'Robotic legs' help stroke patients to walk again
Brain injuries from accidents, or strokes, leave many people unable to walk.
Now a Japanese company has developed what may be a way forward.
It is a robotic wrap around belt and legs, like a mechanical pair of trousers, that can be attached to a patient to help them stand up and take steps.
Even one of the worst health crises of her long life does not stop Nobuko Nishi smiling.
The 77-year-old beams at the doctors and nurses as she uses her right leg to scoot her wheelchair down a corridor in a hospital outside Tokyo.
A month ago she had a stroke and it has left her left side severely weakened.
Her left arm is in a sling, her left leg propped up on a footrest.
Mrs Nishi has been chosen to try out a new device developed to help people like her walk again. It is a pair of robotic legs.
A physiotherapist helps strap her in. From a hip joint there are struts running down the outside of her thighs, to another joint level with her knees.
The metal and plastic rods also run down her calves to special shoes she can put her feet in.
The two limbs are joined together by a wide belt that goes round the back of Mrs Nishi's hips.
The rehabilitation room is full of other elderly patients who have had strokes.
Japan is, after all, one of the most rapidly ageing societies in the world.
Some are being massaged to ease tightened muscles. Others are learning to walk again, gingerly clinging on to parallel bars.
Many turn to look as Mrs Nishi grasps the back of a chair, and with a whirr of motors rises to her feet.
"Before I could walk without any difficulty, but because of my stroke I've had to start again from the scratch," she says.
"It's very difficult to get on my feet. I am delighted that with the help of Roboto-san - Mr Robot - I can actually move again."
After just a few minutes Mrs Nishi feels up to trying the stairs. She is a little unsteady, but manages to get up and down without any mishaps.
The Hybrid Assistive Limb has been developed by a company called Cyberdyne, and is now being tried out in hospitals in Japan.
Sensor pads on the skin pick up the body's electrical signals. When the patient moves her leg, the machine moves in unison.
It is rather like having an extra set of muscles to help out.
A full body suit is also available, which the company suggests could be used by staff who need to move patients in nursing homes, in factories where heavy lifting is needed or disaster zones.
Mrs Nishi's doctor, Shinichiro Maeshima, says the robotic legs help motivate patients and staff during rehabilitation.
And he hopes the technology could one day offer the hope that people who have been paralysed will be able to walk again.
"It is very important to mix up medicine and technology," he says. "Our target is that the patient becomes happy and lives comfortably."
Guide dog alternative
Other firms in Japan are also trying to apply robotics to the needs of the ageing population.
In Osaka a company called Vstone has developed a machine they hope could one day usurp the role of guide dogs.
About the size of a child it can talk, move its arms and head, and travel about on wheels. With cameras in the place of eyes it can see where it is going and recognise faces.
"He can speak with humans," says Naoki Shibatani as the robot runs through its routine. "He would work at a hospital or nursing home, or a shopping avenue.
"His job is a guide and we want this robot to lead a blind person."
With a nod to the Japanese enthusiasm for things to be kawaii, or cute, the robot has been designed to be endearing.
When setting off it politely asks the user, "Shall we go for a walk", and offers a hand to hold.
It is a vision of the future in which robots do not just help people to walk, but are companions in life.