For a hint at what Toyota Motor Corp. sees when it peers into the future, have a look at the TAO-Light II, a sleek new addition to its lineup with a top speed of a littlemore than six kilometers per hour.

That may be slow, but the TAO-Light II isn't a car. It is a wheelchair made from car parts, developed by Aisin Seiki Co., a Toyota supplier of transmissions and drive trains. The TAO is among a slew of new products from Toyota and its hundreds of suppliers that tap the market for elderly Japanese and the families who care for them.

Engineers are using automobile technologies to make products designed for the aging -- turning, for example, shock-absorber systems into hydraulic home-use elevators. Toyota's suppliers of rubbers and plastics are making orthopedic mattresses and special exercise mats for fragile bodies. Toyota Home, the company's decades-old prefabricated-housing business, is offering kitchen cabinets that slide down on rails to wheelchair height.

Cars are a crucial part of the push, too. In Japan, Toyota offers 37 different Welcabs -- specially converted models with options like swivel seats and wheel-chair ramps to grant easy access to infirm passengers. "This is a priority for all the companies of the Toyota group," says Hideyuki Iwata, an executive chief engineer.

According to government projections, a quarter of Japan's population will be 65 years or older by 2015. By the year 2050, 35 percent will be over 65. Japanese families are having fewer children, so the number of youth is shrinking, and the overall population will peak next year at 128 million. Meanwhile, Japan's average life expectancy of 82 years is one of the highest in the world. And though Japan is aging faster than other countries, the trend is global: The United Nations forecasts that the world population of people 65 and over, currently at 472 million, will reach 598 million by 2015 and 823 million by 2025.

Toyota's efforts amount to a case study on maneuvering around a tricky marketing challenge: How does a company grow sales as the population begins to age so rapidly? Although executives won't say how much Toyota has invested in products for the graying market, the company is clearly intent on turning Japan's stark demographic trends into a growth opportunity.

Few doubt the potential of the burgeoning elderly market. Expenditures for medical care and welfare services are expected to reach $650 billion by 2010, more than a 25 percent increase over 2002, according to Japanese government figures. What's more, since 2000, Japan has started to offer subsidies for products like wheelchairs and reclining beds in an effort to encourage more families to take care of the elderly at home and cut down on fees for nursing homes.

Across Japan, other companies are focusing more on older consumers. Matsushita Electric Industrial Co., best known for such electronics brands as Panasonic and Quasar, has a business unit devoted to opportunities in this market, offering medical equipment, consulting services and nursing homes. Sanyo Electric Co. another electronics company, is also making a number of products. One is a $45,000 washing machine for human beings in which elderly patients sit, immersed up to their heads, while the device runs through its cycles of soak, wash and rinse.

Tokyo's Watami Co., which runs a chain of 500 bars across Japan serving sake and fish, decided to diversify by acquiring a chain of nursing homes. It is also branching out into geriatric foods and other health-related services. "The aging society is coming," says spokesman Naohiro Nakagawa. "The market for pubs is going to shrink."

Toyota has a long tradition of applying core technology to diverse fields, dating back to 1937 when founder Sakichi Toyoda spun the car-making business out of his loom-manufacturing operation. Ever since, Toyota engineers have tried to be equally resourceful, translating their expertise to fields ranging from communications to bioengineering.

Toyota began designing cars with the elderly in mind back in the early 1990s, as part of its push toward making cars more accessible to customers of all ages. But the elderly market became a priority after a tragedy in 1995, when Tatsuro Toyoda, the grandson of the company's founder, who is currently 76, had a stroke and stepped down as president. People familiar with the matter say the chairman at the time, Shoichiro Toyoda, Tatsuro's older brother, got a close look at what it was like to care for an elderly family member with physical limitations.

Shoichiro, who is now 80 years old, concluded Toyota had a responsibility to serve the aged. He began encouraging executives to devote resources to study the issue and explore possible product lines. At Toyota, even a hint from a member of the founding family, notably one acting as chairman, was as good as a command. The Toyodas "remain a powerful force drawing the group together," says Mr. Iwata, the Toyota engineer. "When somebody like (Shoichiro) says the company should do something, he definitely is going to get a response."

Across the Toyota group, companies began thinking up ways to apply their expertise and innovations to the market of elderly people. Toyota Auto Body Co., a major parts supplier, develops electric motors that open and close curtains in the back of minivans. It tried marketing them for blinds in conference rooms but found there was little demand. The company reworked the product into motors for doors that slide open with a gentle nudge -- useful for those in wheelchairs or walkers.

These motors can also be used to open curtain railings by remote-control switch -- a help for somebody confined to bed. "We now see the home market as the most promising," says Toshiaki Onoyama, of Toyota Auto Body's linear-motors department.

In 2001, representatives from a number of big Toyota suppliers began coordinating their marketing strategies and decided to market their goods jointly at trade fairs, using Toyota's homebuilding subsidiary, Toyota Home, as a sales channel. The collection is on display and open to the public at a model home exhibition near Toyota's headquarters in Nagoya.

The building has access for wheelchairs (developed by Aisin), which allows them to move from a car in the driveway to a small metal lift (by Toyota Auto Body) to an outdoor porch. Special systems (by Miwa Lock Co.) use car-key technology to open doors automatically when detecting keys in handbags or pockets. The kitchen has cabinets that can be lowered to the level of a user in a wheelchair by hitting a thin rail along the bottom (by Denso Corp., a major supplier of electronics and other parts) and an elevator uses hydraulics (by Toyota Auto Body). Upstairs, an electric reclining bed (Aisin) has mattresses designed with high-end materials (Toyoda Gosei Co., a rubber and plastics supplier) that are gentle on bones of the elderly.

Though cutting-edge, the various projects still represent something of a gamble for Toyota. One problem: Products tailored too closely for the elderly risk alienating customers, both old and young.

Indeed, the company's prefab home exhibit is called Atolis Park. Atolis stands for All Toyota Life System, a name chosen carefully to avoid sounding like it was designed for old people.

"Nobody wants to think of themselves as old," concedes Shiro Ina, a manager at Toyota's housing subsidiary.

Yet a failure to acknowledge the needs of mature customers -- from the gadgets in their homes to the cars they drive -- might mean ceding market share to any rival who does.

General Motors Corp. and Ford Motor Co. have both begun adjusting designs on standard models with older folks in mind. But for the most part, cars with wheelchair access or swivel seats are largely handled by specialists in the after-sales market. Nissan Motor Co. has 26 models with options for the elderly, while Honda Motor Co. has 10 -- though both lag behind Toyota's 37 models.

Another big challenge for Toyota is to turn these products, whose market is still tiny, into profitable businesses. In its core area of autos, engineers are trying to refine the production process so they can cut costs enough to eke out profit even with a relatively small market. Japan's market for cars designed for the elderly currently remains only 40,000 vehicles sold per year. While that figure is up from 5,000 vehicles 10 years ago, it is a small fraction of the 5.9 million new cars sold each year.

Toyota can, however, claim the advantage of foresight. Since the 1980s, the company has supplied Welcabs to medical facilities for the aging or disabled. For years, the market for such vehicles was considered a niche. But since 2000, when regulators began encouraging home care, Toyota has been eyeing the mainstream. Today it offers Welcab versions of models including not just minivans, but also sedans, economy-class cars and sport-utility vehicles.

Until now, specialists have made Welcab cars by taking finished vehicles and retrofitting them with special seats, railings or ramps for wheelchairs. This inefficient, expensive process made sense in a small market with a handful of products. But Toyota, aiming at the high volume market, began this year producing a Welcab right on the assembly line.

The first car to be produced this way is the Ractis, a small, four-seat minivan that Toyota introduced to Japan in October. At Toyota's Takaoka plant outside Nagoya, one of Toyota's most efficient production facilities, plant manager Yasumitsu Morita recently stood next to the assembly line where a new Ractis was made every 60 seconds. He pointed down the line at a gray minivan slowly moving forward. "That one is different," he said, his voice rising above the welding and drilling.

The gray car was a Welcab version of the Ractis, which unlike the other cars on the line, has a scoop-shaped back end, allowing for the installation of a wheelchair ramp that folds out. As the car moved by, Mr. Morita pointed underneath to more unique parts, including two hydraulic lifts that will allow the back end of the car to be lowered to the ground for easier access for a walker or wheelchair. The next car that came along was a normal Ractis, with none of the 100 special parts needed to make the Welcab version.

Mr. Morita noted that Toyota's flexible line makes it possible to produce the Welcab as easily as it changes color from model to model, allowing the company to adjust easily to the level of demand. Right now, there is only enough demand in Japan for the Takaoka plant to make one Ractis every hour. But as the population ages, Toyota will be ready if there's increased demand. "We are flexible enough to switch back and forth as much as needed," Mr. Morita said. Although its Welcams are still unprofitable, Toyota expects the line to be in the black within a year or two.

Meanwhile, Toyota dealers are holding seminars and advertising these cars aggressively. The Toyota group is participating in "home care" conventions now being held in cities across Japan, at which Toyota exhibits Welcabs amid other booths showing adult diapers and walkers.

And Toyota engineers continue to tweak their lineup of products targeting the elderly. These include an upgraded version of the Tao-Light II wheelchair. Aisin, working with electronics company Fujitsu Ltd., has developed the TAO Aicle, a new electric wheelchair that can be programmed to carry the driver to destinations on auto pilot mode.

Says Mr. Iwata, the Toyota engineer: "We don't see any other global car maker putting the effort into this that we are."