Smart Wheelchair Able to Avoid Collisions

Pooja Viswanathan has developed a smart wheelchair for elderly people suffering from Alzheimer’s Disease - photo by Martin Dee
Pooja Viswanathan has developed a smart wheelchair for elderly
people suffering from Alzheimer’s Disease – photo
by Martin Dee

UBC Reports | Vol. 54 | No. 11 | Nov.
6, 2008

By Brian Lin

To Pooja Viswanathan, artificial intelligence is about people
creating smart tools that maximize human potential.

why, while some researchers are developing robotic wheelchairs
that simply transport users from one location to another,
she’s adamant about giving humans the final

“It’s counterproductive to give people who are
already suffering from physical and cognitive impairments
wheelchairs that further erode their capacity to make decisions,” says
the UBC Computer Science PhD student, “when the goal
is to give them back their independence.”

elderly people suffering from both physical disability and
degenerative diseases such as Alzheimer’s are not
granted access to powered wheelchairs due to safety concerns.

“It’s heartbreaking to see, in many long term
care homes, elders slumped over a manual wheelchair because
they are too weak or too confused to power their own way
to where they want to be. It’s frustrating for them
and often causes isolation and depression,” says Viswanathan,
whose brother worked at a nursing home.

Viswanathan is developing a prototype smart wheelchair that
could give users better quality of life and free up some
healthcare resources at the same time. Named Navigation and
Obstacle Avoidance Help, or NOAH, the system incorporates
a stereo-vision camera that can easily be retrofitted onto
any commercially available powered wheelchair, as well as
software that learns the behaviour and decision-making patterns
of its users.

“The twin cameras work similarly to human eyes,” says
Viswanathan. “They memorize landmarks to create maps
and calibrate distance to avoid collisions — which
is the only time the wheelchair takes over control.”

Designed to operate on a laptop that fits under the wheelchair,
and interact with the user through audio suggestions, NOAH
is also capable of incorporating the user’s daily schedules.

“For navigation and for people suffering from cognitive
impairments, audio prompts have been found to be more effective
than visual cues,” says Viswanathan. “People
with cognitive impairments often need extra time to process
new information, so it’s important that NOAH doesn’t
harangue them but rather offers suggestions at the right

NOAH — and data it collects from the user — can
easily be transferred to another wheelchair in case of a
move. The prototype is expected to be tested in a patient
care facility next year.