactured. When they didn't live up to expectations, they were abandoned. Since 1991, robot use has rebounded in the auto industry. But vision systems have enjoyed much greater acceptance outside automotive, mostly in the semiconductor and electronics industries, which combined account for 50% of total machine-vision sales. That industry's North American sales jumped 19% in 1994, to $888 million, and could reach $1.5 billion by 1999, based on a study by the Automated Imaging Association (AIA).

Independent manufacturing engineering firms have helped automakers build and retool plants since the industry began, but now four of them have set aside their competitive differences to form the International Association of Manufacturing Engineering Firms (IAMEF). The group's mission is to promote development of quality-improvement techniques "throughout the manufacturing community." IAMEF also will work to improve the efficiency of manufacturing overall through defined performance standards, member education and continuing R&D.