Japan’s ageing crisis has left the country with a unique catalogue of problems, among them a spiralling pensions shortfall and a surprising rise in crimes committed by the elderly.

Nasty falls, however, may be things of the past — thanks to the invention of the human airbag.

Simply strap the 2½lb (1.1kg) pouch around the waist and the wearer is armed with the cutting edge of protection. Sensors detect movement and have been programmed to know when things have gone wrong — a slip on something wet, a stumble on an uneven paving stone or a fall down stairs.

Within a tenth of a second, the airbags inflate to the size of three footballs as they are blasted into action with 15 litres of compressed gas, offering a soft slab of padding on the most vulnerable parts of the body in a fall: the back of the head and the bottom.

The price tag on the device — about £700 — offers a hint at just how big the “silver yen” has become as a business proposition.

The people most likely to pay for them are not the pensioners, but their guilt-ridden children, whose punishing work commitments prevent them from checking up on their parents more regularly.

Plenty of devices already cater for the market. Foremost among them is the I-Pot, an intelligent kettle that offers round-the-clock monitoring and surveillance of its owner.

The theory is that, when they are at home, elderly Japanese make themselves an average of two cups of tea every hour — and the kettle will send a text message to a son or daughter as soon as it is not used at normal intervals. If the tea-drinking rate drops to zero, it might be time to call to find out what is going on, or alert a friendly neighbour.

Across Japan, some of the country’s most technologically advanced companies have been re-equipping for a greyer future. Furniture companies have designed special beds that help to get older people up in the mornings and makers of park equipment have swapped the traditional swings and slides for gentle stretching devices for silver strollers.

The raw statistics justify the investment: almost 22 per cent of the population is already over 65 — compared with fewer than 13 per cent in the US, for example — and the world-beating life expectancies for men and women in Japan ensure that most will live into their late eighties.

Other gadgets for the elderly

Liquid level indicator Device fitted to cups or jugs that beeps when liquid is an inch from the top of the container

Bed occupancy sensor sends a warning to a monitoring centre if a bed is left unoccupied for a certain period, indicating a possible fall

Dolls that weigh as much as a baby and tell owners they love them, and welcome them back to the house — very popular with elderly women

Brain training game Nintendo gadget successful with elderly Japanese who use the mathematical and spelling puzzles to keep them mentally agile

Light-up slippers Footwear with miniature pressure-activated torches designed to prevent night-time falls

Sources: Archives, Tomy, Nintendo, Senior Shops

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