At the Meiji University lab in a Tokyo suburb, engineering students are wiring a rubbery robot face to simulate six basic expressions: anger, fear, sadness, happiness, surprise and disgust.

Hooked up to a database of words clustered by association, the robot Kansei (sensibility) responds to "war" by quivering in what looks like disgust and fear. It hears "love" and it smiles.

"To live among people, robots need to handle complex social tasks," said project leader Junichi Takeno. "Robots will need to work with emotions, to understand and eventually feel them."

Robots still are nowhere close to matching human emotional complexity, but Japan is perhaps the closest to what was once the stuff of science fiction: creating intelligent robots that can live side by side with humans and interact socially with them.

The presence of robots in Japanese factories is already a given, so much so that they are sometimes welcomed on their first day at work with Shinto ceremonies. Robots make sushi, plant rice and tend paddies.

There are robots serving as receptionists, vacuuming office corridors, spoon-feeding the elderly. They serve tea, greet company guests and chatter away at public technology displays. Now startups are marching out robotic home helpers.

They aren't all humanoid. The Paro is a furry robot seal fitted with sensors beneath its fur and whiskers, designed to comfort the lonely, opening and closing its eyes and moving its flippers.

For Japan, the robotics revolution is an imperative. With more than a fifth of the population 65 or older, the country is banking on robots to replenish the workforce and care for the elderly.

In recent years, the government has funded a plethora of robotics-related efforts, including some ¥4.6 billion for the first phase of a humanoid project, and ¥1.1 billion a year between 2006 and 2010 to develop key technologies.

The government estimates the industry could surge from about ¥558 billion in 2006 to ¥3 trillion in 2010 and nearly ¥7.5 trillion by 2025.

Besides financial and technological power, the robot wave is favored by the Japanese mind-set as well.

Robots have long been portrayed as friendly helpers in popular culture, a far cry from the often rebellious, violent machines that inhabit Western science fiction.

Japanese are also more accepting of robots because the Shinto often blurs the boundaries between the animate and inanimate, experts say. To the Japanese, the idea of a humanoid robot with feelings doesn't feel as creepy — or as threatening — as it might in other cultures.

Still Japan faces a vast challenge in making the leap — commercially and culturally — from toys, gimmicks and the experimental robots churned out by labs like Takeno's to full-blown human replacements that ordinary people can afford and use safely.

"People are still asking whether people really want robots running around their homes, and folding their clothes," said Damian Thong, senior technology analyst at Macquarie Bank in Tokyo.

"But then again, Japan's the only country in the world where everyone has an electric toilet," he said. "We could be looking at a robotics revolution."

That revolution has been quietly going on.

Japan is already an industrial robot powerhouse. Over 370,000 robots worked at factories nationwide in 2005, about 40 percent of the global total and 32 robots for every 1,000 Japanese manufacturing employees, according to a recent report by Macquarie, which had no numbers from subsequent years.

"The cost of machinery is going down, while labor costs are rising," said Eimei Onaga, CEO of Innovation Matrix Inc., which distributes Japanese robotics technology in the U.S. "Soon, robots could even replace low-cost workers at small firms, greatly boosting productivity."

That's just what the government has been counting on. A 2007 national technology road map by the Economy, Trade and Industry Ministry calls for 1 million industrial robots operating nationwide by 2025.

A single robot can replace about 10 employees, the road map assumes — meaning Japan's future million-robot army of workers could take the place of 10 million humans. That's about 15 percent of the current workforce.

"Robots are the cornerstone of Japan's international competitiveness," Shunichi Uchiyama, the trade ministry's chief of manufacturing industry policy, said at a recent seminar. "We expect robotics technology to enter even more sectors going forward."

Meanwhile, localities looking to boost regional industry clusters have seized on robotics technology to spur advances in other fields.

The logical next step is robots in everyday life.

At a hospital in Aizu Wakamatsu, Fukushima Prefecture, a child-size white and blue robot wheels across the floor, guiding patients to and from the outpatients' surgery area.

The robot, made by startup Tmsk, sports perky catlike ears, recites simple greetings, and uses sensors to detect and warn people in the way. It helpfully prints out maps of the hospital, and even checks the state of patients' arteries.

Aizu Chuo Hospital spent about some ¥60 million installing three of the robots in its waiting rooms to test patients' reactions. The response has been overwhelmingly positive, spokesman Naoya Narita said.

"We feel this is a good division of labor. Robots won't ever become doctors, but they can be guides and receptionists," Narita said.

Still, the wheeled machines hadn't won over all seniors crowding the hospital waiting room on a weekday morning.

"It just told us to get out of the way!" huffed Hiroshi Asami, 81, in a wheelchair. "It's a robot. It's the one who should get out my way. I prefer dealing with real people."