Companies at this week's International Home Care and Rehabilitation Exhibition in Tokyo are showcasing incontinence devices that combine a diaper with a personal bidet, removing waste before cleaning and then drying the wearer as they sleep, hoping to win a share of the nation's burgeoning senior care market.

One of the devices is a U-shaped cup that fits between the wearer's legs and contains a sensor that activates a suction mechanism when triggered.

Waste is moved rapidly away from the body before a bidet cleans with a spray and then dries with a blower. The cup is connected to a duct that moves the waste into a tank. "This machine is intended to ease the burden for caregivers, especially at night, and it also helps those in bed stay clean," said Daizo Igawa, manager of Muscle Corp, as he demonstrated the Robohelper automated toilet.