Austin Whitney and students in Homayoon |
When
graduating senior Austin Whitney hears his name called this Saturday at
the University of California, Berkeley’s Commencement 2011, he will
rise out of his wheelchair, walk to Chancellor Robert Birgeneau and
shake his hand.
That
moment will cap a long and dramatic journey for Whitney, who was
instantly paralyzed in 2007 when a car accident severed his spinal cord.
In the four years that passed, life lessons were learned, Whitney’s
spirit rebounded, and technological advances were explored. Last year,
Whitney began working with a team of UC Berkeley engineers developing
exoskeletons, wearable robotics that look like souped-up leg braces, and
found himself imagining the unimaginable – a graduation walk.
“Ask
anybody in a wheelchair; ask what it would mean to once again stand and
shake someone’s hand while facing them at eye level,” said Whitney, 22,
a double major in history and political science. “It will be surreal,
like a dream.”
Making
that dream happen has humanized the exoskeleton project for Homayoon
Kazerooni, professor of mechanical engineering, and his team of UC
Berkeley graduate students, so much so that they named it “Austin” in
honor of its first human test pilot.
Core
members of the team include Michael McKinley, Jason Reid, Wayne Tung
and Minerva Pillai, all Ph.D. students in Kazerooni’s Robotics and Human
Engineering Laboratory. They have worked around the clock for the past
year – and especially for the past few months – in preparation for
commencement, an annual event that honors all graduating seniors.
“In
the beginning, we hadn’t realized how important Austin’s role would
be,” said Reid. “The feedback he provides – from the comfort level of
straps to the ease of control – has really helped us fine tune the
design of this machine.”
A life-changing injury
Austin
Whitney grew up in San Juan Capistrano in Southern California. He was
involved in student government and theater, played sports, and excelled
in academics, graduating in 2007 with a 4.0 GPA. He also was not immune
to the feelings of invincibility so characteristic of youth. After
drinking with friends on a summer day in July 2007, Whitney got behind
the wheel of a car and crashed into a tree.
Austin Whitney wearing the exoskeleton. Image: Sarah Peet Photography |
His
spinal cord was severed just above the hip. He was hospitalized for 41
days and embarked on a tough physical and psychological recovery, but he
refused to let the accident detour his plans for college.
Wasting
no time, he started attending college classes 10 days after being
released from the hospital. He attended UC Santa Barbara before
transferring to UC Berkeley as a sophomore. Nearly four years after his
accident, Whitney is about to finish his undergraduate studies.
Exoskeletons evolve
The
Austin project represents the latest in a series of exoskeletons
Kazerooni and his team have developed over the past decade. Kazerooni’s
work in this field began in earnest in 2000 with a Defense Advanced
Research Projects Agency-funded project to create a device that can help
users carry heavier loads for longer periods of time. That project led
to the Berkeley Lower Extremity Exoskeleton (BLEEX),
a machine unveiled in 2004. At that time, Kazerooni also realized the
potential use for exoskeletons in the medical field, particularly for
physical rehabilitation and as an alternative to wheelchairs.
Aided
by increasingly powerful batteries and faster computer processors,
among other advances, there has been significant progress made in recent
years in exoskeleton research, not just by Kazerooni and Berkeley
Bionics, the company he co-founded in 2005, but by research teams around
the world.
In
2009, Kazerooni and his team jointly developed with Berkeley Bionics
the Human Universal Load Carrier (HULC), a successor to BLEEX. Last
year, Berkeley Bionics also successfully launched an exoskeleton for
paraplegics called eLegs. Another exoskeleton by Israeli company Argo
Medical Technologies was even featured in an episode of the TV show
“Glee.”
Prof. Kazerooni discusses the motivation for building “Austin”
“What
distinguishes the Austin exoskeleton from the others out there is its
simplicity for unsupervised in-home use and its lower cost,” said
Kazerooni. “We made the conscious decision to only focus on key
functions to keep the cost down. Users won’t be able to walk backward or
climb ladders with the Austin exoskeleton, but what we sacrifice in
capability, we gain in accessibility and affordability. Just getting
people to be upright and take steps forward is already a huge advance in
increasing independence.”
Kazerooni
noted that current exoskeletons on the market run about $100,000 and
up. Developing more affordable exoskeletons will bring this technology
to a larger group of people, he said.
“The
streamlined Austin exoskeleton is still in the early stages of research
and is not yet connected to a company for development, but I do not see
any real obstacle to bringing Austin exoskeletons to market at a price
comparable to some motorized wheelchairs,” said Kazerooni.
Keeping it simple
The
challenge, the researchers said, is to resist the temptation to
over-engineer the machine. Rather than rely upon a large number of
hardware components, they favored computation and elegant programming to
perform key functions.
“It
is much harder in engineering to keep things simple,” said Tung. “It’s
easy to just add more parts to do what you need, but that raises the
cost of production, and it means more things can go wrong.”
Ph.D. student Mike McKinley explains how the exoskeleton works
McKinley
added that this streamlined approach has more than a cost-benefit to
the end user. “With fewer components, we can make the exoskeletons
resulting from the Austin project easier to use, operate and maintain,”
he said. “Our goal was to create a workhorse device able to faithfully
handle the most essential tasks of daily life.”
Robotic
exoskeletons generally share similar elements: mechanical braces that
can be strapped onto the user’s legs and body, motorized joints
controlled by actuators, electronic sensors, a computer brain that
orchestrates the movements, and a portable power source.
When
possible, the researchers used off-the-shelf, low-power parts and
adapted them to their needs. They focused their efforts on the motions
considered critical for mobility: standing, walking forward, stopping
and sitting down. They then developed a number of innovations, including
the integration of components and having some parts perform dual
functions.
“If
you cut down on the number of motors, you can cut down on the number of
sensors needed, which in turn simplifies the device and leads to lower
cost, but this also makes the exoskeleton motion control more
complicated,” said Reid. “Sophisticated motion control adds little, if
anything, to the cost of production, but it requires a great deal of
research and creativity at the design stage. That is what we are doing.”
The
computer that sends movement instructions to the motors and gears is
worn in a small backpack, which also contains a rechargeable battery
that powers the Austin exoskeleton. A single charge can sustain the
exoskeleton for 4-8 hours of use. While the machine helps with movement,
the user is responsible for balancing, which means candidates for
exoskeletons must have some upper body control to manage that task.
“People
with permanent mobility disorders suffer from secondary injuries
resulting from long-term wheelchair use,” said Pillai. “This technology
offers an unprecedented degree of mobility and independence while
decreasing the likelihood of secondary injuries.”
Giving “the gift of hope”
It
may be years before the exoskeleton’s namesake will own his own
personal device, but Austin Whitney’s impact on its development has, and
will, be significant.
“This
team is so much more than just a group of researchers. They are my best
friends at the university,” said Whitney of the experience he’s had
with the engineers over the past year. “The exoskeleton the world will
see on Saturday will have been built with much more than just steel and
circuits – it has been built with compassion and a great devotion to the
idea of touching lives all around this world.”
Having
quit drinking after his accident, Whitney regularly shares his story
with students as an anti-drunk driving and motivational speaker, and is
now considering law school. He continues to maintain an active
lifestyle, helping to raise money for charities such as the Wheelchair
Foundation and the Swim with Mike Foundation, which provided him with a
scholarship. Whitney has also been recertified to scuba dive and is
working on his scuba diving instructor certification.
And
after May 14, he expects to add standing on stage before 15,000 people
at Edwards Track Stadium for UC Berkeley’s commencement to his
repertoire of achievements.
“This
work will constitute one of the most important endeavors I will ever do
in my life,” he said. “To have this knowledge of the larger picture, of
the possibility that this could affect the lives of countless people
around the globe, giving them the gift that I’ve been given – the gift
of hope – it truly puts even our most frustrating days in perspective
for me.”
